JP3120644B2 - Toner for developing electrostatic latent images - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner used as a developer for developing an electrostatic latent image in electrophotography, electrostatic recording, electrostatic printing, and the like. And a toner for developing an electrostatic latent image.

[0002]

2. Description of the Related Art In developing an electrostatic latent image, a predetermined polarity is applied to an electrostatic latent image having a positive or negative charge formed on an electrostatic latent image carrier such as a photosensitive member by various methods. This is performed by electrostatically adsorbing the triboelectrically charged toner, and then transferring and fixing the toner image on a transfer paper to form a developed image.

The toner used for developing such an electrostatic latent image is first required to have an appropriate charge amount in order to obtain a clear developed image without fog or the like. Further, it is also required that the charge amount does not change with time, and that the charge amount does not significantly change or change due to environmental changes, for example, humidity change. This is because if the charge amount attenuates from the initially set value and becomes smaller, toner scattering increases, causing problems such as background fog and toner contamination around the developing device.

In order to meet the above demand, a charge control agent is usually added to the toner. However, in recent years, the demand for color image reproduction has been increased, and the charge of white or light yellow or the like has been increased so as not to impair the color reproducibility. Control agents are required.

[0005] Colorless, white, and pale yellow negative charge control agents which impart a negative charge are commercially available, but most are compounds of alloys containing heavy metals, for example, complexes or salts containing chromium. In particular, from the viewpoint of safety, a metal-free negative charge control agent containing no heavy metal is demanded.

On the other hand, Japanese Patent Application Laid-Open No. Hei 2-201378 proposes a calixarene compound as a negative charge control agent containing no heavy metal and having excellent properties such as safety, chargeability and environmental stability.

However, when the above calixarene compound is actually mixed with a toner composition such as a resin and a colorant and kneaded, and then the kneaded material is pulverized to produce toner, the charge characteristics and the like of each toner particle are reduced. The toner performance varies, resulting in problems such as toner scattering and toner fog in the copied image.

In particular, when the above toner is used as a full-color toner, full-color images are usually reproduced by superimposing toners of cyan, magenta, yellow and black. The amount of toner fogging becomes very large, which causes a problem that image quality is impaired.

When the above toner is used in a two-component developer, spent image formation is repeated, and the calixarene compound is released from the toner and adheres to the carrier. There is also a problem that the charging performance for the toner is deteriorated and the life of the developer is shortened.

[0010]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and has a uniform charging performance, does not generate toner fog, and has excellent environmental stability and safety. The purpose is to provide.

A further object of the present invention is to provide a color toner which is excellent in color tone and capable of reproducing an excellent image without fog.

Another object of the present invention is to provide a toner which does not cause spent of a calixarene compound on a carrier even when used as a two-component developer and has excellent durability. .

[0013]

According to the present invention, there is provided a toner in which at least a colorant and a charge control agent are dispersed in a binder resin, wherein the charge control agent is a calixarene compound, and the calixarene compound is dispersed in the toner. The calixarene compound has an average particle size of 1.0 μm or less;
The present invention relates to a toner for developing an electrostatic latent image having a calixarene compound content of 1 μm or more in a number ratio of 1% or less.

The present inventors have conducted intensive studies on a toner using a calixarene compound as a charge control agent, and found that the dispersion state of the calixarene compound in the toner affects the charging characteristics and the like of the toner. The present inventors have found that the problem can be solved by setting the dispersed particle size distribution of the calixarene compound in the toner to a specific range, and have reached the present invention.

In the toner of the present invention, at least the calixarene compound is dispersed in the binder resin in the form of fine particles.

In the present invention, the calixarene compound contains particles having an average particle diameter of 1.0 μm or less, preferably 0.7 μm or less, and a particle diameter of 2.0 μm or more in a binder resin in a number ratio of 1% or less, preferably 1% or less. It is dispersed so as to be 0.1% or less, more preferably 0%. By having such a particle size distribution, the calixarene compound is uniformly dispersed in the toner, the charge amount distribution of the toner can be narrowed, the rising characteristics of the charge are improved, and toner scattering and toner fog are generated. Can be prevented. In addition, since the dispersibility of the calixarene compound in the toner is improved, the amount of the calixarene compound liberated from the toner during printing is extremely small, and when the calixarene compound is used as a two-component developer, the calixarene compound is reduced. Since the spent on the carrier particles can be prevented, the durability of the developer is improved.

When used as a full-color toner, full-color images are usually reproduced by superimposing cyan, magenta, yellow and black toners. However, fog by one color toner is small. However, since the amount of fogging of the image increases due to the superposition of the respective colors, it is necessary to lower the toner fog as compared with the normal mono-color image reproduction. According to the toner of the present invention, toner fog can be successfully prevented,
It can be suitably used as a full-color toner.

When the average particle size of the calixarene compound dispersed in the toner is larger than 1.0 μm, or when the number ratio of particles having a particle size of 2.0 μm or more is more than 1%, the calixarene compound in the toner is The dispersibility of the compound becomes non-uniform, and the content and particle size of the calixarene compound in each toner particle vary. As a result, the charge amount distribution of the toner becomes broad, and toner scattering and toner fog occur.

In the toner of the present invention, the number ratio of the calixarene compound having an equivalent circular diameter of 1.0 μm or less is preferably 90% or more, more preferably 95% or more.

As the calixarene compound used in the present invention, for example, a calix (n) arene compound represented by the following general formula [I] can be used.

[0021]

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In the general formula [I], R ₁ and R ₅ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms or — (CH ₂ ) m COOR ₉ (R ₉ is a hydrogen atom or a lower alkyl group). And m represents an integer of 1 to 3), and R ₂ ,
R ₃ , R ₄ , R ₆ , R ₇ and R ₈ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group, an aryl group, a cyclohexyl group, a hydroxyl group, a carboxyl group, an alkyl group; Represents an amino group, a nitro group, a sulfone group, a sulfamide group, a carbamoyl group, a cyano group or an acyl group which may be substituted with a group and / or an acyl group. However, n = x + y, x is 4-8
And y is an integer of 0 to 4, and n is an integer of 4 to 8.

Examples of the calix (n) arene compound represented by the above general formula [I] include, but are not limited to, compounds shown in the following compound examples.

[0024]

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[0025]

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[0026]

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[0027]

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[0028]

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[0029]

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[0030]

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The calixarene compound is added in an amount of 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the binder resin.

The binder resin used for the toner is not particularly limited as long as it is generally used widely in toners. For example, styrene resins,
Acrylic resin, olefin resin, polyester resin, amide resin, thermoplastic resin such as polycarbonate resin, polyether, polysulfone, or epoxy resin, urea resin, urethane resin, etc. Thermosetting resins and their copolymers and polymer blends are used. As the binder resin used in the present invention, for example, not only those in a state of a perfect polymer as in a thermoplastic resin but also those in an oligomer or a prepolymer as in a thermosetting resin are included. And a polymer that partially contains a prepolymer, a crosslinking agent, and the like.

When a translucent color toner for OHP or full color is obtained, a polyester resin is used as a binder resin from the viewpoints of vinyl chloride resistance, translucency and adhesion to an OHP sheet. It is desirable to do. Further, in this case, the glass transition point is 55 to 70 ° C, the softening point is 80 to 150 ° C, and the number average molecular weight (Mn) is 2,0.
Desirably, the polyester is a linear polyester having a molecular weight distribution (Mw / Mn) of 4 or less. Also, a modified urethane modified polyester obtained by reacting a diisocyanate with a linear polyester, or a styrene, acrylic, aminoacrylic monomer or the like is copolymerized with a linear polyester by a method such as grafting or block polymerization to modify. Polymers having the same glass transition point, softening point, and molecular weight as those described above are also preferably used.

The coloring agents usable in the present invention include, for example, C.I. I. Pigment yellow-12, C.I. I. Pigment Yellow-13, Naft-Louiero-S, Hansaier-5G, Hansaier-
Red (magenta) pigments such as C.3G, Hansayero-G, Benzidine Yellow-G, and Vulcanfast Yellow-5G; I. Pigment Red 81, C.I. I. Pigment Red 122, C.I. I. Pigment Red 57: 1,
C. I. Pigment Red 49 and the like as blue (cyan) pigments such as C.I. I. Pigment Bull-15, C.I. I. Pigmentable-16, etc., but not limited to these pigments, and conventionally known pigments or dyes of each color can be used.

The amount of the coloring agent to be added depends on the amount of the binder resin 1
1 to 20 parts by weight, preferably 2-1 to 100 parts by weight
It is desirable to use in the range of 5 parts by weight. Addition amount is 1
If the amount is less than 10 parts by weight, a sufficient color tone and image density as a toner cannot be obtained.

The toner of the present invention may contain a post-treatment agent such as an anti-offset agent, a fluidizing agent or a cleaning aid.

Various waxes can be used as an anti-offset agent for improving the fixing property of the toner. Particularly, polyolefin waxes such as low molecular weight polypropylene, polyethylene, oxidized polypropylene and oxidized polyethylene, and furthermore, Natural waxes such as carnauba wax are preferably used. Offset inhibitor is 1 to 15 parts by weight, based on 100 parts by weight of the binder resin.
It is desirable to add 2 to 8 parts by weight.

As the fine particles for post-treatment, a fluidizing agent or a cleaning aid may be mixed with toner.

As the fluidizing agent, silica, aluminum oxide, titanium oxide, magnesium fluoride, silicon carbide,
Various inorganic fine particles such as boron carbide, titanium carbide, zirconium carbide, titanium nitride, zirconium nitride, magnetite, molybdenum disulfide, aluminum stearate, magnesium stearate, and zinc stearate are used alone or in combination. These fine particles are desirably subjected to a hydrophobizing treatment with a hydrophobizing agent such as a silane coupling agent, a titanium coupling agent, a higher fatty acid, or silicone oil. In particular, the above-mentioned inorganic fine particles subjected to a hydrophobic treatment are
It is preferable to use them in combination, and it is particularly preferable to use hydrophobic silica and hydrophobic aluminum oxide or hydrophobic silica and hydrophobic titanium oxide.

Examples of the cleaning aid include the above-mentioned inorganic fine particles as a fluidizing agent, metal soaps such as stearates, and the like.
Various synthetic resin fine particles such as fluorine-based, silicon-based, styrene-based, acrylic-based, styrene- (meth) acryl-based, benzoguanamine, melamine, and epoxy are used.

It is desirable to add 0.05 to 5 parts by weight, preferably 0.1 to 3 parts by weight, of the post-treatment agent to 100 parts by weight of the binder resin.

Usually, the toner is produced by mixing a colorant, a charge control agent and a binder resin, followed by melting and kneading, and then pulverizing and classifying the kneaded material. The calixarene compound, which is a charge control agent, has a crystal size of 2-1.
It has a wide particle size distribution in the range of 00 μm, and a large one has a particle size of about 70 to 100 μm. When the toner is produced by the above-described method, sufficient pressure is not applied to the calixarene compound during melting and kneading, so that the toner cannot be sufficiently pulverized. As a result, the calixarene compound content or the dispersed particle size of each toner particle varies, so that the charge distribution of the toner is widened, causing toner scattering and toner fogging. Affects durability at the time.

The toner of the present invention can be manufactured by the following method.

First, the calixarene compound and the binder resin are mixed at a weight ratio of 10:90 to 90:10, and then the mixture is heated and kneaded with a heating and pressure kneader. At this time, the temperature around the softening point of the binder resin (about 100 to 1)
It is desirable to perform the heating and pressure kneading at a temperature of 40 ° C), preferably ± 10 ° C. The pressure is 1 to 200
It is desirable to carry out in the range of Kg / m ³ . The kneading time is desirably in the range of 2 to 300 minutes. By selecting each condition within such a range, it is possible to obtain a calixarene compound-dispersed resin composition in which the calixarene compound particle size is not more than the average particle size of the toner to be produced, preferably 5 μm or less.

After this, kneading may be further performed with three rolls, so that the dispersed particle size of the calixarene compound can be further reduced.

The calixarene compound-dispersed resin composition thus obtained is cooled and pulverized to obtain calixarene compound-dispersed resin particles.

The obtained calixarene compound-dispersed resin particles, a binder resin, a colorant, and various additives such as an anti-offset agent, if necessary, are mixed, melted and kneaded, then cooled, and the kneaded product is pulverized. By performing the classification, a toner in which the calixarene compound has a predetermined dispersed particle size can be obtained.

The average particle diameter of the toner is preferably 5 to 15 μm. Particularly, when a high-definition image is reproduced,
The average particle size is desirably 5 to 9 μm, preferably 5 to 8 μm. In particular, in the case of a small particle size toner having an average particle size of about 5 to 9 μm, problems such as toner fog and density unevenness are likely to occur due to the small particle size. A small particle size toner having excellent characteristics can be obtained.

The toner obtained as described above may be used as a one-component developer or as a two-component developer together with a carrier.

[0050] As the carrier, those usually used such as an iron powder carrier, a ferrite carrier, a coating carrier and a binder type carrier can be used.

Specifically, ferrite carrier materials include metals such as iron, nickel, and cobalt, and zinc, antimony, aluminum, lead, tin, bismuth, beryllium, manganese, selenium, tungsten, zirconium, and the like.
Alloys or mixtures with metals such as vanadium, oxides,
Metal oxides such as titanium oxide and magnesium oxide; nitrides such as chromium nitride and vanadium nitride; mixtures with carbides such as silicon carbide and tungsten carbide; ferromagnetic ferrites; and mixtures thereof.

As the coating carrier, one coated with various synthetic resins or ceramic layers using iron or ferrite as a core material is used. Examples of the synthetic resin include a polystyrene resin, a poly (meth) acrylic resin, a polyolefin resin, a polyamide resin, a polycarbonate resin, a polyether resin, a polysulfonic acid resin, and a polyester resin. , Epoxy resins, polybutyral resins, urea resins, urethane / urea resins, silicone resins, polyethylene resins, Teflon resins, and other thermoplastic resins and thermosetting resins and mixtures thereof, and And copolymers, block polymers, graft polymers and polymer blends of these resins. Further, resins having various polar groups may be used to improve the chargeability. Further, in order to improve the chargeability and other various developer properties, various organic and / or inorganic materials may be dispersed and / or dissolved and coated, and these materials may be fixed on the surface of the coating carrier. A thing may be used.

Next, specific examples of the present invention will be described, and comparative examples will be given to clarify that the toner according to the examples of the present invention is excellent.

[0054]

【Example】

(Production of Calixarene-dispersed resin particles A) Styrene-
Acrylic acid copolymer (softening point: 120 ° C, glass transition point: 65 ° C, Mn: 16000, Mw / Mn: 2.1
8, hereinafter abbreviated as styrene-acrylic resin A) 1.4 kg
Was added with 0.6 kg of p-tert-butylcalix (8) arene (equivalent circular diameter of 2-80 μm) as a charge control agent, and mixed with a 9-liter Henschel mixer for 3 minutes. This mixture is heated at 110 ° C. with a heating / pressing kneader for 5 minutes.
Kneading under pressure of kg / m ² for 1 hour, cooling
The mixture was roughly pulverized with a mill to obtain calixarene-dispersed resin particles A having a calixarene content of 30% by weight. The calixarene compound in the resin particles has an average particle size of 2.0 μm,
The major axis was 10 μm or less.

The major axis of the calixarene compound is
A section of the resin in which the calixarene compound was dispersed was prepared by a microtrome, and the section was measured with an optical microscope photograph at a magnification of 600 times. The particle size is determined by dissolving the resin of the resin particles using a solvent (a mixed solvent of chloroform / ethanol) that dissolves the resin of the resin particles and does not dissolve the calixarene compound, (Centrifugal automatic particle size distribution analyzer: manufactured by Dig Seisakusho Co., Ltd.).

(Production of Calixarene dispersed resin particles B) Polyester resin (softening point: 110 ° C., glass transition point: 63 ° C., acid value: 10, hydroxyl value: 30, Mn: 400)
0, Mw / Mn: 2.84, a linear polyester; hereinafter, abbreviated as polyester resin A) (1.4 kg), 0.6 kg of p-tert-butylcalix (8) arene as a charge control agent, and 9 l Henschel mixer -Mix for 3 minutes. This mixture was kneaded with a heating / pressure kneader heated to 105 ° C. under a pressure of 4 kg / m ² for 1 hour, cooled, coarsely pulverized with a feather mill, and calixarene having a content of 30% by weight. Calixarene dispersed resin particles B were obtained.
The calixarene compound in the calixarene-dispersed resin particles B had an average particle diameter of 3.8 μm and a major axis of 10 μm or less.

(Production of calixarene dispersed resin particles C) To 1.4 kg of styrene-acrylic resin A, 0.6 kg of p-tert-butylcalix (8) arene was added as a charge control agent, and mixed with a 9-liter Henschel mixer for 3 minutes. I do. This mixture was kneaded with a twin screw extruder kneaded at 130 ° C., kneaded with three rolls heated at 130 ° C. for 10 minutes, cooled, coarsely pulverized with a feather mill, and calixarene content 30 By weight, calixarene-dispersed resin particles C were obtained. Calixarene dispersed resin particles C
The calixarene compound therein had an average particle diameter of 3.4 μm and a major axis of 8 μm or less.

(Production of Calixarene-Dispersed Resin Particles D) To 1.4 kg of a polyester resin A was added 0.6 parts of p-tert-butylcalix (8) arene as a charge control agent.
Add kg and mix for 3 minutes with 9 l Henschel mixer. This mixture was kneaded with a twin-screw extruder kneaded at 120 ° C., and then mixed with three rolls heated at 120 ° C.
After kneading for 5 minutes and cooling, the mixture was coarsely pulverized with a feather mill to obtain calixarene-dispersed resin particles D having a calixarene content of 30% by weight. The calixarene compound in the calixarene-dispersed resin particles D has an average particle diameter of 3 μm and a major axis of 8 μm
It was below.

(Production of Calixarene dispersed resin particles E) 0.6 kg of p-tert-octylcalix (8) arene (equivalent circular diameter of 2 to 60 μm) was added as a charge control agent to 1.4 kg of styrene-acrylic resin A. 9l
Mix for 3 minutes with Henschel mixer. This mixture is
5 kg / m ² with a heating / pressing kneader heated to 10 ° C
The mixture was kneaded under pressure for 1 hour, cooled, and coarsely pulverized with a feather mill to obtain calixarene-dispersed resin particles E having a calixarene content of 30% by weight. The calixarene compound in the calixarene-dispersed resin particles E has an average particle size of 2 μm.
m, and the major axis was 10 μm or less.

(Production of calixarene dispersed resin particles F) p-tert-octylcalix (8) arene was added to 1.4 kg of polyester resin A as a charge control agent.
Add 6 kg and mix for 3 minutes with 9 l Henschel mixer. This mixture was heated and pressurized to a temperature of 105 ° C.
Knead under pressure of 4 kg / m ² for 1 hour with a durer, and after cooling,
After coarse pulverization with a feather mill, calixarene content 30
By weight, calixarene-dispersed resin particles F were obtained. The calixarene compound in the calixarene-dispersed resin particles F had an average particle diameter of 2 μm and a major axis of 9 μm or less.

(Production of calixarene dispersed resin particles G) To 1.4 kg of styrene-acrylic resin A, 0.6 kg of p-tert-octylcalix (8) arene was added as a charge control agent, and mixed with a 9 l Henschel mixer for 3 minutes. I do. This mixture was kneaded with a twin screw extruder kneaded at 130 ° C., kneaded with three rolls heated at 130 ° C. for 10 minutes, cooled, coarsely pulverized with a feather mill, and calixarene content 30 By weight, calixarene dispersed resin particles G were obtained. The calixarene compound in the calixarene-dispersed resin particles G has an average particle size of 1.8 μm,
The major axis was 7 μm or less.

(Production of calixarene dispersed resin particles H) p-tert-octylcalix (8) arene was added to 1.4 kg of polyester resin A as a charge control agent.
Add 6 kg and mix for 3 minutes with 9 l Henschel mixer. This mixture was kneaded with a twin-screw extruder kneader heated to 110 ° C., and then mixed with three rolls heated to 110 ° C.
After kneading for minutes, the mixture was cooled and coarsely pulverized with a feather mill to obtain calixarene-dispersed resin particles H having a calixarene content of 30% by weight. The calixarene compound in the calixarene-dispersed resin particles H has an average particle diameter of 2 μm and a major axis of 7 μm
It was below.

(Example 1) 93 parts by weight of styrene-acrylic resin A 10 parts by weight of calixarene-dispersed resin particles A 3 parts by weight of carmine 6B (CI Pigment Red 57: 1) After kneading with a twin-screw extruder heated to 110 ° C., the mixture was cooled, and the kneaded material was roughly pulverized and further finely pulverized by a jet mill. Subsequently, classification was performed by a DS classifier to obtain toner particles having an average particle size of 8 μm.

The average particle size of the calixarene compound in the toner particles is 0.35 μm, the number ratio of particles of 2 μm or more is 0.05%, and the number ratio of particles of 1 μm or less is 98%. The shape was indistinguishable.

Silica fine particles (R972, manufactured by Nippon Aerosil Co., Ltd.) based on 100 parts by weight of the obtained toner particles.
0.3 parts by weight and 0.3 parts by weight of titanium dioxide fine particles (P25: manufactured by Nippon Aerosil Co., Ltd.) were added and mixed to obtain magenta toner. After adding this magenta toner to an acrylic resin-coated ferrite carrier (average particle size: 45 μm: manufactured by Powder Tech) so as to have a toner mixing ratio of 4% by weight, the toner mixing ratio was further 8% by weight. And stirred and mixed for 1 minute. The measured amount of charge of the developer was 18 μc / g. When the developer was placed on the magnet roller and the roller was rotated without applying an electric field, the toner scattering amount was 6.25%.

The toner and the carrier are mixed, and the toner is mixed.
A developer having a mixing ratio of 8% by weight was prepared and subjected to a printing durability test of 10,000 sheets using a full-color copying machine (CF-70: manufactured by Minolta Camera Co., Ltd.).
A clear copied image without fog was obtained after printing for 10,000 sheets.

(Example 2) 93 parts by weight of a polyester resin A 10 parts by weight of calixarene-dispersed resin particles B 3 parts by weight of carmine 6B (CI Pigment Red 57: 1) In the same manner as in Example 1, magenta toner having an average particle size of 8 μm was produced.

The calixarene compound in the toner particles has an average particle size of 0.6 μm, the number ratio of particles of 2 μm or more is 0.01%, and the number ratio of particles of 1 μm or less is 99%. The shape was indistinguishable.

When this toner was evaluated in the same manner as in Example 1, the charge amount was 20 μc / g and the toner scattered amount was 5 μc / g.
%, And a clear copy image free from fog was obtained in the initial and after 10,000 sheets of printing in the printing durability test.

(Example 3) 93 parts by weight of styrene-acrylic resin A 10 parts by weight of calixarene-dispersed resin particles C 3 parts by weight of carmine 6B (CI Pigment Red 57: 1) Except for using the above materials A magenta toner having an average particle size of 8 μm was produced in the same manner as in Example 1.

The average particle size of the calixarene compound in the toner particles is 0.45 μm, the number ratio of particles of 2 μm or more is 0.1%, and the number ratio of particles of 1 μm or less is 97%. The shape was indistinguishable.

The toner was evaluated in the same manner as in Example 1. As a result, the charge amount was 17.5 μc / g and the toner scattering amount was 6%. A clear copy image without fog was obtained.

(Example 4) 93 parts by weight of a polyester resin A 10 parts by weight of calixarene-dispersed resin particles D 3 parts by weight of carmine 6B (CI Pigment Red 57: 1) In the same manner as in Example 1, magenta toner having an average particle size of 8 μm was produced.

The average particle size of the calixarene compound in the toner particles is 0.25 μm, the number ratio of particles of 2 μm or more is 0.01%, and the number ratio of particles of 1 μm or less is 99%. The shape was indistinguishable.

When the toner was evaluated in the same manner as in Example 1, the charge amount was 18 μc / g and the toner scattered amount was 5 μc / g.
%, And a clear copy image free from fog was obtained in the initial and after 10,000 sheets of printing in the printing durability test.

(Example 5) 90.7 parts by weight of styrene-acrylic resin A 13.3 parts by weight of calixarene-dispersed resin particles E 3 parts by weight of carmine FB (CI Pigment Red 5) A magenta toner having an average particle size of 8 μm was produced in the same manner as in Example 1 except for the above.

The average particle size of the calixarene compound in the toner particles is 0.3 μm, the number ratio of particles of 2 μm or more is 0.05%, and the number ratio of particles of 1 μm or less is 99%. The shape was indistinguishable.

Silica fine particles (R972, manufactured by Nippon Aerosil Co., Ltd.) based on 100 parts by weight of the obtained toner particles.
0.5 part by weight was added and mixed to obtain magenta toner.

When this toner was evaluated in the same manner as in Example 1, the charge amount was 22 μc / g and the toner scattering amount was 6
%, And a clear copy image free from fog was obtained in the initial and after 10,000 sheets of printing in the printing durability test.

(Example 6) 90.7 parts by weight of polyester resin A 13.3 parts by weight of calixarene-dispersed resin particles F 3 parts by weight of carmine FB (CI Pigment Red 5) Except for using the above materials Magenta toner having an average particle size of 8 μm was produced in the same manner as in Example 5.

The calixarene compound in the toner particles has an average particle size of 0.35 μm, the number ratio of particles of 2 μm or more is 0.01%, and the number ratio of particles of 1 μm or less is 99%. The shape was indistinguishable.

When this toner was evaluated in the same manner as in Example 1, the charge amount was 24 μc / g and the toner scattered amount was 4 μc / g.
%, And a clear copy image free from fog was obtained in the initial and after 10,000 sheets of printing in the printing durability test.

(Example 7) 90.7 parts by weight of styrene-acrylic resin A 13.3 parts by weight of calixarene-dispersed resin particles G 3 parts by weight of carmine FB (CI Pigment Red 5) The above materials are used. A magenta toner having an average particle size of 8 μm was produced in the same manner as in Example 5 except for the above.

The calixarene compound in the toner particles has an average particle size of 0.7 μm, the number ratio of particles of 2 μm or more is 0.1%, and the number ratio of particles of 1 μm or less is 97%. The shape was indistinguishable.

When this toner was evaluated in the same manner as in Example 1, the charge amount was 21 μc / g, and the toner scattering amount was 6
%, And a clear copy image free from fog was obtained in the initial and after 10,000 sheets of printing in the printing durability test.

(Example 8) 90.7 parts by weight of styrene-acrylic resin A 13.3 parts by weight of calixarene-dispersed resin particles H 3 parts by weight of carmine FB (CI Pigment Red 5) The above materials are used. A magenta toner having an average particle size of 8 μm was produced in the same manner as in Example 5 except for the above.

The calixarene compound in the toner particles has an average particle size of 0.3 μm, the number ratio of particles of 2 μm or more is 0.01%, and the number ratio of particles of 1 μm or less is 99%. The shape was indistinguishable.

The toner was evaluated in the same manner as in Example 1. As a result, the charge amount was 22.5 μc / g and the toner scattering amount was 4.5%. A clear copied image without fog was obtained after printing.

(Comparative Example 1) 100 parts by weight of styrene-acrylic resin A 3 parts by weight of p-tert-butylcalix (8) arene (equivalent circular diameter of 2-80 μm) Carmine 6B (CI Pigment Red 57: 1) 3 parts by weight The above materials were mixed well with a Henschel mixer,
The mixture was kneaded with a heated twin screw extruder, cooled, and the kneaded material was coarsely pulverized and further finely pulverized with a jet mill.

Then, the particles were classified with a DS classifier to obtain an average particle size of 8 μm.
m magenta toner particles were obtained.

The calixarene compound in the toner particles has an average particle size of 1.3 μm, the number ratio of particles of 2 μm or more is 12%, and the number ratio of particles of 1 μm or less is 15%.
Many columnar particles were also present.

Silica fine particles (R972, manufactured by Nippon Aerosil Co., Ltd.) based on 100 parts by weight of the obtained toner particles.
0.3 parts by weight and 0.3 parts by weight of titanium dioxide fine particles (P25: manufactured by Nippon Aerosil Co., Ltd.) were added and mixed to obtain magenta toner.

The toner was evaluated in the same manner as in Example 1. As a result, the charge amount was 14 μc / g and the toner scattering amount was 1
The fog was 2.5%, and fog occurred from the beginning in the printing durability test. The amount of fog increased as the number of printings increased.

(Comparative Example 2) 100 parts by weight of polyester resin A 3 parts by weight of p-tert-butylcalix (8) arene 3 parts by weight of carmine 6B (CI Pigment Red 57: 1) A magenta toner having an average particle size of 8 μm was produced in the same manner as in Comparative Example 1 except that the heating temperature of the kneader was changed to 130 ° C.

The calixarene compound in the toner particles has an average particle size of 2.1 μm, the number ratio of particles of 2 μm or more is 44%, the number ratio of particles of 1 μm or less is 7%, and a large number of columnar particles are present. Was.

When this toner was evaluated in the same manner as in Example 1, the charge amount was 15 μc / g and the toner scatter amount was 1
The fog was 2%, and fog occurred from the beginning in the printing durability test. The amount of fogging increased as the number of printings increased.

(Comparative Example 3) 100 parts by weight of styrene-acrylic resin A 4 parts by weight of p-tert-octyl calix (8) arene (equivalent circular diameter 2 to 60 μm) Carmine FB (CI Pigment Red 5) 3 parts by weight A magenta toner having an average particle size of 8 μm was produced in the same manner as in Comparative Example 1 except that the above-mentioned materials were used and the heating temperature of the kneader was changed to 130 ° C.

The calixarene compound in the toner particles has an average particle size of 0.95 μm, the number ratio of particles of 2 μm or more is 2%, and the number ratio of particles of 1 μm or less is 63%.
Columnar particles were also present.

When this toner was evaluated in the same manner as in Example 1, the charge amount was 16 μc / g, and the toner scattered amount was 1
In the printing durability test, a good image was obtained without fogging at the initial stage, but fogging occurred after about 4000 printings.

(Comparative Example 4) 100 parts by weight of polyester resin A 4 parts by weight of p-tert-octyl calix (8) arene 3 parts by weight of carmine FB (CI Pigment Red 5) Kneading using the above materials A magenta toner having an average particle size of 8 µm was produced in the same manner as in Comparative Example 1 except that the heating temperature of the machine was changed to 110 ° C.

The average particle size of the calixarene compound in the toner particles is 1.0 μm, the number ratio of particles of 2 μm or more is 3%, the number ratio of particles of 1 μm or less is 60%, and some of the columnar particles are also formed. Existed.

The toner was evaluated in the same manner as in Example 1. As a result, the charge amount was 15 μc / g, and the toner scattering amount was 1
0%, and a good image was obtained without fog in the initial stage of the printing durability test, but fog occurred around 4000 printing presses.

[0103]

According to the present invention, it is possible to provide a toner which has uniform charging performance, does not generate toner fog, and has excellent environmental stability and safety.

Further, according to the present invention, it is possible to provide a color toner excellent in color tone and capable of reproducing an excellent image without fog or the like.

Further, according to the present invention, it is possible to provide a toner which does not generate spent on a carrier and has excellent durability.

[0106]

──────────────────────────────────────────────────続 き Continuing on the front page (72) Katsunori Kurose 2-3-13 Azuchicho, Chuo-ku, Osaka-shi Osaka International Building Minolta Camera Co., Ltd. (72) Hiroyuki Fukuda 2-chome Azuchicho, Chuo-ku, Osaka-shi No. 3-13 Osaka International Building Minolta Camera Co., Ltd. Examiner Kanae Isogai (56) References JP-A-2-201378 (JP, A) JP-A-2-161469 (JP, A) (58) (Int.Cl. ⁷ , DB name) G03G 9/08

Claims (1)

(57) [Claims] 1. A toner in which at least a colorant and a charge control agent are dispersed in a binder resin, wherein the charge control agent is a calixarene compound, and the average particle size of the calixarene compound dispersed in the toner. Diameter is 1.0
A toner for developing an electrostatic latent image, characterized in that the content of a calixarene compound having a particle size of at most 2.0 μm and at least 2.0 μm is at most 1%.