JP7555811B2 - toner - Google Patents

Description

The present invention relates to a toner used in electrophotography, electrostatic recording, electrostatic printing, toner jet, etc.

In recent years, as full-color electrophotographic copiers have become more widespread, there has been a demand for additional performance improvements, such as energy saving performance, shorter recovery time from sleep mode, and compatibility with a wide variety of media, in addition to higher speed and higher image quality.
Specifically, as a toner that meets the demand for energy saving, a toner that can be fixed at a lower temperature and has excellent low-temperature fixability is required in order to reduce power consumption in the fixing step.
In addition, thick coated paper, which is one of the various media, contains a large amount of inorganic fine particles such as calcium carbonate to increase the whiteness, so that the friction coefficient due to rubbing between sheets of paper becomes large, and the toner of the fixed image is easily peeled off from the paper. Therefore, there is a demand for a toner with excellent abrasion resistance that does not peel off even when sheets of thick coated paper are rubbed against each other.

JP 2018-151619 A

The toner described in Patent Document 1 uses a crystalline polyvinyl resin having sharp melting properties, and therefore has excellent low-temperature fixing properties. On the other hand, the crystalline polyvinyl resin has a small polarity difference with the release agent and a high affinity, so that the exudation of the release agent is suppressed and a layer of the release agent is unlikely to be formed on the surface of the fixed image. For these reasons, even if the toner described in Patent Document 1 is used, the abrasion resistance required in recent years may be inferior in some cases.
The present invention has been made in consideration of the above problems, and provides a toner that not only exhibits excellent low-temperature fixing property, but also exhibits excellent abrasion resistance even in images fixed onto media containing a large amount of inorganic fine particles, such as thick coated paper.

The toner according to the present invention is a toner having toner particles containing a binder resin and a release agent,
The binder resin contains a crystalline resin,
The crystalline resin has a first monomer unit represented by the following formula (1):
a ratio of the first monomer unit in the crystalline resin is 30.0% by mass to 100.0% by mass based on the total mass of all monomer units in the crystalline resin;

[In formula (1), R _Z1 represents a hydrogen atom or a methyl group, and R ¹ represents an alkyl group having 18 to 36 carbon atoms.]
The release agent contains an α-olefin polymer having a monomer unit represented by the following formula (2):

[In formula (2), R ² represents an alkyl group having 18 to 36 carbon atoms.]
The toner has a maximum endothermic peak temperature of the α-olefin polymer of 40° C. to 90° C. as measured by a differential scanning calorimeter (DSC).

According to one aspect of the present invention, it is possible to provide a toner that has excellent low-temperature fixing properties and abrasion resistance when fixed onto thick coated paper or the like.

In the present invention, the expressions "xx or more and xx or less" and "xx to xx" expressing a numerical range mean a numerical range including the endpoints, that is, the lower limit and the upper limit, unless otherwise specified.
In the present invention, the (meth)acrylic acid ester means an acrylic acid ester and/or a methacrylic acid ester.
In the present invention, the term "monomer unit" refers to one section of a carbon-carbon bond in the main chain of a polymer formed by polymerization of a vinyl monomer. The vinyl monomer can be represented by the following formula (Z).

[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 arbitrary substituent.]
The crystalline resin refers to a resin that shows a clear endothermic peak in a differential scanning calorimeter (DSC) measurement.
Hereinafter, an embodiment of the present invention will be described in detail.

The toner according to the present invention is a toner having toner particles containing a binder resin and a release agent,
The binder resin contains a crystalline resin,
The crystalline resin has a first monomer unit represented by the following formula (1):
The proportion of the first monomer unit in the crystalline resin is 30.0% by mass to 100.0% by mass based on the total mass of all monomer units in the crystalline resin.

[In formula (1), R _Z1 represents a hydrogen atom or a methyl group, and R ¹ represents an alkyl group having 18 to 36 carbon atoms.]
The release agent contains an α-olefin polymer having a monomer unit represented by the following formula (2):

［式（２）中、Ｒ^２は、炭素数１８～３６のアルキル基を表す。］
示差走査熱量計（ＤＳＣ）により測定される該α－オレフィン重合体の最大吸熱ピーク温度が、４０℃～９０℃である。
本発明に係るトナーによれば、低温定着性と厚紙コート紙などにおける耐擦過性とを両立するトナーを提供することができる。

[In formula (2), R ² represents an alkyl group having 18 to 36 carbon atoms.]
The α-olefin polymer has a maximum endothermic peak temperature of 40° C. to 90° C. as measured by differential scanning calorimetry (DSC).
According to the toner of the present invention, it is possible to provide a toner that has both low-temperature fixability and abrasion resistance on thick coated paper and the like.

The present inventors conducted extensive research and found that the above-mentioned problems can be solved by controlling the composition of the monomer units of the crystalline resin, the composition of the monomer units of the release agent, the maximum endothermic peak temperature measured by a differential scanning calorimeter (DSC), and the like, and thus arrived at the present invention.
The present inventors speculate that the reason for solving the above problem is as follows.
The reason why the abrasion resistance is poor when the crystalline resin is used is that the crystalline resin and the release agent are compatible with each other, making it difficult for a layer of the release agent to be formed on the surface of the fixed image. The reason why the crystalline resin is compatible with the release agent is that the absolute value of the polarity difference between the crystalline material and the release agent is small. On the other hand, if the crystalline resin is made highly polar indiscriminately, the crystallinity of the crystalline resin will be destroyed, leading to a decrease in low-temperature fixability.

The present inventors have discovered that adding a release agent containing an α-olefin monomer unit to the crystalline resin can improve sharp melt properties, provide excellent low-temperature fixability, and form a strong film on the surface of the fixed image, resulting in excellent abrasion resistance. As a result of detailed investigation, it was found that the relationship between the carbon number of the crystalline resin and the carbon number of the release agent has a large effect, leading to the present invention. When the release agent containing an α-olefin monomer unit having an alkyl group with 18 to 36 carbon atoms and the crystalline material having an alkyl group with 18 to 36 carbon atoms are used, the two have side chain structures with similar carbon numbers. For this reason, it was found that the release agent promotes the crystallinity of the crystalline resin, improves sharp melt properties and provides excellent low-temperature fixability, and because of the strong interaction between the two, a strong film is formed on the surface of the fixed image, resulting in excellent abrasion resistance.
The term "α-olefin monomer unit having an alkyl group with 18 to 36 carbon atoms" means that the alkyl group in the α-olefin monomer unit has 18 to 36 carbon atoms.

The toner according to the present invention contains a binder resin having a crystalline resin, and a release agent.
The crystalline resin according to the present invention has a first monomer unit represented by the above formula (1). The first monomer unit represented by the above formula (1) is derived from a first polymerizable monomer which is at least one selected from the group consisting of (meth)acrylic acid esters having an alkyl group having 18 to 36 carbon atoms.

When the first monomer unit is a (meth)acrylic acid ester having an alkyl group having 18 to 36 carbon atoms, it is possible to impart crystallinity to the resin, and therefore the toner exhibits sharp melting properties and excellent low-temperature fixing properties.
Examples of (meth)acrylic acid esters having an alkyl group having 18 to 36 carbon atoms include the following: (meth)acrylic acid esters having a linear alkyl group having 18 to 36 carbon atoms [stearyl (meth)acrylate, nonadecyl (meth)acrylate, eicosyl (meth)acrylate, heneicosanyl (meth)acrylate, behenyl (meth)acrylate, lignoceryl (meth)acrylate, ceryl (meth)acrylate, octacosa (meth)acrylate, myricyl (meth)acrylate, dotriacontane (meth)acrylate, etc.] and (meth)acrylic acid esters having a branched alkyl group having 18 to 36 carbon atoms [2-decyltetradecyl (meth)acrylate, etc.].

Among these, from the viewpoint of excellent low-temperature fixing property, at least one selected from the group consisting of (meth)acrylic acid esters having a linear alkyl group with 18 to 36 carbon atoms is preferable. Also, at least one selected from the group consisting of (meth)acrylic acid esters having a linear alkyl group with 18 to 30 carbon atoms is more preferable, and behenyl (meth)acrylate in which the linear alkyl group has 22 carbon atoms is even more preferable.
The polymerizable monomer derived from the first monomer unit represented by the above formula (1) may be used alone or in combination of two or more kinds.

The proportion of the first monomer unit in the crystalline resin according to the present invention is 30.0% by mass to 100.0% by mass based on the total mass of all monomer units in the crystalline resin.
When the ratio of the first monomer unit is from 30.0% by mass to 100.0% by mass, the toner exhibits sharp melting properties due to crystallinity, and excellent low-temperature fixing properties are obtained.
The proportion of the first monomer unit is preferably 30.0% by mass to 80.0% by mass, and more preferably 30.0% by mass to 60.0% by mass, from the viewpoint of obtaining excellent charge retention.
In addition, when the crystalline resin has monomer units derived from two or more types of (meth)acrylic acid esters having alkyl groups having 18 to 36 carbon atoms, the content of the first monomer unit represents the mass ratio of the total of these monomer units.

The crystalline resin according to the present invention preferably has a second monomer unit represented by the following formula (3) or (4) which is different from the first monomer unit.
When the SP value of the second monomer unit is SP2 (J/cm ³ ) ^0.5 , it is preferable that the following relational expression (5) is satisfied: It is more preferable that the following relational expression (5)' is satisfied.
21.00 (J/ ^cm3 ) ^0.5 ≦SP2...(5)
25.00 (J/ ^cm3 ) ^0.5 ≦SP2...(5)'
The SP value is an abbreviation for solubility parameter, and is a value that serves as an index of solubility. The calculation method will be described later.
In the present invention, the unit of the SP value is (J/cm ³ ) ^0.5 , but it can be converted to a unit of (cal/cm ³ ) ^0.5 by 1 (cal/cm ³ ) ^0.5 = 2.045 × 10 ³ (J/cm ³ ) ^0.5 .

By satisfying the above relational expression (5), the second monomer unit becomes highly polar, and a polarity difference occurs between the first and second monomer units. Such a polarity difference promotes the crystallization of the first monomer unit, resulting in excellent low-temperature fixability. Specifically, the first monomer unit is incorporated into a crystalline resin, and the first monomer units aggregate with each other to exhibit crystallinity. In normal cases, the crystallization of the first monomer unit is inhibited when other monomer units are incorporated, making it difficult for the crystalline resin to exhibit crystallinity. This tendency becomes more pronounced when multiple types of monomer units are randomly bonded to each other within one molecule of the crystalline resin. However, by using a first polymerizable monomer and a second polymerizable monomer having a polarity difference, it is thought that the first polymerizable monomer and the second polymerizable monomer can be bonded to a certain extent continuously during polymerization, rather than being randomly bonded. As a result, a block in which the first monomer units are aggregated with each other is formed, and the crystalline resin becomes a block copolymer, making it possible to increase crystallinity even when other monomer units are incorporated, resulting in excellent low-temperature fixability. Furthermore, the highly polar moieties are preferable because they can form a pseudo-crosslinked structure with the polar groups in the paper, resulting in excellent abrasion resistance.

(In the formula, X represents a single bond or an alkylene group having 1 to 6 carbon atoms,
^R3 is
A nitrile group (—C≡N),
an amide group (-C(=O)NHR ¹⁰ (R ¹⁰ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms);
Hydroxy groups,
-COOR ³¹ (R ³¹ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a hydroxyalkyl group having 1 to 6 carbon atoms),
a urea group (-NH-C(=O)-N( ^R33 ) ₂ (each ^R33 independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms);
-COO( _CH2 ) _2NHCOOR34 ( ^{wherein R34} represents an alkyl group having 1 to 4 carbon atoms), or -COO( _CH2 ) ₂ -NH-C(=O)-N( ^R35 ) ₂ (wherein ^R35 each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms).
represents
^R4 represents a hydrogen atom or a methyl group.

(In the formula, R ⁵ represents an alkyl group having 1 to 4 carbon atoms,
^R6 represents a hydrogen atom or a methyl group.

Specifically, as the second monomer unit, for example, among the polymerizable monomers listed below, a polymerizable monomer that satisfies the above-mentioned relational formula (5) can be used.
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 (acrylic acid, methacrylic acid, etc.) having an ethylenically unsaturated bond by a known method.

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

Among these, it is preferable to use a monomer having a nitrile group, an amide group, a hydroxy group, or a urea group. More preferably, it is a monomer having at least one functional group selected from the group consisting of a nitrile group, an amide group, a hydroxy group, and a urea group, and an ethylenically unsaturated bond. Acrylonitrile and methacrylonitrile are particularly preferable.

The following are also preferably used as the second monomer unit: vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl caprylate, vinyl caprate, vinyl laurate, vinyl myristate, vinyl palmitate, vinyl stearate, vinyl pivalate, vinyl octylate, etc. Among these, vinyl esters are preferred from the viewpoint of obtaining excellent low-temperature fixability, since they are non-conjugated monomers and therefore tend to maintain a suitable reactivity with the first polymerizable monomer and tend to increase the crystallinity of the polymer.
The proportion of the second monomer unit is preferably from 10.0% by mass to 70.0% by mass, and more preferably from 30.0% by mass to 50.0% by mass.

The crystalline resin according to the present invention may contain a third monomer unit derived from a third polymerizable monomer not included in the range of the above-mentioned relational formula (5) within a range that does not impair the mass ratio of the above-mentioned first monomer unit and second monomer unit. The third polymerizable monomer means a polymerizable monomer different from the first polymerizable monomer and the second polymerizable monomer.
As the third polymerizable monomer, among the monomers exemplified as the second polymerizable monomer, a monomer that does not satisfy the above relational formula (5) can be used.

For example, the following monomers can also be used:
Styrene and its derivatives such as styrene and o-methylstyrene, and (meth)acrylic acid esters such as methyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Among these, the third polymerizable monomer is preferably styrene. Styrene is preferable from the viewpoint of obtaining excellent abrasion resistance because it has an effect of reducing compatibility with the release agent due to steric hindrance of the aromatic ring of styrene, and a larger layer of the release agent is formed on the surface of the fixed image.
The proportion of the third monomer unit is preferably from 5.0% by mass to 40.0% by mass, and more preferably from 10.0% by mass to 20.0% by mass.

The weight average molecular weight (Mw) of the THF-soluble portion of the crystalline resin, as measured by gel permeation chromatography (GPC), is preferably 10,000 to 200,000, and more preferably 20,000 to 150,000. Having an Mw within the above range is preferable because it makes it easier to maintain elasticity at around room temperature. THF stands for tetrahydrofuran.

The melting point of the crystalline resin is preferably 50°C to 80°C, and more preferably 53°C to 70°C. When the melting point of the crystalline resin is within the above range, it exhibits better low-temperature fixing properties. The melting point of the crystalline resin can be adjusted by the type and amount of the first polymerizable monomer and the type and amount of the second polymerizable monomer used.

The crystalline resin is preferably a vinyl polymer. Examples of vinyl polymers include polymers of monomers containing ethylenically unsaturated bonds. Ethylenically unsaturated bonds refer to carbon-carbon double bonds capable of radical polymerization, and examples of such groups include vinyl groups, propenyl groups, acryloyl groups, and methacryloyl groups.

The release agent according to the present invention contains an α-olefin polymer having a monomer unit represented by the above formula (2), where ^R2 represents an alkyl group having 18 to 36 carbon atoms.

When the monomer unit of the above formula (2) has an alkyl group having 18 to 36 carbon atoms, the crystallization of the crystalline resin is promoted, thereby providing excellent low-temperature fixing properties, and the interaction between the two is prominent, so that a strong layer is formed on the surface of the fixed image, providing excellent abrasion resistance.
Examples of α-olefins having an alkyl group having 18 to 36 carbon atoms include the following: 1-icosene, 1-docosene, 1-tetracosene, 1-hexacosene, 1-octacosene, 1-triacontene, 1-dotriacontene, 1-tetratriacontene, 1-hexatriacontene, etc. These α-olefins may be used alone or in combination of two or more kinds.

The release agent according to the present invention preferably has an "α-olefin monomer unit having an alkyl group with less than 18 carbon atoms" different from the "α-olefin monomer unit having an alkyl group with 18 to 36 carbon atoms of the above formula (2)". The presence of an α-olefin monomer unit with a short carbon number between the α-olefin monomer units having an alkyl group with 18 to 36 carbon atoms can suppress entanglement between the α-olefin monomer units having an alkyl group with 18 to 36 carbon atoms. As a result, the interaction between the α-olefin monomer unit having an alkyl group with 18 to 36 carbon atoms and the release agent is further promoted, resulting in excellent low-temperature fixability and excellent abrasion resistance. Examples of α-olefins having an alkyl group with less than 18 carbon atoms include ethylene, 1-butene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, and 1-octadecene.

The release agent according to the present invention has a maximum endothermic peak temperature derived from the α-olefin polymer of 40°C to 90°C as measured by a differential scanning calorimeter (DSC). When the maximum endothermic peak temperature is 40°C to 90°C, a sufficient film of the release agent is formed on the surface of the fixed image, resulting in excellent abrasion resistance. The maximum endothermic peak temperature is preferably 50°C to 80°C.

The release agent according to the present invention preferably has a weight average molecular weight Mw of 1,000 to 10,000.
When the weight average molecular weight Mw is 1,000 to 10,000, a larger film of the release agent is formed on the surface of the fixed image while suppressing compatibility with the crystalline resin, and therefore the abrasion resistance is excellent. The weight average molecular weight Mw of the release agent is more preferably 3,000 to 8,000.

The content of the release agent according to the present invention is preferably 1.0 part by mass to 20.0 parts by mass with respect to 100 parts by mass of the crystalline resin.
When the content of the release agent is 1.0 parts by mass to 20.0 parts by mass relative to 100 parts by mass of the crystalline resin, the crystallinity of the crystalline resin is promoted, the low-temperature fixing property is improved, and a larger film of the release agent is formed on the surface of the fixed image, resulting in excellent abrasion resistance. The content of the release agent is more preferably 5.0 parts by mass to 15.0 parts by mass relative to 100 parts by mass of the crystalline resin.

The ratio of the carbon number of R ² in the above formula (2) to the carbon number of R ¹ in the above formula (1) (carbon number of R ² /carbon number of R ¹ ) is preferably 0.8 to 1.2. When the carbon number ratio (carbon number of R ² /carbon number of R ¹ ) is 0.8 to 1.2, the carbon number of R ¹ and the carbon number of R ² become closer to each other, the crystallization of the crystalline resin by the release agent is further promoted, the low-temperature fixing property is improved, and the interaction between the two becomes stronger. Therefore, a stronger layer is formed on the surface of the fixed image, and excellent abrasion resistance is obtained. The carbon number ratio (carbon number of R ² /carbon number of R ¹ ) is more preferably 0.9 to 1.1.

The release agent according to the present invention preferably contains the monomer unit represented by formula (2) in an amount of 50% by mass or more relative to the total amount of monomer units in the release agent. When the amount of the monomer unit represented by formula (2) is 50% by mass or more, the crystallization of the crystalline resin is promoted, the low-temperature fixing property is improved, and the interaction between the two is strengthened, so that a stronger layer is formed on the surface of the fixed image, and excellent abrasion resistance is obtained.
In addition, when the release agent contains two or more types of monomer units represented by formula (2), the content ratio of the monomer units represented by formula (2) represents the total mass ratio of the two or more types of monomer units.

<Other resins>
The binder resin of the toner according to the present invention may contain a resin other than the crystalline resin, if necessary, for the purpose of improving pigment dispersibility.
Examples of resins other than the crystalline resin used in the binder resin of the toner according to the present invention include the following resins: homopolymers of styrene and its substitutes, such as polystyrene, poly-p-chlorostyrene, and polyvinyltoluene; styrene-p-chlorostyrene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene copolymers, styrene-acrylic acid ester copolymers, styrene-methacrylic acid ester copolymers, styrene-α-chloromethyl methacrylate copolymers, styrene-acrylonitrile copolymers, styrene-vinyl methyl ether copolymers, styrene-vinyl ethyl ether copolymers, styrene-vinyl methyl ketone copolymers, and styrene-acrylonitrile-indene copolymers; polyvinyl chloride, phenolic resins, naturally modified phenolic resins, naturally modified maleic acid resins, acrylic resins, methacrylic resins, polyvinyl acetate, silicone resins, polyester resins, polyurethanes, polyamide resins, furan resins, epoxy resins, xylene resins, polyvinyl butyral, terpene resins, coumarone-indene resins, and petroleum-based resins.
Among these, styrene copolymers and polyester resins are preferred, and amorphous resins are also preferred.

<Other release agents>
The toner according to the present invention may contain a release agent other than the release agent according to the present invention, if necessary. Examples of the release agent other than the release agent used in the toner according to the present invention include the following release agents: Hydrocarbon waxes such as microcrystalline wax, paraffin wax, and Fischer-Tropsch wax; oxides of hydrocarbon waxes such as oxidized polyethylene wax or block copolymers thereof; waxes mainly composed of fatty acid esters such as carnauba wax; fatty acid esters partially or completely deoxidized such as deoxidized carnauba wax. In addition, the following may be mentioned. Saturated straight-chain fatty acids such as palmitic acid, stearic acid, and montanic acid; unsaturated fatty acids such as brassidic acid, eleostearic acid, and parinaric acid; saturated alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnaubyl alcohol, ceryl alcohol, and melissyl alcohol; polyhydric alcohols such as sorbitol; esters of fatty acids such as palmitic acid, stearic acid, behenic acid, and montanic acid and alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnaubyl alcohol, ceryl alcohol, and melissyl alcohol; fatty acid amides such as linoleic acid amide, oleic acid amide, and lauric acid amide; methylene bisstearic acid amide, ethylene biscapric acid amide, ethylene bislauric acid amide, hexamethylene bisstearic acid amide, ethylene bisstearic acid amide, ethylene bisstearic acid amide, hexam ... Examples of the suitable release agents include saturated fatty acid bisamides such as stearic acid amide, unsaturated fatty acid amides such as ethylene bisoleic acid amide, hexamethylene bisoleic acid amide, N,N' dioleyl adipic acid amide, and N,N' dioleyl sebacic acid amide, aromatic bisamides such as m-xylene bisstearic acid amide and N,N' distearyl isophthalic acid amide, aliphatic metal salts (generally known as metal soaps) such as calcium stearate, calcium laurate, zinc stearate, and magnesium stearate, waxes obtained by grafting an aliphatic hydrocarbon wax with a vinyl monomer such as styrene or acrylic acid, partial esters of fatty acids and polyhydric alcohols such as behenic acid monoglyceride, and methyl ester compounds having a hydroxyl group obtained by hydrogenating vegetable oils and fats. The content of the other release agents is preferably 40.0 parts by mass or less relative to the amount of the release agent added according to the present invention.

<Coloring Agent>
The toner particles according to the present invention may contain a colorant, if necessary. Examples of the colorant include the following.
Examples of black colorants include carbon black, and a mixture of a yellow colorant, a magenta colorant, and a cyan colorant toned to black. As the colorant, a pigment may be used alone, but it is more preferable to use a dye and a pigment in combination to improve the clarity of the colorant from the viewpoint of the image quality of a full-color image.

Pigments for magenta toner include the following: C.I. C.I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48:2, 48:3, 48:4, 49, 50, 51, 52, 53, 54, 55, 57:1, 58, 60, 63, 64, 68, 81:1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 146, 147, 150, 163, 184, 202, 206, 207, 209, 238, 269, 282; C.I. Pigment Violet 19; C.I. Bat Red 1, 2, 10, 13, 15, 23, 29, 35.

Dyes for magenta toner include the following: C.I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121; C.I. Disperse Red 9; C.I. Solvent Violet 8, 13, 14, 21, 27; C.I. Disperse Violet 1; basic dyes such as C.I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40; C.I. Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28.

Pigments for cyan toner include the following: C.I. Pigment Blue 2, 3, 15:2, 15:3, 15:4, 16, 17; C.I. Vat Blue 6; C.I. Acid Blue 45; copper phthalocyanine pigments with 1 to 5 phthalimidomethyl groups substituted on the phthalocyanine skeleton.

Dyes for cyan toner include C.I. Solvent Blue 70.
Yellow toner pigments include: C.I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 62, 65, 73, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155, 168, 174, 175, 176, 180, 181, 185; C.I. Vat Yellow 1, 3, 20.
Yellow toner dyes include C.I. Solvent Yellow 162.

These colorants can be used alone or in combination, or in the form of a solid solution. The colorant is selected in consideration of hue angle, chroma, brightness, light resistance, OHP transparency, and dispersibility in toner.
The content of the colorant is preferably 0.1 to 30.0 parts by mass based on the total amount of the resin components.

<Charge Control Agent>
The toner particles according to the present invention may contain a charge control agent, if necessary. By blending the charge control agent, the charge characteristics can be stabilized, and the amount of triboelectric charge can be controlled to an optimum level according to the development system.
As the charge control agent, known substances can be used, but particularly preferred are metal compounds of aromatic carboxylic acids, which are colorless, can charge the toner quickly, and can stably maintain a constant charge amount.

Examples of negative charge control agents include the following: metal salicylate compounds, metal naphthoate compounds, and metal dicarboxylate compounds. Polymeric compounds having sulfonic acid or carboxylic acid on the side chain, polymeric compounds having sulfonate salts or sulfonate esters on the side chain, and polymeric compounds having carboxylate salts or carboxylate esters on the side chain. Boron compounds, urea compounds, silicon compounds, and calixarenes.
The charge control agent may be added internally or externally to the toner particles. The content of the charge control agent is preferably 0.2 parts by mass to 10.0 parts by mass, and more preferably 0.5 parts by mass to 10.0 parts by mass, based on 100 parts by mass of the binder resin.

<Inorganic fine particles>
The toner according to the present invention may contain inorganic fine particles, if necessary.
The inorganic fine particles may be added internally to the toner particles, or may be mixed with the toner as an external additive. Examples of the inorganic fine particles include silica fine particles, titanium oxide fine particles, alumina fine particles, or composite oxide fine particles thereof. Among the inorganic fine particles, silica fine particles and titanium oxide fine particles are preferred for improving flowability and uniform charging.
The inorganic fine particles are preferably hydrophobized with a hydrophobizing agent such as a silane compound, silicone oil, or a mixture thereof.
From the viewpoint of improving fluidity, the inorganic fine particles as an external additive preferably have a specific surface area of 50 m ² /g to 400 m ² /g. From the viewpoint of improving durability and stability, the inorganic fine particles as an external additive preferably have a specific surface area of 10 m ² /g to 50 m ² /g. In order to achieve both improved fluidity and durability and stability, inorganic fine particles having a specific surface area in the above range may be used in combination.
The content of the external additive is preferably 0.1 parts by mass to 10.0 parts by mass with respect to 100 parts by mass of the toner particles. The toner particles and the external additive can be mixed using a known mixer such as a Henschel mixer.

<Developer>
The toner according to the present invention can be used as a one-component developer, but is more preferably mixed with a magnetic carrier and used as a two-component developer, in that stable images can be obtained over a long period of time.
As the magnetic carrier, for example, the following known ones can be used: surface-oxidized iron powder or unoxidized iron powder, metal particles such as iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, and rare earth elements, alloy particles thereof, and oxide particles thereof, magnetic materials such as ferrite, magnetic material-dispersed resin carriers (so-called resin carriers) containing a magnetic material and a binder resin that holds the magnetic material in a dispersed state, and the like.
When the toner according to the present invention is mixed with a magnetic carrier to be used as a two-component developer, the mixing ratio of the carrier in this case is preferably 2.0% by mass to 15.0% by mass, more preferably 4.0% by mass to 13.0% by mass, in terms of the toner concentration in the two-component developer. When the ratio is within this range, good results are usually obtained.

<Toner Manufacturing Method>
The toner according to the present invention may be produced by any known method, such as a pulverization method, a suspension polymerization method, a dissolution suspension method, an emulsion aggregation method, or a dispersion polymerization method, without any particular limitation.
The procedure for producing the toner by the pulverization method will be described below.
In the raw material mixing process, materials constituting the toner particles, such as binder resin, wax, colorant, and other components such as a charge control agent as necessary, are weighed out in predetermined amounts, blended, and mixed. Examples of mixing devices include a double con mixer, a V-type mixer, a drum type mixer, a super mixer, a Henschel mixer, a Nauta mixer, and a Mechano Hybrid (manufactured by Nippon Coke & Engineering Co., Ltd.).

Next, the mixed materials are melt-kneaded to disperse the wax in the binder resin. In the melt-kneading process, a batch kneader such as a pressure kneader or a Banbury mixer, or a continuous kneader can be used, and single-screw or twin-screw extruders are the mainstream due to their advantage of continuous production. Examples include a KTK twin-screw extruder (manufactured by Kobe Steel, Ltd.), a TEM twin-screw extruder (manufactured by Toshiba Machine Co., Ltd.), a PCM kneader (manufactured by Ikegai Iron Works), a twin-screw extruder (manufactured by KCK Corporation), a Co-Kneader (manufactured by Buss Co., Ltd.), and Kneadex (manufactured by Nippon Coke and Engineering Co., Ltd.). Furthermore, the resin composition obtained by melt-kneading may be rolled with a twin roll or the like and cooled with water in a cooling process.

The cooled resin composition is then pulverized to the desired particle size in a pulverization process. In the pulverization process, the resin composition is coarsely pulverized using a pulverizer such as a crusher, hammer mill, or feather mill. The resin composition is then further pulverized using a pulverizer such as a Cryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), a Super Rotor (manufactured by Nisshin Engineering Co., Ltd.), a Turbo Mill (manufactured by Turbo Kogyo Co., Ltd.), or an air jet type pulverizer.

Thereafter, if necessary, classification is performed using a classifier or sieve separator as described below.
Elbow Jet (manufactured by Nippon Steel Mining Co., Ltd.), which uses an inertial classification method, Turboplex (manufactured by Hosokawa Micron Corporation), which uses a centrifugal classification method, TSP Separator (manufactured by Hosokawa Micron Corporation), and Faculty (manufactured by Hosokawa Micron Corporation).

Furthermore, if necessary, an external additive is added to the surface of the toner particles. As a method for adding an external additive, a method is mentioned in which the classified toner and various known external additives are mixed in predetermined amounts and stirred and mixed using a mixer as an external adder.
Double con mixer, V-type mixer, drum type mixer, super mixer, Henschel mixer, Nauta mixer, Mechano Hybrid (manufactured by Nippon Coke and Engineering Co., Ltd.), Nobilta (manufactured by Hosokawa Micron Corporation), etc.
The methods for measuring various physical properties of the toner particles and raw materials will be described below.

<Method of separating each material from toner>
By utilizing the difference in solubility of each material contained in the toner in a solvent, each material can be separated from the toner.
First separation: Toner (crystalline resin, wax, colorant, inorganic fine particles, etc.) is dissolved in MEK (methyl ethyl ketone) at 100° C., and the soluble matter (crystalline resin, wax) and insoluble matter (colorant, inorganic fine particles, etc.) are separated.
Second separation: The soluble matter (crystalline resin, wax) obtained in the first separation is dissolved in chloroform at 23° C., and the soluble matter (crystalline resin) and the insoluble matter (wax) are separated.

<Method for measuring the proportion of monomer units derived from various polymerizable monomers in a crystalline resin>
The content of monomer units derived from various polymerizable monomers in the crystalline resin is measured by ¹ H-NMR under the following conditions.
Measuring device: FT NMR device JNM-EX400 (manufactured by JEOL Ltd.)
Measurement frequency: 400MHz
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 chamber at 40° C. to prepare a measurement sample.

From the obtained ^1H -NMR chart, for example, in the case of a polymer, a peak independent of peaks attributable to components of monomer units derived from the first polymerizable monomer is selected, and an integral value _S1 of the selected peak is calculated.

Similarly, from the peaks attributable to the components of the monomer unit derived from the second polymerizable monomer, a peak independent of the peaks attributable to the components of the monomer units derived from the other monomer units is selected, and an integral value _S2 of this selected peak is calculated.
Furthermore, when a third polymerizable monomer is used, a peak independent of the peaks attributable to the constituent elements of the monomer unit derived from the third polymerizable monomer is selected from the peaks attributable to the constituent elements of the monomer unit derived from the other monomer units, and the integral value _S3 of the selected peak is calculated.

The content ratio of the monomer unit derived from the first polymerizable monomer is determined using the above integral values _S1 , _S2 , and _S3 as follows: Here, _n1 , _{n2, and n3} are the numbers of hydrogen atoms in the constituent elements to which the peak of interest for each site belongs.
Content (mol %) of monomer unit derived from first polymerizable monomer=
{(S ₁ /n ₁ )/((S ₁ /n ₁ )+(S ₂ /n ₂ )+(S ₃ /n ₃ ))}×100
Similarly, the content ratios of the monomer units derived from the second polymerizable monomer and the third polymerizable monomer are determined as follows.
Content (mol %) of monomer unit derived from second polymerizable monomer=
{(S ₂ /n ₂ )/((S ₁ /n ₁ )+(S ₂ /n ₂ )+(S ₃ /n ₃ ))}×100
Content (mol %) of monomer unit derived from third polymerizable monomer=
{(S ₃ /n ₃ )/((S ₁ /n ₁ )+(S ₂ /n ₂ )+(S ₃ /n ₃ ))}×100
In addition, when a polymerizable monomer containing no hydrogen atoms in components other than vinyl groups is used in polymer A, the measurement nucleus is set to ¹³ C using ¹³ C-NMR, and the measurement is performed in single pulse mode, and the calculation is performed in the same manner using ¹ H-NMR.

<SP value calculation method>
The SP value of the monomer unit derived from various polymerizable monomers of the crystalline resin is determined as follows according to the calculation method proposed by Fedors.
For each atom or atomic group in the molecular structure, the evaporation energy (Δei) (cal/mol) and molar volume (Δvi) (cm ³ /mol) are obtained 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 .

<Measurement of weight average molecular weight of crystalline resin by GPC>
The molecular weight (Mw) of the THF-soluble portion of the crystalline resin is measured by gel permeation chromatography (GPC) as follows.
First, the toner 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 approximately 0.8% by mass. This sample solution is used to perform measurements 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: 1.0mL/min
Oven temperature: 40.0°C
Sample injection volume: 0.10 mL
In calculating the molecular weight of the 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.

<Measurement of weight average molecular weight of release agent by GPC>
The weight average molecular weight of the release agent is measured by gel permeation chromatography (GPC) as follows: Special grade 2,6-di-t-butyl-4-methylphenol (BHT) is added to o-dichlorobenzene for gel chromatography so that the concentration becomes 0.10 mass/volume %, and dissolved at room temperature.
The release agent and the o-dichlorobenzene to which the BHT has been added are placed in a sample bottle, which is then heated on a hot plate set at 150°C to dissolve the release agent. Once the release agent has dissolved, it is placed in a preheated filter unit and placed in the main body. The sample that has passed through the filter unit is used as the GPC sample. The concentration of the sample solution is adjusted to 0.15% by mass. This sample solution is used to perform measurements under the following conditions.

・Equipment: HLC-8121GPC/HT (manufactured by Tosoh Corporation)
・Detector: RI for high temperature
Column: TSKgel GMHHR-H HT 2-unit (Tosoh Corporation)
・Temperature: 135.0℃
Solvent: o-dichlorobenzene for gel chromatography (containing 0.10 mass/volume % BHT)
・Flow rate: 1.0mL/min
・Injection volume: 0.4mL
In calculating the molecular weight of the release agent, a standard polystyrene resin (for example, trade names "TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, A molecular weight calibration curve prepared using "A-5000, A-2500, A-1000, A-500" (manufactured by Tosoh Corporation) is used.

<Method for measuring the peak top temperature of the endothermic peak measured by differential scanning calorimetry (DSC) of a crystalline resin>
<Method for measuring the endothermic peak top temperature of a release agent measured by differential scanning calorimetry (DSC)>
The peak top temperature of the endothermic peak of the crystalline resin measured by differential scanning calorimetry (DSC) and the peak top temperature of the endothermic peak of the release agent measured by differential scanning calorimetry (DSC) are measured in accordance with ASTM D3418-82. A differential scanning calorimeter "Q2000" (manufactured by TA Instruments) is used as the measuring device.
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 amount of heat.

Specifically, about 3 mg of a sample is precisely weighed and placed in an aluminum pan, and measurement is performed under the following conditions using an empty aluminum pan as a reference.
Heating rate: 10° C./min
Measurement start temperature: 30℃
Measurement end temperature: 180°C
Measurements are performed at a temperature rise rate of 10°C/min in the measurement range of 30 to 180°C. The temperature is raised to 180°C once and held for 10 minutes, then lowered to 30°C, and then raised again. During this second temperature rise process, the peak top temperatures of the crystalline resin and the release agent are calculated from the temperature-endothermic curve in the temperature range of 30°C to 80°C.

The basic configuration and features of the present invention have been described above. The present invention will now be described in detail with reference to examples. However, the present invention is in no way limited to these. Note that parts and percentages are by weight unless otherwise specified.

<Production Example of Crystalline Resin 1>
Solvent: toluene 100.0 parts Monomer composition 100.0 parts (the monomer composition is a mixture of behenyl acrylate, acrylonitrile, and styrene in the ratio shown below)
Behenyl acrylate (first polymerizable monomer): 50.00 parts Acrylonitrile (second polymerizable monomer): 35.00 parts Styrene (third polymerizable monomer): 15.00 parts Polymerization initiator t-butyl peroxypivalate (Perbutyl PV, manufactured by NOF Corp.): 0.5 parts

The above materials were put into a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, and a nitrogen inlet tube under a nitrogen atmosphere. The reaction vessel was heated to 70°C while stirring at 200 rpm to carry out a polymerization reaction for 12 hours, obtaining a solution in which the polymer of the monomer composition was dissolved in toluene. The solution was then cooled to 25°C, and the solution was poured into 1000.0 parts of methanol while stirring to precipitate the methanol insoluble matter. The resulting methanol insoluble matter was filtered off, washed with methanol, and dried under reduced pressure at 40°C for 24 hours to obtain crystalline resin 1. The weight average molecular weight of crystalline resin 1 was 67,100, and the peak top temperature (endothermic peak temperature) of the temperature-endothermic curve was 62°C.

<Production Examples of Crystalline Resin 2 to Crystalline Resin 9>
Crystalline resins 2 to 9 were obtained by carrying out the reaction in the same manner as in the production example of crystalline resin 1, except that the polymerizable monomers and the parts thereof were changed as shown in Table 1.

The abbreviations in Table 1 are as follows.
BEA: Behenyl acrylate CH ₂ ═CH—C(═O)—O(CH ₂ ) ₂₁ CH ₃
MYA: Myrisil acrylate CH ₂ ═CH—C(═O)—O(CH ₂ ) ₂₉ CH ₃
OA: Octacosaacrylate CH ₂ ═CH—C(═O)—O(CH ₂ ) ₂₇ CH ₃
SA: Stearyl acrylate CH ₂ ═CH-C(═O)-O(CH ₂ ) ₁₇ CH ₃
HA: Hexadecyl acrylate CH ₂ ═CH—C(═O)—O(CH ₂ ) ₁₅ CH ₃
AN: acrylonitrile CH ₂ ═CH—CN
MN: methacrylonitrile CH ₂ ═C(—CH ₃ )—CN
VA: vinyl acetate CH ₂ ═CH—O—C(═O)—CH _3
St : styrene _CH2 =CH- _C6H5

<Production Example of Release Agent 1>
Solvent: toluene 100.0 parts, 1-docosene 85.0 parts, 1-butene 15.0 parts The above materials and the following materials were added to a heated and dried autoclave under a hydrogen atmosphere, and polymerization was carried out at 160° C. for 180 minutes.
Triisobutylaluminum 0.5mmol
(1,2'-Dimethylsilylene)(2,1'-dimethylsilylene)bis(3-trimethylsilylmethylindenyl)zirconium dichloride 2μmol
Dimethylanilinium tetrakispentafluorophenylborate 8 μmol
After the polymerization reaction was completed, the precipitated reaction product was separated at 25° C., washed with acetone, and then dried under heating and reduced pressure to obtain a release agent 1. The weight average molecular weight of the release agent 1 was 5,000, and the peak top temperature of the temperature-endothermic curve was 58° C.

<Production Examples of Release Agents 2 to 18>
Release agents 2 to 18 were obtained by carrying out the reaction in the same manner as in the production example of release agent 1, except that the polymerizable monomers and the parts thereof were changed as shown in Table 2.

<Production Example of Toner 1>
Crystalline resin 1 100.0 parts by mass Release agent 1 10.0 parts by mass C.I. Pigment Blue 15:3 9.0 parts by mass The raw materials shown in the recipe were mixed using a Henschel mixer (FM75J type, manufactured by Mitsui Miike Chemical Engineering Co., Ltd.) at a rotation speed of 20 s ^-1 for a rotation time of 5 min, and then kneaded using a twin-screw kneader (PCM-30 type, manufactured by Ikegai Co., Ltd.) set at a temperature of 130°C and a barrel rotation speed of 200 rpm. The kneaded product obtained was cooled and coarsely crushed to 1 mm or less using a hammer mill to obtain a coarsely crushed product. The coarsely crushed product obtained was finely crushed using a mechanical crusher (T-250, manufactured by Turbo Kogyo Co., Ltd.). Furthermore, classification was performed using a rotary classifier (200TSP, manufactured by Hosokawa Micron Corporation) to obtain toner particles 1.
100.0 parts by mass of the obtained toner particles 1' were mixed with 2.0 parts of hydrophobic silica (BET: 200 ^m2 /g) in a Henschel mixer (FM75J type, manufactured by Mitsui Miike Chemical Engineering Co., Ltd.) at a rotation speed of 30 s ^-1 for a rotation time of 5 min, and passed through an ultrasonic vibration sieve with a mesh size of 54 μm to obtain toner 1.

<Production Examples of Toners 2 to 30>
Toners 2 to 30 were obtained in the same manner as in the production example of toner 1, except that the types and amounts of crystalline resin 1 and release agent 1 were changed to those shown in Table 3.

<Production Example of Magnetic Core Particles>
(Step 1: Weighing and mixing step)
The ferrite raw materials were weighed so as to _obtain the above composition ratio. Then, the materials were pulverized and mixed for 5 hours in a dry vibration mill _using stainless steel _beads with _a diameter _of 1/8 inch.

Step 2 (pre-firing step):
The obtained pulverized material was made into pellets of about 1 mm square using a roller compactor. The pellets were passed through a vibrating sieve with 3 mm openings to remove coarse powder, and then passed through a vibrating sieve with 0.5 mm openings to remove fine powder. The pellets were then fired in a burner-type firing furnace at 1,000° C. for 4 hours in a nitrogen atmosphere (oxygen concentration 0.01% by volume) to produce calcined ferrite. The composition of the resulting calcined ferrite was as follows:
(MnO) _a (MgO)b(SrO)c( _Fe2O3 )d
In the above formula, a = 0.257, b = 0.117, c = 0.007, d = 0.393

(Step 3: Crushing step)
After crushing to about 0.3 mm with a crusher, 30 parts by mass of water was added to 100 parts by mass of the calcined ferrite and crushed in a wet ball mill using zirconia beads with a diameter of 1/8 inch for 1 hour. The slurry was crushed for 4 hours in a wet ball mill using alumina beads with a diameter of 1/16 inch to obtain a ferrite slurry (finely crushed calcined ferrite).
(Step 4: Granulation step)
To the ferrite slurry, 1.0 part by mass of ammonium polycarboxylate as a dispersant and 2.0 parts by mass of polyvinyl alcohol as a binder were added per 100 parts by mass of the calcined ferrite. The mixture was then granulated into spherical particles using a spray dryer (manufacturer: Okawara Kakoki Co., Ltd.). After adjusting the particle size of the resulting particles, the mixture was heated in a rotary kiln at a temperature of 650° C. for 2 hours to remove the organic components of the dispersant and binder.

(Step 5: Firing step)
In order to control the firing atmosphere, the material was heated from room temperature to 1,300° C. in a nitrogen atmosphere (oxygen concentration 1.00% by volume) in an electric furnace over a period of 2 hours, and then fired at a temperature of 1,150° C. for 4 hours. The temperature was then lowered to 60° C. over a period of 4 hours, and the material was returned from the nitrogen atmosphere to the air and taken out at a temperature of 40° C. or less.
(Step 6: Selection step)
After the aggregated particles were crushed, low magnetic particles were removed by magnetic separation, and coarse particles were removed by sieving through a sieve with 250 μm openings, to obtain magnetic core particles 1 having a volume distribution-based median diameter of 37.0 μm.

[Preparation of coating resin]
Cyclohexyl methacrylate monomer 26.8% by mass
Methyl methacrylate monomer 0.2% by mass
Methyl methacrylate macromonomer 8.4% by mass
(A macromonomer having a weight average molecular weight of 5,000 and having a methacryloyl group at one end)
Toluene 31.3% by mass
Methyl ethyl ketone 31.3% by mass
Azobisisobutyronitrile 2.0% by mass

Of the above materials, cyclohexyl methacrylate, methyl methacrylate, methyl methacrylate macromonomer, toluene, and methyl ethyl ketone were placed in a four-necked separable flask equipped with a reflux condenser, a thermometer, a nitrogen inlet tube, and a stirrer. Nitrogen gas was then introduced to replace the inside of the system with nitrogen gas. The mixture was then heated to a temperature of 80°C, and azobisisobutyronitrile was added and refluxed for 5 hours to polymerize. Hexane was injected into the resulting reaction product to precipitate a copolymer, and the precipitate was filtered and dried under reduced pressure to obtain coating resin 1. 30 parts by mass of the resulting coating resin 1 was dissolved in 40 parts by mass of toluene and 30 parts by mass of methyl ethyl ketone to obtain polymer solution 1 (solid content 30% by mass).

[Preparation of coating resin solution]
・Polymer solution 1 (resin solid content concentration 30%) 33.3% by mass
Toluene 66.4% by mass
Carbon black 0.3% by mass
(Primary particle size 25 nm, nitrogen adsorption specific surface area 94 m ² /g, DBP oil absorption 75 mL/100 g)
The above materials were dispersed for 1 hour using zirconia beads having a diameter of 0.5 mm in a paint shaker. The resulting dispersion was filtered through a 5.0 μm membrane filter to obtain a coating resin solution 1.

[Magnetic Carrier Production Example]
(Resin coating process)
The coating resin solution 1 was added to a vacuum degassing kneader maintained at room temperature so that the resin component was 2.5 parts by mass per 100 parts by mass of the ferrite particles 1. After addition, the mixture was stirred at a rotation speed of 30 rpm for 15 minutes, and after a certain amount of the solvent (80% by mass) had evaporated, the mixture was heated to 80°C while mixing under reduced pressure, and the toluene was distilled off over 2 hours, after which the mixture was cooled. The magnetic carrier obtained was separated into low magnetic products by magnetic separation, passed through a sieve with an opening of 70 μm, and then classified by a wind classifier to obtain a magnetic carrier 1 having a median diameter based on volume distribution of 38.2 μm.

<Production Examples of Two-Component Developers 1 to 30>
The toners 1 to 39 and magnetic carrier 1 (number average particle size 35 μm) were mixed in a V-type mixer (V-10 type: Tokuju Manufacturing Co., Ltd.) for 0.5 s ⁻¹ and 5 minutes so that the toner concentration became 9% by mass, to obtain two-component developers 1 to 30.

<Toner Evaluation>
A modified Canon Inc. full-color copier ImagePRESS C800 was used as the image forming apparatus, and two-component developer 1 was placed in the developing device of the station of the cyan process cartridge. The apparatus was modified so that the fixing temperature, process speed, developer carrier DC voltage V _DC , electrostatic latent image carrier charging voltage V _D , and laser power could be freely set. The image output evaluation was performed by outputting an image with a desired image ratio, and adjusting V _DC , V _D , and laser power so that the amount of toner on the image on the paper was desired, and then performing the evaluation described below.
FFh is a value that expresses 256 gradations in hexadecimal, with 00h being the first gradation (white background) of the 256 gradations, and FFh being the 256th gradation (solid portion) of the 256 gradations.
The evaluation was performed based on the following evaluation methods, and the results are shown in Table 4.

[Low temperature fixability]
Paper: Mondi color copy paper (300.0 g/ ^m2 )
(Sold by Mondi)
Toner loading on paper: 0.90 mg/cm ² (FFh image)

(Adjusted by DC voltage V _DC of developer carrier, charging voltage V _D of electrostatic latent image carrier, and laser power)
Evaluation image: A 2 cm x 5 cm image is placed in the center of the A4 paper. Test environment: Low temperature and low humidity environment: temperature 15°C / relative humidity 10% (hereinafter referred to as "L/L")
Fixing temperature: 170°C
Process speed: 348 mm/sec

The above evaluation image was output, and the low-temperature fixing property was evaluated. The value of the image density reduction rate was used as an evaluation index for the low-temperature fixing property.
The image density reduction rate is measured by first measuring the image density at the center using an X-Rite color reflection densitometer (500 series: manufactured by X-Rite Corporation). Next, a load of 4.9 kPa (50 g/cm ² ) is applied to the part where the image density was measured, and the fixed image is rubbed (five times back and forth) with Silbon paper, and the image density is measured again.
The rate of decrease in image density before and after rubbing was calculated using the following formula. The rate of decrease in image density obtained was evaluated according to the following evaluation criteria. If the evaluation was A to H, it was determined that the effects of the present invention were obtained.
Image density decrease rate=(image density before friction−image density after friction)/image density before friction×100

(Evaluation Criteria)
A: Image density reduction rate is less than 1.0% B: Image density reduction rate is 1.0% or more and less than 2.0% C: Image density reduction rate is 2.0% or more and less than 3.0% D: Image density reduction rate is 3.0% or more and less than 4.0% E: Image density reduction rate is 4.0% or more and less than 5.0% F: Image density reduction rate is 5.0% or more and less than 6.0% G: Image density reduction rate is 6.0% or more and less than 7.0% H: Image density reduction rate is 7.0% or more and less than 8.0% I: Image density reduction rate is 8.0% or more and less than 9.0% J: Image density reduction rate is 9.0% or more and less than 10.0% K: Image density reduction rate is 10.0% or more

[Abrasion resistance]
Paper: OK Topcoat Matte N157 (157.0 g/m ² )
(Sold by Oji Paper Co., Ltd., uses calcium carbonate as coating material)
Toner loading on paper: 0.05 mg/cm ² (2Fh image)
(Adjusted by DC voltage V _DC of developer carrier, charging voltage V _D of electrostatic latent image carrier, and laser power)
Evaluation image: A 3 cm x 15 cm image is placed in the center of the A4 paper Fixing test environment: Normal temperature and humidity environment (temperature 23°C / relative humidity 50% (hereinafter N/N))
Fixing temperature: 180°C
Process speed: 348 mm/sec

The above evaluation image was output and the scratch resistance was evaluated. The difference in reflectance was used as an evaluation index for the scratch resistance.
First, the image portion of the evaluation image is rubbed (10 times back and forth) with a new evaluation paper under a load of 1.0 kgf using a Gakushin type rub fastness tester (AB-301: manufactured by Tester Sangyo Co., Ltd.) After that, the reflectance of the rubbed portion of the new evaluation paper and the reflectance of the non-rubbed portion are measured using a reflectometer (REFLECTOMETER MODEL TC-6DS: manufactured by Tokyo Denshoku Co., Ltd.).
The difference in reflectance before and after rubbing was calculated using the following formula. The resulting difference in reflectance was evaluated according to the following evaluation criteria. If the evaluation was A to L, it was determined that the effects of the present invention were obtained.
Difference in reflectance = reflectance of non-friction area - reflectance of friction area

(Evaluation Criteria)
A: Less than 1.0% B: 1.0% or more, less than 2.0% C: 2.0% or more, less than 3.0% D: 3.0% or more, less than 4.0% E: 4.0% or more, less than 5.0% F: 5.0% or more, less than 6.0% G: 6.0% or more, less than 7.0% H: 7.0% or more, less than 8.0% I: 8.0% or more, less than 9.0% J: 9.0% or more, less than 10.0% K: 10.0% or more, less than 11.0% L: 11.0% or more, less than 12.0% M: 12.0% or more, less than 13.0% N: 13.0% or more, less than 14.0% O: 14.0% or more

Two-component developers 2 to 30 were also evaluated in the same manner as two-component developer 1. The results are shown in Table 4.

[Comparative Example 1]
The toner 28 used in Comparative Example 1 is a toner in which the number of carbon atoms in the alkyl group of the release agent is large and the maximum endothermic peak temperature is high at 92°C.

[Comparative Example 2]
Toner 29 used in Comparative Example 2 is a toner in which the proportion of the first monomer unit in the crystalline resin is as low as 28% by mass.

[Comparative Example 3]
The toner 30 used in Comparative Example 3 is a toner in which the first monomer unit in the crystalline resin is hexadecyl acrylate (R ¹ has 16 carbon atoms).

Claims (7)

A toner having toner particles containing a binder resin and a release agent,
The binder resin contains a crystalline resin,
The crystalline resin has a first monomer unit represented by the following formula (1):
a ratio of the first monomer unit in the crystalline resin is 30.0% by mass to 100.0% by mass based on the total mass of all monomer units in the crystalline resin;

[In formula (1), R _Z1 represents a hydrogen atom or a methyl group, and R ¹ represents an alkyl group having 18 to 36 carbon atoms.]
The release agent contains an α-olefin polymer having a unit represented by the following formula (2):

[In formula (2), R ² represents an alkyl group having 18 to 36 carbon atoms.]
The toner is characterized in that the maximum endothermic peak temperature of the α-olefin polymer is 40° C. to 90° C. as measured by a differential scanning calorimeter (DSC). The toner according to claim 1, wherein the weight average molecular weight (Mw) of the release agent is 1,000 to 10,000. The toner according to claim 1 or 2, wherein the content of the release agent contained in the toner particles is 1.0 parts by mass to 20.0 parts by mass per 100 parts by mass of the crystalline resin. 4. The toner according to claim 1, wherein the ratio of the number of carbon atoms in said formula (2) to the number of carbon atoms in R ¹ in said formula (1) is from 0.8 to 1.2. The toner according to any one of claims 1 to 4, wherein the ratio of the monomer unit represented by formula (2) in the release agent is 50% by mass or more based on the total monomer units in the release agent. The toner according to any one of claims 1 to 5, wherein the first monomer unit is behenyl acrylate. The crystalline resin is
The copolymer has a second monomer unit represented by the following formula (3) or (4) which is different from the first monomer unit,
7. The toner according to claim 1, wherein when the SP value of the second monomer unit is taken as SP2 (J/cm ³ ) ^0.5 , the following relational expression is satisfied: SP2<0.5>=SP2<0.5>/(J/cm 3 )<0.5>.
21.00 (J/cm ³ ) ^0.5 ≦SP2

(In the formula, X represents a single bond or an alkylene group having 1 to 6 carbon atoms,
^R3 is
A nitrile group (—C≡N),
an amide group (-C(=O)NHR ¹⁰ (R ¹⁰ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms);
Hydroxy groups,
-COOR ³¹ (R ³¹ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a hydroxyalkyl group having 1 to 6 carbon atoms),
a urea group (-NH-C(=O)-N( ^R33 ) ₂ (each ^R33 independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms);
-COO( _CH2 ) _2NHCOOR34 ( ^{wherein R34} represents an alkyl group having 1 to 4 carbon atoms), or -COO( _CH2 ) ₂ -NH-C(=O)-N( ^R35 ) ₂ (wherein ^R35 each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms).
represents
^R4 represents a hydrogen atom or a methyl group.

(In the formula, R ⁵ represents an alkyl group having 1 to 4 carbon atoms,
^R6 represents a hydrogen atom or a methyl group.