JPS61217057A - Electrostatic charge image developing toner - Google Patents

Abstract

PURPOSE:To stabilize triboelectrification amt., to render its distribution sharp and uniform, to optimize a development system, and to obtain a sharp image without being affected by temp. and humidity by incorporating a specified org. tin compd. as an electrostatic charge controller. CONSTITUTION:A toner contains the org. tin compd. stable against heat and time lapse, small in hygroscopicity and superior in charge control performance represented by the formula shown on the right in which R is 1-24C alkyl, aryl, or aralkyl, and R' is 1-12C alkylene. The use of such a charge controller permits triboelectrification amt. between toner particles themselves, between toner particles and carrier particle, and between those and a toner carrying body to be stabilized, its distribution to be made sharp and uniform, and this amt. to be adapted to a development system, accordingly, development and transfer to be enhanced in fidelity to a latent image, fixability to be improved, and trouble in a cleaning step, such as the stain and the damage of the latent image, to be prevented, the agglomeration of the toner to be prevented, and a sharp chromatic color image to be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a new toner for developing electrostatic images in electrophotography, electrostatic recording, electrostatic printing, and the like.

[Conventional technology]

Conventionally, as an electrophotographic method, U.S. Patent No. 2,297°89
1, Special Publication No. 42-23910, and Special Publication No. 43
Various methods are described in Japanese Patent No. 24748, etc., but in short, these methods apply a uniform electrostatic charge on a photoconductive insulating layer and irradiate the insulating layer with a light image to generate static electricity. An electrostatic latent image is formed, and then this latent image is developed and visualized using a fine powder called toner using the relevant technology. After transferring the powder image to paper or the like as necessary, it is fixed by heating, pressure, or solvent vapor. This is what we do.

The developing methods applied to these electrophotographic methods include:
Broadly speaking, there are dry development methods and wet development methods. The former method is further divided into a method using a two-component developer and a method using a -component developer.

Two-component developing methods include a magnetic brush method using an iron powder carrier, a cascade method using a bead carrier, a fur brush method using fur, etc., depending on the type of carrier for conveying the toner.

In addition, those belonging to the -component type development method include a powder cloud method in which toner particles are sprayed, and a contact development method (contact development, or (also referred to as toner development), jumping development method in which toner particles are not brought into direct contact with the electrostatic latent image surface, but are charged and flown toward the latent image surface by the electric field of the electrostatic latent image; and magnetic conductive method. There is the MagneDry method, which develops by bringing a toner into contact with the electrostatic latent image surface.

Conventionally, toners used in these development methods are fine powders in which dyes and pigments are dispersed in natural or synthetic resins. Finely pulverized particles of about 1 to 30 liters are used as toner. As the magnetic toner, one containing magnetic particles such as magnetite is used. In the case of a system using a so-called two-component developer, the toner is usually mixed with carrier particles such as glass beads and iron powder. Further, the toner is made to have a positive or negative charge depending on the polarity of the electrostatic latent image to be developed.

In order to make the toner hold an electric charge, it is also possible to use the triboelectricity of the resin that is a component of the toner, but since the toner's chargeability is small with this method, the image obtained by development is prone to fogging and is unclear. Become something. Therefore, in order to impart desired triboelectrification properties to toners, dyes and pigments that impart electrostatic properties, as well as charge control agents, are added.

Charge control agents known in the art today include the following:

(1) The following substances are used to control the toner to be positively charged.

dicrosine, azine dyes containing an alkyl group having 2 to 1B carbon atoms (Japanese Patent Publication No. 1827/1983), basic dyes (e.g. C,1,Ba5ic Yellow 2 (C,1
, 41000), CA, Bmsic Yellow
3, C,1,Ba5ic Red 1 (C,I.

45180), C,1,Ba5ic Red 9 (C
, 1,42500), C,I.

Ba5ic Violet 1 (C, 1, 42535
), C,1,Ba5icViolet 3 (C,
1,42555), C,1,Ba5ic Viol
etlo(C,1,45170),C,1,Ba5ic
Violet 14 (C,I.

42510), C, 1, Ba5ic Blue l
(C01,42025), C,I.

Ba5ic alum 3 (C, 1,5100
5), C,1,Ba5ic Blue5 (C,1
, 42140), C, 1, Ba5ic Blue
7 (C, I.

42595), C, 1, Ba5ic Blue 9
(C-1, 52015), C,I.

Ba5ic Blue 24 (ill:, 1.
52030), C, 1, Ba5ic Blue25
CC, 1, 52025), C, 1, Ba5ic B
lue 2G (C, I.

44045), C, l Ba5ic Green
1 (C, 1, 42040), G, 1. Ba
5ic Green 4 (C, 1,42000),
), lake pigments of these basic dyes (lakeing agents include phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.) , C,1,5olvent Black 3
(C.

1, 28150), Hansa Yellow G (C, 1, 11
880), C.

1, Mordant Black 11.
C, 1, Pigmsnt Black 1° Gilt night, asphalt, etc.

Quaternary ammonium salts, such as benzylmethyl-hexadecyl ammonium chloride, decyl-trimethylammonium chloride, organotin compounds such as dibutyltin oxide, metal salts of higher fatty acids, inorganic fine powders such as glass, mica, and zinc oxide, EDTA, Polyamine resins such as metal complexes of acetylacetone, vinyl polymers containing amino groups, and condensation polymers containing amino groups.

(2) The following substances can be used to control the negative chargeability of toner.

Metal complex salts of heptanoazo dyes described in Japanese Patent Publications No. 41-20153, No. 43-27598, No. 44-83i117, No. 45-28478, etc.

Dyes and pigments such as nitrofumic acid and its salts or C,1,14845 described in JP-A-50-133338, JP-B No. 55-42752, JP-B-Sho 5B-415
No. 08, Special Publication No. 59-7384, Special Publication No. 59-738
Metal complexes such as Go, Cr, and Fs of salicylic acid, naphthoic acid, and dicarboxylic acids described in No. 5, sulfonated copper phthalocyanine pigments, nitro groups, styrene oligomers with halogens introduced, chlorinated paraffins,
Melamine resin etc.

Many of these charge control agents are derived from dyes and pigments.
Generally, they have a complex structure, and many of them have strong coloring properties.

Recently, there are some newly proposed products that are different from these, but none have superior overall performance to dyes and pigments, and examples of dyes and pigments still being used are still unsatisfactory. Most of them are.

These are usually added to thermoplastic resins, thermally melted and dispersed, and then finely pulverized and adjusted to a suitable particle size as necessary before use.

However, these dyes used as charge control agents have complex structures, inconsistent properties, and poor stability, and are susceptible to decomposition during thermal kneading, mechanical impact, friction, changes in temperature and humidity conditions, etc. Otherwise, it is likely to change in quality and cause a phenomenon in which charge controllability is deteriorated.

Therefore, if a toner containing these dyes as a charge control agent is used in a copying machine to develop it, the charge control agent may decompose or change in quality as the number of copies increases, which may cause the toner to deteriorate during durability. .

Furthermore, since it is extremely difficult to uniformly disperse these charge control agents in thermoplastic resins, they have the fatal drawback of causing a difference in the amount of frictional charge between toner particles obtained by pulverization. are doing. For this reason, various methods have been used to achieve more uniform dispersion6.For example, basic nigrosine dyes have been treated with higher fatty acids to form salts in order to improve their compatibility with thermoplastic resins. However, unreacted fatty acids or salt dispersion products are often
It is exposed on the toner surface and contaminates the carrier or toner support, causing a decrease in the fluidity of the toner, fog, and a decrease in image density. Alternatively, in order to improve the dispersion of these charge control agents into the resin, a method has also been adopted in which the charged M-divided powder and the resin powder are mechanically pulverized and mixed in advance, and then the mixture is hot-melted and kneaded. but,
The inherent poor dispersion cannot be avoided, and the current situation is that sufficient charge uniformity has not yet been obtained for practical use.

Further, most of the substances generally known as charge control agents have a dark color and cannot be incorporated into a bright chromatic developer.

In addition, many charge control agents are hydrophilic, and due to poor dispersion in these resins, dyes are exposed on the toner surface when crushed after melt mixing, and under high humidity conditions, these charge control agents It has the disadvantage that it is difficult to obtain high-quality images because it is tree-like.

In this way, when conventional charge control agents are used in toner,
Between toner particles, between toner and carrier, between toner and sleeve, and between toner and carrier,
This causes variations in the amount of charge generated on the surface of toner particles, which tends to cause problems such as development fog, toner scattering, and carrier contamination, and these problems become noticeable when copying is repeated many times. The result is practically unsuitable for copying machines.

Furthermore, under high humidity conditions, the transfer efficiency of toner images decreases significantly, making many toner images unusable.Even at room temperature, when the toner is stored for a long time, the charge used Due to the instability of the control agent, it often undergoes deterioration and becomes unusable due to poor charging properties.

Furthermore, when conventional charge control agents are used in toner, long-term use may cause the charge control agents to adhere to the surface of the photoreceptor or promote toner adhesion, adversely affecting latent image formation (
There are many things that have a negative effect on the cleaning process of multi-function devices, such as the filming phenomenon), those that cause scratches on the surface of the photoreceptor or cleaning members such as cleaning blades, and those that accelerate wear of these members.

Furthermore, when conventional charge control agents are used in toner, there are many that have a large effect on the thermal melting properties of the toner and reduce fixing performance.In particular, they deteriorate offset resistance at high temperatures, and when heated on a heat roll of 51F. Increases the ability of the transfer material to cling to the roller.

There are some things that reduce the durability life of the roller.

As described above, conventional charge control agents have many drawbacks.
There is a strong demand in the technical field to improve these.
Although many improved techniques have been proposed so far, the reality is that no one has yet been found that is comprehensively satisfactory for practical use.

[Problem that the invention seeks to solve]

An object of the present invention is to provide a new technique for toner charge control that overcomes these drawbacks.

The object of the present invention is to stabilize the amount of triboelectric charge between toner particles, between toner and carrier, or between toner and a toner carrier such as a sleeve in the case of -component development, and to have a sharp triboelectricity distribution. The purpose of the present invention is to provide a developer which is uniform and whose charge amount can be controlled to suit the developing system used.

Still another object is to develop a developer that is faithful to the latent image and to perform the transfer, that is, without toner adhesion in the background area during development, without fogging or toner scattering around the edges of the latent image. High image density can be obtained,
To provide a developer with good halftone reproducibility.

Still another object is to provide a developer that maintains its initial characteristics even when the developer is used continuously over a long period of time, and that causes no toner aggregation or change in charging characteristics.

Zara's other purpose is to develop a developer that reproduces stable images that are not affected by changes in temperature and humidity, especially a developer that has high transfer efficiency and does not cause splatters or transfer omissions during transfer at high or low humidity. It is provided by.

Another objective is to provide a bright chromatic developer.

Still another object is to provide a developer with excellent storage stability that maintains its initial characteristics even during long-term storage.

Still another object is to provide a developer that does not stain, abrade, or scratch the electrostatic latent image surface and is easy to clean.

Still another object is to provide a developer that has good fixing properties and is free from problems such as special instantaneous high temperature offset.

[Means for solving problems]

The present invention relates to an electrophotographic toner for developing electrostatic images, which is characterized by containing an organic compound represented by the general formula (1).

(In the formula, R is a C8-C12 alkyl group, cyclic alkyl group, aryl group, aralkyl group, R' is a C8-C12
The present inventors found that the above compound CI) is thermally and temporally stable, has low hygroscopicity, and when contained in a developer, provides a developer with excellent electrophotographic properties. The present invention was achieved by discovering that it is a high quality charge control agent.

In general formula [1], the substituent R is a methyl group,
01 to C24 alkyl groups that may be branched such as ethyl group, propyl group, butyl group, hexal group, dodecyl group, hexadecyl group, octadecyl group, eicosyl group;
Cyclic alkyl groups such as cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclooctyl group; 7-aryl groups such as phenyl group, tolyl group, butylphenyl group, butoxyphenyl group, chlorphenyl group; benzyl group, phenethyl group, methylbenzyl group Typical substituents include aralkyl groups such as R', and methyl, ethylene, propylene, and butylene groups.

These compounds are synthesized by known methods.

That is, the corresponding disubstituted tin sulfoxide is dispersed using benzene, toluene, or xylene as a solvent, and the corresponding 1,000-ol is applied thereto. The reaction in which a tin alkylthio compound is synthesized by the dehydration reaction of thiol and tin sulfoxide is carried out by boiling the dispersion solution and removing the water produced as an azeotrope during the reaction.

Typical specific examples of the organic tin compound represented by the general formula [1] include the following.

[Compound example] Generally, the above compounds have an average particle size of 10 to 0.10 l.

In particular, it is preferable to use the particle size in the range of 5 to 0.1 μl for toner adjustment.

Methods for incorporating the above compound into the developer include a method of adding it inside the developer and a method of adding it externally. When internally added, the amount of these compounds used is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner manufacturing method, including the dispersion method, and is uniquely limited. However, it is preferably 0.1 to 20 parts by weight (more preferably 0.1 to 20 parts by weight) per 100 parts by weight of the binder resin.
(5 to IO parts by weight).

In addition, when externally added, 0.0 parts by weight per 100 parts by weight of resin.
1 to 10 parts by weight is preferred.

Furthermore, conventionally known charge control agents can be used in combination with the charge control agent of the present invention.

Colorants used in the present invention include carbon black, lamp black, iron black, ultramarine blue, nigrosine dye, aniline blue, phthalocyanine blue, phthalocyanine green, Hansa Yellow G, rhodamine 8G lake, calco oil blue, chrome yellow, and quinacridone. Any conventionally known dyes and pigments such as , benzidine yellow, rose bengal, triallylmethane dyes, monoazo dyes, disazo dyes and pigments can be used alone or in combination.

The binder resin used in the present invention includes polystyrene,
Monopolymers of styrene and its substituted products such as polyp-chlorostyrene and polyvinyltoluene; styrene-p-chlorostyrene copolymers, styrene-propylene copolymers,
Styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer Coalescence, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-methyl chloromethacrylate copolymer, styrene-acrylonitrile copolymer, styrene- Vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene- Styrenic copolymers such as maleic acid copolymers and styrene-maleic ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, polyurethane, polyamide, epoxy resins , polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc., singly or in combination. It can be used as

In particular, as binder resins suitable for pressure fixing, the following can be used alone or in combination.

Polyolefin (low molecular weight polyethylene, low molecular weight polypropylene, polyethylene oxide, polytetrafluoroethylene, etc.), epoxy resin, polyester resin, styrene-butadiene copolymer (monomer ratio 5-30:95-70)
, olefin copolymers (ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, ethylene-
methacrylic ugly copolymer, ethylene-methacrylic acid ester copolymer, ethylene-vinyl chloride copolymer, ethylene-vinyl acetate copolymer, ionomer resin), polyvinylpyrrolidone, methyl vinyl ether-maleic anhydride copolymer, maleic acid Modified phenolic resin, phenol-modified terpene resin.

Further, when the toner of the present invention is used as a two-component developer, it is used in combination with a carrier powder.

All known carriers can be used in the present invention, such as magnetic powders such as iron powder, ferrite powder, and nickel powder, glass beads, etc., and carriers whose surfaces have been treated with resin, etc. Things can be given.

Furthermore, the toner of the present invention can contain a magnetic material and be used as a magnetic toner. The magnetic materials contained in the magnetic toner of the present invention include iron oxides such as magnetite, hematite, and ferrite, iron, cobalt, and nickel. metals such as aluminum, cobalt, copper,
Examples include alloys with metals such as lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, and vanadium, and mixtures thereof.

These ferromagnetic materials preferably have an average particle size of about 0.1 to 2 tons, and are contained in the toner in an amount of about 20 to 2 QQ parts by weight per 100 parts by weight of the resin component, particularly preferably about 100 parts by weight of the resin component. It is about 40 to 150 parts by weight.

The toner of the present invention may also contain additives as required. Examples of additives include lubricants such as Teflon and zinc stearate, abrasives such as cerium oxide and silicon carbide, and colloidal additives. Fluidity imparting agents such as silica and aluminum oxide, anti-caking agents,
Alternatively, conductivity imparting agents such as carbon black and tin oxide, fixing aids such as low molecular weight polyethylene, etc. may also be used.

To prepare the toner for developing an electrostatic image according to the present invention, the charge control agent according to the present invention is mixed with a vinyl or non-vinyl thermoplastic resin, a pigment or dye as a coloring agent, a magnetic material as necessary, Additives, etc. are thoroughly mixed using a ball mill or other mixer, and then melted, kneaded, and kneaded using a heat kneader such as a heated roll, niegu, or extorter to make the resins mutually dissolve. A toner having an average particle size of 5 to 201 L can be obtained by dispersing or dissolving a pigment or dye in the toner, cooling and solidifying it, and then crushing and classifying it.

Alternatively, the material can be obtained by dispersing the material in a binder resin solution and then spray-drying it, or by mixing the specified material with the monomers that should constitute the binder resin to form an emulsified suspension and then polymerizing it. Methods such as a polymerization method for producing toner to obtain a toner can be applied.

Toners produced by these methods can be used for developing to visualize electrostatic images in electrophotography, electrostatic recording, electrostatic printing, etc. by any conventionally known means, and can be used as follows: It has excellent effects.

In other words, the amount of frictional charge between toner particles is uniform, and (the amount of load can be easily controlled).Also, the toner is extremely stable as the amount of frictional charge does not vary or decrease due to deterioration during use. Therefore, the above-mentioned problems such as development fog, toner scattering, and contamination of electrophotographic photosensitive materials and copying machines are eliminated, and phenomena such as toner aggregation, clumping, and low-temperature flow during storage, which were major drawbacks in the past, are eliminated. It is a toner that can withstand long-term storage, and also has excellent abrasion resistance, fixing properties, and adhesive properties of toner images.

These excellent effects of the toner are further magnified when used in a repetitive transfer copying system in which the operations of charging, exposure, development, and transfer are successively repeated. Furthermore, since there is little color disturbance caused by the charge control agent, it is possible to form color images with excellent colors when used as a color electrophotographic toner.

〔Example〕

The present invention will be specifically explained below with reference to Examples, but this is not intended to limit the present invention in any way. All parts in the following formulations are by weight.

Example 1 Styrene/butyl acrylate (80/20) copolymer 100 parts (weight average molecular weight M%I: approximately 300,000) Carbon black (Mitsubishi #44) 10 parts Individual molecular weight polyethylene wax 2 parts Compound (1)
Two parts of the above materials were thoroughly mixed in a blender and then kneaded with two rolls heated to 150°C. After the kneaded material is left to cool naturally, it is roughly pulverized using a cutter mill, then pulverized using a pulverizer using a jet stream, and further classified using an air classifier to obtain a fine powder with a particle size of 5 to 20 l. Obtained.

A developer was prepared by mixing 5 parts of the fine powder with 100 parts of iron powder carrier having an average particle size of 50 to 80 IL.

Next, by a conventionally known electrophotographic method,
A negative electrostatic image was formed, and this was powder-developed using the above-mentioned developer using a magnetic brush method to create a toner image, which was transferred to plain paper and heat-fixed. The resulting transferred image had a sufficiently high density, no fogging, and no toner scattering around the image, resulting in a good image with high resolution. Transfer images were created continuously using the above developer to examine durability.
The transferred image after 30,000 sheets is also compared with the initial image,
It was a completely unremarkable image.

Further, during durability, the above-mentioned filming phenomenon related to toner on the photoreceptor was not observed at all, and no problems were found in the cleaning process. Also, there were no troubles in the fixing process at this time (at the end of the 30,000-sheet durability test, the fuser was disassembled and observed, but there were no scratches or damage to the rollers, and there was almost no dirt from offset toner, making it practical.) There were no problems at all.

In addition, when the environmental conditions were set to 35°C and 85%, the image density was almost the same as at room temperature and humidity, clear images with no fogging or scattering were obtained, and the durability remained unchanged up to 30,000 sheets. When a transferred and fixed image was obtained at a low temperature and low humidity of 0.15" and 0.10%, the image density was sufficiently high, solid black was developed and transferred extremely smoothly, and the image was excellent with no scattering or hollow spots. Durability was carried out under these environmental conditions, and although copies were made continuously and intermittently,
Again, the density fluctuation was ±0.2 up to 30,000 sheets, which was sufficient for practical use.

Comparative Example 1 A developer was obtained in the same manner as in Example 1, except that 2 parts of nigrosine dye (Nigrosine Base EX manufactured by Orient Chemical Industry Co., Ltd.) was used instead of 2 parts of compound (1), and development, transfer, and fixing were carried out in the same manner. I got the image.

At room temperature, there was little fog, but the image density was low at 1.06, line drawings were scattered, and solid black was noticeably rough. Durability was examined and the density decreased to 0.83 after 30,000 sheets.

Further, during durability, after about 10,000 copies, the toner material formed a film in the form of thin stripes on the surface of the photoreceptor and began to appear as lines on the image. This is so-called filming, and is thought to be due to the charge control agent changing the lubricity of the toner powder.

Furthermore, during durability, the fixed image tended to get caught up in the fixing roller during the fixing process, and there was difficulty in peeling it off from the roller.

When an image was obtained under conditions of 35° C. and 185%, the image density was as low as 0.88, and fogging, scattering, and roughness increased. Transfer efficiency was also low.

When an image was obtained under conditions of 15° C. and 110%, the image density was as low as 0.91, and there were severe scattering, fogging, and roughness, and four transfer defects were noticeable. I tried to take continuous images, but
After about 30,000 sheets, the density became 0.53, making it impractical.

Example 2 A developer was obtained in the same manner as in Example 1 except that 3 parts of compound (2) was used instead of 2 parts of compound (1), and an image was obtained in the same manner by performing development, transfer, and fixing.

The detailed results are shown in Tables 1 and 2, and satisfactory results almost the same as in Example 1 were obtained.

Example 3 A developer was obtained in the same manner as in Example 1 except that 2 parts of compound (3) was used instead of 2 parts of compound (1), and development, transfer, and
Fixation was performed and an image was obtained in the same manner.

The detailed results are shown in Tables 1 and 2, and almost the same satisfactory results as in Example 1 were obtained.

Example 4 A developer was obtained in the same manner as in Example 1 except that 2 parts of Compound (0) was used instead of 2 parts of Compound (1), and an image was obtained in the same manner by performing development, transfer, and fixing.

The detailed results are shown in Tables 1 and 2, and almost the same satisfactory results as in Example 1 were obtained.

Example 5 Styrene/butyl acrylate (so/20) copolymer 100 parts (weight average molecular weight Mw: approximately 300,000) Triiron tetroxide EPT-500 (manufactured by Toda Kogyo) SO part partial molecular weight polypropylene wax 2 parts Compound (
1) 2 parts The above materials were thoroughly mixed in a blender and then kneaded with two rolls heated to 150°C. After the kneaded material was left to cool naturally, it was roughly pulverized using a cutter mill, then pulverized using a pulverizer using a jet stream, and further classified using an air classifier to obtain a fine powder with a particle size of 5 to 20 IJ. Obtained.

Next, hydrophobic colloidal silica R was added to 100 parts of the fine powder.
0.4 part of -972 (manufactured by Nippon Aerosil Co., Ltd.) was mixed in a sample mill to prepare a -component magnetic toner.

When this toner was applied to a reprint copying machine (trade name NP-1502, manufactured by Canon Building Co., Ltd.) to produce an image, good results almost the same as in Example 1 were obtained.

Example 6 A developer was obtained in the same manner as in Example 5, except that 3 parts of compound (2) was used instead of 2 parts of compound (1), and development, transfer, and fixing were carried out in the same manner. I got it.

Detailed results are shown in Tables 1 and 2, and almost the same satisfactory results as in Example 5 were obtained.

Example 7 A developer was obtained in the same manner as in Example 5, except that 2 parts of compound (3) was used instead of 2 parts of compound (1), and development, transfer, and fixing were carried out in the same manner as in Example 5. I got it.

The detailed results are shown in Tables 1 and 2, and almost the same satisfactory results as in Example 5 were obtained.

Comparative Example 2 A developer was obtained in the same manner as in Example 5, except that 2 parts of benzylmethyl-hexadecyl ammonium chloride was used instead of 2 parts of Compound (1) in Example 5, and an image was obtained in the same manner. At room temperature and humidity, there is little fog, but the image density is 0.8
1 and the line drawings were scattered, and the solid black was noticeably rough. I checked the durability, and the density was 0.4 after 30,000 sheets.
It dropped to 8.

In addition, the above-mentioned filming phenomenon during durability and problems in the fixing process were almost the same as those in Comparative Example 1, and were undesirable. When an image was obtained under the condition of φ 35°C and 185%, the image density was as low as 0°72. Fog, splatter, and roughness increased, making it unusable. Transfer efficiency was also low. When an image was obtained under the conditions of 15° C. and 10%, the image density was as low as 0.73, and there was severe scattering, fogging, roughness, and transfer omissions were noticeable. Continuous image formation was performed, but the density became 0.58 after 30,000 sheets, making it impractical.

Example 8 Styrene/butyl acrylate (80/20) copolymer 100 parts (weight average molecular weight Mw: approximately 300,000) Copper phthalocyanine blue pigment 5 parts Low molecular weight polypropylene wax 2 parts Compound (1) 2 parts The above materials were mixed with Brengu. After thorough mixing, the mixture was kneaded using two rolls heated to 150°C. After the kneaded material is left to cool naturally, it is roughly pulverized using a cutter mill, then pulverized using a pulverizer using a jet stream, and further classified using an air classifier to obtain a fine powder with a particle size of 5 to 20 l. Obtained.

Next, 50 g of magnetic particles having a particle size of 50 to 5 oIL were mixed with 100 parts of the fine powder to prepare a developer.

When one image was produced using this developer using the development method described below, a good image with a bright blue color was obtained, and after producing 1,500 images, the toner/carrier was 10
Even when the weight was 150 g, there was almost no change in image density, and after that, images were printed on up to 30,000 sheets while replenishing toner, and good images were obtained.

This developing method will be explained using FIG. 1.

The carrier-toner mixture formed on the toner carrier 2 is circulated by the magnetic brush 52 by rotating the toner carrier 2, and the toner in the hopper 3 is taken in and coated in a uniform thin layer on the carrier 2. Then, the toner carrier 2 and the electrostatic image carrier 1 are opposed to each other with a gap larger than the thickness of the toner layer, and the toner 5 on the carrier 2 is developed by flying onto the electrostatic charge image on the electrostatic image carrier l. let

The thickness of one layer of toner is controlled by the size of the magnetic brush 52, the amount of magnetic particles, and the regulating blade 5B. The gap between the electrostatic image carrier 1 and the toner carrier 2 may be made larger than the thickness of the toner, and the developing bias 6 may be applied.

The evaluation results of each example and comparative example are shown in Tables 1 and 2. In Table 1, 0 represents good, 0Δ represents slightly good, Δ represents slightly poor, and × represents poor.

〔Effect of the invention〕

The effects obtained by the present invention are as follows.

By using the toner for developing electrostatic images of the present invention, (1) the amount of triboelectric charge between toner particles, between toner and carrier, between toner and toner carrier such as a sleeve in the case of -component development is stabilized; .

In addition, the triboelectric charge distribution becomes sharp and uniform, and the charge amount can be controlled to suit the developing system used.

(2) It is possible to develop and transfer a latent image faithfully, and even when used continuously for a long period of time, it maintains its initial characteristics and does not cause toner aggregation or change in charging characteristics.

(3) Stable images that are unaffected by changes in temperature and humidity can be reproduced, and images in vivid chromatic colors can be obtained.

(4) The cleaning process is facilitated without staining, abrading, or scratching the electrostatic latent image surface, and the fixing properties are excellent, and there are no problems even with high-temperature offset, which is particularly likely to cause trouble.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an example of a developing device to which the positively chargeable toner according to the present invention can be applied. l... Electrostatic image holder, 2... Toner carrier, 3...
...Hopper 5...Toner. 6...Bias, 50...Magnet, 52...
Magnetic brush, 58...Regulation blade. Figure 1

Claims (1)

[Scope of Claims] An electrophotographic toner for developing an electrostatic image, which is characterized by containing an organic compound represented by the general formula [1]. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [1] (In the formula, R is an alkyl group of C_1 to C_2_4, a cyclic alkyl group, an aryl group, an aralkyl group, and R' is an alkyl group of C_1 to C_2_4.
Indicates the alkylene group of C_1_2. )