JP7781685B2 - Toner and toner manufacturing method - Google Patents

Description

This disclosure relates to toner used in electrophotographic image forming devices and a method for manufacturing the toner.

In recent years, there has been an increasing demand for energy-saving features in electrophotographic image forming devices. As a measure to save energy, technologies that fix toner at low temperatures are being considered in order to reduce power consumption in the fixing process. One method for improving the low-temperature fixability of toner is to lower the glass transition point of the toner's resin component. However, lowering the glass transition point of the toner's resin component leads to a decrease in the toner's heat-resistant storage stability, making it difficult to achieve both low-temperature fixability and heat-resistant storage stability with this method.

Therefore, in order to achieve both low-temperature fixability and heat-resistant storage stability in toner, methods of using crystalline resins in toner are being considered. Amorphous resins, which are commonly used as binder resins in toner, do not show a clear endothermic peak in differential scanning calorimetry (DSC measurement). On the other hand, crystalline resins do show an endothermic peak. This is because crystalline resins have the characteristic of not softening much up to their melting point, but softening by suddenly melting (sharp melting) once the melting point is reached. Due to their ability to achieve sharp melting, toners using crystalline resins as binder resins are attracting attention as they can achieve both excellent low-temperature fixability and heat-resistant storage stability.

One example of a crystalline resin used as a binder resin for toner is crystalline vinyl resin. Crystalline vinyl resin is a vinyl polymer in which a monomer unit having a long-chain alkyl group is incorporated into the main chain. In addition to the main chain skeleton, it has long-chain alkyl groups as side chains, and the long-chain alkyl groups in the side chains are regularly arranged within and between molecules, resulting in crystallization and exhibiting crystallinity. For example, Patent Document 1 discloses a toner containing a vinyl resin using a (meth)acrylic acid ester having a long-chain alkyl group.

Japanese Patent Application Laid-Open No. 2002-108018 JP 2014-130243 A Japanese Patent Application Laid-Open No. 2019-219646

Crystalized crystalline vinyl resin has a characteristic of forming a lamellar structure. A lamellar structure, in which molecules are regularly arranged, allows the molecules to easily loosen, making it advantageous for low-temperature fixing. However, it also has the property that its resistance to impact varies depending on the direction of the impact. For example, cracks that are parallel to the lamellar structure tend to extend in the direction of propagation and spread. For this reason, toner that uses crystalline vinyl resin as a binder resin may be prone to chipping when subjected to impact during endurance testing. In addition, streaks and cracks that occur when fixed images are bent may easily spread.

In Patent Document 2, the bending resistance is improved by using an amorphous resin as the shell, which has an SP value close to that of the binder resin (core) of the crystalline vinyl resin. The mechanism by which the bending resistance is improved is that the melted core and shell blend together during fixing, and the main chains of the core and shell become entangled. On the other hand, in Patent Document 3, the SP is used to prevent crystallization from being hindered.
The elasticity of the crystalline vinyl resin itself is strengthened by using a crosslinking agent with a specified value, thereby improving durability and bending resistance.

However, after extensive research, the inventors discovered that the durability of the toner in Patent Document 2 before fixing is insufficient, and that the folding resistance of the fixed image tends to decrease when the toner loading is high. The inventors speculate that the reason for the insufficient durability is insufficient adhesion between the amorphous resin shell and the crystalline portion of the crystalline vinyl resin.

In other words, even though the shell and core resins are compatible with each other, there is little interaction between the crystals formed by the side chains of the crystalline vinyl resin and the amorphous resin that makes up the shell, and we believe that the adhesion between the shell and the crystals is insufficient. As a result, we believe that the shell does not fully fulfill its role of stopping cracks in the crystals. We also believe that the same is the reason why bending resistance tends to decrease in fixed images with a high toner load, which are thought to be relatively prone to cracking.

Meanwhile, after extensive investigation, Patent Document 3 found that fixed images with low toner coverage had insufficient bending resistance. The reason for this is speculated as follows: Patent Document 3 uses a crosslinking agent to improve durability and bending resistance. However, it is thought that increased elasticity tends to reduce the adhesion between toner particles during fixing and the ease with which the toner penetrates into the paper. Therefore, while there is no problem with fixed images with sufficient toner coverage, when an image with low coverage and sparse toner is folded, the toner easily peels off from the paper, which is thought to reduce bending resistance.

This disclosure provides a toner that has excellent bending resistance, low-temperature fixability, and durability regardless of the amount of toner loaded, and a method for producing the toner.

The present disclosure provides a toner having toner particles having a binder resin,
The binder resin contains resin A and resin B,
In differential scanning calorimetry using the toner as a sample, an endothermic peak derived from the resin A is observed, the peak top temperature of the largest endothermic peak is in the range of 50.0°C to 90.0°C, and the endothermic amount of the endothermic peak derived from the resin A is 30 J/g to 70 J/g per 1 g of the toner,
the content of the resin A in the toner particles is 60.0% by mass to 90.0% by mass,
The resin A contains 40.0% by mass to 70.0% by mass of a monomer unit (a) represented by the following formula (1),
The toner relates to a toner in which the resin B contains 5.0% by mass to 30.0% by mass of a monomer unit (b) represented by the following formula (2):

In formula (1), ^R1 represents a hydrogen atom or a methyl group, and n represents an integer of 15 to 31. In formula (2), ^R2 represents a hydrogen atom or a methyl group, and m represents an integer of 9 to 31.

The present disclosure also provides a method for producing a toner having toner particles containing a binder resin, the method comprising:
The binder resin contains resin A and resin B,
The resin A contains 40.0% by mass to 70.0% by mass of the monomer unit (a) represented by the above formula (1),
Resin B contains 5.0% by mass to 30.0% by mass of the monomer unit (b) represented by formula (2),
The production method relates to a toner production method comprising the steps of preparing a polymerizable monomer composition containing a polymerizable monomer capable of forming the resin A and the resin B, and polymerizing the polymerizable monomer contained in the polymerizable monomer composition to obtain the toner particles.

This disclosure makes it possible to provide a toner that has excellent bending resistance, low-temperature fixability, and durability regardless of the amount of toner carried.

When a numerical range is expressed as "XX or more and YY or less" or "XX to YY," it means that the numerical range includes the upper and lower limits, which are the endpoints, unless otherwise specified. When a numerical range is expressed in stages, the upper and lower limits of each numerical range can be combined in any combination. (Meth)acrylate means acrylate and/or methacrylate, and (meth)acrylic acid means acrylic acid and/or methacrylic acid.

A monomer unit is a unit that constitutes a polymer (polymer, resin), and refers to the reacted form of a monomer (polymerizable monomer). For example, one section of carbon-carbon bonds in the main chain formed by polymerizing a vinyl monomer in a polymer is one monomer unit. A vinyl monomer can be represented by the following formula (Z), and a vinyl monomer unit is a structural unit of a polymer, and is the reacted form of a monomer represented by the following formula (Z). A monomer unit may also be simply referred to as a "unit." In formula (Z), R _Z1 represents a hydrogen atom or an alkyl group (preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group), and R _Z2 represents an optional substituent.

A crystalline resin is a resin that shows a clear endothermic peak in differential scanning calorimetry (differential scanning calorimetry is also referred to as DSC measurement).

After considering the above-mentioned issues, the inventors of the present invention concluded that in order to ensure sufficient durability and bending resistance of a toner containing a crystalline vinyl resin, it is necessary to achieve both of the following two points: (1) high adhesion between the crystalline vinyl resin and the crystalline portion of the resin used in combination with the crystalline vinyl resin, and (2) good compatibility between toner particles and between toner particles and paper during fixing.

After extensive investigation, we discovered that the above-mentioned problems could be solved by appropriately controlling the toner's endothermic peak, endothermic amount, and the content of the crystalline vinyl resin used as the main component, and by further using a resin containing a specific monomer equivalent to the monomer used in the crystalline vinyl resin. Specifically, this specific monomer is equivalent to the monomer contained in the crystalline vinyl resin, the main component of the toner, that forms the side chain that provides crystallinity. A resin (amorphous resin) containing a small amount of this specific monomer and that does not have a clear endothermic peak in differential scanning calorimetry was used in combination with the crystalline vinyl resin as the binder resin for the toner. This resulted in excellent durability and bending resistance while maintaining excellent low-temperature fixability.

Therefore, the present disclosure provides a toner having toner particles having a binder resin,
The binder resin contains resin A and resin B,
In differential scanning calorimetry using the toner as a sample, an endothermic peak derived from the resin A is observed, the peak top temperature of the largest endothermic peak is in the range of 50.0°C to 90.0°C, and the endothermic amount of the endothermic peak derived from the resin A is 30 J/g to 70 J/g per 1 g of the toner,
the content of the resin A in the toner particles is 60.0% by mass to 90.0% by mass,
The resin A contains 40.0% by mass to 70.0% by mass of the monomer unit (a) represented by the above formula (1),
The toner comprises resin B having 5.0% by mass to 30.0% by mass of the monomer unit (b) represented by the above formula (2).
[In formula (1), ^R1 represents a hydrogen atom or a methyl group, and n represents an integer of 15 to 31. In formula (2), ^R2 represents a hydrogen atom or a methyl group, and m represents an integer of 9 to 31.]

First, the inventors believe the mechanism by which excellent durability is achieved is as follows. By incorporating a monomer equivalent to that of resin A into resin B, an interaction between the side chains of resin A and resin B within the toner is created, improving the adhesion between resin A, which has a lamellar structure, and resin B, which does not. This makes it easier for resin B to stop the spread of cracks that occur in resin A, resulting in excellent durability. The assumed mechanism by which excellent bending resistance is achieved in fixed images with a high toner load is also thought to be similar. Another reason is that resin B is more likely to disperse within the crystals of resin A within the fixed image, making it easier to effectively stop cracks.

The present inventors further consider the mechanism by which excellent bending resistance is obtained in fixed images with low toner loading as follows: Resin A contains a large amount of long-chain alkyl groups in its side chains, making it highly hydrophobic and difficult to blend with paper. It is believed that dispersing Resin B, which does not contain a large amount of alkyl groups and has relatively low hydrophobicity, in the resin A improves its ability to blend with paper. Furthermore, because Resin A and Resin B adhere easily to each other, it is believed that they do not inhibit the adhesion of adjacent toner particles in the fixed image, making it difficult for toner particles to peel off from the paper when the paper is bent.

<Physical Properties of Toner and Toner Particles>
In differential scanning calorimetry using a toner sample, an endothermic peak derived from resin A is observed, and the peak-top temperature of the largest endothermic peak among the observed endothermic peaks is in the range of 50.0°C to 90.0°C. The fact that a toner has an endothermic peak indicates that resin A is contained in the toner in a crystalline state. When the peak-top temperature of the largest endothermic peak is 50.0°C or higher, the toner has excellent storage stability, and when it is 90.0°C or lower, the toner has excellent low-temperature fixability. Therefore, when the melting point is within the above range, the toner can achieve both low-temperature fixability and heat-resistant storage stability. A melting point of 50.0°C to 70.0°C is more preferable, as it improves low-temperature fixability.

The endothermic amount of the endothermic peak derived from resin A is 30 J/g to 70 J/g per gram of toner. When multiple endothermic peaks derived from resin A are observed, the total endothermic amount of these peaks is the endothermic amount in the present invention. The endothermic amount indicates the amount of resin A present in a crystalline state in the toner. A value of 30 J/g or more results in a toner with excellent low-temperature fixing properties and heat-resistant storage stability. A value of 70 J/g or less results in a toner with excellent bending resistance, with crystal cracks less likely to extend. The endothermic amount is preferably 35 J/g to 60 J/g, and more preferably 40 J/g to 50 J/g. The endothermic amount can be controlled by the type and amount of long-chain alkyl groups in the resin A used, the content of resin A in the toner particles, etc.

<Resin component>
The toner particles have at least a resin A and a resin B.

<Resin A>
Resin A has a monomer unit (a) represented by the following formula (1).
[In formula (1), R ¹ represents a hydrogen atom or a methyl group, and n represents an integer of 15 to 31]

The monomer unit (a) contained in the resin A has a long-chain alkyl group (an alkyl group having 16 to 32 carbon atoms) as a side chain of the vinyl polymer resin A, and thus the resin A has crystallinity, resulting in a toner having excellent low-temperature fixability and heat-resistant storage stability. Furthermore, the resin A is preferably a crystalline resin that exhibits a clear endothermic peak in DSC measurement. The monomer unit (a) can be incorporated as a monomer unit of the resin A by vinyl polymerization of a (meth)acrylic acid ester having an alkyl group having 16 to 32 carbon atoms as a polymerizable monomer.

Examples of (meth)acrylic acid esters having an alkyl group containing 16 to 32 carbon atoms include (meth)acrylic acid esters having an alkyl group containing 16 to 32 carbon atoms [cetyl (meth)acrylate, stearyl (meth)acrylate, nonadecyl (meth)acrylate, eicosyl (meth)acrylate, heneicosanyl (meth)acrylate, behenyl (meth)acrylate, lignoceryl (meth)acrylate, ceryl (meth)acrylate, octacosyl (meth)acrylate, myricyl (meth)acrylate, etc.].

Of these, from the viewpoint of the low-temperature fixability and heat-resistant storage stability of the toner, preferably at least one selected from the group consisting of (meth)acrylic acid esters having a linear alkyl group with 16 to 32 carbon atoms, more preferably at least one selected from the group consisting of (meth)acrylic acid esters having an alkyl group with 18 to 30 carbon atoms, and even more preferably at least one selected from the group consisting of linear stearyl (meth)acrylate and behenyl (meth)acrylate. That is, in the above formula (1), the number of carbon atoms (n) is preferably 15 to 29, more preferably 17 to 29, and even more preferably 17 or 21. Furthermore, R ¹ is preferably a hydrogen atom.

The polymerizable monomer (hereinafter also referred to as "monomer (a)") that forms the monomer unit (a) and the monomer unit (a) may be used alone or in combination of two or more. The content of the monomer unit (a) in the resin A is 40.0% to 70.0% by mass. If the content is 40.0% by mass or more, a toner with excellent low-temperature fixability and heat-resistant storage stability is obtained. The content is preferably 45.0% by mass or more. On the other hand, if the content is 70.0% by mass or less, the degree of hydrophobicity and the amount of lamellae become appropriate, resulting in a toner with excellent bending resistance regardless of the toner loading. The content is preferably 65.0% by mass or less, and more preferably 60.0% by mass or less. The content of the monomer unit (a) is the sum of the content of all monomer units represented by the above formula (1), and this also applies when multiple monomer units (a) are present.

The content of resin A in the toner particles is 60.0% to 90.0% by mass. If this content is 60.0% by mass or higher, a toner with excellent low-temperature fixability is obtained. This content is preferably 70.0% by mass or higher, more preferably 75.0% by mass or higher, and even more preferably 80.0% by mass or higher. Preferably, the remaining components in the toner, excluding resin B, colorants, release agents, and other additives, are all resin A. On the other hand, this content is preferably 85.0% by mass or lower.

From the viewpoint of appropriately controlling the physical properties of the toner, it is preferable that the resin A has another monomer unit (c) different from the above-mentioned monomer unit (a). The other monomer unit can be incorporated as a monomer unit of the resin A by vinyl polymerization of a polymerizable monomer (hereinafter also referred to as the other monomer) described below together with the polymerizable monomer that forms the monomer unit (a). When the SP value of the monomer unit (a) is SPa and the SP value of the monomer unit (c) is SPc, it is preferable that the following formula (3) is satisfied:
3.0≦(SPc-SPa)≦25.0...(3)

SPc-SPa is more preferably 5.0 or more and 10.0 or less. By satisfying the above formula (3), the crystallinity of resin A is less likely to decrease, and the melting point is more likely to be maintained. This makes it easier to achieve both low-temperature fixability and heat-resistant storage stability.

When the monomer unit (a) is composed of two or more types of (meth)acrylic acid esters having alkyl groups with 16 to 32 carbon atoms, SPa represents the average value calculated from the molar ratio of the amount of monomer (a) constituting each monomer unit.

On the other hand, when the monomer unit (c) is composed of two or more types of polymerizable monomers, SPc represents the SP value of the monomer unit derived from each polymerizable monomer, and SPc-SPa is determined for the monomer unit derived from each polymerizable monomer.

The content of monomer unit (c) satisfying formula (3) in resin A is preferably 20.0% by mass or more, and more preferably 25.0% by mass or more. A content of monomer unit (c) of 20.0% by mass or more facilitates the sharp melting properties of resin A and improves low-temperature fixability. Furthermore, crystallinity is less likely to decrease and the melting point is more likely to be maintained, improving heat-resistant storage stability. While there is no particular upper limit to this content, it is preferably 40.0% by mass or less, and more preferably 35.0% by mass or less. When resin A contains two or more types of monomer unit (c) satisfying formula (3), the proportion of monomer unit (c) is the total mass % of those units.

Examples of the polymerizable monomer (c) that forms the monomer unit (c) include, among the polymerizable monomers listed below, polymerizable monomers that satisfy the above formula (3). The polymerizable monomer (c) may be used alone or in combination of two or more.
Monomers having a nitrile group; for example, acrylonitrile, methacrylonitrile, etc.
Monomers having a hydroxy group: for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, etc.

Monomers having an amide group; for example, acrylamide, a monomer obtained by reacting an amine having 1 to 30 carbon atoms with a carboxylic acid having 2 to 30 carbon atoms (such as acrylic acid or methacrylic acid) having an ethylenically unsaturated bond using a known method.

Monomers having a urethane group: for example, alcohols having 2 to 22 carbon atoms and having an ethylenically unsaturated bond (e.g., 2-hydroxyethyl methacrylate, vinyl alcohol, etc.) and isocyanates having 1 to 30 carbon atoms [monoisocyanate compounds (e.g., benzenesulfonyl isocyanate, tosyl isocyanate, phenyl isocyanate, p-chlorophenyl isocyanate, butyl isocyanate, hexyl isocyanate, t-butyl isocyanate, cyclohexyl isocyanate, octyl isocyanate, 2-ethylhexyl isocyanate, dodecyl isocyanate, adamantyl isocyanate, 2,6-dimethylphenyl isocyanate, 3,5-dimethylphenyl isocyanate, and 2,6-dipropylphenyl isocyanate, etc.], aliphatic diisocyanates, Diisocyanate compounds (trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, etc.), alicyclic diisocyanate compounds (1,3-cyclopentene diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated tetramethylxylylene diisocyanate, etc.), and aromatic diisocyanate compounds (phenyl diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 2,2'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-toluidine diisocyanate, 4,4'-diphenylether diisocyanate, 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, xylylene diisocyanate, etc.), and a monomer obtained by reacting such monomer by a known method with an alcohol having 1 to 26 carbon atoms (methanol, ethanol, propanol, isopropyl alcohol, butanol, t-butyl alcohol, pentanol, heptanol, octanol, 2-ethylhexanol, nonanol, decanol, undecyl alcohol, lauryl alcohol, dodecyl alcohol, etc. , myristyl alcohol, pentadecyl alcohol, cetanol, heptadecanol, stearyl alcohol, isostearyl alcohol, elaidyl alcohol, oleyl alcohol, linoleyl alcohol, linolenyl alcohol, nonadecyl alcohol, heneicosanol, behenyl alcohol, erucyl alcohol, etc.) with an isocyanate having 2 to 30 carbon atoms and an ethylenically unsaturated bond [2-isocyanatoethyl (meth)acrylate, 2-(0-[1'-methylpropylideneamino]carboxyamino)ethyl (meth)acrylate, 2-[(3,5-dimethylpyrazolyl)carbonylamino]ethyl (meth)acrylate, 1,1-(bis(meth)acryloyloxymethyl)ethyl isocyanate, etc.] by a known method, and the like.

Monomers having a urea group: for example, monomers obtained by reacting an amine having 3 to 22 carbon atoms [primary amines (normal butylamine, t-butylamine, propylamine, isopropylamine, etc.), secondary amines (di-normal ethylamine, di-normal propylamine, di-normal butylamine, etc.), aniline, cycloxylamine, etc.] with an isocyanate having 2 to 30 carbon atoms and an ethylenically unsaturated bond by a known method.
Monomers having a carboxy group: for example, methacrylic acid, acrylic acid, and 2-carboxyethyl (meth)acrylate.

Also used as the polymerizable monomer (c) are vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl caprylate, vinyl caprate, vinyl laurate, vinyl myristate, vinyl palmitate, vinyl stearate, vinyl pivalate, and vinyl octylate.

Among these, the monomer unit (c) is preferably at least one selected from the group consisting of monomer units represented by the following formulas (4a) to (4c), and more preferably represented by the following formula (4).
[In the formula, ^R3 represents a hydrogen atom or a methyl group.]

By containing the monomer unit represented by formula (4) above, the crystallization of resin A is less likely to be inhibited, and the melting point is more likely to be increased, resulting in improved low-temperature fixability and heat-resistant storage stability. The monomer forming monomer unit (c) is preferably at least one selected from the group consisting of (meth)acrylonitrile, (meth)acrylamide, and vinyl acetate. Acrylonitrile and methacrylonitrile are even more preferred.

In addition to the monomer unit (a) and the monomer unit (c) that satisfies the above formula (3), resin A may also contain one or more other monomer units that do not satisfy the above formula (3). There are no particular restrictions on the units that do not satisfy the above formula (3), but it is preferable that they consist of the following polymerizable monomers in addition to the polymerizable monomers described above.

(Meth)acrylic acid esters: methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, etc.; Styrenes: styrene, α-methylstyrene, etc.

Among these, the use of ethyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, or styrene is preferred because it makes it easier to appropriately control the elasticity of the toner. That is, preferably, Resin A has at least one selected from the group consisting of a monomer unit represented by the following formula (St) in which styrene is polymerized, and a monomer unit represented by the following formula (Ac) in which a (meth)acrylic acid ester is polymerized. More preferably, Resin A has a monomer unit represented by the following formula (St). In formula (Ac), R ⁶ represents a hydrogen atom or a methyl group, and R ⁷ represents an alkyl group having 1 to 4 carbon atoms (preferably 1 to 3, more preferably 1 or 2, and even more preferably 2).

The content of the monomer unit represented by formula (St) in Resin A is preferably 1.0% to 30.0% by mass, and more preferably 4.0% to 25.0% by mass. The content of the monomer unit represented by formula (Ac) in Resin A is preferably 0.0% to 20.0% by mass, and more preferably 5.0% to 15.0% by mass.

The acid value AvA of Resin A is preferably 5.0 mgKOH/g or less. Polymerizable monomers capable of imparting an acid value to Resin A tend to inhibit the crystallization of the monomer unit (a). Therefore, an acid value AvA of 5.0 mgKOH/g or less ensures sufficient crystallinity of Resin A, which tends to improve low-temperature fixability and heat-resistant storage stability. More preferably, it is 0 mgKOH/g or more and 3.0 mgKOH/g or less, even more preferably 0 mgKOH/g or more and 1.0 mgKOH/g or less, and even more preferably, Resin A has no acid value, i.e., 0 mgKOH/g.

<Resin B>
Resin B has a monomer unit (b) represented by the following formula (2).

[In formula (2), ^R2 represents a hydrogen atom or a methyl group, and m represents an integer of 9 to 31.]

The monomer unit (b) of resin B has a long-chain alkyl group (an alkyl group having 10 to 32 carbon atoms) similar in structure to the side chain of the monomer unit (a) that exhibits the crystallinity of resin A, which improves compatibility between resin A and resin B. Furthermore, the interaction between the long-chain alkyl groups facilitates adhesion between the crystals of resin A and resin B. Therefore, the mechanism described above is expected to work, resulting in a toner with excellent durability and bending resistance. Furthermore, resin B is preferably a resin that does not exhibit a clear endothermic peak in DSC measurement, i.e., is preferably an amorphous resin. The glass transition temperature (TgB) of resin B is preferably 30.0°C to 90.0°C, more preferably 50.0°C to 80.0°C.

Because Resin B is amorphous, Resin A crystals are less likely to connect over a wide area, and Resin B is more likely to play a role in stopping cracks, improving durability and the bending resistance of images with a high toner load. Having a TgB of 30.0°C or higher improves heat-resistant storage stability, and having a TgB of 90.0°C or lower improves low-temperature fixability.

Monomer unit (b) can be incorporated into resin B as a monomer unit by vinyl polymerization of a (meth)acrylic acid ester having an alkyl group with 10 to 32 carbon atoms as a polymerizable monomer. The number of carbon atoms (m) is preferably 11 to 29, and more preferably 15 to 23.

Examples of (meth)acrylic acid esters having an alkyl group having 10 to 32 carbon atoms include (meth)acrylic acid esters having a linear alkyl group having 10 to 32 carbon atoms [decyl (meth)acrylate, heptadecyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, cetyl (meth)acrylate, heptadecyl (meth)acrylate, stearyl (meth)acrylate, nonadecyl (meth)acrylate, eicosyl (meth)acrylate, heneicosanyl (meth)acrylate, behenyl (meth)acrylate, lignoceryl (meth)acrylate, ceryl (meth)acrylate, octacosyl (meth)acrylate, myricyl (meth)acrylate, etc.].

Among these, it is preferable that the absolute value of the difference |n-m| between n in formula (1), i.e., the number of carbon atoms n of the long-chain alkyl group in monomer unit (a), and m in formula (2), i.e., the number of carbon atoms m of the long-chain alkyl group in monomer unit (b), is 10 or less. When n and m are close to each other, the interaction between the long-chain alkyl groups becomes stronger, which tends to improve the adhesion between resin A and resin B, thereby improving durability and bending resistance. More preferably, |n-m| is 0 or more and 5 or less, even more preferably, |n-m| is 0 or more and 2 or less, and even more preferably, |n-m| is 0. Resin B may use one type of monomer unit (b) alone, or two or more types may be used in combination.

The content of monomer unit (b) in resin B is 5.0% to 30.0% by mass. When this content is 5.0% by mass or more, resin A and resin B become more compatible and adhesion is improved, resulting in a toner with excellent durability and bending resistance. Furthermore, resin B is easily dispersed in melted resin A during fixing, resulting in excellent durability and bending resistance (when the loading amount is large). Additionally, toner particles in the fixed image tend to stick together, resulting in excellent bending resistance (when the loading amount is small). Meanwhile, when this content is 30.0% by mass or less, resin B is less likely to crystallize and form a lamellar structure, making it less likely for cracks to spread. Furthermore, while resin B adheres closely to resin A, its composition is different and it is less compatible, making it easier to prevent crack extension.

As a result, excellent durability and bending resistance (when a large amount is applied) are obtained. Resin B preferably contains 5.0% to 25.0% by mass, and more preferably 10.0% to 20.0% by mass, of monomer unit (b) represented by formula (2). The content of monomer unit (b) is the sum of the content of all monomer units represented by formula (2). The same applies when multiple monomer units (b) are present.

In addition to monomer unit (b), resin B may contain one or more other monomer units that do not satisfy the above conditions. Examples of polymerizable monomers that form other monomer units include monomer unit (c) exemplified for resin A and monomers that form other monomer units.

Resin B preferably has at least one selected from the group consisting of a monomer unit represented by the following formula (7) and a monomer unit represented by the following formula (8). Resin B more preferably has monomer units represented by the following formulas (7) and (8). Resin B also preferably has a monomer unit represented by the following formula (St). In the formulas, ^R8 and ^R9 represent a hydrogen atom or a methyl group, and ^R10 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms (preferably 1 to 3, more preferably 1 or 2, and even more preferably 2), or a hydroxyalkyl group having 1 to 4 carbon atoms (preferably 1 to 3).

The content of the monomer unit represented by formula (7) in resin B is preferably 3.0% to 25.0% by mass, more preferably 10.0% to 20.0% by mass. The content of the monomer unit represented by formula (8) in resin B is preferably 0.5% to 35.0% by mass, more preferably 2.0% to 30.0% by mass. The content of the monomer unit represented by formula (St) in resin B is preferably 40.0% to 80.0% by mass, more preferably 50.0% to 70.0% by mass.

The content of Resin B in the toner particles is preferably 1.0% to 20.0% by mass. A content of 1.0% by mass or more improves durability and bending resistance, while a content of 20.0% by mass or less improves low-temperature fixability. It is more preferably 2.0 to 15.0% by mass, and even more preferably 3.0 to 8.0% by mass.

Furthermore, the weight-average molecular weight MwB of the tetrahydrofuran-soluble portion (THF-soluble portion) of resin B, as measured by gel permeation chromatography (GPC), is preferably 10,000 to 20,000, and more preferably 15,000 to 19,500. When MwB is 10,000 or more, resin B has high elasticity and is more likely to function as a crack stopper. When MwB is 20,000 or less, resin B is more likely to be finely dispersed in resin A in the fixed image, making cracks less likely to extend. Therefore, having MwB within the above range tends to improve bending resistance (when the loading amount is high). Furthermore, when MwB is 20,000 or less, resin B is less likely to inhibit adhesion between toner particles during fixing, and bending resistance (when the loading amount is low) tends to improve.

The acid value AvB of resin B is preferably 5.0 mgKOH/g to 30.0 mgKOH/g. When the acid value AvB is 5.0 mgKOH/g or more, the hydrophilicity of the toner is improved, and affinity with paper is likely to increase, so that bending resistance (when the loading amount is small) is likely to be good. When the acid value AvB is 30.0 mgKOH/g or less, resin B is likely to approach monomer unit (a) with a small acid value, and resin A and resin B are likely to adhere to each other, so that durability and bending resistance are further improved. More preferably, it is 10.0 mgKOH/g to 30.0 mgKOH/g.

The difference between the acid value AvA of Resin A and the acid value AvB of Resin B (AvB - AvA) is preferably 5.0 mgKOH/g or more. A difference of 5.0 mgKOH/g or more allows Resins A and B to adhere to each other, while Resin B is not completely miscible with Resin A, which helps prevent crack extension. This tends to improve durability and bending resistance. More preferably, AvB - AvA is 10.0 mgKOH/g or more. There is no particular upper limit for AvB - AvA, but it is preferably 30.0 mgKOH/g or less, and more preferably 20.0 mgKOH/g or less.

Furthermore, when the SP value of resin A is SPA (J/cm ³ ) ^0.5 and the SP value of resin B is SPB (J/cm ³ ) ^0.5 , it is preferable that the absolute value of the difference between SPA and SPB, |SPA-SPB|, satisfies the following formula (5):
0.2≦｜SPA-SPB｜≦2.0...(5)

When |SPA-SPB| is 0.2 or higher, resin B is less likely to be completely compatible with resin A and achieve a uniform state, making it easier for resin B to function as a crack-stopping resin. This tends to improve durability and bending resistance. Furthermore, when |SPA-SPB| is 2.0 or lower, resin A and resin B are more likely to be in close contact with each other, making it easier for durability and bending resistance to be improved. In other words, when the above relationship holds, even if resin A and resin B are in close contact with each other, resin B is more likely to be in a state where it is not compatible with resin A and exists independently. More preferably, 0.2≦|SPA-SPB|≦1.6.

The total content of resin A and resin B in the binder resin is preferably 80.0% by mass or more. It is more preferably 90.0% to 100.0% by mass, and even more preferably 95.0% to 100.0% by mass. Within this range, resin A is more likely to exhibit low-temperature fixability.

<Resins other than Resins A and B>
The binder resin may contain other resins that can be used as resin components of the toner, in addition to resin A and resin B. Examples of such resins include vinyl resins, polyester resins, polyurethane resins, and epoxy resins that do not fall under resin A and resin B.

When the other resin is a vinyl resin, the monomers that can be used for the above-mentioned resins A and B can be used in combinations that do not fall under the category of resins A and B. Two or more types of monomers for the other resins may be used in combination, if necessary.

Polyester resins can be obtained by the condensation polymerization reaction of divalent or higher polycarboxylic acids and polyhydric alcohols. Examples of polycarboxylic acids include the following: dibasic acids such as succinic acid, adipic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, malonic acid, and dodecenylsuccinic acid, as well as their anhydrides and lower alkyl esters; and aliphatic unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, and citraconic acid. 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, as well as their anhydrides and lower alkyl esters. These may be used alone or in combination.

Examples of polyhydric alcohols include the following compounds: alkylene glycols (ethylene glycol, 1,2-propylene glycol, and 1,3-propylene glycol); alkylene ether glycols (polyethylene glycol and polypropylene glycol); alicyclic diols (1,4-cyclohexanedimethanol); bisphenols (bisphenol A); and alkylene oxide (ethylene oxide and propylene oxide) adducts of alicyclic diols. The alkyl moieties of the alkylene glycols and alkylene ether glycols may be linear or branched. Further examples include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol. These may be used alone or in combination.

In addition, monovalent acids such as acetic acid and benzoic acid, and monovalent alcohols such as cyclohexanol and benzyl alcohol can also be used as needed to adjust the acid value and hydroxyl value. There are no particular restrictions on the method for producing polyester resins, but examples include transesterification and direct polycondensation.

Polyurethane resins are obtained by reacting a diol component with a diisocyanate component. Examples of diisocyanate components include aromatic diisocyanates with 6 to 20 carbon atoms (excluding carbon atoms in NCO groups, the same applies below), aliphatic diisocyanates with 2 to 18 carbon atoms, alicyclic diisocyanates with 4 to 15 carbon atoms, modified products of these diisocyanates (modified products containing urethane groups, carbodiimide groups, allophanate groups, urea groups, biuret groups, uretdione groups, uretoimine groups, isocyanurate groups, or oxazolidone groups; hereinafter also referred to as "modified diisocyanates"), and mixtures of two or more of these.

Aromatic diisocyanates include m- and/or p-xylylene diisocyanate (XDI) and α,α,α',α'-tetramethylxylylene diisocyanate.
Examples of aliphatic diisocyanates include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), and dodecamethylene diisocyanate.
Examples of alicyclic diisocyanates include isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4'-diisocyanate, cyclohexylene diisocyanate, and methylcyclohexylene diisocyanate.

Among these, aromatic diisocyanates having 6 to 15 carbon atoms, aliphatic diisocyanates having 4 to 12 carbon atoms, and alicyclic diisocyanates having 4 to 15 carbon atoms are preferred, with XDI, IPDI, and HDI being particularly preferred. In addition to the diisocyanate component, isocyanate compounds with a tri- or higher number can also be used. Diol components that can be used in polyurethanes include the same dihydric alcohols that can be used in polyesters described above.

<Wax>
The toner particles may contain a wax as a release agent. The wax is not particularly limited, but is preferably a hydrocarbon wax and/or an ester wax. By using a hydrocarbon wax and/or an ester wax, effective release properties can be easily ensured. The hydrocarbon wax is not particularly limited, but examples thereof include the following.

Aliphatic hydrocarbon waxes: low molecular weight polyethylene, low molecular weight polypropylene, low molecular weight olefin copolymer, Fischer-Tropsch wax, or waxes obtained by oxidizing or adding an acid to these.

The ester wax may be any wax having at least one ester bond in one molecule, and either a natural ester wax or a synthetic ester wax may be used.
The ester wax is not particularly limited, but examples thereof include the following:
Esters of monohydric alcohols and monocarboxylic acids, such as behenyl behenate, stearyl stearate, and palmityl palmitate;
Esters of dicarboxylic acids and monoalcohols, such as dibehenyl sebacate;
Esters of dihydric alcohols and monocarboxylic acids, such as ethylene glycol distearate and hexanediol dibehenate;
Esters of trihydric alcohols and monocarboxylic acids, such as glycerin tribehenate;
Esters of tetrahydric alcohols and monocarboxylic acids, such as pentaerythritol tetrastearate and pentaerythritol tetrapalmitate;
Esters of hexahydric alcohols and monocarboxylic acids, such as dipentaerythritol hexastearate, dipentaerythritol hexapalmitate, and dipentaerythritol hexabehenate;
Esters of polyfunctional alcohols and monocarboxylic acids, such as polyglycerin behenate; natural ester waxes, such as carnauba wax and rice wax;

Among these, esters of hexahydric alcohols and monocarboxylic acids, such as dipentaerythritol hexastearate, dipentaerythritol hexapalmitate, and dipentaerythritol hexabehenate, are preferred.

The wax may be a hydrocarbon wax or an ester wax, or a combination of a hydrocarbon wax and an ester wax, or a mixture of two or more types of each.

<Various additives>
If necessary, the toner may contain one or more additives selected from colorants, magnetic materials, charge control agents, fluidizing agents, etc. Various additives used in the toner will be specifically described below.

<Coloring Agent>
The toner may contain a colorant. Examples of colorants include known organic pigments, organic dyes, inorganic pigments, carbon black as a black colorant, and magnetic particles. Other colorants that have been used in conventional toners may also be used. Examples of yellow colorants include condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds. Specifically, C.I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 155, 168, and 180 are preferably used.

Magenta colorants include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. Specifically, C.I. Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 144, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221, and 254 are preferred.

Examples of cyan colorants include copper phthalocyanine compounds and their derivatives, anthraquinone compounds, and basic dye lake compounds. Specific examples include C.I. Pigment Blue 1,
7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, and 66 are preferably used.

The colorant may be selected based on hue angle, saturation, brightness, lightfastness, OHP transparency, and dispersibility in toner particles. If the colorant is not a magnetic particle, the content of the colorant is preferably 1.0 to 20.0 parts by mass per 100.0 parts by mass of the binder resin. If magnetic particles are used as the colorant, the content is preferably 40.0 parts by mass or more and 150.0 parts by mass or less per 100.0 parts by mass of the binder resin.

<Charge control agent>
Any known charge control agent can be used without any particular limitation. Examples of negative charge control agents include monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, oxycarboxylic acids, and dicarboxylic acid-based metal compounds. Examples of positive charge control agents include quaternary ammonium salts, polymeric compounds having quaternary ammonium salts in the side chains, guanidine compounds, pyridine-based compounds, nigrosine-based compounds, and imidazole compounds. The charge control agent is preferably contained in an amount of 0.01 to 20.0 parts by mass relative to 100.0 parts by mass of toner particles. More preferably, it is contained in an amount of 0.5 to 10.0 parts by mass.

<External additives>
An external additive may be added to the toner particles to produce a toner. Examples of the external additive include inorganic fine particles selected from the group consisting of silica fine particles, alumina fine particles, and titania fine particles, or composite oxides thereof. Examples of composite oxides include silica alumina fine particles and strontium titanate fine particles. The external additive is preferably contained in an amount of 0.01 to 8.0 parts by mass relative to 100 parts by mass of the toner particles. More preferably, the amount is 0.1 to 4.0 parts by mass.

<Toner manufacturing method>
The method for producing the toner particles is not particularly limited, and known methods such as suspension polymerization, emulsion aggregation, dissolution suspension, and pulverization can be used. Among them, suspension polymerization is preferred because it can suppress variations in the content ratio of resin A to resin B between toner particles and can easily improve low-temperature fixability, durability, and bending resistance. In particular, it is preferred to use the following production method for producing the toner.

A method for producing a toner having toner particles containing a binder resin, comprising:
The binder resin contains resin A and resin B,
The resin A contains 40.0% by mass to 70.0% by mass of the monomer unit (a) represented by the above formula (1),
Resin B contains 5.0% by mass to 30.0% by mass of the monomer unit (b) represented by formula (2),
The method for producing a toner comprises the steps of preparing a polymerizable monomer composition containing a polymerizable monomer capable of forming the resin A and the resin B, and polymerizing the polymerizable monomer contained in the polymerizable monomer composition to obtain toner particles.

The above manufacturing method will now be described in detail. Resin A and Resin B are as described above. By adopting the above manufacturing method, it is easier to obtain a toner with excellent low-temperature fixability, durability, and bending resistance.

The polymerizable monomer capable of forming Resin A is a (meth)acrylic acid ester having an alkyl group having 16 to 32 carbon atoms. The polymerizable monomer composition contains 40.0% by mass to 70.0% by mass (preferably 45.0% by mass to 65.0% by mass, more preferably 45.0% by mass to 60.0% by mass) of the (meth)acrylic acid ester having an alkyl group having 16 to 32 carbon atoms among the polymerizable monomers contained in the polymerizable monomer composition. The polymerizable monomer composition may contain a polymerizable monomer that forms the monomer unit (c) above, a polymerizable monomer that forms the monomer unit represented by Formula (St) above, and a polymerizable monomer that forms the monomer unit represented by Formula (Ac) above.

For example, pre-synthesized resin B is added to a mixture of polymerizable monomers that will produce resin A, and a polymerizable monomer composition containing other materials such as colorants, waxes, charge control agents, and crosslinking agents, as needed, is uniformly dissolved or dispersed therein to prepare a polymerizable monomer composition. The polymerizable monomer composition is then dispersed in an aqueous medium using a stirrer or similar device to prepare suspended particles of the polymerizable monomer composition. The polymerizable monomers contained in the particles are then polymerized using a polymerization initiator or similar agent to obtain toner particles.

After polymerization is complete, the toner particles are filtered, washed, and dried using known methods, and external additives are added as needed to obtain the toner. Including a step of dissolving pre-polymerized resin B in a monomer liquid of unpolymerized resin A makes it easier for resin A and resin B to form a state in which they are in close contact but not compatible with each other. Additionally, since variation in the content ratio of resin A to resin B between toner particles is reduced, the toner tends to have excellent low-temperature fixability, durability, and bending resistance.

Known polymerization initiators can be used as the polymerization initiator. Examples include azo or diazo polymerization initiators such as 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, and azobisisobutyronitrile; and peroxide polymerization initiators such as benzoyl peroxide, t-butylperoxy 2-ethylhexanoate, t-butylperoxypivalate, t-butylperoxyisobutyrate, t-butylperoxyneodecanoate, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, and lauroyl peroxide.

In addition, known chain transfer agents and polymerization inhibitors may be used. The aqueous medium may contain an inorganic or organic dispersion stabilizer. Known dispersion stabilizers can be used as the dispersion stabilizer.

Examples of inorganic dispersion stabilizers include phosphates such as hydroxyapatite, tricalcium phosphate, dicalcium phosphate, magnesium phosphate, aluminum phosphate, and zinc phosphate; carbonates such as calcium carbonate and magnesium carbonate; metal hydroxides such as calcium hydroxide, magnesium hydroxide, and aluminum hydroxide; sulfates such as calcium sulfate and barium sulfate; calcium metasilicate; bentonite; silica; and alumina.

On the other hand, examples of organic dispersion stabilizers include polyvinyl alcohol, gelatin, methyl cellulose, methylhydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, polyacrylic acid and its salts, and starch. When using an inorganic compound as a dispersion stabilizer, commercially available products may be used as is, but to obtain finer particles, the inorganic compound may be formed in an aqueous medium and then used. For example, in the case of calcium phosphate such as hydroxyapatite or tricalcium phosphate, an aqueous phosphate solution and an aqueous calcium salt solution may be mixed under high agitation.

The aqueous medium may contain a surfactant. Known surfactants can be used. Examples include anionic surfactants such as sodium dodecylbenzene sulfate and sodium oleate; cationic surfactants; amphoteric surfactants; and nonionic surfactants.

The measurement methods for each physical property are described below.
<Method for Separating Resin A and Resin B from Toner>
Separation of resin A and resin B from toner can be performed by known methods, but an example is shown below. Gradient LC is used as a method for separating resin components from toner. This analysis allows separation according to the polarity of the resin in the binder resin, regardless of molecular weight. First, the toner is dissolved in chloroform. The sample is adjusted to a sample concentration of 0.1% by mass with chloroform, and the solution is filtered through a 0.45 μm PTFE filter before being subjected to measurement. The gradient polymer LC measurement conditions are shown below.
Apparatus: ULTIMATE 3000 (Thermo Fisher Scientific)
Mobile phase: A chloroform (HPLC), B acetonitrile (HPLC)
Gradient: 2 min (A/B = 0/100) → 25 min (A/B = 100/0)
(The gradient of the mobile phase change was set to be linear.)
Flow rate: 1.0 mL/min Injection: 0.1 mass% x 20 μL
Column: Tosoh TSKgel ODS (4.6 mmφ x 150 mm x 5 μm)
Column temperature: 40°C
Detector: Corona Charged Aerosol Detector (Corona-CAD) (Therm
o Fisher Scientific)

The time-intensity graph obtained from the measurement shows a peak corresponding to the highly polar component, i.e., resin B, and a peak corresponding to the less polar component, i.e., resin A. Furthermore, if resins other than resin A and resin B are present, peaks corresponding to their polarity will be observed. After that, the above measurement is carried out again, and by collecting fractions at the times when the respective peaks reach their valleys, it is possible to separate resin A, resin B, and other resins.

If the toner contains a release agent, it is necessary to separate the release agent from the toner. The release agent is separated by recycling HPLC to separate components with a molecular weight of 2000 or less as the release agent. The measurement method is as follows: First, a chloroform solution of the toner is prepared using the method described above. The resulting solution is then filtered through a solvent-resistant membrane filter "Myshoridisc" (manufactured by Tosoh Corporation) with a pore size of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of components soluble in chloroform is 1.0% by mass. This sample solution is used to perform measurements under the following conditions.
・Device: LC-Sakura NEXT (manufactured by Japan Analytical Industry Co., Ltd.)
Column: JAIGEL 2H, 4H (manufactured by Japan Analytical Industry Co., Ltd.)
Eluent: chloroform Flow rate: 10.0 ml/min
Oven temperature: 40.0°C
Sample injection volume: 1.0 ml

In calculating the molecular weight of a sample, a molecular weight calibration curve prepared using standard polystyrene resins (for example, trade names "TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500", manufactured by Tosoh Corporation) is used.
From the molecular weight curve thus obtained, components having a molecular weight of 2000 or less are repeatedly separated and the release agent is removed from the toner.

<Method for measuring the content of various monomer units in a resin>
The content ratio of each monomer unit in the resin is measured by ¹ H-NMR under the following conditions.
Measuring device: FT NMR device JNM-EX400 (manufactured by JEOL Ltd.)
Measurement frequency: 400 MHz
Pulse condition: 5.0 μs
Frequency range: 10,500 Hz
Number of measurements: 64 Measurement temperature: 30°C

Sample: 50 mg of a measurement sample is placed in a sample tube with an inner diameter of 5 mm, deuterated chloroform (CDCl ₃ ) is added as a solvent, and the sample is dissolved in a thermostatic bath at 40°C. The obtained ¹ H-NMR chart is analyzed to identify the structure of each monomer unit. As an example, the measurement of the content ratio of monomer unit (a) in resin A is described here. In the obtained ¹ H-NMR chart, a peak that is independent of the peaks that are assigned to the components of monomer unit (a) is selected from the peaks assigned to the components of the other monomer units, and the integral value S1 of this peak is calculated. The integral values of the other monomer units contained in resin A are also calculated in the same manner.

When the monomer units constituting the resin A are the monomer unit (a) and one other monomer unit, the content of the monomer unit (a) is determined as follows using the above-mentioned integral value S1 and the integral value S2 of the peak of the other monomer unit: where n1 and n2 are the numbers of hydrogen atoms in the constituent elements to which the peak of interest for each site belongs.
Content of monomer unit (a) (mol %)=
{(S1/n1)/((S1/n1)+(S2/n2))}×100
Even when two or more other monomer units are present, the content of the monomer unit (a) can be calculated in the same manner.

When a polymerizable monomer containing no hydrogen atoms in components other than the vinyl group is used, the measurement nucleus is set to ¹³ C using ¹³ C-NMR, and measurement is performed in single pulse mode, and the content is calculated in the same manner using ¹ H-NMR. The proportion (mol %) of each monomer unit calculated by the above method is multiplied by the molecular weight of each monomer unit to convert the content of each monomer unit to mass %.

Furthermore, when NMR is measured using toner as a sample, the peaks of wax and resins other than Resin A may overlap, making it impossible to observe independent peaks. This may make it impossible to calculate the content of each monomer unit in Resin A. In such cases, Resin A' can be produced by carrying out the same production process without using wax or other resins, and this can be considered Resin A and analyzed. Resin B is also measured using the same method.

<Method for measuring weight average molecular weight (Mw) of resin>
The weight-average molecular weight (Mw) of a resin is measured by gel permeation chromatography (GPC) as follows. First, a sample is dissolved in tetrahydrofuran (THF) at room temperature for 24 hours. The resulting solution is then filtered through a solvent-resistant membrane filter "Myshoridisc" (manufactured by Tosoh Corporation) with a pore size of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of components soluble in THF is 0.8% by mass. Measurements are performed using this sample solution under the following conditions.
Apparatus: HLC8120 GPC (detector: RI) (manufactured by Tosoh Corporation)
Column: 7 columns of Shodex KF-801, 802, 803, 804, 805, 806, and 807 (manufactured by Showa Denko K.K.)
Eluent: tetrahydrofuran (THF)
Flow rate: 1.0 mL/min Oven temperature: 40.0°C
Sample injection volume: 0.10 mL

When calculating the molecular weight of a sample, a molecular weight calibration curve created using standard polystyrene resins (for example, trade names "TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500", manufactured by Tosoh Corporation) is used.

<Method for measuring endothermic peak temperature and endothermic amount>
The endothermic peak temperature (melting point) and endothermic amount of the toner or resin are measured using a DSC Q2000 (manufactured by TA Instruments) under the following conditions.
Temperature increase rate: 10°C/min
Measurement start temperature: 20℃
Measurement end temperature: 180°C
The melting points of indium and zinc are used to correct the temperature of the detector, and the heat of fusion of indium is used to correct the calorific value. Specifically, 5 mg of sample is precisely weighed and placed in an aluminum pan, and differential scanning calorimetry is performed. An empty silver pan is used as a reference. During the temperature rise process, the temperature is raised to 180°C at a rate of 10°C/min. The peak top temperature and endothermic value are then calculated from each peak.

In DSC measurements using toner as a sample, if the endothermic peak derived from resin A does not overlap with the endothermic peaks of other components such as the release agent, the endothermic peak obtained is regarded as the "endothermic peak derived from resin A." On the other hand, if the endothermic peaks of other components such as the release agent overlap with the endothermic peak derived from resin A, it is necessary to separate the endothermic peak derived from the release agent, etc.

For example, the endothermic peak attributable to the release agent can be separated by the following method to obtain the endothermic peak attributable to resin A. First, a separate DSC measurement is performed on the release agent alone to determine its endothermic characteristics. Next, the release agent content in the toner is determined. The release agent content in the toner can be measured using known structural analysis. After that, the endothermic peak attributable to the release agent can be determined from the release agent content in the toner, and this amount can be subtracted from the peak attributable to resin A.

If the release agent is highly compatible with resin A, it is necessary to multiply the content of the release agent by the compatibility ratio and then calculate and subtract the endothermic heat attributed to the release agent. The compatibility ratio is calculated by dividing the endothermic heat determined for a molten mixture of the resin components and the release agent in the same ratio as the content of the release agent by the theoretical endothermic heat calculated from the endothermic heat of the molten mixture determined in advance and the endothermic heat of the release agent alone. The endothermic heat is calculated using DSC analysis software from the endothermic heat from a temperature 20.0°C lower than the corresponding endothermic peak Tp to a temperature 10.0°C higher than Tp.
In addition, when there are multiple endothermic peaks derived from resin A, the peak temperature of the peak with the highest peak height is the "peak temperature of the largest endothermic peak," and the total endothermic amount of the multiple peaks is the "endothermic amount of the endothermic peaks derived from resin A."

<Measurement of Glass Transition Temperature>
The glass transition temperature Tg is measured in accordance with ASTM D3418-82 using a differential scanning calorimeter "Q2000" (manufactured by TA Instruments). The melting points of indium and zinc are used for temperature correction of the detector, and the heat of fusion of indium is used for heat quantity correction. Specifically, 2 mg of sample is precisely weighed and placed in an aluminum pan. An empty aluminum pan is used as a reference, and measurements are performed at a temperature rise rate of 10°C/min within a measurement temperature range of -10 to 200°C. Note that in the measurement, the temperature is raised to 200°C once, then lowered to -10°C, and then raised again. During this second heating process, the specific heat change is obtained in the temperature range of 30°C to 100°C. The intersection of the line midpoint between the baselines before and after the specific heat change appears and the differential heat curve is taken as the glass transition temperature Tg.

<Measurement of Weight Average Particle Size (D4) of Toner>
The weight average particle size (D4) of the toner is calculated as follows. The measuring device used is a precision particle size distribution measuring device using the narrow bore electrical resistance method, "Coulter Counter Multisizer 3" (registered trademark, manufactured by Beckman Coulter, Inc.), equipped with a 100 μm aperture tube. The measurement conditions are set and the measurement data is analyzed using the accompanying dedicated software, "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter, Inc.). The measurement is performed using an effective number of measurement channels of 25,000. The electrolytic solution used for the measurement is prepared by dissolving special-grade sodium chloride in ion-exchange water to a concentration of 1.0%, for example, "ISOTON II" (manufactured by Beckman Coulter, Inc.).

Before performing measurements and analysis, configure the dedicated software as follows. On the "Change Standard Measurement Method (SOMME)" screen of the dedicated software, set the total count in control mode to 50,000 particles, the number of measurements to 1, and the Kd value to the value obtained using a "10.0 μm standard particle" (manufactured by Beckman Coulter, Inc.). Press the "Threshold/Noise Level Measurement Button" to automatically set the threshold and noise level. Also, set the current to 1,600 μA, the gain to 2, the electrolyte to ISOTON II, and check "Flush aperture tube after measurement." On the "Pulse to Particle Size Conversion Settings" screen of the dedicated software, set the bin spacing to logarithmic particle size, the particle size bin to 256 particle size bins, and the particle size range from 2 μm to 60 μm. The specific measurement method is as follows:

(1) Pour 200.0 mL of the electrolyte solution into a 250 mL round-bottom glass beaker made specifically for the Multisizer 3, set it on the sample stand, and stir the stirrer rod counterclockwise at 24 revolutions per second. Then, use the "Aperture Tube Flush" function of the dedicated software to remove any dirt and air bubbles from inside the aperture tube.
(2) 30.0 mL of the aqueous electrolyte solution is placed in a 100 mL flat-bottom glass beaker, and 0.3 mL of a dilution of "Contaminon N" (a 10% aqueous solution of a neutral detergent for cleaning precision measuring instruments, pH 7, consisting of a nonionic surfactant, an anionic surfactant, and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) diluted 3 times by mass with ion-exchanged water is added as a dispersant.
(3) Prepare an ultrasonic disperser "Ultrasonic Dispersion System Tetra150" (manufactured by Nikkaki Bios Co., Ltd.) with an electrical output of 120 W and two built-in oscillators with an oscillation frequency of 50 kHz and a phase difference of 180 degrees. 3.3 L of ion-exchanged water is placed in the water tank of the ultrasonic disperser, and 2.0 mL of Contaminon N is added to this water tank.
(4) The beaker (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. Then, the height of the beaker is adjusted so that the resonance state of the liquid surface of the electrolytic solution in the beaker is maximized.
(5) While the electrolyte solution in the beaker in (4) is being irradiated with ultrasonic waves, 10 mg of toner particles are added little by little to the electrolyte solution and dispersed. The ultrasonic dispersion process is then continued for another 60 seconds. During the ultrasonic dispersion, the water temperature in the water tank is appropriately adjusted to be between 10°C and 40°C.
(6) Using a pipette, the electrolytic solution prepared in (5) above, in which toner particles have been dispersed, is dropped into the round-bottom beaker prepared in (1) above placed in the sample stand, and the measurement concentration is adjusted to 5%. Then, measurements are continued until the number of particles measured reaches 50,000.
(7) The measurement data is analyzed using the dedicated software provided with the device to calculate the weight-average particle size (D4). Note that when the dedicated software is set to graph/volume %, the "average diameter" on the "analysis/volume statistics (arithmetic mean)" screen is the weight-average particle size (D4).

<Measurement of Resin Acid Value>
The acid value is the mass (mg) of potassium hydroxide required to neutralize the acid contained in 1 g of sample. The acid value of resins such as Resin A and Resin B is measured in accordance with JIS K 0070-1992, and specifically, is measured according to the following procedure.
(1) Reagent Preparation: Dissolve 1.0 g of phenolphthalein in 90 mL of ethyl alcohol (95% by volume) and add ion-exchanged water to make 100 mL to obtain a phenolphthalein solution. Dissolve 7 g of special-grade potassium hydroxide in 5 mL of water and add ethyl alcohol (95% by volume) to make 1 L. Place the solution in an alkali-resistant container to avoid contact with carbon dioxide and leave for 3 days, then filter to obtain a potassium hydroxide solution. Store the resulting potassium hydroxide solution in an alkali-resistant container. The factor of the potassium hydroxide solution is determined by placing 25 mL of 0.1 mol/L hydrochloric acid in an Erlenmeyer flask, adding a few drops of the phenolphthalein solution, and titrating with the potassium hydroxide solution to determine the amount of potassium hydroxide solution required for neutralization. The 0.1 mol/L hydrochloric acid used is prepared in accordance with JIS K 8001-1998.

(2) Procedure (A) Main Test: 2.0 g of the crushed sample was accurately weighed into a 200 mL Erlenmeyer flask, and 100 mL of a toluene/ethanol (2:1) mixed solution was added and dissolved over 5 hours. Next, several drops of the phenolphthalein solution were added as an indicator, and the sample was titrated with the potassium hydroxide solution. The endpoint of the titration was when the light red color of the indicator persisted for 30 seconds.
(B) Blank Test: A titration is carried out in the same manner as above, except that no sample is used (i.e., only a mixed solution of toluene/ethanol (2:1) is used).
(3) The obtained results are substituted into the following formula to calculate the acid value.
A=[(CB)×f×5.61]/S
where A is the acid value (mg KOH/g), B is the amount (mL) of potassium hydroxide solution added for the blank test, C is the amount (mL) of potassium hydroxide solution added for the main test, f is the factor of the potassium hydroxide solution, and S is the sample (g).

<Method of calculating SP value>
The SP values of a monomer unit, such as SPa and SPc, are calculated according to the calculation method proposed by Fedors as follows: For an atom or atomic group in the molecular structure in which the double bond of each polymerizable monomer is cleaved by polymerization, the evaporation energy (Δei) (cal/mol) and molar volume (Δvi) (cm ³ /mol) are calculated from the table in "Polym. Eng. Sci., 14(2), 147-154 (1974)", and (4.184 × ΣΔei/ΣΔvi) ^0.5 is defined as the SP value (J/cm ³ ) ^0.5 .

On the other hand, the SP values SPA and SPB of a resin are calculated by determining the evaporation energy (Δei) and molar volume (Δvi) of each monomer unit constituting the resin, calculating the product of each monomer unit and the molar ratio (j) of each monomer unit in the resin, and dividing the sum of the evaporation energies of each unit by the sum of the molar volumes, using the following formula:
SPs={(Σj×ΣΔei)/(Σj×ΣΔvi)} ^1/2
As described above, the SP value is calculated for each resin, and the SP value unit can be converted to a unit of (cal/cm ³ ) ^0.5 by using 1 (cal/cm ³ ) ^0.5 = 2.045 (J/cm ³ ) ^0.5 .

The present invention will be explained in more detail below using examples, but these examples are not intended to limit the scope of the present invention in any way. In the following formulations, parts are by weight unless otherwise specified.

<Production Example of Resin B1>
The following materials were placed in a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere.
Solvent: toluene 100.0 parts, styrene 64.0 parts, behenyl acrylate 18.0 parts, acrylonitrile 15.0 parts, methacrylic acid 3.0 parts, polymerization initiator: t-butyl peroxypivalate (Perbutyl PV, manufactured by NOF Corporation) 5.0 parts. The reactor was heated to 70°C while stirring at 200 rpm and polymerization reaction was carried out for 12 hours to obtain a solution in which a polymer of the monomer composition was dissolved in toluene. Subsequently, the solution was cooled to 25°C, and then poured into 1000.0 parts of methanol while stirring to precipitate the methanol-insoluble matter. The obtained methanol-insoluble matter was filtered, washed with methanol, and then vacuum-dried at 40°C for 24 hours to obtain Resin B1. The physical properties of Resin B1 are shown in Table 1. Resin B1 was analyzed by NMR, and when mol% was converted to mass%, it was found to contain 64.0 mass% of monomer units polymerized from styrene, 18.0 mass% of monomer units polymerized from behenyl acrylate, 15.0 mass% of monomer units polymerized from acrylonitrile, and 3.0 mass% of monomer units polymerized from methacrylic acid.

<Production Examples of Resins B2 to B9, 12 to B18>
Resins B2 to B9 and 12 to B18 were obtained in the same manner as in the production method for Resin B1, except that the types and amounts of polymerizable monomers were changed as shown in Table 1. The physical properties are shown in Table 1.

<Production Example of Resin B10>
Resin B10 was obtained in the same manner as Resin B1, except that the amount of polymerization initiator t-butyl peroxypivalate was changed to 7.0 parts. The physical properties of Resin B10 are shown in Table 1.

<Production Example of Resin B11>
Resin B11 was obtained in the same manner as Resin B1, except that the amount of polymerization initiator t-butyl peroxypivalate was changed to 3.0 parts. The physical properties of Resin B11 are shown in Table 1.

When resins B2 to B18 were analyzed by NMR, it was confirmed that, like resin B1, each monomer unit was present in the same mass ratio as the monomer used.
In the table, the unit of the acid value is mgKOH/g, and the unit of the SP value is (J/cm ³ ) ^0.5 .

The following abbreviations are used in the table, including:
BeA: Behenyl acrylate (carbon number m = 22)
AN: Acrylonitrile MAA: Methacrylic acid St: Styrene StA: Stearyl acrylate (carbon number m = 17)
MiA: Myricyl acrylate (carbon number m = 29)
LaA: lauryl acrylate (carbon number m = 11)
DcA: decyl acrylate (carbon number m = 9)
HEMA: 2-hydroxyethyl methacrylate

<Production Example of Amorphous Resin 1>
Amorphous Resin 1 was obtained in the same manner as in the production method for Resin B1, except that the materials charged into the reaction vessel were changed as follows:
Solvent: toluene 100.0 parts; Styrene 64.0 parts; n-butyl acrylate 36.0 parts; Polymerization initiator: t-butyl peroxypivalate (Perbutyl PV, manufactured by NOF Corporation) 5.0 parts

<Production Example of Toner 1>
[Toner Production by Suspension Polymerization Method]
(Preparation of Toner Particles 1)
The following materials were charged into an attritor (manufactured by Nippon Coke Company).
Methacrylonitrile 28.8 parts Styrene 6.7 parts Ethyl methacrylate 12.5 parts Colorant Pigment Blue 15:3 6.0 parts Using zirconia beads having a diameter of 5 mm, dispersion was carried out at 200 rpm for 2 hours to obtain a raw material dispersion.

Separately, 735.0 parts of ion-exchanged water and 16.0 parts of trisodium phosphate dodecahydrate were added to a vessel equipped with a high-speed stirring device (Primix Corporation) and a thermometer, and the temperature was raised to 60°C while stirring at 12,000 rpm. Next, an aqueous calcium chloride solution prepared by dissolving 9.0 parts of calcium chloride dihydrate in 65.0 parts of ion-exchanged water was added to the vessel, and the mixture was stirred at 12,000 rpm for 30 minutes while maintaining the temperature at 60°C, yielding an aqueous medium in which a dispersion stabilizer containing hydroxyapatite was dispersed in water.

Subsequently, the raw material dispersion liquid was transferred to a container equipped with a stirrer and a thermometer, and the temperature was raised to 60° C. while stirring at 100 rpm. The following materials were then added thereto.
While maintaining the temperature at 60°C, the mixture was stirred at 100 rpm for 30 minutes, and then 5.0 parts of t-butyl peroxypivalate (Perbutyl PV, manufactured by NOF Corporation) was added as a polymerization initiator. The mixture was stirred for another minute, and then poured into the aqueous medium being stirred at 12,000 rpm with the high-speed stirrer. While maintaining the temperature at 60°C, stirring was continued for 20 minutes with the high-speed stirrer to obtain a granulation liquid.

The granulation liquid was transferred to a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube, and heated to 70°C while stirring at 150 rpm under a nitrogen atmosphere. A polymerization reaction was carried out at 150 rpm for 12 hours while maintaining the temperature at 70°C, yielding a toner particle dispersion. The resulting toner particle dispersion was cooled to 45°C while stirring at 150 rpm, and then heat-treated for 5 hours while maintaining the temperature at 45°C. After heat treatment, the mixture was cooled to 30°C, and while continuing to stir, dilute hydrochloric acid was added until the pH reached 1.5 to dissolve the dispersion stabilizer. The solids were then filtered, thoroughly washed with ion-exchanged water, and vacuum-dried at 30°C for 24 hours to yield toner particles 1 containing resin A1.

Resin A1' was obtained in the same manner as in the above-described method for producing toner particles 1, except that Pigment Blue 15:3, Resin B, and wax were not used. Resin A1' had a weight-average molecular weight (Mw) of 56,000, a melting point of 63°C, and an acid value of 0.0 mgKOH/g. NMR analysis of Resin A1' revealed that it contained 50.0% by mass of monomer units polymerized from behenyl acrylate, 30.0% by mass of monomer units polymerized from methacrylonitrile, 7.0% by mass of monomer units polymerized from styrene, and 13.0% by mass of monomer units polymerized from ethyl methacrylate. It was confirmed that Resin A' and Resin A obtained by separation from toner using the above-described method have similar physical properties. It was also confirmed that Resin B obtained by separation from toner using the above-described method have similar physical properties to Resin B1 used as a raw material.

To 100.0 parts of toner particles 1, 2.0 parts of silica fine particles (treated with dimethyl silicone, number average particle diameter of primary particles: 10 nm) were added as an external additive, and the mixture was mixed for 15 minutes at 3000 rpm using an FM mixer (manufactured by Nippon Coke & Engineering Co., Ltd.) to obtain toner 1.
Resin A and Resin B were separated from Toner 1 by the method described above, and the physical properties of each resin obtained were measured. The physical properties are shown in Table 5, and the evaluation results are shown in Table 6.

<Production Examples of Toners 2 to 30>
Toner particles 2 to 30 were obtained in the same manner as in the production example of toner 1, except that the types and amounts of monomers used, the type and amount of resin B, and the types and amounts of other additives were changed as shown in Table 2. Furthermore, external addition was carried out in the same manner as in toner 1 to obtain toners 2 to 30. The physical properties of the toners are shown in Table 5, and the evaluation results are shown in Table 6. Note that with regard to toner 28, resin A' was prepared in the same manner as resin A1' above, and its physical properties were measured to determine the physical properties of resin A.

In the table, the following abbreviations are used: Other abbreviations are the same as in Table 1.
MAN: methacrylonitrile VA: vinyl acetate AD: acrylamide

<Production Example of Toner 31>
(Production Example of Resin A31)
The following materials were placed in a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere.
Toluene 100.0 parts Behenyl acrylate 50.0 parts Methacrylonitrile 30.0 parts Ethyl methacrylate 13.0 parts Styrene 7.0 parts t-butyl peroxypivalate (Perbutyl PV manufactured by NOF Corporation) 0.5 parts

The reactor was heated to 70°C while stirring at 200 rpm and the polymerization reaction was carried out for 12 hours, yielding a solution in which the polymer of the monomer composition was dissolved in toluene. The resulting solution was then cooled to 25°C and poured into 1,000.0 parts of methanol while stirring, causing the methanol-insoluble matter to precipitate. The resulting methanol-insoluble matter was filtered off, washed with methanol, and vacuum-dried at 40°C for 24 hours to yield Resin A31.

[Toner production by pulverization method]
Resin A31 96.2 parts Resin B1 3.8 parts Colorant Pigment Blue 15:3 (manufactured by Dainichiseika Chemicals) 6.0 parts Wax Dipentaerythritol hexastearate 9.0 parts Charge control agent (LR147: manufactured by Nippon Carlit Co., Ltd.) 2.0 parts The above materials were pre-mixed in an FM mixer (manufactured by Nippon Coke & Engineering Co., Ltd.), and then melt-kneaded at 150 ° C. using a twin-screw kneading extruder (PCM-30 type manufactured by Ikegai Iron Works Co., Ltd.) to obtain a kneaded product. During the cooling process of the obtained kneaded product, a heat treatment was performed in which the product was held at 45 ° C. for 5 hours. The kneaded product after the heat treatment was coarsely pulverized with a hammer mill and then pulverized with a mechanical pulverizer (Turbo Kogyo Co., Ltd. T-250) to obtain a finely pulverized powder. The resulting finely pulverized powder was classified using a multi-division classifier utilizing the Coanda effect, to obtain toner particles 31 having a weight average particle size (D4) of 7.0 μm.

To 100.0 parts of toner particles 31, 2.0 parts of silica fine particles (hydrophobized with hexamethyldisilazane, primary particle number-average particle size: 10 nm) were added as an external additive, and the mixture was mixed at 3,000 rpm for 15 minutes using an FM mixer (manufactured by Nippon Coke & Engineering Co., Ltd.) to obtain toner 33. The physical properties of toner 31 are shown in Table 5, and the evaluation results are shown in Table 6.

<Production Example of Toner 32>
[Toner Production by Emulsion Aggregation Method]
(Preparation of Resin A31 Dispersion)
Toluene 300.0 parts Resin A31 100.0 parts The above materials were weighed and mixed, and Resin A31 was dissolved at 90 ° C to obtain a toluene solution. Separately, 5.0 parts of sodium dodecylbenzenesulfonate and 10.0 parts of sodium laurate were added to 700.0 parts of ion-exchanged water and heated to 90 ° C to obtain an aqueous solution. Next, the above toluene solution and aqueous solution were mixed and stirred at 7000 rpm using an ultra-high-speed stirring device T.K. Robomix (manufactured by Primix). Furthermore, the mixture was emulsified at a pressure of 200 MPa using a high-pressure impact disperser Nanomizer (manufactured by Yoshida Kikai Kogyo). After that, the toluene was removed using an evaporator, and the concentration was adjusted with ion-exchanged water to obtain a dispersion containing 20% by mass of Resin A31 fine particles. The 50% particle size (D50) based on volume distribution of the Resin A31 dispersion was measured and found to be 0.40 μm.

(Preparation of Resin B1 Dispersion)
The same procedure as in the preparation of the resin A31 dispersion was followed except that resin A31 was replaced with resin B1, to obtain a resin B1 dispersion containing 20% by mass of resin B1 fine particles. The 50% particle size (D50) based on volume distribution of the resin B1 dispersion was measured and found to be 0.38 μm.

(Preparation of Wax Dispersion 1)
Wax (dipentaerythritol hexastearate) 100.0 parts Anionic surfactant Neogen RK (manufactured by Daiichi Kogyo Seiyaku) 5.0 parts Ion-exchanged water 395.0 parts The above materials were placed in a mixing vessel equipped with a stirrer and heated to 90°C. Thereafter, the mixture was circulated through a Clearmix W Motion (manufactured by M Technique) and subjected to a dispersion treatment for 60 minutes. The dispersion treatment conditions were as follows:
Rotor outer diameter: 3cm
Clearance: 0.3 mm
Rotor rotation speed: 19,000 rpm
・Screen rotation speed: 19,000 rpm
After the dispersion treatment, the mixture was cooled to 40°C under cooling treatment conditions of a rotor rotation speed of 1000 rpm, a screen rotation speed of 0 rpm, and a cooling rate of 10°C/min, thereby obtaining a wax dispersion 1 containing 20% by mass of wax microparticles. The 50% particle size (D50) based on volume distribution of the wax microparticles was measured and found to be 0.15 µm.

(Preparation of Colorant Dispersion 1)
Colorant (Pigment Blue 15:3) 50.0 parts, anionic surfactant Neogen RK (manufactured by Dai-ichi Kogyo Seiyaku) 7.5 parts, ion-exchanged water 442.5 parts The above materials were weighed, mixed, dissolved, and dispersed for 1 hour using a high-pressure impact disperser Nanomizer (manufactured by Yoshida Kikai Kogyo) to obtain Colorant Dispersion 1 containing 10% by mass of colorant fine particles. The 50% particle size (D50) based on volume distribution of the colorant fine particles was measured and found to be 0.20 μm.

(Preparation of Toner 32)
The following materials were placed in a round stainless steel flask and mixed.
Resin A31 dispersion: 480.0 parts Resin B1 dispersion: 20.0 parts Wax dispersion 1: 45.0 parts Colorant dispersion 1: 60.0 parts Ion-exchanged water: 160.0 parts After mixing, the mixture was dispersed at 5000 rpm for 10 minutes using a homogenizer Ultra Turrax T50 (manufactured by IKA Corporation). 1.0% nitric acid aqueous solution was added, the pH was adjusted to 3.0, and then the mixture was heated to 58 ° C. using a stirring blade in a heated water bath while appropriately adjusting the rotation speed so that the mixture was stirred. The formed aggregated particles were appropriately confirmed, and when aggregated particles with a weight average particle size (D4) of 6.0 μm were formed, 5% sodium hydroxide aqueous solution was added and the pH was adjusted to 9.0. Then, while continuing stirring, the mixture was heated to 75 ° C. The aggregated particles were fused by holding at 75 ° C. for 1 hour.
Subsequently, the temperature was raised to 90°C, and the mixture was maintained at 90°C for 1 hour, and then maintained at 70°C for 3 hours, thereby carrying out a heat treatment. After the heat treatment, the mixture was cooled to 30°C, filtered and subjected to solid-liquid separation, and then washed with ion-exchanged water. After the washing was completed, the mixture was dried using a vacuum dryer, thereby obtaining toner particles 32 having a weight average particle size (D4) of 6.1 μm.

To 100.0 parts of toner particles 32, 2.0 parts of silica microparticles (treated with dimethyl silicone, number-average particle size of primary particles: 10 nm) were added as an external additive, and mixed for 15 minutes at 3,000 rpm using an FM mixer (manufactured by Nippon Coke and Engineering Co., Ltd.) to obtain toner 32. The physical properties of toner 32 are shown in Table 5, and the evaluation results are shown in Table 6.

<Production Examples of Comparative Resins B1, B3, B5, and B6>
Resin B1 was used except that the type and amount (parts by mass) of the polymerizable monomer were changed as shown in Table 3.
Comparative resins B1, B3, B5 and B6 were obtained in the same manner as in the production method of 1. The physical properties are shown in Table 3.

<Production Example of Comparative Resin B2>
The following materials were added to an autoclave equipped with a pressure reducing device, a water separating device, a nitrogen gas introducing device, a temperature measuring device and a stirring device.
Terephthalic acid 32.3 parts, bisphenol A-propylene oxide 2-mol adduct 67.7 parts, potassium titanium oxalate (catalyst) 0.02 parts. Subsequently, the reaction was carried out under a nitrogen atmosphere at 220°C under normal pressure until the desired molecular weight was reached. After cooling, the mixture was pulverized to obtain Comparative Resin B2. The physical properties of Comparative Resin B2 are shown in Table 3.

<Production Example of Comparative Resin B4>
The following raw materials were charged into a heated and dried two-necked flask while introducing nitrogen.
Polyoxypropylene (2.2)-2,2-bis(4-hydroxyphenyl)propane 30.0 parts Polyoxyethylene (2.2)-2,2-bis(4-hydroxyphenyl)propane 33.0 parts Terephthalic acid 21.0 parts Dodecenyl succinic acid 15.0 parts Dibutyltin oxide 0.1 parts After purging the system with nitrogen by reducing the pressure, the mixture was stirred at 215°C for 5 hours. Thereafter, the mixture was gradually heated to 230°C under reduced pressure while continuing to stir, and maintained at this temperature for an additional 2 hours. When the mixture reached a viscous state, it was air-cooled to stop the reaction, thereby synthesizing an amorphous resin, which is an amorphous polyester. The physical properties of Comparative Resin B4 are shown in Table 3.

The abbreviations in the table are as follows:
BPA-PO 2 mole adduct: bisphenol A-propylene oxide 2 mole adduct CeA: cetyl acrylate (carbon number 16)

<Production Examples of Comparative Toners 1, 2, 5 to 8>
Comparative toner particles 1, 2, and 5 to 8 were obtained in the same manner as in the production example of toner 1, except that the types and amounts of monomers used and the type and amount of comparative resin B were changed as shown in Table 4. Furthermore, external addition was carried out in the same manner as in toner 1, to obtain comparative toners 1, 2, and 5 to 8. The physical properties of the toners are shown in Table 5, and the evaluation results are shown in Table 6.

In the table, the number of comparative resin B indicates the number of the comparative resin used, and in comparative toners 7 and 8, resin B1 shown in Table 1 was used.
BMA: butyl methacrylate

<Production Example of Comparative Toner 3>
Behenyl acrylate 63.6 parts, butyl methacrylate 27.3 parts, 1,10-decanediol diacrylate (crosslinking agent) 0.7 parts, Pigment Blue 15:3 6.5 parts, aluminum salicylate compound 1.0 part, paraffin wax 9.0 parts (manufactured by Nippon Seiro: HNP-51, melting point 74°C)
Comparative Resin B3 (9.1 parts) Toluene (100.0 parts) A monomer mixture consisting of the above materials was prepared. 15 mm zirconia beads were added to this mixture, and the mixture was dispersed for 2 hours using an attritor (manufactured by Mitsui Miike Chemical Engineering Co., Ltd.) to obtain a monomer composition. Furthermore, 800 parts of ion-exchanged water and 15.5 parts of tricalcium phosphate were added to a container equipped with a high-speed stirring device TK-Homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), the rotation speed was adjusted to 15,000 rpm, and the mixture was heated to 70°C to form a dispersion medium system. 6.0 parts of t-butyl peroxypivalate, a polymerization initiator, was added to the monomer composition, and the mixture was then poured into the dispersion medium system. A granulation process was carried out for 20 minutes while maintaining a speed of 12,000 rpm using the high-speed stirring device. Thereafter, the high-speed stirring device was replaced with a propeller stirring blade, and polymerization was carried out for 10 hours while stirring at 150 rpm and maintaining a temperature of 70°C, followed by desolvation at 95°C for 5 hours.

The resulting toner particle dispersion was cooled to 20°C, and then dilute hydrochloric acid was added until the pH reached 1.5. The dispersion was then thoroughly washed with ion-exchanged water, filtered, and dried to obtain comparative toner particles 3. Further, the same external additions as for toner 1 were carried out to obtain comparative toner 3.

<Production Example of Comparative Toner 4>
Behenyl acrylate 63.1 parts, methacrylonitrile 20.7 parts, styrene 10.4 parts, polypropylene glycol diacrylate 1.9 parts (manufactured by Shin-Nakamura Chemical Co., Ltd., APG-400, molecular weight 536)
Pigment Blue 15:3 6.5 parts Di-t-butylaluminum salicylate 1.0 part Fischer-Tropsch wax 20.0 parts (manufactured by Nippon Seiro Co., Ltd.: HNP-51, melting point Tm: 74°C)
A mixture consisting of the above materials was prepared: 3.8 parts Comparative Resin B4; 100.0 parts Toluene. The mixture was placed in an attritor (manufactured by Nippon Coke Corporation) and dispersed for 2 hours at 200 rpm using 5 mm diameter zirconia beads to obtain a raw material dispersion. Meanwhile, 735.00 parts of ion-exchanged water and 16.00 parts of trisodium phosphate (12-hydrate) were added to a container equipped with a high-speed stirring device, a homomixer (manufactured by Primix Corporation), and a thermometer, and the temperature was raised to 60°C while stirring at 12,000 rpm. A calcium chloride aqueous solution prepared by dissolving 9.00 parts of calcium chloride (dihydrate) in 65.00 parts of ion-exchanged water was then added, and the mixture was stirred at 12,000 rpm for 30 minutes while maintaining the temperature at 60°C. 10% hydrochloric acid was added to the mixture to adjust the pH to 6.0, obtaining an aqueous medium containing a dispersion stabilizer.

The raw material dispersion was then transferred to a container equipped with a stirrer and thermometer, and heated to 60°C while stirring at 100 rpm. 8.00 parts of t-butyl peroxypivalate (Perbutyl PV, manufactured by NOF Corporation) was added as a polymerization initiator, and the mixture was stirred at 100 rpm for 5 minutes while maintaining the temperature at 60°C. It was then poured into the aqueous medium being stirred at 12,000 rpm with the high-speed stirrer. Stirring was continued at 12,000 rpm with the high-speed stirrer while maintaining the temperature at 60°C for 20 minutes, yielding a granulation liquid.

The granulation liquid was transferred to a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube, and heated to 70°C while stirring at 150 rpm under a nitrogen atmosphere. A polymerization reaction was carried out for 10 hours at 150 rpm while maintaining 70°C. The reflux condenser was then removed from the reaction vessel, and the reaction liquid was heated to 95°C. The toluene was then removed by stirring at 150 rpm for 5 hours while maintaining 95°C, thereby obtaining a toner particle dispersion. The resulting toner particle dispersion was cooled to 20°C while stirring at 150 rpm, and dilute hydrochloric acid was added to dissolve the dispersion stabilizer until the pH reached 1.5 while maintaining stirring. The solids were filtered, thoroughly washed with ion-exchanged water, and vacuum-dried at 40°C for 24 hours to obtain comparative toner particles 4. Further, the same external additions as for toner 1 were carried out, and comparative toner 4 was obtained. The physical properties of the toner are shown in Table 5, and the evaluation results are shown in Table 6.

<Production Example of Comparative Toner 9>
(Preparation of Comparative Resin A9 Particle Dispersion)
Styrene 300.0 parts Stearyl acrylate 700.0 parts Dodecyl mercaptan 6.0 parts Decanediol diacrylate 4.0 parts The above ingredients were mixed and dissolved, and the resulting solution was dispersed and emulsified in a flask with 20.0 parts of anionic surfactant Newlex Paste H (NOF Corporation) dissolved in 1300.0 parts of ion-exchanged water. While stirring for 10 minutes, 200.0 parts of ion-exchanged water containing 20.0 parts of ammonium persulfate was added, and nitrogen substitution was performed. The contents were heated to 70 ° C. and emulsion polymerization was carried out for 6 hours. The reaction solution was then cooled to room temperature to prepare a comparative resin A9 particle dispersion.

(Preparation of Comparative Resin B7 Particle Dispersion)
Styrene 300.0 parts, stearyl acrylate 700.0 parts, acrylic acid 20.0 parts, dodecyl mercaptan 12.0 parts, decanediol diacrylate 4.0 parts. The above ingredients were mixed and dissolved, and the resulting solution was dispersed and emulsified in a flask with 20.0 parts of anionic surfactant Newlex Paste H (manufactured by NOF Corporation) dissolved in 1300.0 parts of ion-exchanged water. While stirring for 10 minutes, 200.0 parts of ion-exchanged water containing 20.0 parts of ammonium persulfate was added, and the mixture was purged with nitrogen. The contents were heated to 70 ° C and emulsion polymerization was carried out for 6 hours. The reaction solution was then cooled to room temperature to prepare a comparative resin B7 particle dispersion. Comparative resin B7 was sampled from a portion of the dispersion and analyzed. Comparative resin B7 had an Mw of 16,800, an acid value of 18.0 mgKOH/g, an SP value of 20.2 (J/cm ³ ) ^0.5 , and a Tm of 56°C.

(Preparation of Colorant Dispersion)
Phthalocyanine pigment: 250 parts (PV FAST BLUE, manufactured by Dainichiseika Color & Chemicals Co., Ltd.)
Anionic surfactant: 20 parts (Neogen RK, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
Ion-exchanged water: 730 parts The above ingredients were mixed and dissolved, and then dispersed using a homogenizer (Ultra Turrax manufactured by IKA) to obtain a colorant dispersion.

(Preparation of Wax Particle Dispersion)
Polyethylene wax: 400 parts (Toyo Petrolite Co., Ltd.: Polywax 725)
Anionic surfactant: 20 parts (Nurex R, manufactured by Nippon Oil & Fats Co., Ltd.)
Ion-exchanged water: 580 parts The above ingredients were mixed and dissolved, and then dispersed using a homogenizer (Ultra Turrax, manufactured by IKA Corporation), and then dispersed using a pressure discharge homogenizer to prepare a wax particle dispersion in which wax particles (polyethylene wax) were dispersed.

(Production of Comparative Toner Particles 9)
Comparative resin A9 particle dispersion 900.0 parts Comparative resin B7 particle dispersion 225.0 parts Colorant particle dispersion 100.0 parts Wax particle dispersion 63.0 parts Aluminum sulfate 5.0 parts (manufactured by Wako Pure Chemical Industries, Ltd.)
The above mixture (1000.0 parts of ion-exchanged water) was placed in a round stainless steel flask, adjusted to pH 2.0, and dispersed using a homogenizer (Ultra Turrax T50, manufactured by IKA Corporation). The mixture was then heated to 64°C with stirring in a heating oil bath. After maintaining the mixture at 61°C for 3 hours, observation with an optical microscope confirmed the formation of aggregated particles with an average particle size of approximately 5.0 μm. After further maintaining the mixture at 61°C with stirring for 4 hours, observation with an optical microscope confirmed the formation of aggregated particles with an average particle size of approximately 5.4 μm. The pH of these aggregated particles was 2.5. An aqueous solution of sodium bicarbonate (manufactured by Wako Pure Chemical Industries, Ltd.) diluted to 0.5% by weight was then added to adjust the pH to 7.2. The mixture was then heated to 90°C with continued stirring and maintained for 6 hours. The reaction product was then filtered, thoroughly washed with ion-exchanged water, and dried using a vacuum dryer to obtain comparative toner particles 9. The average particle size of the resulting comparative toner particles 9 was 5.5 μm. Furthermore, the same external addition as in Example 1 was carried out to obtain Comparative Toner 9. Table 5 shows the physical properties of the toner, and Table 6 shows the evaluation results.

In the table, the unit of the acid value is mgKOH/g, and the unit of the SP value is (J/cm ³ ) ^0.5 .

The evaluation of the toner will be described below.
<Evaluation of Low-Temperature Fixability of Toner>
To evaluate the low-temperature fixability of the toner, a modified laser beam printer (product name: LBP-7700C, manufactured by Canon Inc.) was used as the image forming device. The modifications to the modified machine were that it could operate even when the fixing unit was removed, and that the fixing temperature could be freely set. The paper used to output the image was rough paper, Fox River.
The toner was Bond (110 g/m ² ) manufactured by Fox River. First, the toner was removed from the cartridge and cleaned with an air blower. Then, 300 g of toner was filled into the cartridge. The cartridge was then left for 48 hours in an environment of 25°C temperature and 40% RH (N/N environment), and then installed in the cyan station of the printer under this environment, with dummy cartridges installed in the other stations. Evaluations were then conducted under the same environment as above.

Next, using the image forming apparatus with the fuser removed, an unfixed image of an image pattern was output in which a 10 mm x 10 mm square image was transferred to nine points, which were the intersections of the lines dividing the long and short sides of the paper into quarters. The toner coverage on the paper was 0.80 mg/ ^cm² . Using the fuser removed, the process speed was set to 250 mm/s, and the initial temperature was 90°C, and the set temperature was gradually increased by 5°C increments. The unfixed image was fixed at each temperature, obtaining fixed images at each temperature. A load of 50 g/ ^cm² was applied to the resulting fixed image, and it was rubbed back and forth five times with Silbon paper [Lenz Cleaning Paper "dasper®" (Ozu Paper Co. Ltd.)]. The image density was measured before and after rubbing, and the temperature at which the decrease in image density after rubbing relative to the image density before rubbing was 20% or less was defined as the fixing start temperature, and this value was used to evaluate the low-temperature fixability of the toner. A grade of C or higher was considered to be good. The evaluation results are shown in Table 6.
A: Fixing start temperature is 100°C or less B: Fixing start temperature is 105°C or more and 110°C or less C: Fixing start temperature is 115°C or more and 120°C or less D: Fixing start temperature is 125°C or more

<Evaluation of Toner Durability>
Durability evaluation was performed using a commercially available Canon printer LBP-712Ci. The toner contained in the commercially available cartridge was removed, the interior was cleaned with an air blower, and then 200 g of the above toner was filled into the cartridge for evaluation. The cartridge was left for 48 hours in an environment of 25°C and 40% RH, and then installed in the cyan station to evaluate durability. At this time, dummy cartridges were installed in the stations for the other colors.

Under an environment of 25°C and 40% RH, 20,000 sheets of horizontal line pattern images with a printing rate of 1% were continuously printed using Canon Oce Red Label (80 g/ ^m2 ). Solid images and halftone images were then printed, and the presence or absence of circumferential streaks caused by toner fusion to the regulating member, so-called development streaks, was visually confirmed. A grade of C or higher was considered good. The evaluation results are shown in Table 6.
A: No development streaks occur. B: Development streaks occur in 1 to 2 places. C: Development streaks occur in 3 to 4 places. D: Development streaks occur in 5 or more places.

<Evaluation of folding resistance of images with a large amount of toner loaded>
The bending resistance was evaluated using a commercially available Canon LBP-712Ci printer. The process cartridge filled with toner was left in an environment of 25°C and 40% RH for 48 hours. Using the printer, two 50 mm x 50 mm solid images with a toner loading of 1.0 mg/ ^cm2 were printed in the center of transfer paper at the above-mentioned fixing start temperature + 10°C.

One sheet of transfer paper was folded so that the valley fold lines formed the diagonal of the solid image, and the mountain fold lines formed a cross that bisected each side of the transferred image. The folding operation was performed three times. A soft thin paper (trade name "Dusper", manufactured by Ozu Sangyo Co., Ltd.) was rubbed five times back and forth while applying a load of 4.9 kPa. Image density was measured with the intersection of the four fold lines as the center. The other sheet was not folded, but was subjected only to the above-mentioned rubbing operation, and the image density was measured with the center of the solid image as the center. The image densities of the folded and unfolded transfer paper were compared, and the density reduction rate was evaluated. A grade of C or higher was determined to be good.
A: The density reduction rate is less than 5.0%. B: The density reduction rate is 5.0% or more and less than 8.0%. C: The density reduction rate is 8.0% or more and less than 10.0%. D: The density reduction rate is 10.0% or more.

<Evaluation of folding resistance of images with a small amount of toner loaded>
The bending resistance was evaluated using a commercially available Canon LBP-712Ci printer. The process cartridge filled with toner was left in an N/N environment for 48 hours. Using the printer, ^two 50 mm x 50 mm solid images with a toner loading of 0.3 mg/cm2 were printed in the center of transfer paper at the above-mentioned fixing start temperature + 10°C.

One sheet of transfer paper was folded so that the valley fold lines formed the diagonal of the solid image, and the mountain fold lines formed a cross that bisected each side of the transferred image. The folding operation was performed three times. A soft thin paper (trade name "Dusper", manufactured by Ozu Sangyo Co., Ltd.) was rubbed five times back and forth while applying a load of 4.9 kPa. Image density was measured with the intersection of the four fold lines as the center. The other sheet was not folded, but was subjected only to the above-mentioned rubbing operation, and the image density was measured with the center of the solid image as the center. The image densities of the folded and unfolded transfer paper were compared, and the density reduction rate was evaluated. A grade of C or higher was determined to be good.
A: The density reduction rate is less than 7.0%. B: The density reduction rate is 7.0% or more and less than 9.0%. C: The density reduction rate is 9.0% or more and less than 12.0%. D: The density reduction rate is 12.0% or more.

<Evaluation of Heat-Resistant Storage Stability of Toner>
Six grams of toner was placed in a 100 mL resin cup and left for 10 days in an environment with a temperature of 50°C and a humidity of 20% RH. The degree of cohesion of the left toner was then measured as follows. The measuring device used was a "Powder Tester" (manufactured by Hosokawa Micron Corporation) equipped with a digital display vibrometer "Digivro Model 1332A" (manufactured by Showa Sokki Co., Ltd.) connected to the side of the vibration table. A sieve with a mesh size of 38 μm (400 mesh), a sieve with a mesh size of 75 μm (200 mesh), and a sieve with a mesh size of 150 μm (100 mesh) were placed on top of each other on the vibration table of the powder tester. The measurement was performed in an environment with a temperature of 23°C and a humidity of 20% RH according to the following procedure.

(1) The vibration amplitude of the vibration table was adjusted in advance so that the displacement value on the digital display vibrometer was 0.60 mm (peak-to-peak).
(2) The toner that had been left for 10 days as described above was then left for 24 hours in an environment of 23° C. and 60% RH, and 5 g of the toner was precisely weighed out and gently placed on the top sieve with 150 μm openings.
(3) After vibrating the sieves for 15 seconds, the mass of the toner remaining on each sieve was measured, and the degree of cohesion (%) was calculated using the following formula. The evaluation results are shown in Table 6. A grade of C or higher was considered to be good.
Cohesion degree (%) =
{(mass of sample on a sieve with 150 μm openings (g))/5 (g)}×100
+ {(mass of sample on sieve with 75 μm openings (g))/5 (g)} × 100 × 0.6
+ {(mass of sample on sieve with 38 μm openings (g))/5 (g)} × 100 × 0.2
A: Cohesion degree is less than 20%. B: Cohesion degree is 20% or more but less than 25%. C: Cohesion degree is 25% or more but less than 30%. D: Cohesion degree is 30% or more.

The evaluation results for each toner are shown in Table 6.

Claims (14)

A toner having toner particles having a binder resin,
The binder resin contains resin A and resin B,
In differential scanning calorimetry using the toner as a sample, an endothermic peak derived from the resin A is observed, the peak top temperature of the largest endothermic peak is in the range of 50.0°C to 90.0°C, and the endothermic amount of the endothermic peak derived from the resin A is 30 J/g to 70 J/g per 1 g of the toner,
the content of the resin A in the toner particles is 60.0% by mass to 90.0% by mass,
The resin A contains 40.0% by mass to 70.0% by mass of a monomer unit (a) represented by the following formula (1),
The toner is characterized in that the resin B contains 5.0% by mass to 30.0% by mass of a monomer unit (b) represented by the following formula (2):
[In formula (1), ^R1 represents a hydrogen atom or a methyl group, and n represents an integer of 15 to 31. In formula (2), ^R2 represents a hydrogen atom or a methyl group, and m represents an integer of 9 to 31.] The toner according to claim 1, wherein the absolute value of the difference between n in formula (1) and m in formula (2), |n-m|, is 10 or less. The toner according to claim 1 or 2, wherein the content of resin B in the toner particles is 1.0% by mass to 20.0% by mass. the resin A has a monomer unit (c) different from the monomer unit (a),
When the SP value of the monomer unit (a) is SPa and the SP value of the monomer unit (c) is SPc, the following formula (3) is satisfied:
4. The toner according to claim 1, wherein the content of the monomer unit (c) satisfying the following formula (3) in the resin A is 20.0% by mass or more:
3.0≦(SPc-SPa)≦25.0...(3)
The toner according to claim 4, wherein the monomer unit (c) is represented by the following formula (4):
[In formula (4), ^R3 represents a hydrogen atom or a methyl group] The toner according to any one of claims 1 to 5, wherein the weight-average molecular weight MwB of the tetrahydrofuran-soluble portion of Resin B, as measured by gel permeation chromatography, is 10,000 to 20,000. The acid value AvB of the resin B is 5.0 mgKOH/g to 30.0 mgKOH/g,
7. The toner according to claim 1, wherein the difference (AvB-AvA) between the acid value AvA of the resin A and the acid value AvB of the resin A is 5.0 mgKOH/g or more. The toner according to any one of claims 1 to 7, wherein the acid value AvA of the resin A is 5.0 mgKOH/g or less. The toner according to any one of claims 1 to 8, wherein when the SP value of the resin A is SPA (J/cm ³ ) ^0.5 and the SP value of the resin B is SPB (J/cm ³ ) ^0.5 , the absolute value of the difference between SPA and SPB satisfies the following formula (5):
0.2≦｜SPA-SPB｜≦2.0...(5) The toner according to any one of claims 1 to 9, wherein the glass transition temperature TgB of resin B is 30.0°C to 90.0°C. The toner according to any one of claims 1 to 10, wherein resin B contains 5.0% by mass to 25.0% by mass of the monomer unit (b) represented by formula (2). The toner according to any one of claims 1 to 11, wherein the total content of resin A and resin B in the binder resin is 80.0% by mass or more. The resin A is a crystalline resin having a clear endothermic peak in differential scanning calorimetry,
13. The toner according to claim 1, wherein the resin B is a resin that does not have a clear endothermic peak in differential scanning calorimetry. A method for producing a toner having toner particles containing a binder resin, comprising:
The binder resin contains resin A and resin B,
The resin A contains 40.0% by mass to 70.0% by mass of a monomer unit (a) represented by the following formula (1):
The resin B contains 5.0% by mass to 30.0% by mass of a monomer unit (b) represented by the following formula (2):
The manufacturing method comprises:
a step of preparing a polymerizable monomer composition containing a polymerizable monomer capable of forming the resin A and the resin B; and a step of polymerizing the polymerizable monomer contained in the polymerizable monomer composition to obtain the toner particles.
[In formula (1), ^R1 represents a hydrogen atom or a methyl group, and n represents an integer of 15 to 31. In formula (2), ^R2 represents a hydrogen atom or a methyl group, and m represents an integer of 9 to 31.]