JP6714464B2 - toner - Google Patents

Description

The present invention relates to toner used in electrophotographic systems, electrostatic recording systems, electrostatic printing systems, and toner jet systems.

In recent years, electrophotographic full-color copying machines have become widespread, and their application to the printing market has begun. In the printing market, high speed, high image quality, and high productivity are required while supporting a wide range of media (paper types). For example, even if the paper type is changed from thick paper to thin paper, it is required to have constant velocity of the media so that printing can be continued without changing the process speed according to the paper type or changing the heating set temperature of the fixing device. There is. In order to deal with the constant velocity of media, it is required for the toner to properly complete fixing in a wide fixing temperature range from low temperature to high temperature.

In order to complete fixing at a wide range of fixable temperatures, a toner has been proposed in which a crystalline resin having a sharp melt property is added to the toner to improve low-temperature fixing performance (Patent Document 1).
Further, a toner has been proposed in which a low molecular weight organic compound is added as a plasticizer to improve low-temperature fixability (Patent Document 2).

A toner to which a cholesteric liquid crystal material is added as a low molecular weight organic compound has also been proposed (Patent Document 3). By using a cholesteric liquid crystal material that exhibits an interference color according to the heating temperature in the liquid crystal state as a coloring material, it can be colored in any color depending on the heating temperature, and a high-definition multi-color that is colored in a desired color locally There are those aiming to form a multicolor image such as a color image or a full color image.

JP, 2011-123352, A JP, 2006-330392, A JP 2002-372807 A

However, in the technique described in Patent Document 1, low-temperature fixability is improved, but if left in a high-temperature and high-humidity environment for a long period of time, the charge amount may decrease and toner scattering may occur. Further, when exposed to a high temperature environment, recrystallization of the crystalline polyester may proceed, the physical properties of the toner may change, and the low temperature fixability may decrease.
Further, in the technique described in Patent Document 2, a low-molecular weight organic compound may bleed along with the micro-Brownian motion of the resin, and the fixability may be impaired. Further, the compound bleeding out after long-term use may contaminate the magnetic carrier or the charging member, which may reduce the amount of charge or the image storability.

Further, in the technique described in Patent Document 3, the low temperature fixability is not improved and the image storability is not improved.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a toner having excellent low-temperature fixability, blocking resistance, image storability, and charge stability over long-term use.

According to one aspect of the present invention, there is provided a toner having toner particles containing a binder resin, a colorant, a polymer having a styrene acrylic polymer part and a polyolefin part, and cholesterol or a cholesterol derivative.

According to the present invention, it is possible to obtain a toner that is excellent in low-temperature fixability, blocking resistance, and image storability and that is electrostatically stable even after long-term use.

It is a schematic diagram of a thermal spheronization processing apparatus applicable to the production of the toner of the present invention.

The toner of the present invention is characterized by having toner particles containing a binder resin, a colorant, a polymer having a styrene-acrylic polymer portion and a polyolefin portion, and cholesterol or a cholesterol derivative. By using the toner particles as described above, it is possible to obtain a toner which is excellent in low-temperature fixing property, blocking resistance and image storability and which is stable in terms of charge even after long-term use.

In the present invention, it is important that cholesterol or a cholesterol derivative is used as toner particles together with a polymer having a styrene acrylic polymer part and a polyolefin part. It was confirmed that the low-temperature fixability of the toner is improved by using cholesterol or a cholesterol derivative in combination with the polymer. From this, it is considered that cholesterol or cholesterol derivative was finely dispersed and plasticizing the binder resin when used in combination with the polymer.

That is, it is assumed that the polymer functions as a dispersant for cholesterol or a cholesterol derivative or a compatibilizing aid. When the polymer is not used in combination, the low temperature fixability is not significantly different from that of the toner to which neither cholesterol or cholesterol derivative nor polymer was added, or the toner to which only cholesterol or cholesterol derivative was added. Then, the low-temperature fixability of the toner is almost determined by the fixing performance of the binder resin.

The reason why the polymer can function as a dispersant is considered to be related to the fact that the polymer has a polarity intermediate between that of the binder resin and cholesterol or the cholesterol derivative. It is also considered to have a relationship with the structure of a polymer composed of a polyolefin part having low polarity and a styrene-acrylic polymer part. It is presumed that the polymer behaves like a surfactant when the polyolefin moiety of the polymer is oriented to cholesterol or a cholesterol derivative and the styrene acrylic polymer moiety of the polymer faces the binder resin side.

That is, it is considered that the cholesterol or cholesterol derivative of the present invention having low polarity is finely dispersed in the binder resin to improve the compatibility and develop the plasticizing effect. Further, in a toner containing a low molecular weight organic compound, when repeatedly exposed to a high temperature environment, the low molecular weight organic compound may bleed and deposit on the surface of the toner or the surface of a fixed image. The cholesterol or cholesterol derivative used in the present invention may also have a bad effect due to bleeding depending on the conditions in that it is a low molecular weight organic compound.

However, in the present invention, it was also found that bleeding of cholesterol or a cholesterol derivative can be suppressed by using cholesterol or a cholesterol derivative together with the polymer. That is, it is considered that the polymer not only functions as a dispersant but also exhibits an anchor effect of suppressing the bleeding of the cholesterol or cholesterol derivative of the present invention. Since the polymer is a high molecular weight polymer having a polyolefin moiety and a styrene acrylic polymer moiety, it can be said that it is a material that is difficult to bleed originally.

On the other hand, the cholesterol or cholesterol derivative of the present invention is a low molecular weight organic compound and can be said to be a material that easily bleeds. When the cholesterol or the cholesterol derivative of the present invention and the polymer are used together, it is assumed that they are arranged in the vicinity of the polyolefin moiety of the polymer due to the polar relationship and are in an apparently high molecular weight state. There is. In other words, it is considered that the apparent increase in the molecular weight causes the cholesterol or the cholesterol derivative to be trapped in the polyolefin site, and the bleeding is suppressed.

The cholesterol or cholesterol derivative in the present invention is produced by a method for producing an ordinary ester from carboxylic acid or its derivative and cholesterol. The carboxylic acid and cholesterol can be reacted as they are for esterification, or one of them can be converted into a derivative having higher reactivity and then esterified. Alternatively, it can be produced by using a commercially available compound as the cholesteric liquid crystal material.

The cholesterol or cholesterol derivative of the present invention is preferably a derivative whose endothermic peak (melting point) is observed in differential scanning calorimetry (DSC). The endothermic peak (melting point) is preferably in the range of 80° C. or higher and 130° C. or lower from the viewpoint that the low temperature fixability can be improved by the combined use with the polymer. Further, it is more preferable that the cholesterol or the cholesterol derivative is a fatty acid cholesteryl ester compound in which a fatty acid and cholesterol are condensed, from the viewpoints of bringing the polarities of the polymer close to each other, accelerating the orientation to the polyolefin moiety, and excellent in bleeding suppression.

The polymer used in the present invention is a polymer having a polyolefin moiety and a styrene acrylic polymer moiety. The polyolefin portion of the polymer has a polarity close to that of cholesterol or a cholesterol derivative, and the styrene acrylic polymer portion has a polarity close to that of the binder resin. That is, the polymer used in the present invention can be present at the interface between the cholesterol or the cholesterol derivative and the binder resin due to the polymerization of the polyolefin and the styrene acrylic polymer. That is, the polymer behaves like a surfactant between the cholesterol or the cholesterol derivative and the binder resin so that the cholesterol or the cholesterol derivative can be finely dispersed or compatible with each other in the toner particles.

Further, the styrene acrylic polymer included in the polymer preferably has a unit derived from a saturated alicyclic compound. In particular, it is more preferable to have a unit such as bulky cycloalkyl acrylate or cycloalkyl methacrylate. Due to the high hydrophobicity of the bulky cycloalkyl acrylate unit and cycloalkyl methacrylate unit, the hydrophobicity of the toner particle surface is increased, and the amount of adsorbed water can be suppressed. Can be avoided.

The content of the cholesterol or the cholesterol derivative is preferably 1.0 part by mass or more and 30.0 parts by mass or less with respect to 100.0 parts by mass of the binder resin because the low temperature fixability can be improved. ..
Further, when the content of the polymer having the styrene acrylic polymer part and the polyolefin part is Dw [mass%], and the content of the cholesterol or the cholesterol derivative is Cw [mass%],
When the ratio of Dw and Cw (Dw/Cw) is 0.5 or more and 2.0 or less, it is possible to uniformly disperse or compatibilize the cholesterol derivative, improve low temperature fixing property, and suppress bleeding. It is preferable because it is possible.

The polyolefin in the polymer is preferably 80°C or higher and 140°C or lower, and more preferably 90°C or higher and 120°C or lower.
The content ratio of the polyolefin in the polymer is preferably 1% by mass or more and 30% by mass or less, and more preferably 3% by mass or more and 20% by mass or less with respect to the total amount of the styrene acrylic resin.

In the present invention, the method of polymerizing the styrene acrylic polymer and the polyolefin is not particularly limited, and a conventionally known method can be used.
For example, the wax dispersant of the present invention is a polymer in which a polyolefin and a styrene acrylic polymer are polymerized, and the styrene acrylic polymer has a unit derived from cycloalkyl acrylate or cycloalkyl methacrylate. The styrene acrylic polymer can be represented by an embodiment having a monomer unit represented by the following formula (1).

［前記式（１）中、Ｒ^１は水素原子又はメチル基を表し、Ｒ^２は飽和脂環式基を表す。］

[In the formula (1), R ¹ represents a hydrogen atom or a methyl group, and R ² represents a saturated alicyclic group. ]

R ² is preferably a saturated alicyclic hydrocarbon group, more preferably a saturated alicyclic hydrocarbon group having 3 to 18 carbon atoms, and further preferably a saturated alicyclic hydrocarbon group having 4 to 12 carbon atoms. Is. The saturated alicyclic hydrocarbon group includes a cycloalkyl group, a condensed polycyclic hydrocarbon group, a bridged ring hydrocarbon group, a spiro hydrocarbon group and the like.

Examples of such a saturated alicyclic group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a t-butylcyclohexyl group, a cycloheptyl group, a cyclooctyl group, a tricyclodecanyl group and a decahydro-2-naphthyl group. , Tricyclo[5.2.1.0 ^2,6 ]decan-8-yl group, pentacyclopentadecanyl group, isobornyl group, adamantyl group, dicyclopentanyl group, tricyclopentanyl group and the like. it can.

Further, the saturated alicyclic group may have an alkyl group, a halogen atom, a carboxy group, a carbonyl group, a hydroxy group or the like as a substituent. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms.
Among these saturated alicyclic groups, a cycloalkyl group, a condensed polycyclic hydrocarbon group, and a bridged ring hydrocarbon group are preferable, and a cycloalkyl group having 3 to 18 carbon atoms and a substituted or unsubstituted dicyclopentanyl group. A group and a substituted or unsubstituted tricyclopentanyl group are more preferable. Further, a cycloalkyl group having 4 to 12 carbon atoms is preferable, and a cycloalkyl group having 6 to 10 carbon atoms is particularly preferable.

The position and number of the substituents are arbitrary, and when two or more substituents are included, the substituents may be the same or different.
In the present invention, the content ratio of the monomer unit represented by the formula (1) is preferably 1 mol% or more and 40 mol% or less, and 3 mol% or more and 20 mol% or less, based on all the monomer units constituting the styrene acrylic polymer. % Or less is more preferable.

In addition, cyclohexyl methacrylate is preferred as the unit derived from the cycloalkyl acrylate and the unit derived from cycloalkyl methacrylate of the dispersant of the present invention, from the viewpoint of excellent hydrophobicity. By using cyclohexyl methacrylate, the hydrophobicity of the wax dispersant can be improved and the amount of water adsorbed by the dispersant can be reduced. As a result, it is considered that the amount of water adsorbed in a high temperature and high humidity environment can be reduced and the charging characteristics are improved.

Further, as the binder resin used in the toner of the present invention, a saturated polyester resin of an amorphous polyester resin, an unsaturated polyester resin, or both can be appropriately selected and used.
The binder resin used in the present invention may be an ordinary one composed of an alcohol component and an acid component, and both components will be exemplified below.

As the alcohol component, ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexane. Diol, neopentyl glycol, 2-ethyl-1,3-hexanediol, cyclohexanedimethanol, butenediol, octenediol, cyclohexenedimethanol, hydrogenated bisphenol A, bisphenol derivative represented by the following formula (1-1), Examples include hydrogenated products of the following formula (1-1) and diols represented by the following formula (1-2).

［式中、Ｒはエチレン基またはプロピレン基であり、ｘ及びｙはそれぞれ１以上の整数であり、かつｘ＋ｙの平均値は２から１０である。］

[In the formula, R is an ethylene group or a propylene group, x and y are each an integer of 1 or more, and the average value of x+y is 2 to 10. ]

On the other hand, examples of the divalent carboxylic acid that constitutes the binder resin include the following. Benzenedicarboxylic acid or its anhydride such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride; alkyldicarboxylic acid or its anhydride such as succinic acid, adipic acid, sebacic acid, azelaic acid. Further, succinic acid or an anhydride thereof substituted with an alkyl group or an alkenyl group having 6 to 18 carbon atoms; an unsaturated dicarboxylic acid such as fumaric acid, maleic acid, citraconic acid, itaconic acid or an anhydride thereof, etc. may be mentioned. ..

Further, examples of the alcohol component include polyhydric alcohols such as glycerin, pentaerythritol, sorbit, sorbitan, and oxyalkylene ether of novolac type phenol resin. Examples of the acid component include polyvalent carboxylic acids such as trimellitic acid, pyromellitic acid, 1,2,3,4-butanetetracarboxylic acid, benzophenonetetracarboxylic acid and anhydrides thereof.

The above-mentioned binder resin may be used with any catalyst such as a commonly used catalyst, for example, metals such as tin, titanium, antimony, manganese, nickel, zinc, lead, iron, magnesium, calcium, germanium; and these metal-containing compounds. Can also be manufactured. Among these catalysts, an amorphous polyester resin polycondensed using a titanium-based catalyst is particularly preferable. The binder resin polycondensed using the titanium-based catalyst is likely to be a homogeneous polyester resin, so that there is less variation among toner particles.

From the viewpoint of charging stability, the binder resin preferably has an acid value of 1 mgKOH/g or more and 30 mgKOH/g or less. When the amount is 30 mgKOH/g or less, the chargeability of the toner is easily stabilized, so that the developing efficiency is easily improved especially in a high temperature and high humidity environment.
Further, in the present invention, the toner can be plasticized at the time of fixing by containing the above-mentioned amorphous polyester resin and crystalline polyester resin as the binder resin. It is preferable that the binder resin contains an amorphous polyester resin and a crystalline polyester resin, because fixing can be performed at a lower temperature and fixing performance can be improved.

As the crystalline polyester resin that can be used in the present invention, a polycondensation of 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 main components is polycondensed. Obtained by reacting.
The aliphatic diol having 2 to 22 carbon atoms (more preferably 6 to 12 carbon atoms) is not particularly limited, but is preferably a chain (more preferably linear) aliphatic diol, and for example, , The following are listed. Ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, dipropylene glycol, 1,4-butanediol, 1,4-butadiene glycol, trimethylene glycol, tetramethylene glycol, penta Methylene glycol, hexamethylene glycol, octamethylene glycol, nonamethylene glycol, decamethylene glycol, neopentyl glycol. Among these, particularly preferred are straight chain aliphatics such as ethylene glycol, diethylene glycol, 1,4-butanediol, and 1,6-hexanediol, and α,ω-diols.

<Wax>
Examples of the hydrocarbon wax used in the toner of the present invention include the following. Low molecular weight alkylene polymer obtained by radical polymerization of alkylene under high pressure or by Ziegler catalyst or metallocene catalyst under low pressure; alkylene polymer obtained by thermal decomposition of high molecular weight alkylene polymer; from synthesis gas containing carbon monoxide and hydrogen A synthetic hydrocarbon wax obtained from a distillation residue of a hydrocarbon obtained by the Arge process or by hydrogenating these. Further, the one in which the hydrocarbon wax is fractionated by the use of press sweating method, solvent method, vacuum distillation or fractional crystallization method is more preferably used. Hydrocarbons as a base are those synthesized by the reaction of carbon monoxide and hydrogen using a metal oxide catalyst (often two or more multi-component catalysts) [eg, gintol method, hydrocoal method (fluid catalyst bed Hydrocarbon compounds synthesized by the use]; hydrocarbons having up to about several hundred carbon atoms obtained by the Arge method (using an identification catalyst bed), in which a large amount of waxy hydrocarbons can be obtained; alkylenes such as ethylene by a Ziegler catalyst The polymerized hydrocarbon is preferable because it is a straight chain hydrocarbon having little branching, small size, and long saturation.

A wax synthesized by a method not depending on the polymerization of alkylene is particularly preferable from the viewpoint of its molecular weight distribution. Paraffin wax is also preferably used. Hydrocarbon waxes such as paraffin wax and Fischer-Tropsch wax are preferable from the viewpoint of improving low-temperature fixability and hot offset resistance.
In the present invention, the wax is preferably used in an amount of 1 part by mass or more and 20 parts by mass or less per 100 parts by mass of the binder resin.
Further, in the endothermic curve at the time of temperature rise measured by a differential scanning calorimetry (DSC) device, the peak temperature of the maximum endothermic peak of the wax is preferably 45°C or higher and 140°C or lower. When the peak temperature of the maximum endothermic peak of the wax is within the above range, both blocking resistance and hot offset resistance of the toner can be achieved, which is preferable.

<Colorant>
Examples of the colorant that can be contained in the toner include the following.
Examples of the black colorant include carbon black; those obtained by toning black with a yellow colorant, a magenta colorant and a cyan colorant. As the colorant, a pigment may be used alone, but it is more preferable to use a dye and a pigment together to improve the sharpness from the viewpoint of the image quality of a full-color image.

Examples of the magenta toner pigment include the following. C. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48:2, 48:3, 48:4, 49, 50, 51, 52, 53, 54, 55, 57:1, 58, 60, 63, 64, 68, 81:1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 146, 147, 150, 163, 184, 202, 206, 207, 209, 238, 269, 282; I. Pigment Violet 19; C.I. I. Butt 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; C.I. I. Disperse Red 9; C.I. I. Solvent Violet 8, 13, 14, 21, 27; C.I. I. Oil-soluble dyes such as Disper 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; C.I. I. Basic dyes such as Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28.

Examples of the cyan toner pigment 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 having 1 to 5 phthalimidomethyl groups substituted on the phthalocyanine skeleton.
Examples of dyes for cyan toner include C.I. I. There is Solvent Blue 70.

Examples of the yellow toner pigment 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.
Examples of dyes for yellow toner include C.I. I. There is Solvent Yellow 162.
The amount of the colorant used is preferably 0.1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the binder resin.

<Charge control agent>
The toner may contain a charge control agent, if necessary. As the charge control agent contained in the toner, known charge control agents can be used, but in particular, a metal compound of an aromatic carboxylic acid which is colorless and has a high charging speed of the toner and which can stably maintain a constant charge amount is preferable.
Examples of the negative charge control agent include the following. Salicylic acid metal compound, naphthoic acid metal compound, dicarboxylic acid metal compound, polymer type compound having sulfonic acid or carboxylic acid in the side chain, polymer type compound having sulfonate or sulfonate ester side chain, carboxylate Alternatively, a polymer type compound having a carboxylic acid ester compound as a side chain, a boron compound, a urea compound, a silicon compound, a calixarene.
Examples of the positive charge control agent include a quaternary ammonium salt, a polymer type compound having the quaternary ammonium salt in its side chain, a guanidine compound, and an imidazole compound.
The charge control agent may be added internally or externally to the toner particles. The addition amount of the charge control agent is preferably 0.2 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the binder resin.

<Inorganic fine particles>
The toner of the present invention may contain inorganic fine particles, if necessary. The inorganic fine particles may be internally added to the toner particles or may be mixed with the toner particles as an external additive. As the external additive, inorganic fine powder such as silica, titanium oxide or aluminum oxide is preferable. 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, 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 for improving fluidity, and a specific surface area of 10 m ² for stabilizing durability is preferable. /G or more and 50 m< ² >/g or less of inorganic fine powder is preferable. In order to achieve both improvement of fluidity and stabilization of durability, an inorganic fine powder having a specific surface area of 50 m ² /g or more and 400 m ² /g and a specific surface area of 10 m ² /g or more and 50 m ² /g or less are used. You may use together with an inorganic fine powder.
The external additive is preferably used in an amount of 0.1 part by mass or more and 10.0 parts by mass or less based on 100 parts by mass of the toner particles. For mixing the toner particles and the external additive, a known mixer such as a Henschel mixer can be used.

<Developer>
The toner of the present invention can be used as a one-component developer, but in order to further improve dot reproducibility and obtain a stable image for a long period of time, a two-component developer is mixed with a magnetic carrier. It is preferable to use as.
As the magnetic carrier, for example, the following can be used. Iron powder whose surface is oxidized, or unoxidized iron powder, metal particles such as iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, chromium, and rare earths, alloy particles thereof, oxide particles A magnetic substance-dispersed resin carrier (so-called resin carrier) containing a magnetic substance such as ferrite, a magnetic substance, and a binder resin that holds the magnetic substance in a dispersed state.
When the toner of the present invention is mixed with a magnetic carrier to be used as a two-component developer, the carrier mixing ratio in that case is 2% by mass or more and 15% by mass or less, preferably the toner concentration in the two-component developer. When 4% by mass or more and 13% by mass or less, good results are usually obtained.

<Manufacturing method>
Next, the procedure for producing the toner of the present invention by the pulverization method will be described.
In the raw material mixing step, a binder resin, a colorant, a hydrocarbon wax, a wax dispersant, and cholesterol or a cholesterol derivative are weighed in predetermined amounts and mixed as materials for forming the toner particles. Examples of the mixing device are a double mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, a Nauta mixer, and a mechano hybrid (manufactured by Mitsui Mining Co., Ltd.).

Next, the mixed materials are melt-kneaded to disperse the colorant and the like in the binder resin. In the melt-kneading process, a batch kneader such as a pressure kneader or a Banbury mixer, or a continuous kneader can be used, and a single-screw or twin-screw extruder is mainly used because of its superiority in continuous production. ing. For example, a KTK type twin screw extruder (manufactured by Kobe Steel, Ltd.), a TEM type twin screw extruder (manufactured by Toshiba Machine Co., Ltd.), a PCM kneader (manufactured by Ikegai Corp.), a twin screw extruder (Kai) -CK company), Co-kneader (Bus company), Needex (Mitsui Mining Co., Ltd.).
Furthermore, the colored resin composition obtained by melt-kneading may be rolled with a two-roll mill or the like and cooled with water or the like in the cooling step.

Then, the cooled kneaded product is crushed to a desired particle size in a crushing step. In the crushing process, for example, after roughly crushing with a crusher such as a crusher, a hammer mill, and a feather mill, further, for example, a Kryptron system (manufactured by Kawasaki Heavy Industries, Ltd.), a super rotor (manufactured by Nisshin Engineering Co., Ltd.) Finely pulverized with a turbo mill (made by Freund Turbo Co., Ltd.) or an air jet type fine pulverizer.

Then, if necessary, an inertial classification method elbow jet (manufactured by Nittetsu Mining Co., Ltd.), a centrifugal force classification method turboplex (manufactured by Hosokawa Micron Corporation), TSP separator (manufactured by Hosokawa Micron Corporation), faculty (Hosokawa Micron Corporation) The toner particles are obtained by classification using a classifier such as the one manufactured by Co., Ltd. or a sieving machine.
Further, if necessary, after pulverization, a hybridization system (manufactured by Nara Machinery Co., Ltd.) or a mechanofusion system (manufactured by Hosokawa Micron Co., Ltd.) and surface modification treatment of toner particles such as heat treatment are performed. You can also In the heat treatment step of the present invention, it is more preferable to use hot air from the viewpoint of excellent cohesion and shape uniformity of the toner particles in the heat treatment step.

Hereinafter, a method of performing heat treatment on resin particles using the heat treatment apparatus shown in FIG. 1 will be specifically exemplified.
The resin particles quantitatively supplied by the raw material quantitative supply means 1 are guided by the compressed gas adjusted by the compressed gas flow rate adjusting means 2 to the introduction pipe 3 installed on the vertical line of the raw material supply means. The mixture that has passed through the introduction pipe 3 is uniformly dispersed by the conical projection member 4 provided in the central portion of the raw material supply means, and is guided to the radially extending eight-direction supply pipes 5 where heat treatment is performed. Guided to 6.

At this time, the flow of the resin particles supplied to the processing chamber 6 is regulated by the regulation unit 9 provided in the processing chamber 6 for regulating the flow of the resin particles. Therefore, the resin particles supplied to the processing chamber 6 are heat-treated while swirling in the processing chamber 6 and then cooled.
The hot air for heat-treating the supplied resin particles is supplied from the hot air supply means 7, distributed by the distribution member 12, and swirled in the processing chamber 6 by the swirling member 13 for swirling the hot air. Will be introduced. As its configuration, the swirling member 13 for swirling the hot air has a plurality of blades, and the swirling 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 6 at the outlet of the hot air supply means 7 is preferably 100° C. or higher and 300° C. or lower, and more preferably 130° C. or higher and 170° C. or lower. When the temperature at the outlet of the hot air supply means 7 is within the above range, it is possible to uniformly treat the particles while preventing fusion or coalescence of the particles due to overheating of the resin particles.

The hot air is supplied from the hot air supply means 7. The heat-treated resin particles that have been further heat-treated are 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. or higher and 30° C. or lower. If the temperature of the cold air is within the above range, the heat-treated resin particles can be efficiently cooled, and the fusion and coalescence of the heat-treated resin particles can be prevented without disturbing the uniform heat treatment of the resin particles. You can Further, the absolute water content of the cold air is preferably 0.5 g/m ³ or more and 15.0 g/m ³ or less.
Next, the cooled heat-treated resin particles are recovered by the recovery means 10 at the lower end of the processing chamber 6. A blower (not shown) is provided at the tip of the collecting means 10 so that suction and conveyance are carried out.

Further, the powder particle supply port 14 is provided so that the swirling direction of the supplied resin particles and the swirling direction of the hot air are the same direction, and the collecting means 10 also maintains the swirling direction of the swirled resin particles. Thus, the outer peripheral portion of the processing chamber 6 is provided tangentially. Further, the cold air supplied from the cold air supply means 8 is configured to be horizontally and tangentially supplied from the outer peripheral portion of the apparatus to the peripheral surface of the processing chamber. The swirl direction of the resin particles before the heat treatment supplied from the powder particle supply port 14, the swirl direction of the cold air supplied from the cold air supply unit 8, and the swirl direction of the hot air supplied from the hot air supply unit 7 are all in the same direction. Therefore, turbulent flow does not occur in the processing chamber, the swirling flow in the apparatus is strengthened, a strong centrifugal force is applied to the pre-heat treatment resin particles, and the dispersibility of the pre-heat treatment resin particles is further improved, resulting in less coalescence particles. Thus, heat-treated resin particles having a uniform shape can be obtained.
The heat treatment step may be performed after the fine pulverization or classification.

<Measurement of glass transition temperature (Tg) of resin>
The glass transition temperature of the resin is measured according to ASTM D3418-82 using a differential scanning calorimeter "Q1000" (manufactured by TA Instruments).
The melting point of indium and zinc is used to correct the temperature of the device detection unit, and the heat of fusion of indium is used to correct the amount of heat.

Specifically, about 5 mg of resin is precisely weighed and placed in an aluminum pan, and an empty aluminum pan is used as a reference, and the temperature rising rate is 10° C./min in the measurement range of 30 to 200° C. Measure with. The temperature is once raised to 180° C. and held for 10 minutes, then lowered to 30° C., and then raised again. In the second heating process, a specific heat change is obtained in the temperature range of 30 to 100°C. The straight line extending the baseline before the specific heat change at this time is the first straight line, and the straight line extending the baseline after the specific heat change is the second straight line, the first straight line and the second straight line. A straight line that is equidistant from the straight line in the vertical axis direction is referred to as a third straight line. The temperature at the intersection of the third straight line and the stepwise change portion of the differential thermal curve (so-called midpoint glass transition temperature) is the glass transition temperature (Tg) of the resin.

<Measurement of DSC endothermic amount (ΔH) of wax and cholesterol derivative>
The peak temperature (Tp) of the maximum endothermic peak of the toner and the like in the present invention is measured under the following conditions using DSC Q1000 (manufactured by TA Instruments).
Temperature rising rate: 10°C/min Measurement start temperature: 20°C
Measurement end temperature: 180°C
The melting point of indium and zinc is used to correct the temperature of the device detection unit, and the heat of fusion of indium is used to correct the amount of heat.
Specifically, about 5 mg of a sample is precisely weighed, placed in a silver pan, and measured once. An empty silver pan is used as a reference.

When the toner is used as a sample and the maximum endothermic peak derived from the binder resin does not overlap with the endothermic peaks of the resins other than the wax and the crystalline resin, the endothermic amount of the obtained maximum endothermic peak is used as it is for the wax and the crystal. Treated as the endothermic amount of the maximum endothermic peak derived from the organic resin. On the other hand, in the case where the toner is used as a sample, if the endothermic peak of the resin other than the wax and the binder resin overlaps with the maximum endothermic peak of the binder resin, the endothermic amount derived from the resin other than the wax and the binder resin is determined. , It is necessary to subtract from the obtained endothermic amount of the maximum endothermic peak.
The maximum endothermic peak means a peak having the maximum endothermic amount when there are a plurality of peaks. Further, the endothermic amount (ΔH) of the maximum endothermic peak is calculated from the area of the peak by using the analysis software attached to the apparatus.

<Measurement of molecular weight of resin by GPC>
The molecular weight distribution of the THF-soluble component of the resin is measured by gel permeation chromatography (GPC) as follows.
First, the toner is dissolved in tetrahydrofuran (THF) at room temperature for 24 hours. Then, the obtained solution is filtered through a solvent-resistant membrane filter “Maeshoridisc” (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. This sample solution is used for measurement under the following conditions.

Device: HLC8120 GPC (detector: RI) (manufactured by Tosoh Corporation)
Column: Shodex KF-801, 802, 803, 804, 805, 806, and 807 (manufactured by Showa Denko KK)
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 mL/min Oven temperature: 40.0°C
Sample injection volume: 0.10mL

In calculating the molecular weight of the sample, a 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 is used.

<Measuring method of softening point of resin>
The softening point of the resin is measured using a constant load extrusion type capillary rheometer "Flow characteristic evaluation device Flow tester CFT-500D" (manufactured by Shimadzu Corporation) according to the manual attached to the device. With this device, while applying a constant load from the top of the measurement sample by the piston, the temperature rises and melts the measurement sample filled in the cylinder, and the molten 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 apparatus Flow Tester CFT-500D" is defined as the softening point. The melting temperature in the ½ method is calculated as follows. First, 1/2 of the difference between the piston drop amount Smax at the time when the outflow ends and the piston drop amount Smin at the time when the outflow starts (this is X. X=(Smax-Smin)/ 2). The temperature of the flow curve when the piston drop amount is X in the flow curve is the melting temperature in the 1/2 method.

As a measurement sample, about 1.0 g of resin is compression-molded at about 10 MPa for about 60 seconds in a 25° C. environment using a tablet molding compressor (for example, NT-100H, manufactured by NPA System Co., Ltd.). However, a cylindrical column having a diameter of about 8 mm is used.
The measurement conditions of CFT-500D are as follows.

Test mode: Temperature rising method start temperature: 50°C
Ultimate temperature: 200℃
Measurement interval: 1.0°C
Temperature rising 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 Diameter of die hole: 1.0mm
Die length: 1.0mm

<Method of measuring weight average particle diameter (D4) of toner particles>
The weight average particle diameter (D4) of the toner particles is the same as that of a precise particle size distribution measuring apparatus “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) equipped with an aperture tube of 100 μm by a pore electrical resistance method. Measured with 25,000 effective measurement channels using the attached dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter Co., Ltd.) for setting measurement conditions and analyzing measurement data. Then, the measurement data is analyzed and calculated.

The electrolytic aqueous solution used for the measurement may be prepared by dissolving special grade sodium chloride in ion-exchanged water to a concentration of about 1% by mass, for example, "ISOTON II" (manufactured by Beckman Coulter, Inc.). .
Before the measurement and analysis, the dedicated software is set as follows.

On the "Change standard measurement method (SOM) screen" of the dedicated software, set the total count number in the control mode to 50,000 particles, set the number of measurements once, and set the Kd value to "standard particles 10.0 μm" (Beckman Coulter). (Manufactured by Co., Ltd.) is used to set the value obtained. The threshold and noise level are automatically set by pressing the threshold/noise level measurement button. Further, the current is set to 1600 μA, the gain is set to 2, and the electrolyte is set to ISOTON II, and the flash of the aperture tube after the measurement is checked.
On the "pulse-to-particle size conversion setting screen" of the dedicated software, 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 measuring method is as follows.

(1) Approximately 200 mL of the electrolytic aqueous solution was placed in a glass 250 mL round-bottom beaker dedicated to Multisizer 3, set on a sample stand, and the stirrer rod was stirred counterclockwise at 24 rpm. Then, the dirt and air bubbles in the aperture tube are removed by the "aperture flush" function of the analysis software.
(2) About 30 mL of the electrolytic aqueous solution is placed in a glass 100 mL flat-bottom beaker. In this, as a dispersant, "contaminone N" (a nonionic surfactant, anionic surfactant, 10% by weight aqueous solution of a neutral detergent for washing precision measuring instruments of pH 7 comprising an organic builder, Wako Pure Chemical Industries, Ltd. )) was diluted 3 times by mass with ion-exchanged water, and about 0.3 mL of a diluted solution was added.

(3) Two oscillators with an oscillating frequency of 50 kHz are installed with their phases shifted by 180 degrees, and an ultrasonic disperser “Ultrasonic Dispersion System Tetra 150” (manufactured by Nikkaki Bios Co., Ltd.) with an electric output of 120 W is used. .. A predetermined amount of ion-exchanged water is placed in the water tank of this ultrasonic disperser, and about 2 mL of the Contaminone N is added to the water tank.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. Then, the height position of the beaker is adjusted so that the resonance state of the liquid level of the electrolytic aqueous solution in the beaker becomes maximum.

(5) About 10 mg of the toner is added little by little to the electrolytic aqueous solution in a state where the electrolytic aqueous solution in the beaker of the above (4) is irradiated with ultrasonic waves and dispersed. Then, the ultrasonic dispersion treatment is continued for another 60 seconds. In the ultrasonic dispersion, the water temperature in the water tank is appropriately adjusted so as to be 10°C or higher and 40°C or lower.
(6) Using a pipette, drop the toner-dispersed aqueous electrolyte solution of (5) into the round-bottom beaker of (1) installed in the sample stand, and adjust so that the measured concentration is about 5%. .. Then, the measurement is performed until the number of measured particles reaches 50,000.
(7) The measurement data is analyzed by the dedicated software attached to the apparatus 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 with the dedicated software is the weight average particle diameter (D4).

<Measuring method of average circularity>
The average circularity of the toner particles is measured by a flow type particle image analyzer "FPIA-3000" (manufactured by Sysmex Corporation) under the measurement and analysis conditions during the calibration work.
The specific measuring method is as follows. First, about 20 mL of ion-exchanged water from which impure solids and the like have been removed beforehand is placed in a glass container. In this, as a dispersant, "contaminone N" (a nonionic surfactant, an anionic surfactant, a 10 mass% aqueous solution of a neutral detergent for washing precision measuring instruments of pH 7 comprising an organic builder, Wako Pure Chemical Industries, Ltd. )) was diluted about 3 times by mass with ion-exchanged water, and about 0.2 mL of a diluted solution was added. Further, about 0.02 g of a measurement sample is added, and dispersion treatment is performed for 2 minutes using an ultrasonic disperser to obtain a dispersion liquid for measurement. At that time, the dispersion is appropriately cooled so that the temperature of the dispersion becomes 10° C. or higher and 40° C. or lower. As the ultrasonic disperser, a tabletop type ultrasonic cleaner disperser (“VS-150” (manufactured by Vervoclear Co., Ltd.)) with an oscillation frequency of 50 kHz and an electric output of 150 W was used, and a predetermined amount was placed in the water tank. Ion-exchanged water is added, and about 2 mL of the Contaminone N is added to the water tank.

The flow-type particle image analyzer equipped with a standard objective lens (10 times) was used for the measurement, and the particle sheath “PSE-900A” (manufactured by Sysmex Corporation) was used as the sheath liquid. The dispersion prepared according to the above procedure is introduced into the flow-type particle image analyzer, and 3000 toner particles are measured in the HPF measurement mode and the total count mode. Then, the binarization threshold at the time of particle analysis is set to 85%, the analyzed particle diameter is limited to the circle equivalent diameter of 1.985 μm or more and less than 39.69 μm, and the average circularity of the toner particles is obtained.

Before measurement, the standard latex particles below are used for automatic focus adjustment.
-Standard latex particles: "RESEARCH AND TEST PARTICLES Latex Microsphere Suspensions 5200A" manufactured by Duke Scientific Co., Ltd. diluted with ion-exchanged water.
After that, it is preferable to perform focus adjustment every two hours from the start of measurement.
In the examples of the present application, a flow-type particle image analyzer which has been calibrated by Sysmex Corporation and has been issued a calibration certificate issued by Sysmex Corporation was used. The measurement was performed under the conditions and the analysis conditions when the calibration certificate was received, except that the analysis particle size was limited to the equivalent circle diameter of 1.985 μm or more and less than 39.69 μm.

<Cholesterol and cholesterol derivatives>
The structures and melting points of cholesterol and cholesterol derivatives used in this example are shown in Table 1 below.

<Production Example of Polymer 1>
In an autoclave reaction tank equipped with a thermometer and a stirrer, 300 parts by mass of xylene and 10 parts by mass of polypropylene (melting point 75° C.) were sufficiently dissolved and replaced with nitrogen. Then, a mixed solution of 73.0 parts by mass of styrene, 5.0 parts by mass of cyclohexyl methacrylate, 12.0 parts by mass of butyl acrylate, and 250 parts by mass of xylene was added dropwise at 180° C. for 3 hours for polymerization. Further, the temperature was maintained for 30 minutes, and the solvent was removed to obtain a polymer 1. The weight average molecular weight Mw of the obtained polymer 1 was 1.5×10 ⁴ .

<Production Example of Polymer 2>
In an autoclave reaction tank equipped with a thermometer and a stirrer, 600 parts by mass of xylene and 120 parts by mass of polyethylene (melting point 128° C.) were sufficiently dissolved and replaced with nitrogen. Then, a mixed solution of 1900 parts by mass of styrene, 170 parts by mass of acrylonitrile, 240 parts by mass of monobutyl maleate, 78 parts by mass of di-t-butylperoxyhexahydroterephthalate, 24.0 parts by mass of butyl acrylate, and 455 parts by mass of xylene. Polymerization was performed by dropping at 160° C. for 2 hours. Further, the temperature was maintained for 30 minutes, and the solvent was removed to obtain a polymer 2. The weight average molecular weight Mw of the obtained polymer 2 was 4.0×10 ³ .

<Production Example of Amorphous Polyester Resin A>
After replacing a 5 L four-necked flask equipped with a nitrogen introducing tube, a cooling tube, a stirrer and a thermocouple with nitrogen, the raw material monomers and tin octylate (II) shown in Table 2 were charged and the temperature was raised to 180°C. Then, the mixture was reacted for 10 hours. After further reacting at 15 mmHg for 5 hours, as a second reaction step, trimellitic anhydride was added according to Table 2 and reacted at 180° C. for 3 hours to obtain an amorphous polyester resin A. The resin properties are shown in Table 2.

<Production Example of Amorphous Polyester Resin B>
Using the raw materials shown in Table 2, it was confirmed that the softening point measured according to ASTM D36-86 reached the desired temperature shown in Table 2 in the second reaction step, and the resin A was used except for stopping the reaction. Resin B was obtained in substantially the same manner as in the production example of. The resin properties are shown in Table 2.

<Production Example of Toner 1>
-Amorphous polyester resin A 62.5 parts by mass-Amorphous polyester resin B 30.0 parts by mass-Cholesterol derivative 1 10.0 parts by mass-Polymer 1 10.0 parts by mass
・Wax (HNP51 Nippon Seiro Co., Ltd.) 5.0 parts by mass ・Carbon black Nipex35 (manufactured by Degussa) 9.0 parts by mass ・3,5-di-t-butylsalicylic acid aluminum compound (Bontron E88 Orient Chemical Industry ( Co., Ltd.) 0.3 parts by mass

The above materials were mixed using a Henschel mixer (FM-75 type, manufactured by Mitsui Mining Co., Ltd.) at a rotation speed of 20 s ⁻¹ and a rotation time of 5 minutes, and then a twin-screw kneader (PCM-) set at a temperature of 145° C. 30 type, manufactured by Ikegai Co., Ltd.). The obtained kneaded product was cooled and coarsely pulverized with a hammer mill to 1 mm or less to obtain a coarsely pulverized product. The obtained coarsely pulverized product was finely pulverized by a mechanical pulverizer (T-250, manufactured by Freund Turbo Co., Ltd.). Further, using a Faculty F-300 (manufactured by Hosokawa Micron Co., Ltd.), classification was performed to obtain toner particles 1. The operating conditions were a classification rotor rotation speed of 130 s ⁻¹ and a dispersion rotor rotation speed of 120 s ⁻¹ . Further, the fine particle side powder separated from the toner particles 1 in the classification step was separately collected and subjected to analysis.

The obtained toner particles 1 were subjected to thermal sphering treatment. Heat treatment was performed using the heat treatment apparatus shown in FIG. 1 to obtain heat-treated toner particles. The operating conditions were a feed rate of 5 kg/hour, a hot air temperature C of 170° C., a hot air flow rate of 6 m ³ /min, a cold air temperature E of −5° C., a cold air flow rate of 4 m ³ /min, and a blower air flow rate of 20 m ³ / Min, and the injection air flow rate was 1 m ³ /min.

The heat treatment the toner particles of 100 parts by weight to 100 parts by weight of hydrophobic silica ^(BET: 200m 2 /g)1.0 parts by mass of titanium oxide fine particles surface-treated with isobutyl trimethoxysilane (BET: ^80m 2 / g) Was mixed with 1.0 parts by mass of a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Kakoki Co., Ltd.) at a rotation speed of 30 s ⁻¹ and a rotation time of 10 minutes to obtain a toner 1. The weight average particle diameter (D4) of Toner 1 was 6.2 μm, and the average circularity was 0.970. The physical properties of the toner are shown in Table 3. BET is a specific surface area (m ² /g) by nitrogen adsorption measured by the BET method.

<Production Example of Toners 2 to 15>
Toners 2 to 15 were obtained in substantially the same manner as in the production example of Toner 1, except that the materials described in Table 3 were blended according to Table 3 in the production example of Toner 1.

<Production Example of Magnetic Core Particle 1>
・Process 1 (weighing/mixing process):
Fe ₂ O ₃ 62.7 parts by mass MnCO ₃ 29.5 parts by mass Mg(OH) ₂ 6.8 parts by mass SrCO ₃ 1.0 part by mass Ferrite raw materials were weighed so that the above materials had the above composition ratio. Then, it was pulverized and mixed for 5 hours by a dry vibration mill using stainless beads having a diameter of 1/8 inch.

・Process 2 (temporary baking process):
The obtained pulverized product was made into pellets of about 1 mm square with a roller compactor. Coarse powder was removed from the pellets using a vibrating screen with an opening of 3 mm, and then fine powder was removed using a vibrating screen with an opening of 0.5 mm. Then, using a burner type firing furnace, under a nitrogen atmosphere (oxygen concentration: 0. (01 vol%) at a temperature of 1000° C. for 4 hours to prepare a calcined ferrite. The composition of the obtained calcined ferrite was as follows.
(MnO) _a (MgO) _b (SrO) _c (Fe ₂ O ₃ ) _d
In the above formula, a=0.257, b=0.117, c=0.007, d=0.393

・Process 3 (crushing process):
After crushing to about 0.3 mm with a crusher, 30 parts by mass of water was added to 100 parts by mass of calcined ferrite using zirconia beads having a diameter of 1/8 inch, and crushed for 1 hour with a wet ball mill. The slurry was pulverized for 4 hours by a wet ball mill using alumina beads having a diameter of 1/16 inch to obtain a ferrite slurry (a finely pulverized product of calcined ferrite).

・Process 4 (granulation process):
To the ferrite slurry, 1.0 parts by mass of ammonium polycarboxylate as a dispersant and 2.0 parts by mass of polyvinyl alcohol as a binder were added to 100 parts by mass of calcined ferrite, and a spray dryer (manufacturer: Okawara Kakoki Co., Ltd.). ), it was granulated into spherical particles. After adjusting the particle size of the obtained particles, it was heated at 650° C. for 2 hours using a rotary kiln to remove the organic components of the dispersant and the binder.

・Process 5 (firing process):
In order to control the firing atmosphere, the temperature was raised from room temperature to a temperature of 1300°C over 2 hours in a nitrogen atmosphere (oxygen concentration of 1.00% by volume) in an electric furnace, and then the firing was performed at a temperature of 1150°C for 4 hours. .. Thereafter, the temperature was lowered to 60° C. over 4 hours, the nitrogen atmosphere was returned to the atmosphere, and the sample was taken out at a temperature of 40° C. or lower.

・Process 6 (selection process):
After disintegrating the agglomerated particles, a low magnetic force product is cut by magnetic separation, coarse particles are removed by sieving with a sieve having an opening of 250 μm, and 50% particle size (D50) of 37.0 μm based on volume distribution. Magnetic core particles 1 were obtained.

<Preparation of coating resin 1>
Cyclohexyl methacrylate monomer 26.8 mass%
Methyl methacrylate monomer 0.2 mass%
Methyl methacrylate macromonomer 8.4 mass%
(Macromonomer having methacryloyl group at one end and having a weight average molecular weight of 5000)
Toluene 31.3% by mass
Methyl ethyl ketone 31.3% by mass
Azobisisobutyronitrile 2.0 mass%

Of the above materials, cyclohexylmethacrylate, methylmethacrylate, methylmethacrylate macromonomer, toluene, and methylethylketone were placed in a four-necked separable flask equipped with a reflux condenser, a thermometer, a nitrogen introduction tube, and a stirring device. Then, nitrogen gas was introduced to replace the inside of the system with nitrogen gas. Then, the mixture was heated to 80° C., azobisisobutyronitrile was added, and the mixture was refluxed for 5 hours for polymerization. Hexane was injected into the obtained reaction product to precipitate a copolymer, and the precipitate was filtered off and dried in vacuum to obtain a coating resin 1.
The obtained coating resin 1 was dissolved in 30 parts by mass, toluene 40 parts by mass, and methyl ethyl ketone 30 parts by mass to obtain a polymer solution 1 (solid content 30% by mass).

<Preparation of coating resin solution 1>
Polymer solution 1 (resin solid content concentration 30 mass%) 33.3 mass%
Toluene 66.4% by mass
Carbon black (Regal 330; manufactured by Cabot) 0.3% by mass
(Primary particle size 25 nm, nitrogen adsorption specific surface area 94 m ² /g, DBP oil absorption 75 mL/100 g)
The above materials were dispersed for 1 hour with a paint shaker using zirconia beads having a diameter of 0.5 mm. The obtained dispersion liquid was filtered through a 5.0 μm membrane filter to obtain a coating resin solution 1.

<Production Example of Magnetic Carrier 1>
(Resin coating process):
The coating resin solution 1 was added to a vacuum degassing type kneader maintained at room temperature so as to be 2.5 parts by mass as a resin component with respect to 100 parts by mass of the filled core particles 1. After charging, the mixture was stirred at a rotation speed of 30 rpm for 15 minutes, the solvent was volatilized at a certain level (80% by mass), the temperature was raised to 80° C. while mixing under reduced pressure, the toluene was distilled off over 2 hours, and then the mixture was cooled. The magnetic carrier thus obtained is separated into low-magnetic products by magnetic separation, passed through a sieve having an opening of 70 μm, and then classified by an air classifier, and a magnetic carrier having a volume distribution-based 50% particle diameter (D50) of 38.2 μm. Got 1.

<Production Example of Two-Component Developer 1>
To 92.0 parts by mass of the magnetic carrier 1, 8.0 parts by mass of the toner 1 were added and mixed by a V-type mixer (V-20, manufactured by Seishin Enterprise Co., Ltd.) to obtain a two-component developer 1. It was

<Production Example of Two-Component Developers 2 to 15>
Two-component developers 2 to 15 were obtained in the same manner as in the production example of the two-component developer 1, except that the combination of toners was changed as shown in Table 4.

[Example 1]
The two-component developer 1 was used for evaluation.
As the image forming apparatus, a digital commercial printing printer imageRUNNER ADVANCE C9075 PRO remodeled by Canon Inc. was used, and the two-component developer was put in the developing device at the cyan position. Then, the DC voltage VDC of the developer carrying member, the charging voltage VD of the electrostatic latent image carrying member, and the laser power are adjusted so that the amount of toner deposited on the electrostatic latent image carrying member or paper becomes desired, and the evaluation described later is performed. I went. The modification point is that the fixing temperature and the process speed can be freely set.
Evaluation was carried out based on the following evaluation methods, and the results are shown in Table 4.

<Evaluation 1: Blocking resistance (residual rate)>
5 g of toner is put in a 100 mL plastic container (resin cup) and left in a temperature and humidity variable type thermostat (setting; temperature 55° C., relative humidity 41%) for 48 hours. evaluated.
The cohesiveness was evaluated by using the powder tester PT-X manufactured by Hosokawa Micron Co., Ltd. as a valuation index for the residual ratio of the toner remaining after sieving with a mesh having a mesh size of 20 μm for 10 seconds at an amplitude of 0.5 mm.

(Evaluation criteria)
A: The residual rate is less than 2.0% B: The residual rate is 2.0% or more and less than 10.0% C: The residual rate is 10.0% or more and less than 15.0% D: The residual rate is 15.0 %that's all

<Evaluation 2: Chargeability (charge retention rate)>
The toner on the electrostatic latent image bearing member was suctioned and collected using a metal cylindrical tube and a cylindrical filter to calculate the triboelectric charge amount and the toner deposit amount of the toner.
Specifically, the triboelectrification amount of the toner on the electrostatic latent image carrier and the toner deposition amount were measured by a Faraday-Cage.

The Faraday cage is a coaxial double cylinder in which the inner cylinder and the outer cylinder are insulated. If a charged body having a charge amount Q is put in the inner cylinder, it is as if a metal cylinder having a charge amount Q exists due to electrostatic induction. The amount of this induced charge was measured with an electrometer (Kesley 6517A, made by Kessley), and the amount of charges Q (mC) divided by the toner mass M (kg) in the inner cylinder (Q/M) was used to triboelectrically charge the toner. And quantity.

In addition, by measuring the sucked area S, the toner mass M was divided by the sucked area S (cm ² ) to obtain the amount of applied toner per unit area.
The toner stops the rotation of the electrostatic latent image bearing member before the toner layer formed on the electrostatic latent image bearing member is transferred to the intermediate transfer member, and the toner image on the electrostatic latent image bearing member is directly blown by air. It was sucked and measured.
Amount of applied toner (mg/cm ² )=M/S
Toner triboelectric charge amount (mC/kg)=Q/M

In the above image forming apparatus, the amount of toner deposited on the electrostatic latent image carrier is adjusted to 0.35 mg/cm ² under a high temperature and high humidity environment (temperature 32.5° C., relative humidity 80%), It was suctioned and collected by the metal cylindrical tube and the cylindrical filter. At that time, the charge amount Q accumulated in the condenser and the toner mass M collected through the metal cylindrical tube are measured, and the charge amount Q/M (mC/kg) per unit mass is calculated to obtain the electrostatic latent image. The amount of charge per unit mass on the carrier Q/M (mC/kg) was used (initial evaluation).

After performing the above-described evaluation (initial evaluation), the developing device was removed from the machine, left standing in a high temperature and high humidity environment (temperature 32.5°C, relative humidity 80%) for 72 hours, and then the developing device was placed in the machine again. I put it on. Then, the charge amount Q/M per unit mass on the electrostatic latent image carrier was measured at the same DC voltage VDC as in the initial evaluation (evaluation after standing).
Q/M per unit mass on the electrostatic latent image carrier in the above initial evaluation is 100%, and the charge per unit mass on the electrostatic latent image carrier after standing for 72 hours (evaluation after standing) The maintenance rate of the quantity Q/M (evaluation after standing/initial evaluation×100) was calculated and judged according to the following criteria.

(Evaluation criteria)
A: Maintenance rate is 80% or more B: Maintenance rate is 70% or more and less than 80% C: Maintenance rate is 60% or more and less than 70% D: Maintenance rate is less than 60%

<Evaluation 3: Low temperature fixability (fixable minimum temperature)>
A full-color copying machine imagePRESS C1+ manufactured by Canon Inc. was equipped with a developing device containing the two-component developer 1 in the cyan station, and was modified so that an image could be formed with the fixing device removed. Then, an unfixed toner image (hereinafter, unfixed image) was formed on the evaluation paper. For the evaluation, plain paper GF-C104 (A4104 g/cm ² ) for color copying machine/printer (sold by Canon Marketing Japan Inc.) was used.
Actually, the developing conditions were appropriately adjusted so that the amount of toner on the paper of the FFh image was 1.2 mg/cm ² , 3 cm from the tip of the A4 portrait evaluation paper, and 2 cm×10 cm at the center position of the evaluation paper. An unfixed image was formed. The unfixed image was conditioned under a low humidity and low temperature environment (temperature 15° C./10% relative humidity) for 24 hours. Note that FFh is a value in which 256 gradations are displayed in hexadecimal notation, 00h is the first gradation of 256 gradations (white background portion), and FFh is the 256th gradation of 256 gradations (solid portion). Is.

Subsequently, the fixing device was taken out from the full-color copying machine image RUNNER ADVANCE C9075PRO manufactured by Canon Inc., and a fixing test jig was prepared so that the process speed and the upper and lower fixing member temperatures could be controlled independently. The fixing property evaluation was carried out in a low temperature and low humidity environment (temperature 15° C./relative humidity 10%), and the fixing test jig prepared by adjusting the process speed to 450 mm/sec was used. In the actual evaluation, the unfixed image was passed through while adjusting the upper belt temperature of the fixing test jig in the range of 100° C. to 200° C. at 5° C. intervals, while the lower belt temperature was fixed at 100° C. The condition was evaluated. The fixed image passed through the fixing device is rubbed 5 times with a lens cleaning wiper (manufactured by Dasper Ozu Sangyo Co., Ltd.) loaded with a load of 4.9 kPa, and the density decrease rate of the image density before and after the rubbing is 10% or less. Is the fixing temperature. Based on the criterion that the image cannot be fixed when the density is reduced more than 10%, the lowest upper belt setting temperature that does not exceed the image density reduction rate of 10% is set as the low temperature fixing temperature, and the image is evaluated according to the following evaluation criteria. ..

(Evaluation criteria: low temperature fixability)
A: less than 120°C B: 120°C or more and less than 140°C C: 140°C or more and less than 160°C D: 160°C or more

<Evaluation 4: Fixed image storability>
A temperature higher than the minimum fixing temperature by 20°C is set as the proper fixing temperature, and plain paper for color copiers/printers GF-C104 (A4 104 g/cm ² ) (sold by Canon Marketing Japan Co., Ltd.) and A4 single-sided ^Two solid images (4 cm×4 cm) having a toner application amount of 0.90 mg/cm ² were formed on the sheet. The recording papers on which the solid images were formed were overlapped face-to-face so that the solid images were in contact with each other, and a vertical load of 100 g/cm ² was applied, and the recording papers were allowed to stand for one day in an environment of a temperature of 55° C./relative humidity of 41%. After that, two images were peeled off, and defects on the surface of the image due to image adhesion were evaluated.

(Evaluation criteria: Fixed image storability)
A: There is no image defect.
B: A portion where the gloss of the image is changed (the area ratio where the gloss degree is changed is less than 5%) is partially observed.
C: Image defects such as reduction in image gloss (area ratio of 5% or more and less than 10%) are recognized.
D: There are many image defects.

[Examples 2 to 12, Comparative Examples 1 to 3]
The two-component developers 2 to 15 shown in Table 4 were used and evaluated in the same manner as in Example 1. The evaluation results are shown in Table 4.

1. Raw material quantitative supply means 2. Compressed gas flow rate adjusting means, 3. Introductory pipe, 4. Protruding member, 5. Supply pipe, 6. Processing chamber, 7. Hot air supply means, 8. Cold air supply means, 9. Regulatory means, 10. Collection means, 11. Hot air supply means outlet, 12. Distribution member, 13. Turning member, 14. Powder particle supply port,

Claims (5)

A toner comprising a binder resin, a colorant, a polymer having a styrene-acrylic polymer portion and a polyolefin portion, and toner particles containing cholesterol or a cholesterol derivative. The toner according to claim 1, wherein the melting point of the cholesterol or cholesterol derivative is 80° C. or higher and 130° C. or lower. The toner according to claim 1 or 2, wherein the styrene-acrylic polymer portion of the polymer contains a unit derived from a saturated alicyclic compound. The toner according to claim 1, wherein the cholesterol or cholesterol derivative is a fatty acid cholesteryl ester compound in which a fatty acid and cholesterol are condensed. The content of the cholesterol or cholesterol derivative is 1.0 part by mass or more and 30.0 parts by mass or less based on 100.0 parts by mass of the binder resin,
When the content of the polymer having the styrene-acrylic polymer part and the polyolefin part is Dw [mass %], and the content of the cholesterol or the cholesterol derivative is Cw [mass %], the ratio of Dw and Cw (Dw /Cw) is 0.5 or more and 2.0 or less, The toner according to any one of claims 1 to 4.

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