JP2019070736A - Two-component developer - Google Patents

Abstract

To provide a two-component developer that can output a high-quality image for a long period even when the environment changes.SOLUTION: A two-component developer contains a toner containing an amorphous resin, wax, and wax dispersant, and a magnetic carrier having a resin coating layer on its surface. The wax dispersant has a polymer in which a styrene-acrylic polymer is graft polymerized with polyolefin; the styrene-acrylic polymer has a structure derived from a saturated alicyclic compound; the magnetic carrier has a surface roughness Ra of 0.220 μm or less; the resin coating layer contains a coating resin A and a coating resin B; the coating resin A is a polymer of a monomer containing a (meth)acrylate monomer having an alicyclic hydrocarbon group; the coating resin B is a polymer of a monomer containing a (meth)acrylate monomer having a polar group; and the content of the coating resins A and B in the resin coating layer falls within a specific range.SELECTED DRAWING: None

Description

  The present invention relates to a two-component developer used in an electrophotographic system, an electrostatic recording system, an electrostatic printing system, and a toner jet system.

In recent years, with technological advances in the field of electrophotography, demands for higher speed, longer life, higher definition, stabilized image quality, energy saving, and the like have become increasingly strict. That is, it is important for the two-component developer that the charge amount of the toner is unlikely to change with long-term use, and the charge amount does not change easily even with environmental changes (the environmental difference is small). In order to achieve these, an approach from both carrier and toner is indispensable.
As a toner for a two-component developer, a toner using a crystalline polyester resin as a plasticizer for an amorphous polyester resin has been proposed in order to achieve low-temperature fixing (Patent Document 1).
By using the crystalline polyester resin, the plasticized non-crystalline polyester resin is reduced in viscosity, and a certain effect on low temperature fixability is obtained. However, under the high temperature and high humidity environment, there is a problem that the chargeability is lowered because the resistance of the crystalline polyester resin is small. On the other hand, there has been proposed a toner which suppresses the exposure of crystalline polyester to the surface of toner particles and achieves both the fixing property and the charge maintaining property (Patent Document 2).

On the other hand, as a magnetic carrier for a two-component developer, lightweight composite particles having a specific gravity of about 2.0 or more and about 5.0 or less, which are difficult to break the toner even by speeding up and continuous image output, are used. (Patent Document 3).
In order to obtain lightweight composite particles, it is general to form a magnetic carrier core with a magnetic component and a resin component. However, as a problem that may occur by using a resin component for the magnetic carrier core, there are fluctuations in image density and tint with respect to environmental fluctuations from low humidity environment to high humidity environment. It is considered that this is due to the water adsorptivity of the resin component.
As a technique for suppressing the moisture adsorption amount of magnetic carrier particles, Patent Documents 4 to 6 describe a technique in which the moisture adsorption amount of magnetic carrier particles is specified.

Japanese Patent Application Laid-Open No. 2004-046095 JP, 2016-45358, A Unexamined-Japanese-Patent No. 2006-337579 Patent Document 1: Japanese Patent Application Publication No. 2001-075315 JP-A-9-127736 JP, 2009-139707, A

While such development progresses, in recent years, the initial cost reduction of the apparatus is also required, and as a technology therefor, development of a two-component type developer having developability equal to that of the AC development system is also required. There is. Along with this, a two-component developer with further improved developability is required, and in particular, goodness of carrier separation of toner against environmental fluctuation from high humidity environment to low humidity environment becomes important.
From the above, there is an urgent need to develop a two-component developer in which the charge amount does not change easily and the toner and the carrier are easily separated non-electrostatically against environmental fluctuations and long-term use. .
An object of the present invention is to provide a two-component developer which solves the problems as described above. Specifically, the present invention is to provide a two-component developer which can output a high quality image over a long period even if the environment changes.

The present invention is a two-component developer comprising a toner and a magnetic carrier,
The toner is a toner having toner particles comprising an amorphous resin, a wax and a wax dispersant,
The wax dispersant has a polymer in which a styrene acrylic polymer is graft-polymerized to a polyolefin,
The styrene acrylic polymer has a structure derived from a saturated alicyclic compound,
The magnetic carrier has a magnetic carrier core and a resin coating layer on the surface of the magnetic carrier core,
The surface roughness Ra of the magnetic carrier is 0.220 μm or less,
The resin coating layer contains a coating resin A and a coating resin B,
The coating resin A is a polymer of a monomer containing a (meth) acrylic acid ester monomer having an alicyclic hydrocarbon group,
The coating resin B is a polymer of a monomer containing a (meth) acrylic monomer having a polar group,
The content of the coating resin A in the resin coating layer is 10% by mass or more and 90% by mass or less based on the mass of the resin component in the resin coating layer,
A two-component developer characterized in that the content of the coating resin B in the resin coating layer is 10% by mass or more and 90% by mass or less based on the mass of the resin component in the resin coating layer. About.

  According to the present invention, it is possible to provide a two-component developer capable of outputting a high quality image over a long period even if the environment changes.

Schematic of surface treatment equipment Example of peak area for molecular weight distribution measurement Example of peak area for molecular weight distribution measurement

In the present invention, the descriptions of “more than or equal to or less than xxx” and “o to xxx” indicating numerical ranges mean numerical ranges including the lower limit and the upper limit which are end points unless otherwise noted.
The two-component developer of the present invention is a two-component developer containing a toner and a magnetic carrier,
The toner is a toner having toner particles comprising an amorphous resin, a wax and a wax dispersant,
The wax dispersant has a polymer in which a styrene acrylic polymer is graft-polymerized to a polyolefin,
The styrene acrylic polymer has a structure derived from a saturated alicyclic compound,
The magnetic carrier has a magnetic carrier core and a resin coating layer on the surface of the magnetic carrier core,
The surface roughness Ra of the magnetic carrier is 0.220 μm or less,
The resin coating layer contains a coating resin A and a coating resin B,
The coating resin A is a polymer of a monomer containing a (meth) acrylic acid ester monomer having an alicyclic hydrocarbon group,
The coating resin B is a polymer of a monomer containing a (meth) acrylic monomer having a polar group,
The content of the coating resin A in the resin coating layer is 10% by mass or more and 90% by mass or less based on the mass of the resin component in the resin coating layer,
The content of the coating resin B in the resin coating layer is 10% by mass or more and 90% by mass or less based on the mass of the resin component in the resin coating layer.

As described above, good toner separation is required for environmental fluctuations from a high humidity environment to a low humidity environment. Therefore, the present inventors focused on the non-electrostatic adhesion between toner and magnetic carrier. The idea is to make it easy to separate the toner and the carrier by an approach that does not depend on chargeability. The adhesion of the two-component developer placed in a high humidity environment is increased by the adsorption of water on the surface of the toner and the magnetic carrier. Therefore, it is necessary to control the surface state of the toner and the magnetic carrier.
As a result of intensive studies by the present inventors, when toner particles contain a specific wax dispersant, the amount of adsorbed water is suppressed even when the toner is left under high temperature and high humidity, and the adhesion is suppressed. I understand.
Further, the magnetic carrier to be combined in the present invention is required to have a surface roughness in a certain range and to have a stable surface condition of the carrier before and after durable use and against environmental fluctuation. If the surface is too rough, toner will be trapped there and non-electrostatic adhesion will increase. Resin A needs resin B to satisfy environmental fluctuation and durability in order to satisfy the contamination resistance and durability of the film for durable use, and by using a resin obtained by blending them, the respective effects are sufficiently satisfied. Can be obtained.
The present inventors have found that by combining such toner and magnetic carrier, the effects of the toner and the magnetic carrier can be sufficiently obtained, and the present invention has been achieved.

The wax dispersant has a graft polymer having a polyolefin as a main chain, and thus has high affinity with the wax which is a component of the toner, and in the case of a pulverized toner, the wax forms a pulverized interface. Furthermore, since the graft polymer has a structure derived from a highly hydrophobic saturated alicyclic compound, a toner layer is inevitably formed with a highly hydrophobic surface layer. It is estimated that the amount of adsorbed water is thereby suppressed.
Furthermore, it is preferable that the toner particles of the present invention be surface-treated with hot air using, for example, the surface treatment apparatus shown in FIG. Since the toner particles are treated with hot air in a hydrophobic field in the air by the surface treatment apparatus shown in FIG. 1, the wax constituting the toner particles is transferred to the vicinity of the surface of the toner particles and the wax dispersant is also It moves to the vicinity of the surface of the toner particle. Therefore, the hydrophobicity of the surface of the toner particles is increased, and the amount of adsorbed water in a high temperature and high humidity environment is reduced.

The surface roughness Ra of the magnetic carrier is 0.220 μm or less. When the surface roughness Ra exceeds 0.220 μm, not only the particle strength decreases and the durability of the magnetic carrier decreases, but also the toner easily adheres to the depressions of the magnetic carrier, so that white spots easily occur. . Ra is preferably 0.210 μm or less.
The lower limit is not particularly limited, but is preferably 0.160 μm or more, and more preferably 0.170 μm or more. The surface roughness Ra of the magnetic carrier can be controlled by the baking temperature of the magnetic carrier core, the type and amount of the coating resin, and the like.

The (meth) acrylic acid ester monomer having an alicyclic hydrocarbon group used for the synthesis of the coating resin A makes the surface (coating surface) of the resin coating layer covering the surface of the magnetic carrier core smooth. As a result, the adhesion of toner-derived components, such as toner and external additives for imparting fluidity to toner, is suppressed, and the reduction of the charge imparting ability to toner is suppressed. In the absence of the (meth) acrylic acid ester monomer having an alicyclic hydrocarbon group, image defects due to the decrease in the charge imparting ability to the toner are likely to occur during long-term use, particularly in a high temperature and high humidity environment. In addition, since the smoothness of the carrier surface is reduced, the adhesion to the toner is increased, and white spots are easily generated.

The resin coating layer of the magnetic carrier is preferably in a state in which the coating resin A and the coating resin B are mixed.
The content of the coating resin A in the resin coating layer is 10% by mass or more and 90% by mass or less based on the mass of the resin component of the resin coating layer. In addition, the content of the coating resin B in the resin coating layer is 10% by mass or more and 90% by mass or less based on the mass of the resin component of the resin coating layer.
When the content of the coating resin A is less than 10% by mass, or the content of the coating resin B is less than 10% by mass, the surface (coating surface) of the resin coating layer is unlikely to be smooth, In addition, the resin coating layer and the magnetic carrier core do not easily adhere to each other. The content of the coating resin A is preferably 30% by mass to 70% by mass based on the mass of the resin component of the resin coating layer, and the content of the coating resin B is the content of the resin component of the resin coating layer. Preferably it is 30 to 70 mass% on the basis of mass.

  The acid value of the resin component of the resin coating layer is preferably 1.0 mg KOH / g or more and 10.0 mg KOH / g or less. More preferably, it is 1.0 mg KOH / g or more and 5.0 mg KOH / g or less, and still more preferably 2.0 mg KOH / g or more and 5.0 mg KOH / g or less. The resin component of the resin coating layer also includes a coating resin A and a coating resin B. When the acid value of the resin component of the resin coating layer is in the above range, the adhesion between the resin coating layer and the magnetic carrier core, the strength (coating film strength) of the resin coating layer is improved, and the magnetic carrier surface is stabilized.

  When the acid value of the resin component of the resin coating layer is 1.0 mg KOH / g or more, the adhesion between the resin coating layer and the magnetic carrier core is improved. Further, the charge imparting ability to the toner is stabilized, and even if the environment changes, the amount of charge given to the toner hardly changes. On the other hand, when the acid value of the resin component of the resin coating layer is 10.0 mg KOH / g or less, the resin coating layer hardly absorbs moisture, and the charge imparting ability to the toner is stable under long-term use, particularly under high temperature and high humidity environment. Image density etc. is stabilized. Further, the adhesion between the toner and the magnetic carrier is also reduced, and white spots can be prevented.

The minimum value of the storage elastic modulus (G ′) in the range of 70 ° C. to 100 ° C. of the resin component of the resin coating layer is 7.0 × from the viewpoint of the stability of the surface (coating surface) of the resin coating layer. It is preferable that it is 10 ⁷ Pa or more and 1.0 × 10 ⁹ Pa or less. More preferably, it is 9.0 × 10 ⁷ Pa or more and 8.0 × 10 ⁸ Pa or less.
In addition, the minimum value of loss elastic modulus (G ′ ′) in the range of 70 ° C. to 100 ° C. of the resin component of the resin coating layer is from the viewpoint of the stability of the surface (coating surface) of the resin coating layer. It is preferably 0 × 10 ⁶ Pa or more and 1.0 × 10 ⁸ Pa or less, more preferably 2.0 × 10 ⁶ Pa or more and 8.4 × 10 ⁷ Pa or less.

If the minimum value of the storage elastic modulus (G ') and the loss elastic modulus (G'') in the range of 70 ° C. to 100 ° C. is not less than the above lower limit, the surface (coating surface) of the resin coating layer becomes difficult to soften. It becomes difficult for the decrease in the charge imparting ability to the toner and the adhesion of the toner itself due to the attachment derived from the toner.
On the other hand, if the minimum value of the storage elastic modulus (G ') and the loss elastic modulus (G'') is not more than the above upper limit, the magnetic carrier core is easily covered in the step of covering with the covering resin A and the covering resin B As a result, the surface (coating surface) of the resin coating layer tends to be smooth, and the output image is less likely to be affected.

When the glass transition temperature (Tg) of the coating resin A and the coating resin B is increased, the storage elastic modulus (G ′) of the resin component of the resin coating layer tends to increase. The Tg can be controlled by adjusting the types of monomers used in the synthesis of the coating resin A and the coating resin B, and the molecular weights of the coating resin A and the coating resin B. Therefore, the minimum value of the storage elastic modulus (G ′) in the range of 70 ° C. or more and 100 ° C. or less can be controlled by controlling the Tg of the coating resin A and the coating resin B, and the mixing ratio thereof.
In addition, when the polarity such as the acid value of the coating resin A and the coating resin B, the molecular weight, and the Tg are increased, the loss elastic modulus (G ′ ′) of the resin component of the resin coating layer tends to increase. The minimum value of the loss elastic modulus (G ′ ′) in the range of 100 ° C. or less can be controlled by adjusting the polarity, molecular weight and Tg of the coating resin A and the coating resin B.
Further, by mixing the resin for coating A and the resin for coating B, the storage elastic modulus (G ′) of the resin component of the resin coating layer and the loss elastic modulus (G) due to interactions such as hydrogen bonds between the molecules of the polymer In some cases, the storage elastic modulus (G ') and the loss elastic modulus (G ") of the resin component of the resin coating layer can be controlled.

<Amorphous resin>
The non-crystalline resin used in the toner of the present invention is not particularly limited, and it is possible to use the following polymer or resin.
For example, homopolymers of styrene and its substitution products such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene, etc .; Styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl Styrenic copolymers such as ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-acrylonitrile-indene copolymer; polyvinyl chloride, phenolic resin, natural resin modified phenolic resin, natural resin modified maleic resin ,acrylic resin, Methacrylic resins, polyvinyl acetate, silicone resins, polyester resins, polyurethane resins, polyamide resins, furan resins, epoxy resins, xylene resins, polyvinyl butyral, terpene resins, coumarone - indene resins, and petroleum resins.

Among these, from the viewpoint of low temperature fixability, it is preferable to use a polyester resin as a main component. The main component means that the content is 50% by mass or more. The amorphous resin is more preferably a polyester resin.
As monomers used for the polyester resin, polyhydric alcohols (dihydric or trivalent or higher alcohols), polyvalent carboxylic acids (divalent or trivalent or higher carboxylic acids), acid anhydrides thereof or lower alkyl esters thereof Is used.
Here, in order to produce a branched polymer, partial crosslinking in the molecule of the amorphous resin is effective, and for that purpose, it is preferable to use a trivalent or higher polyfunctional compound. Therefore, it is preferable to contain a trivalent or higher carboxylic acid, an acid anhydride thereof or a lower alkyl ester thereof, and / or a trivalent or higher alcohol as a raw material monomer of polyester.
The following monomers can be used as a polyhydric-alcohol monomer used for polyester resin.
Examples of the divalent alcohol component include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, bisphenol represented by formula (A) and derivatives thereof; diols represented by formula (B); It can be mentioned.

（式中、Ｒはエチレン又はプロピレン基であり、ｘ及びｙはそれぞれ０以上の整数であり、かつ、ｘ＋ｙの平均値は０以上１０以下である。）

(In the formula, R is ethylene or propylene, x and y are each an integer of 0 or more, and the average value of x + y is 0 or more and 10 or less.)

Examples of trihydric or higher alcohol components include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, and 1,2,4-butanetriol. 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene It can be mentioned.
Among these, glycerol, trimethylolpropane and pentaerythritol are preferably used. These dihydric alcohols and trihydric or higher alcohols may be used alone or in combination of two or more.

The following monomers can be used as a polyhydric carboxylic acid monomer used for polyester resin.
Examples of the divalent carboxylic acid component include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, malonic acid, n-dodecenylsuccinic acid, isododecenylsuccinic acid, n-dodecylsuccinic acid, isododecylsuccinic acid, n-octenylsuccinic acid, n-octylsuccinic acid, isooctenylsuccinic acid, isooctylsuccinic acid, anhydrides of these acids and the like These lower alkyl esters are mentioned.
Among these, maleic acid, fumaric acid, terephthalic acid and n-dodecenyl succinic acid are preferably used.

Examples of the trivalent or higher carboxylic acid, its acid anhydride or its lower alkyl ester include 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid and 1,2,4-naphthalenetricarboxylic acid 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra ( Methylene carboxyl) methane, 1,2,7,8-octane tetracarboxylic acid, pyromellitic acid, Empol trimer acid, acid anhydrides thereof, or lower alkyl esters thereof.
Among these, 1,2,4-benzenetricarboxylic acid, that is, trimellitic acid or a derivative thereof is particularly preferably used because it is inexpensive and the reaction control is easy. These divalent carboxylic acids and the like and trivalent or higher carboxylic acids can be used alone or in combination of two or more.

The method for producing the polyester resin is not particularly limited, and known methods can be used. For example, the above-mentioned alcohol monomer and carboxylic acid monomer are simultaneously charged and polymerized through an esterification reaction or a transesterification reaction and a condensation reaction to produce a polyester resin. The polymerization temperature is not particularly limited, but is preferably in the range of 180 ° C. or more and 290 ° C. or less.
In the polymerization of polyester, for example, a polyester resin polymerized using a tin-based catalyst which can use a polymerization catalyst such as a titanium-based catalyst, a tin-based catalyst, zinc acetate, antimony trioxide, germanium dioxide or the like is more preferable.

  The peak molecular weight of the amorphous resin is preferably 4,000 or more and 13,000 or less from the viewpoint of low-temperature fixability and hot offset resistance. The acid value of the amorphous resin is preferably 5 mgKOH / g or more and 20 mgKOH / g or less from the viewpoint of charge stability in a high temperature and high humidity environment. Furthermore, the hydroxyl value of the amorphous resin is preferably 20 mgKOH / g or more and 70 mgKOH / g or less from the viewpoint of low-temperature fixability and storage stability.

  In addition, as the amorphous resin, a low molecular weight amorphous resin C and a high molecular weight amorphous resin D may be mixed and used. The low-temperature fixability and the hot offset resistance that the content ratio (C / D) of low molecular weight amorphous resin C to high molecular weight amorphous resin D is 60/40 or more and 90/10 or less on a mass basis It is preferable from the viewpoint of sex.

The peak molecular weight of the low molecular weight amorphous resin C is preferably 4,000 or more and 7,000 or less from the viewpoint of low temperature fixability. The acid value of the low molecular weight non-crystalline resin C is preferably 20 mg KOH / g or less from the viewpoint of charge stability in a high temperature and high humidity environment.
It is preferable from the viewpoint of hot offset resistance that the peak molecular weight of the high molecular weight amorphous resin D is more than 7,000 and not more than 20,000. The acid value of the high molecular weight binder resin is preferably 15 mg KOH / g or more and 30 mg KOH / g or less from the viewpoint of charge stability in a high temperature and high humidity environment.

<Crystalline resin>
For the toner particles, a crystalline resin may be used. A crystalline resin is a resin in which an endothermic peak is observed in differential scanning calorimetry (DSC).
The crystalline resin is not particularly limited, but it is preferable to use a polyester resin as a main component from the viewpoint of low temperature fixability.
The crystalline polyester is preferably obtained by subjecting a monomer composition containing an aliphatic diol having 2 to 22 carbon atoms and an aliphatic dicarboxylic acid having 2 to 22 carbon atoms as a main component to a polycondensation reaction.

The aliphatic diol having 2 to 22 carbon atoms (more preferably 6 to 12 carbon atoms) is not particularly limited, but is preferably a linear (more preferably linear) aliphatic diol.
For example, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, 1,4-butanediol, 1,4-butadiene glycol, trimethylene glycol, tetramethylene glycol And pentamethylene glycol, hexamethylene glycol, octamethylene glycol, nonamethylene glycol, decamethylene glycol and neopentyl glycol.
Among these, particularly preferred are linear aliphatics such as ethylene glycol, diethylene glycol, 1,4-butanediol, and 1,6-hexanediol, and α, ω-diols.
Among the above-mentioned alcohol components, preferably 50% by mass or more, more preferably 70% by mass or more is an alcohol selected from aliphatic diols having 2 to 22 carbon atoms.

  Polyhydric alcohol monomers other than the above aliphatic diols can also be used. Among the polyhydric alcohol monomers, examples of the dihydric alcohol monomer include aromatic alcohols such as polyoxyethylenated bisphenol A and polyoxypropyleneated bisphenol A; 1,4-cyclohexanedimethanol and the like. Moreover, as a polyhydric alcohol monomer of trivalent or more among the polyhydric alcohol monomers, aromatic alcohols such as 1,3,5-trihydroxymethylbenzene; pentaerythritol, dipentaerythritol, tripentaerythritol Fats such as 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane and the like Family alcohol and the like.

  Furthermore, you may use monovalent alcohol to such an extent that the characteristic of crystalline polyester is not impaired. Examples of the monohydric alcohol include monoalcohols such as n-butanol, isobutanol, sec-butanol, n-hexanol, n-octanol, 2-ethylhexanol, cyclohexanol and benzyl alcohol.

On the other hand, the aliphatic dicarboxylic acid having 2 to 22 carbon atoms (more preferably 6 to 12 carbon atoms) is not particularly limited, but is preferably a linear (more preferably linear) aliphatic dicarboxylic acid .
Specific examples thereof include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, speric acid, glutaconic acid, azelaic acid, sebacic acid, nonane dicarboxylic acid, decanedicarboxylic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, Examples thereof include maleic acid, fumaric acid, mesaconic acid, citraconic acid and itaconic acid, and also include those obtained by hydrolyzing these acid anhydrides or lower alkyl esters.
Among the above-mentioned carboxylic acid components, preferably 50% by mass or more, more preferably 70% by mass or more is a carboxylic acid selected from aliphatic dicarboxylic acids having 2 to 22 carbon atoms.

Polyvalent carboxylic acids other than the above-mentioned aliphatic dicarboxylic acids having 2 to 22 carbon atoms can also be used. Among the other polyvalent carboxylic acid monomers, as a divalent carboxylic acid, aromatic carboxylic acids such as isophthalic acid and terephthalic acid; aliphatic carboxylic acids of n-dodecylsuccinic acid and n-dodecenylsuccinic acid; cyclohexanedicarboxylic acid Alicyclic carboxylic acids such as acids and the like, and acid anhydrides or lower alkyl esters thereof are also included.
Among the other carboxylic acid monomers, trivalent or higher polyvalent carboxylic acids include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, 1, Aromatic carboxylic acids such as 2,4-naphthalenetricarboxylic acid, pyromellitic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2 -Aliphatic carboxylic acids such as methylenecarboxypropane and the like, and derivatives thereof such as acid anhydrides or lower alkyl esters thereof are also included.

  Furthermore, you may contain a monovalent | monohydric carboxylic acid to such an extent that the characteristic of crystalline polyester is not impaired. Examples of monovalent carboxylic acids include benzoic acid, naphthalenecarboxylic acid, salicylic acid, 4-methylbenzoic acid, 3-methylbenzoic acid, phenoxyacetic acid, biphenylcarboxylic acid, monocarboxylic acids such as acetic acid, propionic acid, butyric acid and octanoic acid An acid is mentioned.

In addition, the crystalline polyester resin is a crystalline polyester resin in which one or more aliphatic compounds selected from the group consisting of aliphatic monocarboxylic acids having 10 to 20 carbon atoms and aliphatic monoalcohols are condensed at the ends of molecular chains. It is preferable from the viewpoint of low temperature fixability and preservability.
Generally, in recrystallization of crystalline polyester, crystals grow from the crystal nucleus as a starting point. Therefore, by condensing one or more aliphatic compounds selected from the group consisting of aliphatic monocarboxylic acids having 10 to 20 carbon atoms and aliphatic monoalcohols at the end of the molecular chain, these become crystal nuclei and recrystallization Can be promoted to improve the storage stability.
Further, when the carbon number is in the above range, it is easy to condense at the end of the molecular chain, and since it does not exist as a free monomer, it is preferable from the viewpoint of preservation. When the number of carbon atoms is in the above range, the compatibility between the crystalline polyester and the amorphous resin is not impaired, which is preferable from the viewpoint of low-temperature fixability.

  Furthermore, the amount of use of one or more aliphatic compounds selected from the group consisting of aliphatic monocarboxylic acids having 10 to 20 carbon atoms and aliphatic monoalcohols is 1.0 mol% in the raw material monomers of the crystalline polyester resin It is preferable that it is 10.0 mol% or less, and it is more preferable that it is 4.0 mol% or more and 8.0 mol% or less. It is preferable that the amount of the aliphatic compound is in the above range, because an appropriate amount of crystal nuclei can be present without inhibiting the low temperature fixability.

Examples of aliphatic monocarboxylic acids having 10 to 20 carbon atoms include capric acid (decanoic acid), undecylic acid, lauric acid (dodecanoic acid), tridecylic acid, myristylic acid (tetradecanoic acid), pentadecylic acid, palmitic acid (hexadecanoic acid) And margaric acid (heptadecanoic acid), stearic acid (octadecanoic acid), nonadecylic acid and arachidic acid (icosanic acid).
Examples of aliphatic monoalcohols having 10 or more and 20 or less carbon atoms include capryl alcohol (decanol), undecanol, lauryl alcohol (dodecanol), tridecanol, myristyl alcohol (tetradecanol), pentadecanol, palmityl alcohol (hexadecanol) Margaryl alcohol (heptadecanol), stearyl alcohol (octadecanol), nonadecanol, arachidyl alcohol (icosanol).

The content of the crystalline polyester resin is preferably 3 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the amorphous resin from the viewpoints of low temperature fixability and chargeability under high temperature and high humidity environment.
Crystalline polyester can be produced according to a conventional polyester synthesis method. For example, after the esterification reaction or transesterification reaction of the above-mentioned carboxylic acid monomer and alcohol monomer, the crystalline polyester is obtained by polycondensation reaction according to a conventional method under reduced pressure or by introducing nitrogen gas. You can get it. Thereafter, the above-mentioned aliphatic compound is further added to carry out an esterification reaction, whereby a desired crystalline polyester can be obtained.

The esterification or transesterification reaction can be carried out using a conventional esterification catalyst or transesterification catalyst such as sulfuric acid, titanium butoxide, dibutyltin oxide, manganese acetate, magnesium acetate and the like, if necessary.
The polycondensation reaction may be carried out using a conventional polymerization catalyst, for example, a known catalyst such as titanium butoxide, dibutyltin oxide, tin acetate, zinc acetate, tin disulfide, antimony trioxide and germanium dioxide. . The polymerization temperature and the amount of catalyst are not particularly limited, and may be determined appropriately.
In the esterification or transesterification reaction or polycondensation reaction, in order to increase the strength of the obtained crystalline polyester, all monomers are charged at once or in order to reduce low molecular weight components, first, a bivalent monomer is reacted After the reaction, a method of adding and reacting a trivalent or higher monomer may be used.

<Polymer in which styrene acrylic polymer is graft-polymerized to polyolefin>
The wax dispersant has a polymer in which a styrene acrylic polymer is graft-polymerized to polyolefin (hereinafter also referred to as a graft polymer). Besides the graft polymer, other wax dispersants may be used as wax dispersants to the extent that the effects of the present invention are not impaired. The wax dispersant is preferably a polymer in which a styrene acrylic polymer is graft-polymerized to a polyolefin.
As for the polyolefin used for a graft polymer, it is preferable that the peak temperature of the largest class heat peak measured using a differential scanning calorimeter (DSC) is 60 degreeC or more and 110 degrees C or less. Moreover, it is preferable that polyolefin has a weight average molecular weight (Mw) of 900 or more and 50000 or less.
The polyolefin is not particularly limited as long as it is a polymer or copolymer of unsaturated hydrocarbon having one double bond, and various polyolefins can be used. In particular, polyethylene and polypropylene are preferably used. Moreover, it is more preferable to have a branched structure like a polypropylene from a reactive viewpoint at the time of manufacture of a graft polymer.
The content of the polyolefin is preferably 5.0% by mass or more and 20.0% by mass or less, and more preferably 8.0% by mass or more and 12.0% by mass, in the polymer in which the styrene acrylic polymer is graft-polymerized to the polyolefin. It is more preferable that the content is at most mass%.

In the present invention, the method of graft polymerizing a styrene acrylic polymer to polyolefin is not particularly limited, and a conventionally known method can be used.
The styrene acrylic polymer is not particularly limited as long as it has a structure derived from a saturated alicyclic compound. Preferably, the styrene acrylic polymer has monomer units derived from cycloalkyl (meth) acrylate. Here, the monomer unit refers to a reacted form of the monomer substance in the polymer.
As the cycloalkyl (meth) acrylate, for example, the following cycloalkyl (meth) acrylate monomer (a) can be used.

Cyclopropyl acrylate, cyclobutyl acrylate, cyclopentyl acrylate, cyclohexyl acrylate, cycloheptyl acrylate, cyclooctyl acrylate, cyclopropyl methacrylate, cyclobutyl methacrylate, cyclobutyl methacrylate, cyclopentyl methacrylate, cyclohexyl methacrylate, cycloheptyl methacrylate, cyclooctyl methacrylate, dihydrocyclopentadiethyl acrylate, Dicyclopentanyl acrylate, dicyclopentanyl methacrylate and the like can be mentioned.
Among these, at least one selected from the group consisting of cyclohexyl acrylate, cycloheptyl acrylate, cyclooctyl acrylate, cyclohexyl methacrylate, cycloheptyl methacrylate and cyclooctyl methacrylate is preferable from the viewpoint of hydrophobicity. These may be used alone or in combination of two or more.

  Besides the cycloalkyl (meth) acrylate monomer (a), other monomers (b) may be used for the styrene acrylic polymer. For example, styrene-based monomers such as styrene, α-methylstyrene, p-methylstyrene, m-methylstyrene, p-methoxystyrene, p-hydroxystyrene, p-acetoxystyrene, vinyltoluene, ethylstyrene, phenylstyrene and benzylstyrene Alkyl esters of unsaturated carboxylic acids such as methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate (the carbon number of the alkyl is 1 or more and 18 or less); Vinyl ester monomers such as vinyl acetate; vinyl ether monomers such as vinyl methyl ether; halogen element-containing vinyl monomers such as vinyl chloride; Include diene monomers such as isobutylene. A plurality of these may be used.

The acid value of the graft polymer is preferably 5 mg KOH / g or more and 50 mg KOH / g or less, and more preferably 15 mg KOH / g or more and 35 mg KOH / g or less.
When the acid value is within the above range, the affinity to the wax and the hydrophobicity of the graft polymer itself can be compatible, so the surface is kept hydrophobic and it is easy to prevent white spots.

  The molecular weight distribution of the graft polymer by gel permeation chromatography (GPC) preferably has a weight average molecular weight (Mw) of 5,000 or more and 70000 or less, and more preferably 10,000 or more and 50000 or less. When the weight average molecular weight (Mw) is in the above range, the mechanical strength of the toner particle surface is increased, and embedding of the external additive during durable use is suppressed, so that the effects of charging stability and whitening prevention are obtained. Cheap.

  It is preferable that content of a graft polymer is 3.0 mass parts or more and 10.0 mass parts or less with respect to 100 mass parts of amorphous resin. When the content is in this range, the hydrophobicity of the graft polymer is also exhibited in the toner, and the amount of adsorbed water in a high temperature and high humidity environment is reduced, whereby the charge maintenance property is improved. Further, the fine dispersion of the crystalline resin in the amorphous resin by the graft polymer of the styrene acrylic polymer in the polyolefin is improved, and the low temperature fixing property is improved.

<Wax>
Examples of the wax used for the toner of the present invention include the following.
Low molecular weight polyethylene, low molecular weight polypropylene, alkylene copolymer, microcrystalline wax, paraffin wax, hydrocarbon wax such as Fischer-Tropsch wax; oxide of hydrocarbon wax such as oxidized polyethylene wax or block copolymer thereof Waxes based on fatty acid esters such as carnauba wax; Deoxidized fatty acid esters such as deacidified carnauba wax partially or entirely.
Further, the following may be mentioned. Saturated linear fatty acids such as palmitic acid, stearic acid and montanic acid; unsaturated fatty acids such as brashidic acid, eleostearic acid and valinaric acid; stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnavir alcohol, seryl alcohol Saturated alcohols such as melysyl alcohol; polyhydric alcohols such as sorbitol; fatty acids such as palmitic acid, stearic acid, behenic acid, montanic acid, stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnavir alcohol Esters with alcohols such as ceryl alcohol and melysyl alcohol; fatty acid amides such as linoleic acid amide, oleic acid amide and lauric acid amide; methylenebisstearic acid amide, ethylene Saturated fatty acid bisamides such as scapric acid amide, ethylene bis lauric acid amide, hexamethylene bis stearic acid amide; ethylene bis oleic acid amide, hexamethylene bis oleic acid amide, N, N 'dioleyl adipic acid amide, N, N Unsaturated fatty acid amides such as dioleyl sebacic acid amide; aromatic bisamides such as m-xylene bis-stearic acid amide, N, N 'distearyl isophthalic acid amide; calcium stearate, calcium laurate, zinc stearate Aliphatic metal salts such as magnesium stearate (generally referred to as metal soaps); waxes grafted with aliphatic hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid; behenine Acid monoglyceride Una fatty acids with polyhydric alcohols of the partial ester; methyl ester compounds having hydroxyl groups obtained by hydrogenation of vegetable fats and oils.

Among these waxes, paraffin wax, hydrocarbon wax such as Fischer-Tropsch wax, or fatty acid ester wax such as carnauba wax are preferable from the viewpoint of improving low-temperature fixability and fixability. In the present invention, hydrocarbon-based waxes are more preferable in that the hot offset resistance is further improved.
The content of the wax is preferably 1 part by mass or more and 15 parts by mass or less per 100 parts by mass of the amorphous resin.
In the endothermic curve at the time of temperature rise measured with a differential scanning calorimetry (DSC) device, the peak temperature of the maximum endothermic peak of the wax is preferably 45 ° C. or more and 140 ° C. or less. It is preferable that the peak temperature of the maximum endothermic peak of the wax is in the above-mentioned range since both the storage stability of the toner and the hot offset resistance can be achieved.

<Colorant>
A colorant may be used for the toner particles. Examples of the colorant include the following.
Examples of the black colorant include carbon black; those toned in black using a yellow colorant, a magenta colorant and a cyan colorant. Although a pigment may be used alone as the colorant, it is more preferable from the viewpoint of the image quality of a full color image to improve the sharpness by using a dye and a pigment in combination.
As pigments for magenta toners, the following may be mentioned. 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, 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, 146, 147, 150, 163, 184, 202, 206, 207, 209, 238, 269, 282; I. Pigment violet 19; C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35.
Examples of the magenta toner dye include the following. C. I. Solvent red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121; I. Disperse thread 9; C.I. I. Solvent violet 8, 13, 14, 21, 27; C.I. I. Oil-soluble dyes such as Disperse Violet 1, C.I. 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; I. Basic dyes such as Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28.

Examples of pigments for cyan toner include the following. C. I. Pigment blue 2, 3, 15: 2, 15: 3, 15: 4, 16, 17; C.I. I. Bat Blue 6; C.I. I. Acid Blue 45, a copper phthalocyanine pigment in which 1 to 5 phthalimidomethyl groups are substituted to a phthalocyanine skeleton.
As dyes for cyan toner, C.I. I. There is a solvent blue 70.
Examples of pigments for yellow toners include the following. 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; I. Bat Yellow 1, 3, 20.
As dyes for yellow toner, C.I. I. There is a solvent yellow 162.
The content of the coloring agent is preferably 0.1 parts by mass to 30 parts by mass with respect to 100 parts by mass of the amorphous resin.

<Charge control agent>
The toner can also contain a charge control agent, if necessary. As the charge control agent, known ones can be used, but in particular, a metal compound of an aromatic carboxylic acid which is colorless, can accelerate the charging speed of the toner and can stably hold a constant charge amount is preferable.
As a negative charge control agent, metal compounds of salicylic acid, metal compounds of naphthoic acid, metal compounds of dicarboxylic acid, polymeric compounds having sulfonic acid or carboxylic acid in side chain, sulfonic acid salt or ester of sulfonic acid in side chain Examples thereof include polymer type compounds, polymer type compounds having a carboxylate or a carboxylic acid ester in the side chain, boron compounds, urea compounds, silicon compounds, and calixarenes.
Examples of positive charge control agents include quaternary ammonium salts, polymer type compounds having the quaternary ammonium salt in the side chain, guanidine compounds and imidazole compounds.
The charge control agent may be internally or externally added to the toner particles. The addition amount of the charge control agent is preferably 0.05 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the amorphous resin.

<Inorganic fine particles>
The toner can also contain inorganic fine particles as needed. The inorganic fine particles may be internally added to the toner particles or may be mixed with the toner particles as an external additive. The external additive is preferably an inorganic fine powder such as silica, titanium oxide or aluminum oxide. The inorganic fine powder is preferably hydrophobized with a hydrophobizing agent such as a silane compound, silicone oil or a mixture thereof.
As the external additive for improving the flowability, an inorganic fine powder having a specific surface area of 50 m ² / g or more and 400 m ² / g or less is preferable. In order to stabilize the durability, an inorganic fine powder having a specific surface area of 10 m ² / g or more and 50 m ² / g or less is preferable. In order to make flowability improvement and durability stability compatible, you may use together the inorganic fine powder whose specific surface area is the said range.
The external additive is preferably used in an amount of 0.1 parts by mass or more and 10.0 parts by mass or less with respect to 100 parts by mass of the toner particles. A known mixer such as a Henschel mixer can be used to mix the toner particles with the external additive.

<Magnetic carrier>
The magnetic carrier has a magnetic carrier core and a resin coating layer formed on the surface of the magnetic carrier core. Then, the resin coating layer contains a coating resin A and a coating resin B, and the coating resin A is a monomer (or monomer composition) containing a (meth) acrylic acid ester monomer having an alicyclic hydrocarbon group. ) Polymer.
Examples of (meth) acrylic acid ester monomers having an alicyclic hydrocarbon group used for the coating resin A include, for example,
Cyclobutyl acrylate, cyclopentyl acrylate, cyclohexyl acrylate, cycloheptyl acrylate, dicyclopentenyl acrylate, dicyclopentanyl acrylate, cyclobutyl methacrylate, cyclopentyl methacrylate, cyclohexyl methacrylate, cycloheptyl methacrylate, dimethacrylate methacrylate Cyclopentenyl, dicyclopentanyl methacrylate and the like can be mentioned. One of these monomers may be used alone, or two or more thereof may be used.

At the time of synthesis of the coating resin A, the amount of (meth) acrylic acid ester monomer having an alicyclic hydrocarbon group is 50% by mass or more and 90% by mass or less in all the monomers used for the synthesis of the coating resin A Is preferred.
The weight average molecular weight (Mw) of the coating resin A is preferably 20,000 or more and 120,000 or less, and more preferably 30,000 or more and 100,000 or less, from the stability of the coating.

The acid value of the coating resin A is preferably 0 mg KOH / g or more and 3.0 mg KOH / g or less, more preferably 0 mg KOH / g or more and 2.8 mg KOH / g or less, and 0 mg KOH / g or more and 2.5 mg KOH / g. More preferably, it is g or less.
When the acid value of the coating resin A is 3.0 mgKOH / g or less, self-aggregation of the resin due to the influence of the acid value is less likely to occur, and the smoothness of the surface (coating surface) of the resin coating layer is less likely to decrease. . The acid value of the coating resin A can be controlled by using a monomer having a polar group such as a carboxy group or a sulfo group (sulfonic acid group) at the time of synthesis of the coating resin A and adjusting the addition amount of the monomer. Since the acid value of the coating resin A is preferably low, it is preferable not to use a monomer having a polar group in the polymer of the coating resin A. Even when the resin is synthesized using only the monomer forming the ester bond, a slight acid value may be generated in the synthesized resin. It is considered that this is because when the resin is synthesized (at the time of polymerization), a part of the ester bond is decomposed to generate a carboxy group.

The coating resin A is preferably a polymer (copolymer) of a monomer composition containing a (meth) acrylic acid ester monomer having an alicyclic hydrocarbon group and a macromonomer. When a macromonomer is used for the synthesis of the coating resin A, the adhesion between the resin coating layer and the magnetic carrier core is improved and the charge imparting ability of the magnetic carrier to the toner is improved.
The above macromonomer is
At least one polymer selected from the group consisting of methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, styrene, acrylonitrile and methacrylonitrile Is preferred.

The weight average molecular weight (Mw) of the macromonomer is preferably 2000 or more and 10000 or less, and more preferably 3000 or more and 8000 or less.
In the synthesis of the coating resin A, the amount of the macromonomer is preferably 5.0% by mass or more and 40.0% by mass or less in the total monomers used for the synthesis of the coating resin A.

The coating resin B is a polymer of a monomer (or monomer composition) containing a (meth) acrylic monomer having a polar group.
The acid value of the coating resin B is preferably 4.0 mg KOH / g or more and 50.0 mg KOH / g or less. If the acid value is 4.0 mg KOH / g or more, the adhesion between the resin coating layer and the magnetic carrier core is improved, the charge imparting ability to the toner is stabilized, and the charge amount given to the toner fluctuates even if the environment fluctuates. It becomes difficult. When the acid value is 50.0 mg KOH / g or less, the resin coating layer hardly absorbs moisture, and the charge imparting ability to the toner is stabilized, and the image density and the like become stable even under long-term use, particularly under high temperature and high humidity environment. .

The (meth) acrylic monomer used for the synthesis of the coating resin B has a polar group that imparts an acid value to the coating resin B. As a polar group which gives an acid value to resin B for coating | cover, a carboxy group, a sulfo group, etc. are mentioned, for example. As the (meth) acrylic monomer having such a polar group, for example, acrylic acid, methacrylic acid and the like are preferable.
The acid value of the coating resin B is increased by increasing the proportion of monomers having a polar group such as acrylic acid and methacrylic acid in all the monomers used for the synthesis of the coating resin B. Therefore, the acid value of the resin B for coating can be controlled by adjusting the ratio of the monomer which has a polar group, and the monomer which does not do so.
The weight average molecular weight (Mw) of the coating resin B is preferably 25,000 or more and 120,000 or less, and more preferably 30,000 or more and 100,000 or less, from the viewpoint of the stability of the coating.

When the resin for coating A and the resin for coating B are coated on the surface of the magnetic carrier core (for example, when preparing a resin solution for coating), a better effect can be exhibited by mixing the both resins, which is preferable. That is, the resin coating layer is preferably a mixed resin of the resin for coating A and the resin for coating B. The strength of the resin coating layer (film strength) in the case where the resin for coating A and the resin for coating B are mixed, as compared to the case where the resin for coating A and the resin for coating B are individually coated on the magnetic carrier core. Was found to be higher.
As to the reason, the adhesion between the molecules of the polymer is increased by the electron donating property of the alicyclic hydrocarbon group of the coating resin A and the electron withdrawing property of the polar group of the coating resin B, The present inventors infer that the strength (coating film strength) is increased.

If one polymer molecule contains an alicyclic hydrocarbon group and a polar group for giving an acid value,
In the case of co-presence, self-aggregation of the resin (polymer) tends to occur. Therefore, the surface (coating surface) of the resin coating layer is smoothed by using the coating resin A and the coating resin B as in the present invention, rather than including such a polymer in the resin coating layer. The effect and the effect of sufficiently adhering the resin coating layer to the magnetic carrier core can be easily obtained.
In the present invention, it is particularly preferable to mix the coating resin A and the coating resin B immediately before coating the magnetic carrier core. As a result, the aggregation of the coating resin A and the coating resin B can be reduced, and even if the image forming apparatus (copier) continues to be used under severe usage conditions such as environmental fluctuations and continuous image output, The toner enables stable charging.

In the coating resin A, a monomer (or a monomer composition) containing a (meth) acrylic acid ester monomer having an alicyclic hydrocarbon group is other than the above (meth) acrylic acid ester having an alicyclic hydrocarbon group. And other (meth) acrylic monomers may be included.
Moreover, in the resin B for coating | cover, the monomer (or monomer composition) containing the (meth) acrylic-type monomer which has a polar group is other (meth) acryl-type other than the (meth) acrylic-type monomer which has the said polar group. It may contain a monomer.
Examples of these other (meth) acrylic monomers include the following.
For example, acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, normal butyl acrylate, isobutyl acrylate, tert-butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, acrylic Acid tridecyl, tetradecyl acrylate, pentadecyl acrylate, hexadecyl acrylate, heptadecyl acrylate, octadecyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, isopropyl methacrylate, normal butyl methacrylate, methacrylate Isobutyl, tert-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, dodecyl methacrylate, tride methacrylate Le, tetradecyl methacrylate, pentadecyl methacrylate, hexadecyl methacrylate acid and methacrylic acid heptadecyl and octadecyl methacrylate.

  The magnetic carrier core is not particularly limited, and commonly used conventional ones such as ferrite particles can be used. Among them, preferable magnetic carrier cores are magnetic substance dispersion type resin particles in which a magnetic substance component is dispersed in a resin component, and porous magnetic core particles containing a resin in a pore portion. These can reduce the true density of the magnetic carrier, and thus can further suppress the load on the toner. As a result, even when used for a long time, the image quality is less likely to be degraded, and it is possible to reduce the frequency of replacement of the developer having a toner and a carrier (two-component developer).

The magnetic substance dispersed resin particles will be described. The porous magnetic core particles will be described later.
The magnetic substance component contained in the magnetic substance-dispersed resin particle is, for example, a magnetite particle, a maghemite particle, or an oxide of silicon, a hydroxide of silicon, a hydroxide of aluminum, an oxide of aluminum and a hydroxide of aluminum. Magnetic iron oxide particles containing at least one selected from the group; magnetoplumbite type ferrite particles containing barium, strontium or barium and strontium; selected from the group consisting of manganese, nickel, zinc, lithium and magnesium And spinel ferrite particles containing at least one of the following. Among these, magnetic iron oxide particles are preferable.

In addition to the above-mentioned magnetic components, nonmagnetic iron oxide particles such as hematite particles, nonmagnetic hydrous ferric oxide particles such as goethite particles, titanium oxide particles, silica particles, and the like in the magnetic material dispersed resin particles. Nonmagnetic components (nonmagnetic inorganic compound particles) such as talc particles, alumina particles, barium sulfate particles, barium carbonate particles, cadmium yellow particles, calcium carbonate particles and zinc oxide particles can also be used in combination.
When the magnetic component and the nonmagnetic component (nonmagnetic inorganic compound particles) are used in combination, the ratio of the magnetic component in these mixtures is preferably 30% by mass or more.

It is preferable that all or part of the magnetic component is treated with a lipophilic agent.
As a lipophilic treatment agent, for example, at least one functional group selected from the group consisting of an epoxy group, an amino group, a mercapto group, an organic acid group, an ester group, a ketone group, a halogenated alkyl group and an aldehyde group And organic compounds having these and mixtures thereof.
As the organic compound having a functional group, a coupling agent is preferred. A silane coupling agent, a titanium coupling agent and an aluminum coupling agent are more preferable, and a silane coupling agent is more preferable.

As a resin component which comprises magnetic substance dispersion type resin particles, thermosetting resin is preferred.
As a thermosetting resin, a phenol resin, an epoxy resin, unsaturated polyester resin etc. are mentioned, for example. Among these, phenol resins are preferable from the viewpoint of easy availability (price and ease of production). As a phenol resin, phenol-formaldehyde resin is mentioned, for example.
The ratio of the resin component to the magnetic material component constituting the magnetic material-dispersed resin particles is preferably such that the resin component is 1% by mass or more and 20% by mass or less. The ratio of the magnetic substance component and the nonmagnetic inorganic compound particles contained as necessary is preferably 80% by mass or more and 99% by mass or less based on the total mass of the magnetic substance-dispersed resin particles.

<Developer>
The carrier mixing ratio of the two-component developer is preferably 2% by mass to 15% by mass, and more preferably 4% by mass to 13% by mass, as the toner concentration in the two-component developer. Within this range, good results are usually obtained.

<Manufacturing method>
The method for producing toner particles is not particularly limited, and known methods such as a grinding method and a polymerization method can be used. Preferably it is a grinding method. In the pulverizing method, a resin component such as an amorphous resin and a crystalline resin as needed, a wax, a wax dispersant, and a colorant as needed are melt-kneaded, and the kneaded product is cooled and then crushed and classified.
Hereinafter, the toner production procedure in the pulverization method will be described.
In the raw material mixing step, as a material constituting toner particles, for example, amorphous resin and resin component such as crystalline resin as required, wax, wax dispersant, colorant as necessary, charge control agent, etc. A predetermined amount of the other components are weighed, blended, and mixed. Examples of the mixing apparatus include a double con mixer, a V-type mixer, a drum mixer, a super mixer, a Henschel mixer, a Nauta mixer, and a mechano hybrid (manufactured by Nippon Coke Industry Co., Ltd.).

Next, the mixed material is melt-kneaded to disperse wax and the like in the resin component. In the melt-kneading process, a batch-type kneader such as a pressure kneader or a Banbury mixer, or a continuous-type kneader can be used, and a single- or twin-screw extruder is mainly used because of its superiority of continuous production. It has become.
For example, a KTK type twin screw extruder (made by Kobe Steel, Ltd.), a TEM type twin screw extruder (made by Toshiba Machine Co., Ltd.), a PCM kneader (made by Ikegai Iron Works), a twin screw extruder (made by Kay C.K. And Ko Kneader (manufactured by Bus Co., Ltd.) and Niedex (manufactured by Japan Coke Industry Co., Ltd.). Furthermore, the resin composition obtained by melt-kneading may be rolled by a two-roll mill or the like, and may be cooled by water or the like in the cooling step.

The cooled resin composition is then ground to the desired particle size in the grinding step. In the grinding process, for example, after coarsely grinding with a grinder such as crusher, hammer mill, feather mill, etc., for example, Cryptron system (manufactured by Kawasaki Heavy Industries, Ltd.), superrotor (manufactured by Nisshin Engineering), turbo, Milled with a mill (manufactured by Turbo Kogyo Co., Ltd.) or an air jet type pulverizer.
After that, if necessary, inertial classification type elbow jet (made by Nittetsu Mining Co., Ltd.), centrifugal force classification type Turboplex (made by Hosokawa Micron), TSP separator (made by Hosokawa Micron), Faculty (made by Hosokawa Micron) Classify using a classifier or sieving machine.

Thereafter, surface treatment of the toner particles by heating may be performed. Thereby, the circularity of the toner can be increased. For example, surface treatment can be performed by hot air using the surface treatment apparatus shown in FIG. The toner particles are preferably heat-treated toner particles.
The mixture quantitatively supplied by the raw material quantitative supply means 1 is introduced to the introduction pipe 3 installed on the vertical line of the raw material supply means by the compressed gas adjusted by the compressed gas adjustment means 2. The mixture having passed through the introduction pipe is uniformly dispersed by the conical projection-like member 4 provided at the central portion of the raw material supply means, and is introduced into the radially extending eight-direction supply pipes 5 to perform the heat treatment. Led to
At this time, the flow of the mixture supplied to the processing chamber is restricted by the restriction means 9 for restricting the flow of the mixture provided in the processing chamber. For this reason, the mixture supplied to the processing chamber is cooled after being heat-treated while swirling in the processing chamber.

Hot air for heat treatment of the supplied mixture is supplied from the hot air supply means 7, and is swirled and introduced into the processing chamber by the turning member 13 for turning the hot air. As the structure, the turning member 13 for turning the hot air has a plurality of blades, and the turning of the hot air can be controlled by the number and angle of the blades. The temperature of the hot air supplied into the processing chamber at the outlet of the hot air supply means 7 is preferably 100 ° C. to 300 ° C. If the temperature at the outlet of the hot air supply means is within the above range, toner particles can be uniformly sphericized while preventing fusion or coalescence of the toner particles due to excessive heating of the mixture. Become.
The thermally treated toner particles are further cooled by the cold air supplied from the cold air supply means 8. The temperature of the cold air supplied from the cold air supply means 8 is preferably -20 ° C to 30 ° C. If the temperature of the cold air is within the above range, the heat-treated toner particles can be efficiently cooled, and fusion or coalescence of the heat-treated toner particles is prevented without inhibiting uniform spheroidization of the mixture. be able to. The absolute moisture content of cold air is preferably 0.5 g / m ³ or more and 15.0 g / m ³ or less.

Next, the cooled heat-treated toner particles are collected by the collection means 10 at the lower end of the processing chamber. A blower (not shown) is provided at the end of the recovery means, and it is configured to be suctioned and transported by it.
Further, the powder particle supply port 14 is provided such that the swirling direction of the supplied mixture and the swirling direction of the hot air are the same, and the collection means 10 of the surface treatment apparatus is of the swirled powder particles. It is provided on the outer periphery of the processing chamber so as to maintain the turning direction. Furthermore, the cold air supplied from the cold air supply means 8 is configured to be supplied horizontally and tangentially from the apparatus outer peripheral portion to the peripheral surface of the processing chamber. The swirling direction of toner particles supplied from the powder supply port, the swirling direction of cold air supplied from the cold air supply means, and the swirling direction of hot air supplied from the hot air supply means are all the same. Therefore, turbulent flow does not occur in the processing chamber, the swirling flow in the apparatus is enhanced, strong centrifugal force is applied to the toner particles, and the dispersibility of the toner particles is further improved. Toner particles can be obtained.

The average circularity of the toner particles is preferably 0.950 or more and 0.980 or less, more preferably 0.960 or more and 0.980 or less. It is preferable that the content is in the above range, because the transferability is improved and the cleaning ability can be compatible.
The toner particles may be used as a toner as it is, or, if necessary, an external additive may be added to the surface of the toner particles to make a toner. As a method of adding external additives, toner particles and various known external additives are compounded in predetermined amounts, and double con mixer, V type mixer, drum type mixer, super mixer, Henschel mixer, Nauta mixer, mechano hybrid ( The method of stirring and mixing using mixing apparatuses, such as Nippon Coke Kogyo Co., Ltd.) and Nobilta (made by Hosokawa Micron Corporation), is used as an external adder.

Examples of the method for producing the magnetic substance-dispersed resin particles include the methods described in Examples described later. For example, first, phenols and aldehydes are stirred in an aqueous medium in the presence of a magnetic component such as magnetic iron oxide particles and a basic catalyst. Then, it is the method of making phenols and aldehydes react and making it harden, and manufacturing magnetic body dispersion type resin particles containing magnetic body components, such as magnetic iron oxide particles, and phenol resin.
Further, magnetic substance dispersed resin particles can also be produced by a method of grinding a resin containing a magnetic substance component such as magnetic iron oxide particles, so-called kneading and pulverizing method.
The former method is preferred from the viewpoint of easy control of the particle size of the magnetic carrier and sharpening of the particle size distribution of the magnetic carrier.

Next, porous magnetic core particles will be described.
Examples of the material of the porous magnetic core particle include magnetite and ferrite. Among them, ferrite is preferable from the viewpoint of the ease of control of the porous structure of the porous magnetic core particles and the ease of adjustment of the resistance of the porous magnetic core particles.
Ferrite is a sintered body represented by the following general formula.
(M1 ₂ O) _x (M ₂ O) _y (Fe ₂ O ₃ ) _z
(In the above general formula, M1 is a monovalent metal, M2 is a divalent metal, and when x + y + z = 1.0, 0 ≦ x ≦ 0.8, 0 ≦ y ≦ 0.8 and 0 .2 <z <1.0)
In the above general formula, as M1 or M2, for example, Li, Fe, Mn, Mg, Sr, Cu, Zn, Ca, Ni, Co, Ba, Y, V, Bi, In, Ta, Zr, B, Mo Na, Sn, Ti, Cr, Al, Si, rare earths and the like.

In the porous magnetic core particle, in order to maintain the amount of magnetization appropriately and to set the pore diameter in an appropriate range, it is preferable to appropriately control the surface roughness of the porous magnetic core particle. Moreover, it is preferable that control of the speed of a ferritization reaction is easy, and control of the specific resistance and magnetic force of a porous magnetic core is easy. From these viewpoints, among the ferrites, Mn-based ferrites, Mn-Mg-based ferrites, Mn-Mg-Sr-based ferrites, and Li-Mn-based ferrites containing Mn are more preferable.
Below, the manufacturing process in the case of using a ferrite as porous magnetic carrier particles is demonstrated in detail.

<Step 1 (Weighing and mixing step)>
Weigh and mix the ferrite ingredients.
As a raw material of a ferrite, the metal particle of the said metal element, or its oxide, hydroxide, oxalate, carbonate etc. are mentioned, for example.
As an apparatus to mix, a ball mill, a planetary mill, a geot mill, a vibration mill etc. are mentioned, for example. Among these, a ball mill is preferable from the viewpoint of mixability.
For example, the weighed raw materials of ferrite and balls are placed in a ball mill, and ground and mixed over a period of 0.1 to 20.0 hours.

<Step 2 (temporary firing step)>
The raw material of the pulverized and mixed ferrite is temporarily fired in the air or in a nitrogen atmosphere at a firing temperature in the range of 700 ° C. to 1200 ° C. for 0.5 hours to 5.0 hours, Ferrite to obtain calcined ferrite. For the firing, for example, a firing furnace such as a burner firing furnace, a rotary firing furnace, or an electric furnace can be used.

<Step 3 (pulverization step)>
The calcined ferrite obtained in step 2 is crushed by a grinder.
As a grinder, a crusher, a hammer mill, a ball mill, a bead mill, a planetary mill, a geot mill etc. are mentioned, for example.
In order to obtain the desired particle size of the crushed ferrite product, for example, in the case of using a ball mill or bead mill, it is preferable to control the material of the balls or beads used, the particle size, and the grinding time. Specifically, in order to reduce the particle size of the calcined ferrite slurry, a ball with a high specific gravity may be used, or the grinding time may be lengthened. Further, in order to widen the particle size distribution of the calcined ferrite, balls and beads having a high specific gravity may be used to shorten the grinding time. Also, by mixing a plurality of calcined ferrites having different particle sizes, it is possible to obtain a calcined ferrite having a wide particle size distribution.
When a ball mill or bead mill is used, the wet process is more preferable than the dry process because the crushed product does not fly up in the mill and the grinding efficiency is high.

<Step 4 (granulation step)>
Water, a binder and, if necessary, a pore conditioner are added to the crushed product of calcined ferrite. As a pore regulator, a foaming agent, resin microparticles, etc. are mentioned, for example.
As a foaming agent, sodium hydrogencarbonate, potassium hydrogencarbonate, lithium hydrogencarbonate, ammonium hydrogencarbonate, sodium carbonate, potassium carbonate, lithium carbonate, ammonium carbonate etc. are mentioned, for example.
As resin fine particles, for example,
Polyester, polystyrene, styrene-vinyl toluene copolymer, styrene-vinyl naphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethacrylic acid methyl copolymer Styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene copolymer such as styrene-acrylonitrile-indene copolymer;
Polyvinyl chloride, phenolic resin, modified phenolic resin, maleic resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin; aliphatic polyhydric alcohol, aliphatic dicarboxylic acid, aromatic dicarboxylic acid, aromatic dialcohols and di-alcohols Polyester resin having as a structural unit a monomer selected from phenols; Fine particles such as polyurethane, polyamide, polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin, hybrid resin having a polyester unit and a vinyl polymer unit Can be mentioned.
Examples of the binder include polyvinyl alcohol.
In the step 3, in the case of wet grinding, it is preferable to add a binder and, if necessary, a pore adjusting agent, taking into consideration the water contained in the ferrite slurry.
The obtained ferrite slurry is dried and granulated using a spray dryer under a heating atmosphere of 100 ° C. or more and 200 ° C. or less to obtain a granulated product. As a spray dryer, a spray dryer is mentioned, for example.

<Step 5 (main firing step)>
The granulated product is fired in a temperature range of 800 ° C. or more and 1400 ° C. or less for 1 hour or more and 24 hours or less.
By raising the firing temperature and prolonging the firing time, firing of the porous magnetic core particles proceeds, and as a result, the pore diameter decreases and the number of pores decreases.

<Step 6 (sorting step)>
After crushing the particles obtained by firing as described above, if necessary, coarse particles or fine particles may be removed by classification or screening with a sieve.
The volume distribution standard 50% particle diameter (D50) of the magnetic core particles is preferably 18.0 μm or more and 68.0 μm or less from the viewpoint of suppression of carrier adhesion to the image and suppression of roughness of the image.

<Step 7 (filling step)>
The porous magnetic core particles may have low physical strength depending on the pore volume inside. From the viewpoint of enhancing the physical strength as the magnetic carrier, it is preferable to fill the resin in at least a part of the pores of the porous magnetic core particle. The amount of resin filled in the porous magnetic core particles is preferably 2 parts by mass or more and 15 parts by mass or less with respect to 100 parts by mass of the porous magnetic core particles. Only a part of the pores may be filled with the resin, or only the pores in the vicinity of the surface of the porous magnetic core particle may be filled with the resin, and voids may be left inside, or the pores may be completely May be filled with resin. However, it is preferable that the variation in the content of the resin for each magnetic carrier be small.
As a method for filling the pores of the porous magnetic core particles with a resin, for example, the resin solution is impregnated with the porous magnetic core particles by a coating method such as immersion method, spray method, brush coating method or fluidized bed, The method of volatilizing a solvent etc. are mentioned.

Moreover, as a method of filling resin in pores of porous magnetic core particles, there is also a method of diluting resin in a solvent and adding it to pores of porous magnetic core particles. The solvent used here may be any one that can dissolve the resin.
When a resin soluble in an organic solvent is used, examples of the organic solvent include toluene, xylene, cellosolve butyl acetate, methyl ethyl ketone, methyl isobutyl ketone and methanol. When a water-soluble resin or an emulsion-type resin is used, water can be used as a solvent.

The amount of solid resin content in the resin solution is preferably 1% by mass to 50% by mass, and more preferably 1% by mass to 30% by mass. If the amount of solid resin content is 50% by mass or less, the viscosity of the resin solution does not become too high, and the resin solution can be easily permeated uniformly into the pores of the porous magnetic core particles. Moreover, if the amount of resin solid content is 1 mass% or more, the fall of the adhesive force of resin to the porous magnetic core particle by the small amount of resin is suppressed.
Examples of the resin filled in the pores of the porous magnetic core particles include thermoplastic resins and thermosetting resins. It is preferable that the resin with which the pores are filled has a high affinity to the porous magnetic core particles, and when a resin having a high affinity is used, the resin to be used in the pores of the porous magnetic core particles is used. At the same time as filling, the surface of the porous magnetic core particles can also be covered with a resin.
As a resin to be filled, as a thermoplastic resin, for example, novolak resin, saturated alkyl polyester resin, polyarylate, polyamide resin, acrylic resin and the like can be mentioned. As a thermosetting resin, a phenol resin, an epoxy resin, unsaturated polyester resin, a silicone resin etc. are mentioned, for example.

The magnetic carrier used in the present invention is obtained by coating the surface of a magnetic carrier core with a resin to form a resin coating layer.
As a method of coating the surface of the magnetic carrier core with a resin, for example, a method of coating by a dipping method, a spray method, a brush method, a dry method, a coating method such as fluidized bed, and the like can be mentioned. Among these, the immersion method capable of appropriately exposing the magnetic carrier core to the surface is preferable.
The amount of the coating resin used for the resin coating layer is 0.1 parts by mass or more and 5.0 parts by mass with respect to 100 parts by mass of the magnetic carrier core, from the viewpoint of appropriately exposing the metal oxide portion of the magnetic carrier core to the surface. It is preferable that it is the following.

The methods for measuring various physical properties of toner, magnetic carrier and raw materials are described below.
<Molecular weight measurement of crystalline resin by GPC>
First, the crystalline resin is dissolved in o-dichlorobenzene at room temperature for 24 hours. Then, the resulting solution is filtered through a solvent-resistant membrane filter "Maechoridisc" (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is about 0.8% by mass. It measures on condition of the following using this sample solution.
Device: HLC-8121GPC / HT (made by Tosoh Corporation)
Column: TSKgel GMHHR-H HT 7.8 cmI. D × 30 cm 2 series (made by Tosoh Corporation)
Detector: RI for high temperature
Temperature: 135 ° C
Solvent: o-Dichlorobenzene (0.05% ionol added)
Flow rate: 1.0 ml / min
Sample: 0.1% of a sample is measured under the above conditions of 0.4 ml injection, and a molecular weight calibration curve prepared using a monodispersed polystyrene standard sample is used to calculate the molecular weight of the sample. Furthermore, it is calculated by performing polyethylene conversion with the conversion equation derived from the Mark-Houwink viscosity equation.

<Measurement of Molecular Weight of Amorphous Resin by GPC>
The molecular weight distribution of the THF soluble matter of the resin is measured by gel permeation chromatography (GPC) as follows.
First, the toner is dissolved in tetrahydrofuran (THF) for 24 hours at room temperature. Then, the resulting solution is filtered through a solvent-resistant membrane filter "Maechoridisc" (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is about 0.8% by mass. It measures on condition of the following using this sample solution.
Device: HLC8120 GPC (detector: RI) (made by Tosoh Corporation)
Column: Shodex KF-801, 802, 803, 804, 805, 806, 80
Seven of 7 series (made by Showa Denko)
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 ml / min
Oven temperature: 40.0 ° C
Sample injection volume: 0.10 ml
In calculating the molecular weight of the sample, standard polystyrene resin (for example, trade name "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) are used as molecular weight calibration curves.

<Method of measuring softening point of amorphous resin, resin composition, toner>
The measurement of the softening point of the resin is performed according to a manual attached to the apparatus, using a constant load extrusion type capillary rheometer "flow characteristic evaluation apparatus Flow Tester CFT-500D" (manufactured by Shimadzu Corporation). In this apparatus, while applying a constant load from the top of the measurement sample with a piston, the temperature of the measurement sample filled in the cylinder is raised and melted, and the melted measurement sample is extruded from the die at the bottom of the cylinder. It is possible to obtain a flow curve showing the relationship between temperature and temperature.
In the present invention, the "melting temperature in the 1/2 method" described in the manual attached to the "Flow Characteristic Evaluation Device Flow Tester CFT-500D" is taken as the softening point. The melting temperature in the 1⁄2 method is calculated as follows. First, a half of the difference between the amount of drop Smax of the piston at the end of the outflow and the amount Smin of drop of the piston at the start of the outflow is determined (this is taken as X. X = (Smax-Smin) / 2). The temperature at which the amount of descent of the piston in the flow curve is the sum of Smin and X is the melting temperature in the 1/2 method.
About 1.0 g of the resin is compression molded at about 10 MPa for about 60 seconds under an environment of 25 ° C. using a tablet molding compressor (for example, NT-100H, manufactured by NPA Systems Inc.), The cylindrical one having a diameter of about 8 mm is used.
The measurement conditions of CFT-500D are as follows.
Test mode: Heating method starting temperature: 50 ° C
Reaching temperature: 200 ° C
Measurement interval: 1.0 ° C
Heating rate: 4.0 ° C / min
Piston cross-sectional area: 1.000 cm ²
Test load (piston load): 10.0 kgf (0.9807 MPa)
Preheating time: 300 seconds Die hole diameter: 1.0 mm
Die length: 1.0 mm

<Measurement of Glass Transition Temperature (Tg) and Melting Peak Temperature (Tp) of Resin and Toner>
The glass transition temperature of the resin or toner is measured according to ASTM D3418-82 using a differential scanning calorimeter “Q2000” (manufactured by TA Instruments).
The temperature correction of the device detection unit uses the melting points of indium and zinc, and the heat of fusion uses the heat of fusion of indium.
Specifically, approximately 3 mg of resin or toner is precisely weighed, placed in an aluminum pan, and measured using an empty aluminum pan as a reference under the following conditions.
Heating rate: 10 ° C / min
Measurement start temperature: 30 ° C
Measurement end temperature: 180 ° C
The measurement is performed at a temperature rising rate of 10 ° C./min in a measurement range of 30 to 180 ° C. The temperature is once raised to 180 ° C. and held for 10 minutes, then the temperature is lowered to 30 ° C., and then the temperature is raised again. In the second temperature rising process, a specific heat change is obtained in the temperature range of 30 to 100 ° C. The intersection of the line at the midpoint of the baseline before and after the specific heat change at this time and the differential thermal curve is taken as the glass transition temperature (Tg) of the resin.
Further, the temperature at which the maximum endothermic peak of the temperature-endothermic curve in the temperature range of 60 to 90 ° C. is taken as the melting peak temperature (Tp).

<Measurement of endothermic peak derived from crystalline resin from toner by DSC>
The measurement of the endothermic peak derived from the crystalline resin from the toner is measured according to ASTM D3418-82 using a differential scanning calorimeter “Q2000” (manufactured by TA Instruments).
The temperature correction of the device detection unit uses the melting points of indium and zinc, and the heat of fusion uses the heat of fusion of indium.
Specifically, about 3 mg of the toner is precisely weighed, placed in an aluminum pan, and measured under the following conditions using an empty aluminum pan as a reference.
Heating rate: 10 ° C / min
Measurement start temperature: 30 ° C
Measurement end temperature: 180 ° C
Holding temperature: 50 ° C
The measurement is performed at a temperature rising rate of 10 ° C./min in a measurement range of 30 to 180 ° C. The temperature is once raised to 50 ° C. and maintained for 3 days, then the temperature is lowered to 30 ° C., and then the temperature is raised again. In the second temperature rising process, an endothermic peak is obtained with respect to the baseline in the temperature range of 30 to 100 ° C. When the endothermic peak at this time can be separated from the endothermic peak derived from enthalpy relaxation or a release agent, the endothermic peak is regarded as an endothermic peak derived from the crystalline resin.
Also, if the obtained endothermic peak can not be separated from the endothermic peak derived from enthalpy relaxation or a release agent, or if the compatibility between the amorphous resin and the crystalline resin is high and the endothermic peak does not appear, The crystalline resin is separated from the toner using the difference in solubility of
The separation of the crystalline resin from the toner is carried out according to the following procedure.
First separation: Toner is dissolved in methyl ethyl ketone (MEK) at 23 ° C., and soluble (amorphous resin) and insoluble (wax, wax dispersant, crystalline resin added if necessary, colorant, inorganic) Separate particles etc).
Second separation: Insoluble matter (wax, wax dispersant, optional added crystalline resin, colorant, inorganic particles, etc.) obtained in the first separation is dissolved in MEK at 100 ° C. (Crystalline resin, wax, wax dispersant) and insoluble matter (colorant, inorganic particles) are separated.
Third separation: The soluble matter (crystalline resin, wax, wax dispersant) obtained in the second separation is dissolved in chloroform at 23 ° C., and the soluble matter (crystalline resin) and the insoluble matter (wax, wax) Dispersant) is separated.
The endothermic peak derived from the crystalline resin can be measured by performing the DSC measurement of the obtained soluble matter (crystalline resin).

<Method of measuring weight average particle diameter (D4) of toner particles>
The weight average particle diameter (D4) of the toner particles is measured with a Coulter Counter Multisizer 3 (registered trademark, manufactured by Beckman Coulter, Inc.), a precise particle size distribution measuring device by a pore electrical resistance method equipped with an aperture tube of 100 μm. Measurement data is measured using 25,000 channels of effective measurement channels using the dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter Inc.) for condition setting and measurement data analysis. Analyze and calculate
As the electrolytic aqueous solution used for the measurement, a solution in which special grade sodium chloride is dissolved in ion exchange water so that the concentration is about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.
In addition, before performing measurement and analysis, the setting of the dedicated software is performed as follows.
Set the total count number in the control mode to 50000 particles, change the number of measurements to 1 on the "Change standard measurement method (SOM) screen" of the dedicated software, and set the Kd value to "standard particle 10.0 μm" (Beckman Coulter Set the value obtained using By pressing the threshold / noise level measurement button, the threshold and noise level are automatically set. Also, set the current to 1600 μA, the gain to 2, the electrolyte to ISOTON II, and check the flush of the aperture tube after measurement.
In the dedicated software “pulse to particle size conversion setting screen”, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm or more and 60 μm or less.

The specific measurement method is as follows.
(1) Place about 200 ml of the electrolytic aqueous solution in a 250 ml round bottom beaker made exclusively for Multisizer 3 and set it on a sample stand, and stir the stirrer rod counterclockwise at 24 revolutions / second. Then, dirt and air bubbles in the aperture tube are removed by the "flash of aperture tube" function of special software.
(2) About 30 ml of the above-mentioned electrolytic aqueous solution is placed in a 100 ml flat bottom beaker made of glass, and "contaminone N" (a nonionic surfactant, an anionic surfactant, an organic builder precisely measured in pH 7 as a dispersant) Add about 0.3 ml of a diluted solution obtained by diluting a 10% by weight aqueous solution of a neutral detergent for cell washing (manufactured by Wako Pure Chemical Industries, Ltd.) with ion-exchanged water three times by mass.
(3) Two oscillators with an oscillation frequency of 50 kHz are incorporated 180 degrees out of phase, and an electric output of 120 W is provided in a water tank of "Ultrasonic Dispersion System Tetora 150" (manufactured by Nikkaki Bios Co., Ltd.) A predetermined amount of ion exchange water is placed, and about 2 ml of the Contaminone N is added to the water tank.
(4) The beaker of said (2) is set to the beaker fixing hole of the said ultrasonic dispersion device, and an ultrasonic dispersion device is operated. Then, the height position of the beaker is adjusted so that the resonance state of the liquid surface of the electrolytic aqueous solution in the beaker is maximized.
(5) While the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of toner is added little by little to the electrolytic aqueous solution and dispersed. Then, ultrasonic dispersion processing is continued for another 60 seconds. In ultrasonic dispersion, the water temperature of the water tank is appropriately adjusted so as to be 10 ° C. or more and 40 ° C. or less.
(6) In the round bottom beaker of (1) placed in the sample stand, the electrolytic aqueous solution of (5) in which the toner is dispersed using a pipette is dropped to adjust the measurement concentration to about 5%. . Then, measurement is performed until the number of measurement particles reaches 50,000.
(7) The measurement data is analyzed by the dedicated software attached to the device to calculate the weight average particle diameter (D4). The "average diameter" on the analysis / volume statistical value (arithmetic mean) screen when the graph / volume% is set by dedicated software is the weight average particle size (D4).

<Method of measuring the average circularity of toner>
The average circularity of the toner is measured by a flow type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) under measurement and analysis conditions at the time of calibration.
The measurement principle of the flow type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) is to perform image analysis by imaging flowing particles as a still image. The sample added to the sample chamber is fed into the flat sheath flow cell by a sample suction syringe. The sample fed into the flat sheath flow is sandwiched by the sheath liquid to form a flat flow. The sample passing through the flat sheath flow cell is irradiated with strobe light at intervals of 1/60 seconds, and it is possible to capture flowing particles as a still image. Also, since the flow is flat, the image is captured in focus. The particle image is imaged by a CCD camera, and the imaged image is subjected to image processing with an image processing resolution of 512 × 512 pixels (0.37 × 0.37 μm per pixel), and the outline of each particle image is extracted, and the particle image The projected area S, the perimeter L, etc. of the
Next, the equivalent circle diameter and the degree of circularity are determined using the area S and the perimeter L. The equivalent circle diameter is the diameter of a circle having the same area as the projected area of the particle image, and the circularity C is a value obtained by dividing the perimeter of the circle determined from the equivalent circle diameter by the perimeter of the particle projection image It is defined as and calculated by the following equation.
Circularity C = 2 × (π × S) ^1/2 / L
When the particle image is circular, the degree of circularity is 1.000, and the degree of circularity becomes a smaller value as the degree of unevenness on the periphery of the particle image increases. After calculating the degree of circularity of each particle, the range of degree of circularity 0.200 to 1.000 is divided into 800, the arithmetic mean value of the obtained degree of circularity is calculated, and the value is defined as the average degree of circularity.
The specific measurement method is as follows. First, about 20 ml of ion exchanged water from which impure solids and the like have been removed in advance is placed in a glass container. Among them, “contaminone N” (nonionic surfactant, anionic surfactant, 10% by weight aqueous solution of neutral detergent for pH 7 precision measuring instrument cleaning consisting of organic builders as a dispersing agent, Wako Pure Chemical Industries, Ltd. Add about 0.2 ml of a diluted solution of about 3 times by volume diluted with deionized water. Further, about 0.02 g of a measurement sample is added, and dispersion treatment is performed for 2 minutes using an ultrasonic dispersion device to obtain a dispersion for measurement. At that time, the dispersion is suitably cooled so that the temperature of the dispersion becomes 10 ° C. or more and 40 ° C. or less. As the ultrasonic wave disperser, a table-top type ultrasonic cleaner disperser (for example, "VS-150" (manufactured by velvocrea)) having an oscillation frequency of 50 kHz and an electric output of 150 W is used. Ion exchange water is added, and about 2 ml of the contaminone N is added to the water tank.
For measurement, the flow type particle image analyzer equipped with a standard objective lens (10 ×) is used, and a particle sheath “PSE-900A” (manufactured by Sysmex Corporation) is used as a sheath liquid. The dispersion adjusted according to the procedure is introduced into the flow type particle image analyzer, and 3000 toner particles are measured in the total count mode in the HPF measurement mode. Then, by setting the binarization threshold value at the time of particle analysis to 85% and designating the particle diameter of the analysis particle, it is possible to calculate the percentage number of particles in that range (%) and the average circularity. The average degree of circularity of the toner is set to a circle equivalent diameter of 1.98 μm to 39.96 μm, and the average degree of circularity of the toner is determined.
In the measurement, automatic focusing is performed using standard latex particles (for example, “RESEARCH AND TEST PARTICLES Latex Microsphere Suspensions 5200A” manufactured by Duke Scientific Inc. diluted with ion exchange water) before the start of the measurement. After that, it is preferable to perform focusing every two hours from the start of measurement.
In the embodiment of the present invention, a flow type particle image analyzer which has been subjected to a calibration work by Sysmex and which has received a calibration certificate issued by Sysmex, is used. The measurement was performed under the measurement and analysis conditions when proof of calibration was received except that the particle size of the analysis particle was limited to the circle equivalent diameter of 1.98 μm or more and less than 39.69 μm.

<Method of measuring acid number>
The acid value is the mass (mg) of potassium hydroxide necessary to neutralize the acid contained in 1 g of the sample. That is, the mass [mg] of potassium hydroxide required to neutralize free fatty acids and resin acids contained in 1 g of sample is referred to as the acid value.
In the present invention, the acid value is measured according to JIS K 0070-1992. Specifically, it measures according to the following procedures.
(1) Preparation of Reagent 1.0 g of phenolphthalein is dissolved in 90 mL of ethyl alcohol (95% by volume), ion-exchanged water is added to make it 100 mL, and a phenolphthalein solution is obtained.
7 g of special grade potassium hydroxide is dissolved in 5 mL of water, and ethyl alcohol (95% by volume) is added to make 1 liter. Place in an alkali resistant container and leave it for 3 days so as not to touch carbon dioxide gas etc. After standing, it is filtered to obtain potassium hydroxide solution. The resulting potassium hydroxide solution is stored in an alkali resistant container. The factor of the potassium hydroxide solution is as follows: 25 mL of 0.1 mol / L hydrochloric acid is taken in an Erlenmeyer flask, several drops of the above-mentioned phenolphthalein solution are added, the above potassium hydroxide solution is required for neutralization by titration with the above potassium hydroxide solution Determine from the amount of solution. The 0.1 mol / L hydrochloric acid used is one prepared according to JIS K 8001-1998.
(2) Operation (A) This test 2.0 g of a sample is placed in a 200 mL Erlenmeyer flask and precisely weighed, 100 mL of a mixed solution of toluene / ethanol (2: 1) is added, and the sample is dissolved over 5 hours. Subsequently, several drops of the above-mentioned phenolphthalein solution are added as an indicator, and titration is performed using the above-mentioned potassium hydroxide solution. The end point of the titration is when the light pink of the indicator lasts for 30 seconds.
(B) Blank test The same titration as in the above operation is performed except that no sample is added (ie, only a mixed solution of toluene / ethanol (2: 1) is used).
(3) Calculation of acid value The obtained result is substituted into the following equation to calculate the acid value.
AV = [(B−A) × f × 5.61] / S
In the above formula, AV indicates the acid value [mg KOH / g], A indicates the addition amount [mL] of the potassium hydroxide solution in a blank test, and B indicates the addition amount [mL] of the potassium hydroxide solution in this test. Indicated, f indicates the factor of potassium hydroxide solution, and S indicates the mass [g] of the sample.

<Method of measuring volume average particle diameter (D50) of magnetic carrier and porous magnetic core>
In the present invention, the measurement of the particle size distribution was performed using a laser diffraction / scattering type particle size distribution measuring apparatus (trade name: Microtrac MT3300EX, manufactured by Nikkiso Co., Ltd.).
When measuring the volume average particle diameter (D50) of the magnetic carrier and porous magnetic core particles, a sample feeder for dry measurement (trade name: One shot dry sample conditioner Turbotrac, manufactured by Nikkiso Co., Ltd.) is attached. I did it. As a supply condition of Turbotrac, a dust collector was used as a vacuum source, the air volume was 33 L / sec, and the pressure was 17 kPa. Control was performed automatically on the software. As the particle size, a 50% particle size (D50), which is a cumulative value of volume average, was determined. Control and analysis were performed using attached software (version 10.3.3-202D). The measurement conditions are as follows.
Set Zero time: 10 seconds Measurement time: 10 seconds Number of measurements: 1 particle refractive index: 1.81%
Particle shape: non-spherical Upper limit of measurement: 1408 μm
Lower limit of measurement: 0.243 μm
Measurement environment: Temperature 23 ° C / humidity 50% RH

<Measurement of storage elastic modulus (G ′) and loss elastic modulus (G ′ ′) of resin coated layer>
As a measuring device of storage elastic modulus (G ') and loss elastic modulus (G "), a rotating plate type rheometer (trade name: ARES, manufactured by TA INSTRUMENTS) is used. The resin A and the coating resin B may be dissolved in toluene and mixed, and then the sample obtained by removing the solvent or the coating resin eluted from the magnetic carrier with toluene may be used.
A sample to be measured is a sample press-molded into a disc having a diameter of 7.9 mm and a thickness of 2.0 ± 0.3 (mm) using a tablet molding machine under an environment of a temperature of 25 ° C. The sample is mounted on a parallel plate and heated from room temperature (25 ° C.) to 180 ° C. over 20 minutes to adjust the shape of the sample and then cooled to 25 ° C., which is the measurement start temperature of viscoelasticity, Start. At this time, the sample is set so that the initial normal force becomes zero. Also, as described below, in the subsequent measurement, the automatic tension adjustment (Auto Tension Adjustment ON) can cancel the influence of the normal force. The measurement was performed under the following conditions.
(1) A parallel plate having a diameter of 7.9 mm was used.
(2) Frequency (Frequency): 1.0 Hz
(3) The applied strain initial value (Strain) was set to 0.1%.
(4) Measurement is performed at a temperature rising rate (Ramp Rate) of 2.0 [° C./min] in a temperature range of 25 ° C. or more and 120 ° C. or less. The measurement is performed under the following setting conditions of the automatic adjustment mode. Measure in the Auto Strain adjustment mode (Auto Strain).
(5) Set the maximum applied strain to 20.0%.
(6) Set the maximum torque (Max Allowed Torque) to 200.0 [g · cm], and set the minimum torque (Min Allowed Torque) to 0.2 [g · cm].
(7) Set the Strain Adjustment to 20.0% of the Current Strain. In measurement, an automatic tension adjustment mode (Auto Tension) is adopted.
(8) Set Auto Tension Direction to Compression.
(9) Set Initial Static Force to 100 g, and set Auto Tension Sensitivity to 40.0 g.
(10) The operating condition of the automatic tension (Auto Tension) is set to Sample Modulus: 1.0 × 10 ³ Pa or more.
Read the results of storage modulus (G ') and loss modulus (G ") in the range of 70 ° C to 100 ° C, and confirm the minimum value and its temperature.

<Measurement of Weight Average Molecular Weight (Mw) and Peak Molecular Weight (Mp) of Coating Resin A and Coating Resin B in Resin Coating Layer and Ratio of Their Contents>
The weight average molecular weight (Mw) and peak molecular weight (Mp) of the coating resin A and the coating resin B in the resin coating layer are measured by gel permeation chromatography (GPC) according to the following procedure.
First, a measurement sample is prepared as follows.
The sample (mixture of coating resin A and coating resin B separated from the coating resin separated from the magnetic carrier) and THF are mixed at a concentration of 5 mg / mL and allowed to stand at room temperature for 24 hours. Dissolve the sample in THF. Thereafter, a sample treated with a filter (trade name: Misho disc H-25-2, manufactured by Tosoh Corp., and trade name: Exclodisc 25 CR German Science Japan Ltd.) is subjected to a sample of GPC I assume.
Next, using a GPC measurement apparatus (trade name: HLC-8120GPC, manufactured by Tosoh Corporation), measurement is performed under the following measurement conditions according to the operation manual of the GPC measurement apparatus.
[Measurement condition]
Device: High-speed GPC (trade name: HLC 8120 GPC, manufactured by Tosoh Corporation)
Column: 7 columns of Shodex KF-801, 802, 803, 804, 805, 806, 807 (manufactured by Showa Denko KK)
Eluent: THF
Flow rate: 1.0 mL / min Oven temperature: 40.0 ° C.
Sample injection volume: 0.10 mL
In calculating the weight average molecular weight (Mw) and peak molecular weight (Mp) of the sample, the calibration curve is a standard polystyrene resin (manufactured by Tosoh Corp., 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) molecular weight calibration Use a curve.
The ratio of the content of the coating resin A and the content of the coating resin B is determined by the peak area ratio of the molecular weight distribution measurement. As shown in FIG. 2, when the regions 1 and 2 are completely separated, the ratio of the content of the resin A for coating and the resin B for coating is obtained from the area ratio of the respective regions. As shown in FIG. 3, when the respective regions overlap, division is made by a line dropped down from the inflection point of the GPC molecular weight distribution curve vertically to the horizontal axis, and from the area ratio of the regions 1 and 2 shown in FIG. The ratio of the content of A and the resin for coating B is determined.

<Separation of resin coating layer from magnetic carrier and separation of coating resin A and coating resin B in resin coating layer>
As a method of separating the resin coating layer from the magnetic carrier, a method of taking the magnetic carrier in a cup and eluting the coating resin using tetrahydrofuran (THF) can be mentioned.
The eluted resin can be separated using the following apparatus.
[Device configuration]
LC-908 (manufactured by Japan Analytical Industry Co., Ltd.)
JRS-86 (repeat injector, manufactured by Japan Analytical Industry Co., Ltd.)
JAR-2 (Autosampler, manufactured by Japan Analysis Industry Co., Ltd.)
FC-201 (Hula Cushion Collector, Gilson)
[Column configuration]
JAIGEL-1H to 5H (diameter 20 mm x 600 mm: preparative column, manufactured by Japan Analytical Industry Co., Ltd.)
[Measurement condition]
Temperature: 40 ° C
Solvent: Tetrahydrofuran (THF)
Flow rate: 5 mL / min Detector: RI
The elution time to become the peak molecular weight (Mp) of the coating resin A and the coating resin B is measured in advance by the following method, and the components of the coating resins A and B are separated before and after that. Thereafter, the solvent is removed and dried to obtain a coating resin A and a coating resin B. The composition of the coating resin is a Fourier transform infrared spectrometer (trade name: Spectrum One, Perkin)
The atomic group is identified from the absorption wave number using Elmer, and resin A for coating and resin B for coating are specified.

<Measurement of surface roughness Ra of magnetic carrier>
The surface roughness Ra of the magnetic carrier is measured using a non-contact three-dimensional surface measurement machine (Micromap 123 (manufactured by Ryoka System Co., Ltd.)). This measuring machine is a high precision laser microscope, and can three-dimensionalize the surface roughness in the plane being observed. Below, the specific example of a measuring method is shown.
A 20 × two-beam interference objective lens is attached to the optical microscope part of the micro map. A magnetic carrier is placed under the lens, and the interference image is vertically scanned using a CCD camera in Wave mode to obtain a three-dimensional image of the magnetic carrier surface. Surface roughness Ra of the cross section in a cutting plane is measured using the obtained analysis software (SX-Viewer Corporation Ryoka system company) attached to the above-mentioned measuring machine. The surface roughness Ra is obtained by summing the absolute values of the deviations from the average line to the cross-sectional curve in the evaluation length and averaging.
In order to eliminate the influence of curvature more with respect to the unevenness of the magnetic carrier, the measurement conditions are: cutting length 24 μm, evaluation length 8 μm, cutoff value 8 μm The center points of the lines are aligned to calculate the surface roughness Ra.
The surface roughness Ra is a value obtained as the arithmetic mean value of 50 magnetic carriers measured.

  Hereinafter, the present invention will be described based on examples, but the present invention is not limited thereto. In the following formulations, all parts are by mass unless otherwise noted.

<Production Example of Low Molecular Weight Amorphous Resin C>
Polyoxypropylene (2.2) -2, 2-bis (4-hydroxyphenyl) propane: 76.3 parts (0.19 mole; 100.0 mole% relative to the total number of moles of polyhydric alcohol)
·Terephthalic acid:
16.1 parts (0.10 mol; 60.0 mol% relative to the total number of moles of polyvalent carboxylic acid)
Succinic acid:
7.6 parts (0.06 mol; 40.0 mol% relative to the total number of moles of polyvalent carboxylic acid)
Titanium tetrabutoxide (esterification catalyst): 0.5 parts The above material was weighed in a reaction vessel equipped with a cooling pipe, a stirrer, a nitrogen introducing pipe, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was performed for 4 hours while stirring at a temperature of 200 ° C.
Further, the pressure in the reaction vessel was lowered to 8.3 kPa and maintained for 1 hour, then cooled to 160 and returned to atmospheric pressure (first reaction step).
-Tert-Butyl catechol (polymerization inhibitor): 0.1 part Then, the above material is added, the pressure in the reaction vessel is lowered to 8.3 kPa, and reaction is carried out for 1 hour while maintaining the temperature at 180 ° C. After confirming that the softening point measured according to 86 reached a temperature of 90 ° C., the temperature was lowered to stop the reaction (second reaction step), whereby a resin C was obtained. The obtained resin C had a peak molecular weight Mp 4500, a softening point Tm 90 ° C., and a glass transition temperature Tg 54 ° C.

<Production Example of High Molecular Weight Amorphous Resin D>
Polyoxypropylene (2.2) -2, 2-bis (4-hydroxyphenyl) propane: 73.8 parts (0.19 mole; 100.0 mole% relative to the total number of moles of polyhydric alcohol)
·Terephthalic acid:
12.5 parts (0.08 mol; 48.0 mol% relative to the total number of moles of polyvalent carboxylic acid)
・ Adipic acid:
7.8 parts (0.05 mol; 34.0 mol% relative to the total number of moles of polyvalent carboxylic acid)
Titanium tetrabutoxide (esterification catalyst): 0.5 parts The above material was weighed in a reaction vessel equipped with a cooling pipe, a stirrer, a nitrogen introducing pipe, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and reaction was performed for 2 hours while stirring at a temperature of 200 ° C.
Further, the pressure in the reaction vessel was lowered to 8.3 kPa and maintained for 1 hour, then cooled to 160 and returned to atmospheric pressure (first reaction step).
-Trimellitic acid:
5.9 parts (0.03 mol; 18.0 mol% relative to the total number of moles of polyvalent carboxylic acid)
-Tert-butyl catechol (polymerization inhibitor): 0.1 part Then, the above material is added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is conducted for 15 hours while maintaining the temperature at 200 ° C, ASTM D36- After confirming that the softening point measured according to 86 reached a temperature of 140 ° C., the temperature was lowered to stop the reaction (second reaction step) to obtain a resin D. The obtained resin D had a peak molecular weight Mp 10000, a softening point Tm 140 ° C., and a glass transition temperature Tg 60 ° C.

<Production Example of Crystalline Resin E>
-Hexanediol:
33.9 parts (0.29 mol; 100.0 mol% relative to the total number of moles of polyhydric alcohol)
・ Dodecanedioic acid:
66.1 parts (0.29 mol; 100.0 mol% relative to the total number of moles of polyvalent carboxylic acid)
The above materials were weighed into a reaction vessel equipped with a condenser, a stirrer, a nitrogen introduction pipe, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and reaction was performed for 3 hours while stirring at a temperature of 140 ° C.
-Tin 2-ethylhexanoate: 0.5 part Thereafter, the above material is added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the crystalline resin E is reacted by reacting for 4 hours while maintaining the temperature at 200 ° C. Obtained (first reaction step). The obtained crystalline resin E had a weight average molecular weight Mw of 10000 and a melting peak temperature Tp of 71 ° C.

<Production Example of Polymer F1 in which Styrene Acrylic Polymer is Graft-Polymerized to Polyolefin>
Low molecular weight polypropylene (Biscol 660P manufactured by Sanyo Chemical Industries, Ltd.):
10.0 parts (0.4 mol% with respect to the total number of moles of constituent monomers)
-Xylene: 25.0 parts The above material was weighed into a reaction vessel equipped with a condenser, a stirrer, a nitrogen introduction pipe, and a thermocouple. Next, the inside of the flask was replaced with nitrogen gas, and the temperature was gradually raised to a temperature of 175 ° C. while stirring.
·styrene:
68.0 parts (78.5 mol% relative to the total number of moles of constituent monomers)
-Acrylic acid cyclohexyl:
5.0 parts (3.9 mol% with respect to the total moles of constituent monomers)
・ Butyl acrylate:
12.0 parts (11.2 mol% relative to the total number of moles of constituent monomers)
・ Methacrylic acid:
5.0 parts (6.0 mol% with respect to the total number of moles of constituent monomers)
-Xylene: 10.0 parts-Di-t-butylperoxyhexahydroterephthalate: 0.5 parts Then, the above material was dropped over 3 hours, and the mixture was further stirred for 30 minutes. Then, the solvent was distilled off to obtain a polymer F1 in which a styrene acrylic polymer was graft-polymerized to polyolefin. The polymer F1 in which the styrene acrylic polymer was graft-polymerized to the obtained polyolefin had a peak molecular weight Mp 6000 and a softening point of 125 ° C.

<Production Example of Polymers F2 to F5 in which a styrene acrylic polymer is graft-polymerized to a polyolefin>
In the production example of the polymer F1 in which a styrene acrylic polymer is graft-polymerized to a polyolefin, the same operation is carried out except that the respective monomers and the number of parts by mass are changed as shown in Table 1, and the styrene acrylic polymer Polymers F2 to F5 undergoing graft polymerization were obtained. Physical properties are shown in Table 1.

<Toner 1 Production Example>
Amorphous resin C 60 parts Amorphous resin D 30 parts Crystalline resin E 10 parts Polymer F1 in which a styrene acrylic polymer is graft-polymerized to polyolefin
4 parts Fischer Tropsch wax (peak temperature of maximum endothermic peak 90 ° C)
4 parts C.I. I. Pigment Blue 15: 37 parts After mixing the above materials with a Henschel mixer (type FM-75, manufactured by Mitsui Mining Co., Ltd.) at a rotation speed of 20 s ⁻¹ for 5 minutes, the temperature was set to 130 ° C. The mixture was kneaded using a shaft kneader (PCM-30, manufactured by Ikegai Co., Ltd.). The obtained kneaded product was cooled and roughly crushed to 1 mm or less with a hammer mill to obtain a roughly crushed product. The obtained crushed material was finely pulverized by a mechanical pulverizer (T-250, manufactured by Turbo Kogyo Co., Ltd.). Furthermore, classification was performed using Faculty F-300 (manufactured by Hosokawa Micron Corporation) to obtain toner particles. The operating conditions were such that the classification rotor rotational speed was 130 s ⁻¹ and the dispersion rotor rotational speed was 120 s ⁻¹ .
The obtained toner particles were heat-treated by the surface treatment apparatus shown in FIG. 1 to obtain heat-treated toner particles. The operating conditions are as follows: feed amount = 5 kg / hr, hot air temperature = 160 ° C., hot air flow rate = 6 m ³ / min. Cold air temperature = −5 ° C. Cold air flow = 4 m ³ / min. , Blower air volume = 20 m ³ / min. , Injection air flow rate = 1 m ³ / min. And
To 100 parts of the heat-treated toner particles obtained, 1.0 part of hydrophobic silica (BET: 200 m ^{2 /} g) and 1.0 part of titanium oxide fine particles (BET: 80 m ^{2 /} g) surface-treated with isobutyltrimethoxysilane Toner 1 was obtained by mixing with a Henschel mixer (type FM-75, manufactured by Mitsui-Miike Kako Co., Ltd.) at a rotational speed of 30 s ⁻¹ for 10 minutes. The volume average particle diameter (D4) of Toner 1 was 6.5 μm, and the average circularity was 0.968. Physical properties of Toner 1 are shown in Table 2.

<Production Example of Toner 2 to 6>
In the production example of toner 1, polymer F1 in which a styrene acrylic polymer is graft-polymerized to polyolefin is changed to be as shown in Table 2, and the same operation is performed except that the process of the surface treatment apparatus is omitted. Toner 6 was obtained. Physical properties are shown in Table 2.

<Production Example of Magnetic Carrier Core 1>
Step 1 (Weighing and mixing step)
Fe ₂ O ₃ : 68.3% by mass
MnCO ₃ : 28.5 mass%
Mg (OH) ₂ : 2.0 mass%
SrCO ₃ : 1.2% by mass
The raw material of ferrite was weighed, and 20 parts of water was added to 80 parts of the raw material of ferrite, followed by grinding to prepare a slurry. The solid content concentration of the slurry was 80% by mass.
Step 2 (pre-baking step)
After the slurry is dried using a spray dryer (manufactured by Ohkawara Kakohki Co., Ltd.), firing is carried out at a temperature of 1050 ° C. for 3.0 hours in a nitrogen atmosphere (oxygen concentration: 1.0% by volume) in a batch electric furnace. And produced a calcined ferrite.
Step 3 (pulverization step)
After the calcined ferrite was crushed to about 0.5 mm with a crusher, water was added to prepare a slurry. The solid content concentration of the slurry was 70% by mass. This slurry was placed in a wet ball mill using 1/8 inch stainless steel beads, and subjected to a grinding treatment for 3 hours to obtain a slurry. Furthermore, this slurry is placed in a wet bead mill using zirconia of 1 mm in diameter, and subjected to grinding treatment for 4 hours, and a calcined ferrite slurry having a 50% particle diameter (D50) of 1.3 μm in volume basis of the calcined ferrite contained I got
Step 4 (granulation step)
After adding 1.0 part of ammonium polycarboxylate as a dispersant and 1.5 parts of polyvinyl alcohol as a binder to 100 parts of the above-mentioned calcined ferrite slurry, it is dried by a spray dryer (manufactured by Ogawara Kakoki Co., Ltd.) , Granulated into spherical particles. After adjusting the particle size of the obtained granulated product, it was heated at 700 ° C. for 2 hours using a rotary electric furnace to remove organic substances such as a dispersant and a binder.

Step 5 (baking step)
In a nitrogen atmosphere (oxygen concentration: 1.0% by volume), the time from room temperature (25 ° C.) to the firing temperature (1100 ° C.) was set to 2 hours, held at a temperature of 1100 ° C. for 4 hours, and fired. Thereafter, the temperature was lowered to 60 ° C. over 8 hours, the nitrogen atmosphere was returned to the atmosphere, and the temperature was removed at a temperature of 40 ° C. or less.
Step 6 (sorting step)
After the agglomerated particles are disintegrated, they are sieved with a sieve of 150 μm to remove coarse particles, air classification is performed to remove fine powder, and low magnetic components are further removed by magnetic separation to obtain a porous magnetic core. I got the particles. The obtained porous magnetic core particles were porous and had pores.
Step 7 (filling step)
100 parts of the obtained porous magnetic core particles are placed in a stirring vessel of a mixing stirrer (trade name: universal stirrer NDMV type, manufactured by Dalton Co., Ltd.), the temperature is maintained at 60 ° C., and the pressure is reduced to 2.3 kPa. While introducing nitrogen. To 50 parts of silicone resin (trade name: SR 2410, manufactured by Toray Dow Corning Co., Ltd.), 49.5 parts of toluene and 0.5 parts of γ-aminopropyltriethoxysilane are stirred for 10 minutes with a multi-blender mixer, The mixed resin solution was dropped onto the porous magnetic core particles. The dropping amount was adjusted to be 4.0 parts as solid content of the resin component with respect to 100 parts of the porous magnetic core particles.
After completion of the dropwise addition, stirring is continued for 2.5 hours as it is, the temperature is raised to 70 ° C., the solvent is removed under reduced pressure, and the particles of the porous magnetic core particles are filled with the resin composition obtained from the resin solution. did.
After cooling, the obtained resin-filled magnetic core particles were transferred to a container of a stirrer (mixer) (trade name: drum mixer UD-AT, manufactured by Sugiyama Heavy Industries, Ltd.) having a spiral blade. Thereafter, the temperature was raised to 220 ° C., which is the set temperature of the stirrer, at a temperature rising rate of 2 ° C./min under a nitrogen atmosphere. Stirring was carried out while heating at this temperature for 1.0 hour to cure the resin, and stirring was continued for an additional 1.0 hour while maintaining 200 ° C.
Then, it cooled to room temperature (25 degreeC), the ferrite particle with which hardened | cured resin was filled was taken out, and the nonmagnetic material was removed using the magnetic separator. Furthermore, coarse particles were removed by a vibrating screen to obtain a magnetic carrier core 1 filled with a resin. The 50% particle size (D50) based on the volume distribution of the magnetic carrier core 1 was 38.5 μm.

<Production Example of Magnetic Carrier Core 2>
To 100 parts of magnetite powder having a number average particle diameter of 0.30 μm, 4.0 parts of a silane coupling agent (3- (2-aminoethylamino) propyltrimethoxysilane) is added, and the temperature is 100 ° C. in a container. At high speed mixing and stirring, each fine particle was processed.
Phenol: 10 parts Formaldehyde solution (formaldehyde 40% by mass, methanol 10% by mass and water 50% by mass): 6 parts Treated magnetite: 84 parts The above material, 5 parts of 28% by mass ammonia water and 20 parts of water The mixture was stirred and heated to 85 ° C. for 30 minutes while mixing, and then held and polymerized for 3 hours to cure the synthesized phenolic resin. Thereafter, the cured phenolic resin was cooled to 30 ° C., water was further added, the supernatant was removed, and the precipitate was washed with water and then air dried. Next, this was dried at a temperature of 60 ° C. under reduced pressure (5 mmHg or less) to obtain a spherical magnetic carrier core 2 in a state in which the magnetic substance is dispersed. The 50% particle size (D50) based on the volume distribution of the magnetic carrier core 2 was 38.5 μm.

<Production Example of Magnetic Carriers 1 to 13>
Coating resin A and coating shown in Tables 3 and 4 in a planetary motion mixer (trade name: Nauta Mixer VN type, manufactured by Hosokawa Micron Ltd.) maintained at a temperature of 60 ° C. under reduced pressure (1.5 kPa) Resin B was added at a ratio shown in Table 5 and 900 parts of toluene was added to 100 parts of the resin components (coating resin A and coating resin B) and mixed until the resin was sufficiently dissolved, and the resin for coating The solution was prepared. Then, to 100 parts of the magnetic carrier core shown in Table 6, the resin solution for coating was charged so as to be 2.1 parts as a solid content of the resin component.
As a method of charging, first, a resin solution in an amount of 1/3 was charged, and a solvent removal and coating operation was performed for 20 minutes. Next, 1/3 of the amount of resin solution was added, solvent removal and coating operation were performed for 20 minutes, and further, 1/3 of amount of resin solution was added, and solvent removal and application operation was performed for 20 minutes.
Thereafter, a magnetic carrier coated with the composition of the resin for coating is mixed with a stirrer having a spiral blade in a rotatable mixing container (mixer) (trade name: Drum mixer UD-AT type, manufactured by Sugiyama Heavy Industries, Ltd.) Transferred to the container). The container was heat-treated at a temperature of 120 ° C. for 2 hours in a nitrogen atmosphere while being stirred at 10 revolutions per minute. The resulting magnetic carrier was separated from low magnetic force components by magnetic separation, passed through a sieve with an opening of 150 μm, and then classified with an air classifier. Magnetic carrier 1 having a 50% particle size (D50) of 39.0 μm on a volume distribution basis was obtained.
Magnetic carriers 2 to 13 were manufactured in the same manner as in the manufacture of the magnetic carrier 1 except that the type of the magnetic carrier core and the type and amount of the resin for coating were changed as shown in Table 6.
Each physical property value of the obtained magnetic carriers 1 to 13 is shown in Table 6.

<Production Example of Two-Component Developer 1>
Ten parts of Toner 1 was added to 90 parts of Magnetic Carrier 1, and shaken with a shaker (trade name: YS-8D: manufactured by Yayoi Co., Ltd.) to prepare 300 g of a two-component developer. . The conditions for shaking using a shaker were 200 rpm for 5 minutes.

<Production Example of Two-Component Developer 2 to 18>
The same procedure as in the production example of the two-component developer 1 was repeated except for changing as shown in Table 7, to obtain two-component developers 2 to 18.

Example 1
95 parts of toner 1 is added to 5 parts of magnetic carrier 1 and mixed for 5 minutes with a V-type mixer in a temperature 23 ° C./humidity 50% RH (normal temperature normal humidity) environment (hereinafter “N / N environment”) The developer for replenishment was obtained.
The following evaluation was performed using this two-component developer and the replenishment developer.
A modified full-color copying machine (trade name: imageRUNNER ADVANCE C9075 PRO) manufactured by Canon Inc. was used as the image forming apparatus.
A two-component developer was put in each color developing device, and a replenishment developer container containing the developer for each color replenishment was set, an image was formed, and various evaluations were carried out while conducting an endurance test.
The endurance test was carried out with the environment and the image ratio changed as follows, with a total of 150000 sheets of image output up to Step 1 and Step 2.
・ Step 1 (from 1st to 100000th)
Temperature 30 ° C / humidity 80% RH (hereinafter "H / H environment")
FFH output chart with 60% image ratio-Step 2 (from 100001 to 150000)
Temperature 23 ° C / humidity 5% RH (hereinafter "N / L environment")
FFH output chart with an image ratio of 3% Here, FFH is a value in which 256 gradations are displayed in hexadecimal, 00H is the first gradation of 256 gradations (white background), and FFH is 256 gradations. Of the 256th gradation (solid part) of
Other conditions are as follows.
Paper: Laser beam printer paper CS-814 (trade name) (81.4 g / m ² ) (Canon Marketing Japan Co., Ltd.)
Image formation speed: A4 size, full color, modified to output at 80 sheets / min.
Development conditions: The development contrast can be adjusted to an arbitrary value, and the automatic correction by the main body has been modified so as not to operate.
The peak-to-peak voltage (Vpp) of the alternating electric field was modified so that the frequency: 2.0 kHz, Vpp: 0.7 kV to 1.8 kV, in 0.1 kV steps.
Each color was modified to output an image in a single color.

Each evaluation item is shown below.
(1) Fog After outputting 100,000 sheets in Step 1, output 100 sheets of 00H output chart (A4 whole surface solid white image) with an image ratio of 100%, and measured the whiteness of the white background part by reflectometer (made by Tokyo Denshoku Co., Ltd.) . The fog density (%) was calculated from the difference between the whiteness and the whiteness of the transfer paper, and the highest fog density among 10 sheets was evaluated. Evaluation criteria are as follows.
A: less than 0.4% B: 0.4% or more and less than 0.8% C: 0.8% or more and less than 1.2% D: 1.2% or more and less than 1.6% E: 1.6% or more Less than 2.0% F: 2.0% or more The level at which the effect of the present invention was obtained was judged to be A to D.
The results are shown in Table 8.

(2) Image density difference before and after the endurance of each Step In Step 1 and Step 2, one FFH output chart (A4 whole surface solid image) having an image ratio of 100% was outputted at the beginning and the end of each Step. The image density was measured and judged with a spectrodensitometer 500 series (manufactured by X-Rite).
The measurement site is
5.0 cm, 15.0 cm, 25.0 cm from the left edge of the image (the first image formed side is the upper side) at a position 0.5 cm from the tip of the image (the one that was previously imaged) 3 points,
Three points of 5.0 cm, 15.0 cm and 25.0 cm from the left end of the image, at a position 7.0 cm from the front end of the image
Three points of 5.0 cm, 15.0 cm, 25.0 cm from the left end of the image, at a position of 14.0 cm from the front end of the image
An average value of 12 points was calculated with a total of 12 points of 3 points of 5.0 cm, 15.0 cm and 25.0 cm from the left end of the image at a position of 20.0 cm from the front end of the image.
Evaluation evaluated the difference of the first and last 12 point average value of each Step with the following reference | standard.
A: 0.00 or more and less than 0.04 B: 0.04 or more and less than 0.08 C: 0.08 or more and less than 0.12 D: 0.12 or more and less than 0.16 E: 0.16 or more and less than 0.20 F: 0.20 or more It was determined that the level at which the effects of the present invention were obtained was A to D.
The results are shown in Table 8.

(3) Image density difference between Step 1 and Step 2 One FFH output chart (A4 whole surface solid image) having an image ratio of 100% was outputted at the end of Step 1 and the end of Step 2. The output image measured reflection density like the said density difference, and calculated the average value of 12 points | pieces.
Evaluation evaluated the difference of the 12-point average value of Step1 and Step 2 on the following reference | standard.
A: 0.00 or more and less than 0.04 B: 0.04 or more and less than 0.08 C: 0.08 or more and less than 0.12 D: 0.12 or more and less than 0.16 E: 0.16 or more and less than 0.20 F: 0.20 or more It was determined that the level at which the effects of the present invention were obtained was A to D.
The results are shown in Table 8.

(4) White spots Output a chart in which halftone horizontal bands (30H width 10mm) and solid black horizontal bands (FFH width 10mm) are alternately arranged in the conveyance direction of the transfer sheet immediately after 200 continuous sheet feeding in STEP2. Do. The image is read by a scanner and binarization processing is performed. The luminance distribution (256 gradations) of a certain line in the conveyance direction of the binarized image was taken. Draw a tangent line to the luminance of the halftone at that time, and use the area of luminance that deviates from the tangent to the rear end of the halftone part (area: sum of the number of luminances) until it intersects with the solid part luminance, and let the whiteout degree be the following standard It was evaluated based on The evaluation was performed in cyan single color.
A: less than 20 B: 20 or more and less than 30 C: 30 or more and less than 40 D: 40 or more and less than 50 E: 50 or more The level at which the effect of the present invention was obtained was judged to be A to D.

(5) Comprehensive judgment The evaluation ranks of the above evaluation were quantified (A = 5, B = 4, C = 3, D = 2, E = 1, F = 0), and the total value was judged according to the following criteria. .
A: 21 or more and 25 or less B: 16 or more and 20 or less C: 10 or more and 15 or less D: 5 or more and 9 or less E: 4 or less The level at which the effect of the present invention was obtained was determined to be A to C.
The results are shown in Table 8.

Examples 2 to 13 and Comparative Examples 1 to 5
Evaluation was performed in the same manner as in Example 1 except that two-component developers 2 to 18 were used. The evaluation results are shown in Table 8.
In Example 2, the surface modification step is eliminated, the wax does not migrate to the vicinity of the toner surface, and the migration of the polymer in which the styrene acrylic polymer is graft-polymerized to the polyolefin is eliminated to the vicinity of the toner particle surface. Therefore, the hydrophobicity of the surface of the toner particles was reduced, and the evaluation in the HH environment and the white spots were slightly affected as compared with Example 1.
In Example 3, the minimum values of G ′ and G ′ ′ of visco-elastic properties from 70 ° C. to 100 ° C. are slightly low. The softening of the coating resin does not stabilize the surface of the resin coating layer, so In particular, the durability in the HH environment was somewhat affected, as compared with Example 2. Under the influence, the whiteout evaluation was also somewhat affected.
Example 4 results in that the minimum values of the visco-elastic properties G ′ and G ′ ′ from 70 ° C. to 100 ° C. are somewhat high. This is because the coating resin is hard and the coating film of the resin coating layer at the time of coating is As a result, the load on the toner during the endurance became large, and the result for the NL endurance was slightly affected.

Example 5 results in that the minimum value of G ′ and G ′ ′ of the visco-elastic characteristics from 70 ° C. to 100 ° C. is slightly lower than that of Example 3. According to the result, in the H / H environment In addition, the white spots were slightly affected, but the others were good results.
In Example 6, the acid value of the coating resin is high. As the acid value of the coating resin increased, the hygroscopic effect became stronger, and the evaluation of HH and environmental differences was somewhat affected.
In Example 7, the acid value of the coating resin is low. When the acid value of the coating resin is lowered, the coating film strength of the resin coating layer is affected, so the load on the toner when used for durability is increased, and the result for NL durability is observed.
In Example 8, the ratio of the coating resin A is low. As a result, the charge imparting ability to the toner tends to be reduced, and the evaluation in the H / H environment was observed.
In Example 9, the acid value of the coating resin is small. As a result, the surface (coated film surface) and strength of the resin coating layer become unstable, the load on the toner when used for durability increases, and the result of NL durability is affected.

In Example 10, the acid value of the coating resin is large. As a result, the effect of hygroscopicity became considerably strong, and the influence of HH was seen.
Since the amount of highly hydrophobic cyclohexyl methacrylate in the wax dispersant increases, the dispersibility of the wax decreases and the amount of the polymer in which the styrene acrylic polymer is graft-polymerized to the wax on the toner particle surface and the polyolefin is increased. Is reduced. As a result, the toner's hydrophobicity was lowered, and the evaluation in the HH environment and the subsequent white spots were affected.
In Example 12, the amount of highly hydrophobic cyclohexyl methacrylate in the wax dispersant was reduced, and the toner's hydrophobicity was reduced, so that the evaluation in the HH environment and the subsequent white spots were affected.
In Example 13, the chain length of cyclohexyl methacrylate in the wax dispersant was shortened, and the toner's hydrophobicity was reduced, so that the evaluation in the HH environment and the subsequent white spots were affected.

In Comparative Example 1, the coating film strength of the resin coating layer was not sufficiently obtained because the ratio of the coating resin A was too high, and the durability of the carrier was lowered, which affected all the evaluations. In particular, the evaluation level in the HH environment decreased.
In Comparative Example 2, when the ratio of the resin for coating A was too low, the surface (coating surface) of the resin coating layer became unstable and affected all evaluations. In particular, the evaluation level in the NL environment decreased.
The comparative example 3 is an example which does not use the (meth) acrylic acid ester monomer which has an alicyclic hydrocarbon group for resin for coating | cover. As a result, the surface (coating surface) of the resin coating layer becomes considerably unstable, and the evaluation level particularly in the H / H environment decreases.
Comparative Example 4 is an example in which the coating resin B is not used. This is because of the self-aggregation of the resin, and the smoothness of the surface (coating surface) of the resin coating layer and the coating strength of the resin coating layer can not be obtained, and all evaluations including white spots are obtained. The level has dropped.
In Comparative Example 5, the structure derived from the saturated alicyclic compound of the wax dispersant was lost, and the toner's hydrophobicity was greatly reduced, which greatly affected the durability in the HH environment and the subsequent evaluation.

  1. Raw material quantitative supply means, 2. Compressed gas flow rate adjusting means; Introductory pipe, 4. A projecting member, 5. Supply pipe, 6. Treatment room, 7. Hot air supply means, 8 (8-1, 8-2, 8-3). Cold air supply means, 9. Control means, 10. Collection means, 11. 12. hot air supply means outlet part; Distribution member, 13. 14. pivoting member, 14. Powder particle supply port

Claims (5)

A two-component developer containing toner and magnetic carrier,
The toner is a toner having toner particles comprising an amorphous resin, a wax and a wax dispersant,
The wax dispersant has a polymer in which a styrene acrylic polymer is graft-polymerized to a polyolefin,
The styrene acrylic polymer has a structure derived from a saturated alicyclic compound,
The magnetic carrier has a magnetic carrier core and a resin coating layer on the surface of the magnetic carrier core,
The surface roughness Ra of the magnetic carrier is 0.220 μm or less,
The resin coating layer contains a coating resin A and a coating resin B,
The coating resin A is a polymer of a monomer containing a (meth) acrylic acid ester monomer having an alicyclic hydrocarbon group,
The coating resin B is a polymer of a monomer containing a (meth) acrylic monomer having a polar group,
The content of the coating resin A in the resin coating layer is 10% by mass or more and 90% by mass or less based on the mass of the resin component in the resin coating layer,
A two-component developer characterized in that the content of the coating resin B in the resin coating layer is 10% by mass or more and 90% by mass or less based on the mass of the resin component in the resin coating layer. .   The two-component developer according to claim 1, wherein the acid value of the resin component in the resin coating layer is 1.0 mg KOH / g or more and 10.0 mg KOH / g or less. The minimum value of the storage elastic modulus (G ′) at 70 ° C. or more and 100 ° C. or less of the resin coating layer is 7.0 × 10 ⁷ Pa or more and 1.0 × 10 ⁹ Pa or less,
The minimum value of the loss elastic modulus (G ′ ′) of 70 ° C. or more and 100 ° C. or less of the resin coating layer is 1.0 × 10 ⁶ Pa or more and 1.0 × 10 ⁸ Pa or less. Two-component developer.   The structure derived from the saturated alicyclic compound is a monomer unit derived from at least one selected from the group consisting of cyclohexyl acrylate, cycloheptyl acrylate, cyclooctyl acrylate, cyclohexyl methacrylate, cycloheptyl methacrylate, and cyclooctyl methacrylate. The two-component developer as described in any one of 1 to 3.   The two-component developer according to any one of claims 1 to 4, wherein the wax is a hydrocarbon wax.

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