JPH07225495A - Toner for developing electrostatic charge image - Google Patents

Abstract

PURPOSE:To ensure satisfactory transfer efficiency and superior environmental stability by incorporating a bonding resin and a polymer having a urea deriv. as partial structural units. CONSTITUTION:A bonding resin and a polymer having a urea deriv. as partial structural units are incorporated. A polymer having a deriv. obtd. by introducing an aryl group to a nitrogen atom of urea is preferably used as the polymer from the viewpoint of triboelectric chargeability and easiness of synthesis. In this case, a substituent introduced to the aryl group is not especially limited but halogen, sulfonic acid, carboxylic acid, carbonyl, alkyl, alkoxy or aralkyl which may have a substituent, especially fluorine, fluorine substd. alkyl, sulfonic acid, carboxylic acid or carbonyl is preferably used from the viewpoint of chargeability, safety and easiness of production. The polymer having a urea deriv. as partial structural units is preferably the polymer having >=3 partial structural units of the urea deriv. as repeating units.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge image developing toner for developing an electrostatic charge image in an image forming method such as electrophotography and electrostatic recording.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic method, U.S. Pat. No. 2,297,691 and JP-B-42-23910 are known.
Various methods are described in, for example, Japanese Patent Publication No. 43-24748.

The developing methods applied to these electrophotographic methods and the like are roughly classified into a dry developing method and a wet developing method. The former is further divided into a method using a two-component developer and a method using a one-component developer.

As the toner applied to these dry developing methods, fine powder in which a dye or a pigment is dispersed in a natural or synthetic resin has been conventionally used. For example, 1 to 3 in which a colorant is dispersed in a binder resin such as polystyrene is used.
Particles finely pulverized to about 0 μm are used as a toner. A magnetic toner containing magnetic particles such as magnetite is used. In the case of a system using a two-component developer, the toner is usually used by mixing it with carrier particles such as glass beads, iron powder and ferrite particles.

Any toner must have a positive or negative charge, depending on the polarity of the electrostatic latent image being developed.

To retain the electric charge in the toner, it is possible to utilize the triboelectric chargeability of the resin which is a component of the toner, but in this case, the toner chargeability is low, so the toner image obtained by development is fogged. It is easy to get blurred. Therefore, in order to impart an appropriate triboelectric chargeability to the toner, a dye, a pigment or a charge control agent which imparts the chargeability is added.

Charge control agents known in the art today include metal complex salts of monoazo dyes, salicylic acid,
Known are metal complex salts of naphthoic acid and dicarboxylic acid, copper phthalocyanine pigments and the like.

Since some of these charge control agents easily contaminate the sleeve or carrier, the toner using them has a reduced triboelectric charge amount as the number of copies increases.
Causes a decrease in image density. Further, when the triboelectric charge amount of the charge control agent is low, it is likely to be affected by temperature and humidity, so that the environmental density of the image density is easily changed, and when the storage stability is poor, the triboelectric chargeability is likely to decrease during long-term storage. . Further, if the dispersibility of the charge control agent in the resin is poor, the toner using the charge control agent is not uniform in the triboelectric charge amount between toner particles, and the fog phenomenon easily occurs, and the thermal stability of the charge control agent is poor. However, it may be decomposed and deteriorated during the heating and kneading process during toner production. The toner produced by reusing a part of the toner containing such a charge control agent is apt to generate reversely charged particles and easily cause fogging. Further, when the charge control agent is colored, it is difficult to use it for color toner.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel toner for developing an electrostatic charge image, which solves the above problems.

An object of the present invention is to provide a toner for developing an electrostatic charge image which has good transfer efficiency.

An object of the present invention is to provide a toner for developing an electrostatic charge image, which has little deterioration in image quality and has good durability and stability.

An object of the present invention is to provide a toner for developing an electrostatic charge image, which has good dispersibility of a charge control agent.

An object of the present invention is to provide a toner for developing an electrostatic charge image capable of forming a smooth high quality color image of a halftone image.

[0014]

The present invention relates to an electrostatic charge image developing toner containing a binder resin and a polymer having a urea derivative as a partial structural unit.

Among them, a polymer having a derivative in which an aryl group is introduced into the nitrogen atom of urea is preferable from the viewpoints of triboelectric charging property and easiness of synthesis. The substituent to be introduced into the aryl group is not particularly limited, but has a halogen atom, a sulfonic acid group, a carboxylic acid group, a carbonyl group, an alkyl group, an alkoxy group, a phenyl group which may have a substituent, or a substituent. Aralkyl group which may be, particularly, fluorine atom, fluorine-substituted alkyl group, sulfonic acid group, carboxylic acid group,
A carbonyl group or the like is generally preferred from the viewpoints of chargeability, safety, easiness of production and the like.

The polymer having a urea derivative as a partial structure is preferably a polymer having three or more urea derivative partial structures as repeating units. The urea derivative means one in which at least one of hydrogen bonded to the nitrogen atom of urea is replaced with an organic group. Further, a polymer having a urea derivative as a partial structure means a polymer having a urea derivative in the main chain or a side chain, but in order to exhibit the excellent charging characteristics of the urea derivative, the urea derivative is in the side chain. It is preferably pendant. Further, a copolymer having a partial structure of a urea derivative as a repeating unit is also included in the polymer of the present invention.

Although it is not known to use the urea polymer of the present invention as a charge control agent, it is disclosed in JP-B-48-267 that a compound having a urea bond is contained in the toner.
No. 84 publication. Japanese Examined Japanese Patent Publication 48-26784
In the publication, in order to improve the fixing property, a urea derivative obtained by reacting an isocyanate having a long-chain alkyl group with a dye having an amino group is used, and it has positive chargeability from the content of the examples. I understand.

The present inventors have made a study by paying attention to the good triboelectric chargeability of the urea derivative. As a result, they have found that polymerizing the urea derivative provides good triboelectric chargeability. Although the charging speed and the triboelectric charge amount are slightly inferior to the monomer of the urea derivative, the thermal stability is improved as compared with the monomer. The thermal stability of the urea-based monomer does not pose a problem in normal use, but in order to improve the dispersion state of the other raw materials in the resin, when the load is increased during the kneading process in the toner production, it is accompanied by it. It was found that a part of the urea derivative is decomposed by the heat generation, which may adversely affect the toner characteristics. It was newly found that such degradation can be improved by polymerizing. Particularly in the case of color toners, it is required to improve the dispersibility of the colorant in the binder resin in order to improve the coloring power and transparency of the toner. In such a case, the thermal stability of the urea derivative polymer used in the present invention exhibits very excellent characteristics during melt kneading.

Further, the toner containing the urea derivative polymer of the present invention has a better transferability of the toner from the photoconductor to the transfer material such as paper than the ordinary toner. for that reason,
The toner utilization efficiency is improved. Further, deterioration of image quality due to toner scattering in the transfer process is remarkably improved.

The reason why the transferability of the toner is improved is not clear, but it is considered that the urea derivative polymer has a releasing effect. This effect is particularly remarkable in the case of a urea derivative polymer having fluorine or a fluorine-substituted alkyl group as a substituent. This seems to be due to the releasing property of fluorine. Further, it is presumed that the polymer having a urea derivative as a partial structure has an effect of suppressing excessive charging of the toner, the mirroring force between the toner and the photoconductor is in an appropriate range, and improves the transfer efficiency of the toner. .

Specific examples of the urea derivative polymer that can be used in the toner of the present invention are shown below, but these are representative examples in consideration of easy handling.

[0022]

[Outer 1]

[0023]

[Outside 2]

Polymers of urea derivatives can be synthesized by various methods.

For example, it can be obtained by reacting a polymer of an aniline derivative and an isocyanate derivative with dioxane as a solvent.

The reaction product of polymethylene polyphenyl polyisocyanate (n = 3 to 5) of urea derivative polymer (1) and m-trifluoromethylaniline is reacted with dioxane at 45 ° C. for 2 hours and further reacted. Temperature 85
It can be obtained by raising the temperature to ℃ and reacting for 1 hour.

It was a white powder and had a melting point of 300 ° C. or higher.

The reaction product of polymethylene polyphenyl polyisocyanate (n = 3 to 5) of urea derivative polymer (2) and p-fluoroaniline can be obtained by the same reaction as that of urea derivative polymer (1).

It was a white powder and had a melting point of 300 ° C. or higher.

As a method of incorporating the polymer of the urea derivative into the toner, there are a method of adding it inside the toner particles and a method of adding it externally. The amount of these urea derivative polymers used is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is uniquely limited. When not internally added, it is preferably used in an amount of 0.1 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the binder resin. When externally added, the resin 100
It is preferably 0.01 to 5 parts by weight with respect to parts by weight. In the case of external addition, it is preferable to fix or bury the toner particles having the binder resin and the colorant in the vicinity of the surface thereof by mechanical impact.

The urea derivative polymer can also be used in combination with a conventionally known charge control agent.

In the toner of the present invention, it is preferable to use an inorganic oxide fine powder externally added to the toner. As the inorganic oxide fine powder, various powders can be used, but those having a metal ion electronegativity of 10 to 15 are preferable from the viewpoints of charging speed and environmental stability. Examples of such inorganic oxides include titanium oxide and aluminum oxide.

The above inorganic oxide may be treated with an organic silicon compound such as a silane coupling agent or silicone oil for the purpose of hydrophobizing, etc.

The coloring agents used in the present invention include carbon black, lamp black, ultramarine, nigrosine dye, aniline blue, phthalocyanine blue, phthalocyanine green, Hansa yellow G, rhodamine 6G,
Calco oil blue, chrome yellow, quinacridone,
Conventionally known dyes and pigments such as benzidine yellow, rose bengal, triarylmethane dyes, monoazo dyes and disazo dyes may be used alone or in combination.

The binder resin used in the present invention is, for example, a homopolymer of styrene such as polystyrene, poly-p-chlorostyrene, or polyvinyltoluene or a substitution product thereof; a styrene-p-chlorostyrene copolymer, Styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic acid ester copolymer,
Styrene-methacrylic acid ester copolymer, styrene-
α-Chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer Styrene-based copolymers such as styrene-isoprene copolymer and styrene-acrylonitrile-indene copolymer; polyvinyl chloride, phenol resin, natural modified phenol resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, poly Vinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin and the like can be used.

A crosslinked styrene copolymer is also a preferred binder resin.

Examples of the comonomer for the styrene monomer of the styrene copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate,
Double bond such as dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide, etc. A dicarboxylic acid having a double bond such as maleic acid, butyl maleate, methyl maleate and dimethyl maleate, and a substituted product thereof; eg, vinyl chloride, vinyl acetate, vinyl benzoate Vinyl esters such as ethylene, propylene, butylene, etc .; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone; vinyl vinyl ether, vinyl ethyl ether, etc. Le, vinyl ethers such as vinyl isobutyl ether; vinyl monomers are used alone or two or more.

Here, as the cross-linking agent, a monomer having two or more polymerizable double bonds is mainly used, and examples thereof include aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; for example, ethylene glycol diacrylate. Ethylene glycol dimethacrylate, 1,3
-A double bond such as butanediol dimethacrylate
Carboxylic acid ester having one; a divinyl compound such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone; and a monomer having three or more vinyl groups. These are used alone or as a mixture.

In particular, the molecular weight distribution measured by gel permeation chromatogram (GPC) shows a molecular weight of 3 ×.
A styrene-based copolymer having at least one peak (maximum value) in the region of 10 ^{3 to} 5 × 10 ⁴ and having at least one peak or shoulder in the region of molecular weight of 10 ⁵ or more is preferable from the viewpoint of fixability.

The molecular weight distribution by GPC is measured under the following conditions.

The column was stabilized in a heat chamber at 40 ° C. and THF was added as a solvent to the column at this temperature.
At a flow rate of 1 ml per minute, and 100 μl of a sample solution dissolved in THF is injected for measurement. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value and the count number of a calibration curve prepared using several kinds of monodisperse polystyrene standard samples. As the standard polystyrene sample for preparing the calibration curve, for example, a standard polystyrene sample having a molecular weight of about 10 ² to 10 ⁷ manufactured by Tosoh or Showa Denko is used, and it is suitable to use a standard polystyrene sample of at least about 10 points. . An RI (refractive index) detector is used as the detector. As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns. For example, Shodex GPC KF-801, 8 manufactured by Showa Denko KK
02, 803, 804, 805, 806, 807, 80
Combination of 0P and TSKgel G1 made by Tosoh Corporation
000H (H _XL ), G2000H (H _XL ), G3000
H (H _XL ), G4000H (H _XL ), G5000H (H
_XL ), G6000H (H _XL ), G7000H (H _XL ),
A combination of TSKguard columns can be mentioned.

The sample is prepared as follows.

The sample was placed in THF, left for several hours, and shaken thoroughly until the samples did not coalesce.
Mix well with F and let stand for 12 more hours. At this time, the leaving time in THF should be 24 hours or more. Then, a sample processing filter (pore size 0.
45 to 0.5 μm, for example, Mysholydisc H-25
-5 manufactured by Tosoh Co., Ltd., available from Ekikurodisc 25CR Gelman Science Japan Co., Ltd.) can be used as a GPC sample. The sample concentration is
The resin component is adjusted to 0.5 to 5 mg / ml.

In the present invention, polyester resin is also preferable as the binder resin.

As the alcohol component constituting the polyester resin, ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol,
Triethylene glycol, 1,5-pentanediol,
1,6-hexanediol, neopentyl glycol,
2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, and a bisphenol derivative represented by the formula (A);

[0046]

[Outside 3] (In the formula, R is an ethylene or propylene group, and X, Y
Are each an integer of 1 or more, and the average value of X + Y is 2 to 10. ) And other diols, and glycerin, sorbit, sorbitan, and other polyhydric alcohols.

As the acid component, a divalent carboxylic acid,
Benzenedicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid and phthalic anhydride or anhydrides thereof; alkyldicarboxylic acids such as succinic acid, adipic acid, sebacic acid and azelaic acid or anhydrides thereof; and further having 6 to 18 carbon atoms Succinic acid or its anhydride substituted with an alkyl group; fumaric acid, maleic acid, citraconic acid,
Examples thereof include unsaturated dicarboxylic acids such as itaconic acid and anhydrides thereof, and examples of trivalent or higher carboxylic acids include trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid and anhydrides thereof.

The preferred alcohol component is the bisphenol derivative of the above formula (A), and the acid component is phthalic acid, terephthalic acid, isophthalic acid, or its anhydride, succinic acid, n-dodecenylsuccinic acid or its anhydride, Examples thereof include dicarboxylic acids such as fumaric acid, maleic acid and maleic anhydride, and tricarboxylic acids such as trimellitic acid and its anhydride.

The acid value of the resin used in the present invention is preferably such that the acid value of the toner is in the range of 5 mgKOH / g to 40 mgKOH / g. The acid component of the resin has a negative triboelectric chargeability, but the resin having an acid component amount corresponding to the acid value of the toner falls within this range. A resin having the urea derivative of the present invention as a partial structure has a triboelectrification characteristic charging rate. And the amount of charge is appropriately complemented. When the amount of acid component increases to more than 40 mgKOH / g, the adsorption of water due to the acid component causes
Rather, the triboelectric charge amount decreases.

In the present invention, the acid value is measured by JI.
The method of SK-0070 can be applied. The acid value is m of potassium hydroxide required to neutralize 1 g of toner.
Expressed in g. However, when the toner contains a magnetic material, the residue obtained by eluting the magnetic material with an acid is 1 g of toner.

When the pressure-fixing system is used, a binder resin for pressure-fixing toner can be used, and examples thereof include polyethylene, polypropylene, polymethylene, polyurethane elastomer, ethylene-ethyl acrylate copolymer,
Examples thereof include ethylene-vinyl acetate copolymers, ionomer resins, styrene-butadiene copolymers, styrene-isoprene copolymers, linear saturated polyesters and paraffins.

The electrostatic image developing toner of the present invention can also be used as a magnetic toner by incorporating a magnetic material. Magnetic materials used include magnetite and γ-
Iron oxides such as iron oxides, ferrites, and iron-rich ferrites;
Metals such as iron, cobalt and nickel, or these metals and metals such as aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten and vanadium. And alloys thereof and mixtures thereof.

These magnetic materials have an average particle size of 0.1 to 1
μm, preferably about 0.1 to 0.5 μm.

The amount contained in the toner preferably satisfies the following formula.

MT =-(10/3) r + (70 ± 15), r ≦ 9, where MT (%) is the amount of magnetic material in the toner and r (μm) is the weight average particle size of the toner. in the magnetic toner containing the urea derivative polymers of the present invention, 20~50Am ² / k the saturation magnetization of the magnetic toner
It has been found that the change in particle size of the magnetic toner in the developing device due to the increase in the number of copies can be remarkably suppressed by setting g.
As a result, the deterioration of the image quality and the decrease of the image density with the increase in the number of copies are remarkably improved as compared with the normal magnetic toner. As the magnetic force of the magnetic toner, a vibrating sample magnetometer (VSM) BHU-30 manufactured by Riken Denshi Co., Ltd. is used. Saturation magnetization (in the case of the present application, a value at 1 kilo Oersted) is obtained from a hysteresis curve when a magnetic field is swept up to 1 kilo Oersted in a magnetic toner formed into a pellet having a diameter of 5 mm.

Further, the toner of the present invention can be mixed with a carrier and used as a two-component developer. As the carrier that can be used in the present invention, known carriers can be used. For example, iron powder, ferrite powder, powder having magnetism such as nickel powder, glass beads and the like, and those whose surface is treated with resin or the like can be mentioned. Further, as the resin for coating the carrier surface, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, acrylic acid ester copolymer, methacrylic acid ester copolymer, silicone resin, fluorine-containing resin, Examples thereof include polyamide resin, ionomer resin, polyphenylene sulfide resin, and the like. These can be used alone or in combination.

The toner of the present invention has a weight average particle diameter of 3 to 1.
It is preferably 5 μm. In particular, 12 to 60% by number of toner particles having a particle size of 5 μm or less are contained, and
1 to 33% by number of toner particles having a particle size of 12.7 μm are contained, 2.0% by weight or less of toner particles having a particle size of 16 μm or more are contained, and the toner has a weight average particle size of 4
From the standpoint of development characteristics, it is more preferably 10 μm.

The particle size distribution of the toner can be measured by various methods, but in the present invention, it is suitable to use a Coulter counter.

As a measuring device, a Coulter counter T
Using A-II type (manufactured by Coulter), an interface (manufactured by Nikkaki) and C for outputting number distribution and volume distribution
An X-1 personal computer (Canon) is connected, and the electrolyte is approximately 1% Na using primary sodium chloride.
Adjust the Cl aqueous solution. For example,

[0060]

[Outside 4] (Manufactured by Coulter Scientific Japan) can be used. As a measuring method, the electrolytic aqueous solution is 100 to 15
To 0 ml, 0.1 to 5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant, and 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the volume and the number of toner particles are measured by the Coulter Counter TA-II type using an aperture of 100 μm as an aperture. Then, the volume distribution and the number distribution of the toner particles of 2 to 40 μm are calculated. Then, the weight-based weight average diameter (D4) obtained from the volume distribution of the toner particles
(The median value of each channel is set as a representative value for each channel), and the weight-based coarse powder amount calculated from the volume distribution (20.2
The number of fine particles on the basis of the number (6.35 μm or less) determined from the number distribution was determined.

The toner of the present invention may be mixed with an additive if necessary. Examples of the additives include lubricants such as zinc stearate; abrasives such as cerium oxide and silicon carbide; fluidity imparting agents such as aluminum oxide; anti-caking agents; conductivity imparting agents such as carbon black and tin oxide.

Fluorine-containing polymer fine powders such as polyvinylidene fluoride fine powders are also preferable additives from the viewpoints of fluidity, abradability and charge stability.

For the purpose of improving releasability at the time of heat roll fixing, wax-like substances such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, carnauba wax, sazol wax and paraffin wax are added in an amount of 0.5-5. It is also one of the preferred embodiments of the present invention to add about wt% to the toner. In particular, Sazol wax is one of the preferable release agents.

In producing the toner of the present invention,
After thoroughly mixing the toner constituent materials as described above with a ball mill or other mixer, they are well kneaded with a heat kneader such as a heat roll kneader or an extruder, and after cooling and solidification,
A method of obtaining a toner by mechanical pulverization and classification is preferable. Alternatively, after dispersing the constituent materials in the binder resin solution,
A method of obtaining a toner by spray-drying; or a so-called microcapsule toner composed of a core material and a shell material, a method of incorporating a predetermined material into the core material or the shell material, or both of them, can be applied.

Further, a method of producing a polymerized toner in which a predetermined material is mixed with a monomer which constitutes a binder resin to form an emulsified suspension and then polymerized to obtain a toner can be used.

Further, if desired, desired additives can be thoroughly mixed with a mixer such as a Henschel mixer to produce the toner of the present invention.

The toner of the present invention can be used by conventional means for development for developing an electrostatic charge image in electrophotography, electrostatic recording, electrostatic printing and the like.

The urea derivative polymer is colorless or light-colored, is extremely stable thermally and mechanically, and has a good negative triboelectric charging property. Moreover, the transferability of the toner can be improved.

Therefore, the toner of the present invention is unlikely to cause image quality deterioration due to continuous copying, and can provide an image having excellent density uniformity. Further, when applied to color toner, it can provide a vivid color image. Further, since the triboelectrification property largely changes depending on the kind of the substituent, it can be applied to various developing methods.

[0070]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.
All parts in the following formulations are parts by weight.

Example 1 Styrene-butylmethacrylate-monobutylmalate copolymer (peak 1: molecular weight 10,000, peak 2:
Molecular weight 250,000) 100 parts Magnetic substance (average particle size: 0.2 μm) 80 parts Sazole wax 3 parts Urea derivative polymer (1) (n = 3 to 5) 2 parts

After thoroughly mixing the above materials with a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 130 ° C. The obtained kneaded product was cooled, coarsely pulverized, and finely pulverized using a fine pulverizer using a jet stream. Further, the finely pulverized product obtained was subjected to strict classification of ultrafine powder and coarse powder at the same time with a multi-division classifier (Elbow Jet classifier manufactured by Nittetsu Mining Co., Ltd.) utilizing the Coanda effect to give a weight average particle size of 8. 5 μm black fine powder (negatively chargeable magnetic toner) was obtained.

The saturation magnetization of this magnetic toner is 35 Am ² /
The acid value was 5 mgKOH / g.

To 100 parts of the obtained magnetic toner, 0.4 parts of hydrophobic treated silica fine powder (average particle size 15 nm) and hydrophobic treated titanium oxide fine powder (average particle size 25 nm, titanium ion electronegativity 13) 0 2 parts were mixed with a Henschel mixer to obtain a negatively chargeable one-component magnetic toner.

The obtained one-component magnetic toner was applied to a commercially available electrophotographic copying machine NP-6060 (manufactured by Canon Inc.).
A copy test of 20,000 sheets was carried out in an environment of a temperature of 23 ° C. and a relative humidity of 60%.

As a result, a clear image having an image density of 1.38 was obtained from the initial stage. The image after copying 20,000 sheets was also clear with a density of 1.42.

The transfer efficiency of the toner from the photosensitive member to the transfer paper was 94%, which was good.

A similar copying test was carried out in a low temperature and low humidity environment of 15 ° C. and a humidity of 10% and in a high temperature and high humidity environment of a temperature of 30 ° C. and a humidity of 80%. Good results were obtained as well as the results under the environment.

Example 2 0.6 part of hydrophobically treated silica (average particle size 15 nm) was mixed with the magnetic toner obtained in Example 1 by a Henschel mixer to obtain a one-component magnetic toner.

A copy test was conducted on the obtained one-component magnetic toner under the same conditions as in Example 1.

As a result, a clear image having an image density of 1.33 was obtained from the beginning. The image after copying 20,000 sheets was also clear with a density of 1.40.

The transfer efficiency of the toner from the photoconductor onto the transfer paper was as good as 91%.

When the same copying test was conducted under the environment of low temperature and low humidity and high temperature and high humidity, the same good result as the result under the environment of normal temperature and normal humidity was obtained.

Example 3 A magnetic toner having a weight average particle diameter of 8.5 μm was obtained in the same manner as in Example 1 except that the amount of the magnetic material in Example 1 was changed to 120 parts.

The saturation magnetization of this magnetic toner is 42 Am ² /
It was kg.

To 100 parts of the obtained magnetic toner, 0.4 part of hydrophobically treated silica (average particle size 15 nm) and 0.2 part of hydrophobically treated titanium oxide (average particle size 25 nm, titanium ion electronegativity 13) were added. Was mixed with a Henschel mixer to obtain a one-component magnetic toner.

The obtained one-component magnetic toner was applied to a commercially available electrophotographic copying machine NP-6060 (manufactured by Canon Inc.).
20,000 under environment of temperature 23 ℃ and relative humidity 60% RH
A zero copy test was performed.

As a result, a clear image having an image density of 1.35 was obtained from the beginning. The image after copying 20,000 sheets was also clear with a density of 1.31.

The transfer efficiency of the toner from the photoconductor onto the transfer paper was as good as 92%.

When the same copying test was conducted under the environment of low temperature and low humidity and high temperature and high humidity, the same good result as the result under the environment of normal temperature and normal humidity was obtained.

Comparative Example 1 Instead of 2 parts of the urea derivative polymer (1), a urea compound was used.

[0092]

[Outside 5] The weight average particle size is 8.
A magnetic toner of 5 μm was obtained.

The obtained magnetic toner was subjected to a copy test under the same conditions as in Example 1.

As a result, a clear image having an image density of 1.41 was obtained from the beginning. After copying 20,000 sheets, the density is 1.
38 images were obtained.

The transfer efficiency of the toner from the photoconductor onto the transfer paper was 82%, which was lower than the result of Example 1.

When the same copying test was conducted under the environment of low temperature and low humidity and high temperature and high humidity, the same result as the result under the environment of 23 ° C. and 60% was obtained.

Comparative Example 2 A weight average particle size of 8. was used as in Example 1 except that 2 parts of a styrene-methacrylate-methylpropane sulfonate copolymer was used instead of 2 parts of the urea derivative polymer (1). A magnetic toner of 5 μm was obtained.

The obtained magnetic toner was subjected to a copy test under the same conditions as in Example 1.

As a result, the initial image density was as low as 1.18. After copying 20,000 sheets, a clear image having a density of 1.32 was obtained.

The transfer efficiency of the toner from the photoconductor onto the transfer paper was 76%.

Similar copying tests were performed under the environment of low temperature and low humidity and high temperature and high humidity. Good results were obtained in an environment of low temperature and low humidity, but in an environment of high temperature and high humidity, the image density was 1.02 even after copying 20,000 sheets.

Example 4 Polyester A (Propylene oxide-modified bisphenol A / fumaric acid) 100 parts Carbon black 5 parts Urea derivative polymer (2) (n = 3 to 5) 4 parts

After thoroughly mixing the above materials with a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 130 ° C. The obtained kneaded product was cooled, coarsely pulverized, and finely pulverized using a fine pulverizer using a jet stream. Further, the finely pulverized product obtained was subjected to strict classification of ultrafine powder and coarse powder at the same time with a multi-division classifier (Elbow Jet classifier manufactured by Nittetsu Mining Co., Ltd.) utilizing the Coanda effect to give a weight average particle size of 8. 5 μm black fine powder (negatively chargeable black toner) was obtained.

The acid value of the obtained black fine powder is 10 mgKO.
It was H / g.

100 parts of the obtained black toner and hydrophobic titanium oxide fine powder (average particle size 25n
m) 0.8 part was mixed with a Henschel mixer to prepare a black toner to which hydrophobic titanium oxide was externally added.

Next, a black toner was mixed with a carrier in which ferrite particles having an average particle size of 65 μm were coated with a silicone resin to prepare a two-component developer. The mixing ratio is carrier 95
5 parts of black toner was used for each part.

This two-component developer was introduced into a commercially available color electrophotographic copying machine CLC-500 (manufactured by Canon Inc.) and a copying test was conducted.

When copying was performed in an environment of normal temperature and normal humidity (23 ° C., 60%), a good image having a density of 1.68 was obtained from the initial stage. The transfer efficiency of toner from the photoconductor to the transfer paper is 9
It was as good as 5%. Further, since the scattering of toner in the transfer process is remarkably improved, a very smooth halftone image and a sharp image can be obtained. Also, when copying 20,000 sheets, the density is 1.6
7 good images were obtained. No deterioration in image quality was observed with the increase in the number of copies. The transfer efficiency was 93%, showing no tendency to decrease.

Even under environmental conditions of low temperature and low humidity (15 ° C., 10%), a good image having a density of 1.65 was obtained from the initial stage. Two
When 10,000 sheets were copied, no decrease in image density was observed. In addition, the deterioration of the image quality such as the smoothness of the halftone image and the sharpness of the image with the increase in the number of copies was not observed.

Next, the same copying test was carried out under high temperature and high humidity (30 ° C., 80%) environmental conditions.
70 good images were obtained. After copying 20,000 sheets, the phenomenon of reduction in image density was not observed. Also,
No deterioration in image quality such as halftone image smoothness or image sharpness was observed with an increase in the number of copies.

Example 5 Polyester B (Propylene oxide-modified bisphenol A / fumaric acid) 100 parts Copper phthalocyanine 4 parts Urea derivative polymer (2) (n = 3 to 5) 3 parts

After thoroughly mixing the above materials with a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 130 ° C. The obtained kneaded product was cooled, coarsely pulverized, and finely pulverized using a fine pulverizer using a jet stream. Further, the finely pulverized product obtained was subjected to strict classification of ultrafine powder and coarse powder at the same time with a multi-division classifier (Elbow Jet classifier manufactured by Nittetsu Mining Co., Ltd.) utilizing the Coanda effect to give a weight average particle size of 8. 5 μm blue fine powder (negatively chargeable blue toner) was obtained.

The acid value of the obtained blue fine powder is 35 mgKO.
It was H / g.

To 100 parts of the obtained blue toner, hydrophobic titanium oxide fine powder (average particle size 25 n
m) 0.8 part was mixed with a Henschel mixer to prepare a blue toner to which hydrophobic titanium oxide was externally added.

Next, a carrier in which ferrite particles having an average particle diameter of 65 μm are coated with a silicone resin and a blue toner are mixed to obtain a two-component developer. The mixing ratio is carrier 95
5 parts of blue toner was used for each part.

This two-component developer was introduced into a commercially available color electrophotographic copying machine CLC-500 (manufactured by Canon Inc.) and a copying test was conducted.

When copying was performed in an environment of normal temperature and normal humidity, a good image having a density of 1.65 was obtained from the initial stage. The transfer efficiency of the toner from the photoconductor onto the transfer paper was as good as 96%. Further, since the scattering of toner in the transfer process is remarkably improved, a very smooth halftone image and a sharp image can be obtained. Also, 20,
After copying 000 sheets, a good image having a density of 1.67 was obtained. No deterioration in image quality was observed with the increase in the number of copies. The transfer efficiency was 95%, showing no tendency to decrease.

A good image with a density of 1.61 was obtained from the initial stage even under environmental conditions of low temperature and low humidity. After copying 20,000 sheets, the phenomenon of reduction in image density was not observed. In addition, the deterioration of the image quality such as the smoothness of the halftone image and the sharpness of the image with the increase in the number of copies was not observed.

Next, a similar copying test was carried out under high temperature and high humidity environmental conditions, and a good image having a density of 1.73 was obtained from the initial stage. After copying 20,000 sheets, the phenomenon of reduction in image density was not observed. In addition, the deterioration of the image quality such as the smoothness of the halftone image and the sharpness of the image with the increase in the number of copies was not observed.

Example 6 100 parts of the black toner of Example 4 and 0.6 part of hydrophobic silica fine powder (average particle size 15 nm) that has been hydrophobized are mixed by a Henschel mixer, and hydrophobic silica is externally added. A black toner that has been prepared is prepared.

Next, a black toner was mixed with a carrier in which ferrite particles having an average particle diameter of 65 μm were coated with a silicone resin to prepare a two-component developer. The mixing ratio is carrier 95
5 parts of black toner was used for each part.

A copy test was conducted on this two-component developer in the same manner as in Example 4.

When copying was performed in an environment of normal temperature and normal humidity, a good image having a density of 1.68 was obtained from the initial stage. The transfer efficiency of the toner from the photoconductor onto the transfer paper was as good as 92%. Further, since the scattering of toner in the transfer process is remarkably improved, a very smooth halftone image and a sharp image can be obtained. Also, 20,
After copying 000 sheets, a good image having a density of 1.61 was obtained. No deterioration in image quality was observed with the increase in the number of copies. The transfer efficiency was 90%, which was not a tendency to decrease.

Even under environmental conditions of low temperature and low humidity, a good image with a density of 1.61 was obtained from the beginning. When 20,000 sheets were copied, a good image having an image density of 1.57 was obtained. In addition, the deterioration of the image quality such as the smoothness of the halftone image and the sharpness of the image with the increase in the number of copies was not observed.

Next, a similar copying test was carried out under high temperature and high humidity environmental conditions, and a good image having a density of 1.75 was obtained from the initial stage. When 20,000 sheets were copied, a good image having an image density of 1.66 was obtained. In addition, the deterioration of the image quality such as the smoothness of the halftone image and the sharpness of the image with the increase in the number of copies was not observed.

Example 7 Polyester C (Propylene oxide-modified bisphenol A / fumaric acid) 100 parts Carbon black 5 parts Urea derivative polymer (2) (n = 3 to 50) 4 parts

After thoroughly mixing the above materials with a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 130 ° C. The obtained kneaded product was cooled, coarsely pulverized, and finely pulverized using a fine pulverizer using a jet stream. Further, the finely pulverized product obtained was subjected to strict classification of ultrafine powder and coarse powder at the same time with a multi-division classifier (Elbow Jet classifier manufactured by Nittetsu Mining Co., Ltd.) utilizing the Coanda effect to give a weight average particle size of 8. 5 μm black fine powder (negatively chargeable black toner) was obtained.

The acid value of the obtained black fine powder is 40 mgKO.
It was H / g.

100 parts of the obtained black toner and a hydrophobic titanium oxide fine powder which has been hydrophobized (average particle size: 25 n
m) 0.8 part was mixed with a Henschel mixer to prepare a black toner to which hydrophobic titanium oxide was externally added.

Next, a black toner was mixed with a carrier in which ferrite particles having an average particle diameter of 65 μm were coated with a silicone resin to prepare a two-component developer. The mixing ratio is carrier 95
5 parts of black toner was used for each part.

A copying test was conducted on this two-component developer in the same manner as in Example 4.

When copying was performed in an environment of normal temperature and normal humidity, a good image having a density of 1.85 was obtained from the initial stage. The transfer efficiency of the toner from the photoconductor to the transfer paper was as good as 95%. Further, since the scattering of toner in the transfer process is remarkably improved, a very smooth halftone image and a sharp image can be obtained. Also, 20,
After copying 000 sheets, a good image having a density of 1.84 was obtained. No deterioration in image quality was observed with the increase in the number of copies. The transfer efficiency was 92%, which was not a downward trend.

Even under environmental conditions of low temperature and low humidity, a good image with a density of 1.73 was obtained from the initial stage. After copying 20,000 sheets, the phenomenon of reduction in image density was not observed. In addition, the deterioration of the image quality such as the smoothness of the halftone image and the sharpness of the image with the increase in the number of copies was not observed.

Next, a similar copying test was carried out under high temperature and high humidity environmental conditions, and a good image having a density of 1.93 was obtained from the initial stage. However, as the copying was continued, some toner scattering occurred.

Example 8 Polyester A (Propylene oxide-modified bisphenol A / fumaric acid) 100 parts Carbon black 3.5 parts Urea derivative polymer (2) (n = 3 to 100) 4 parts

The above materials were mixed well in a blender. Two
The temperature of the axial kneading extruder was set to 110 ° C., and the kneading was carried out under a larger load than usual. The obtained kneaded product was cooled, coarsely pulverized, and finely pulverized using a fine pulverizer using a jet stream. Further, the finely pulverized product obtained was subjected to strict classification of ultrafine powder and coarse powder at the same time with a multi-division classifier (Elbow Jet classifier manufactured by Nittetsu Mining Co., Ltd.) utilizing the Coanda effect to give a weight average particle size of 8. 5 μm black fine powder (negatively chargeable black toner) was obtained. The acid value of the obtained black fine powder is 35 mgK
It was OH / g.

100 parts of the obtained black toner and a hydrophobic titanium oxide fine powder (average particle size 25n
m) 0.8 part was mixed with a Henschel mixer to prepare a black toner to which hydrophobic titanium oxide was externally added.

Next, a black toner was mixed with a carrier in which ferrite particles having an average particle diameter of 65 μm were coated with a silicone resin to prepare a two-component type developer. The mixing ratio is carrier 95
5 parts of black toner was used for each part.

This two-component developer was introduced into a commercially available color electrophotographic copying machine CLC-500 (manufactured by Canon Inc.) and a copying test was conducted.

When copying was performed in an environment of normal temperature and normal humidity, a good image having a density of 1.67 was obtained from the initial stage. The transfer efficiency of the toner from the photoconductor to the transfer paper was as good as 93%. Further, since the scattering of toner in the transfer process is remarkably improved, a very smooth halftone image and a sharp image can be obtained. Also, 20,
After copying 000 sheets, a good image having a density of 1.68 was obtained. No deterioration in image quality was observed with the increase in the number of copies. The transfer efficiency was 94%, which was not a tendency to decrease.

Even under environmental conditions of low temperature and low humidity, a good image with a density of 1.65 was obtained from the initial stage. After copying 20,000 sheets, the phenomenon of reduction in image density was not observed. In addition, the deterioration of the image quality such as the smoothness of the halftone image and the sharpness of the image with the increase in the number of copies was not observed.

Next, a similar copying test was carried out under high temperature and high humidity environmental conditions, and a good image having a density of 1.70 was obtained from the initial stage. After copying 20,000 sheets, the phenomenon of reduction in image density was not observed. In addition, the deterioration of the image quality such as the smoothness of the halftone image and the sharpness of the image with the increase in the number of copies was not observed.

Comparative Example 3 A toner was produced in the same manner as in Example 8 except that the urea compound (2) was replaced with the urea compound of Comparative Example 1.

A copy test was conducted in the same manner as in Example 8.

When copying was performed in an environment of normal temperature and normal humidity, a good image with a density of 1.73 was obtained in the initial stage, but after that, toner scattering suddenly occurred and the copying test was stopped after 1,000 sheets. .

When the surfaces of the toner particles were observed with an electron microscope, filamentous substances were found.

Example 9 Styrene-butylmethacrylate-monobutylmalate copolymer 100 parts Magnetic material (average particle size: 0.2 μm) 90 parts Low molecular weight polypropylene 4 parts Urea derivative polymer (1) (n = 3) ~ 50) 2nd

After thoroughly mixing the above materials with a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 130 ° C. The obtained kneaded product was cooled, coarsely pulverized, and finely pulverized using a fine pulverizer using a jet stream. Furthermore, the finely pulverized product thus obtained was subjected to strict classification of ultrafine powder and coarse powder at the same time using a multi-division classifier utilizing the Coanda effect (Elbow Jet classifier manufactured by Nittetsu Mining Co., Ltd.) to obtain a weight average particle size of 7. 5 μm black fine powder (negatively chargeable magnetic toner) was obtained.

The saturation magnetization of this magnetic toner is 38 Am ² /
kg, acid value was 10 mgKOH / g.

100 parts of the obtained black magnetic toner was subjected to a hydrophobic treatment with a fine hydrophobic silica powder (average particle size: 15 μm).
m) 0.6 part and strontium titanate (average particle size 1μ
m) 2 parts were mixed with a Henschel mixer to prepare a one-component magnetic toner.

The obtained one-component magnetic toner was introduced into a commercially available electrophotographic copying machine NP-6060 (manufactured by Canon Inc.) to obtain a temperature of 23 ° C. and a relative humidity of 60% in an environment of 20,0.
A 00 copy test was conducted.

As a result, a clear image having an image density of 1.41 was obtained from the initial stage. The image after copying 20,000 sheets was also clear with a density of 1.40.

The transfer efficiency of the toner from the photoconductor onto the transfer paper was good at 93%.

When a similar copying test was conducted under the environment of low temperature and low humidity and high temperature and high humidity, the same good result as the result under the environment of normal temperature and normal humidity was obtained.

Example 10 In the same manner as in Example 1 except that 4 parts of the urea derivative polymer (10) was used instead of 2 parts of the urea derivative polymer (1), a weight average particle diameter of 8.5 μm was obtained. A magnetic toner was obtained.

A copy test was conducted on the obtained magnetic toner in the same manner as in Example 1.

As a result, a clear image having an image density of 1.34 was obtained from the beginning. The image after copying 20,000 sheets was also clear with a density of 1.37.

The transfer efficiency of the toner from the photoconductor onto the transfer paper was as good as 87%.

When a similar copying test was conducted under the environment of low temperature and low humidity and high temperature and high humidity, the same good result as the result under the environment of normal temperature and normal humidity was obtained.

[0160]

The toner of the present invention contains a polymer having a urea derivative as a partial structural unit, so that the transfer efficiency is good and the environmental stability is excellent.

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Claims (4)

[Claims] 1. A toner for developing an electrostatic charge image, comprising a binder resin and a polymer having a urea derivative as a partial structural unit. 2. The toner for developing an electrostatic charge image according to claim 1, wherein the urea derivative is an arylurea derivative. 3. The acid value of the toner is 5 to 40.
The toner for developing an electrostatic image as described in 1. 4. The toner for developing an electrostatic charge image according to claim 1, which contains an inorganic oxide having a metal ion electronegativity of 10 to 15.