JPH0656508B2 - Positive friction charging toner for electrostatic image development - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a novel positive triboelectric charging toner for developing an electrostatic charge image in electrophotography, electrostatic recording, electrostatic printing and the like.

BACKGROUND ART Conventionally, US Pat. No. 2,297,69 has been used as an electrophotographic method.
No. 1, JP-B-42-23910, and JP-B-43.
No. 24748, etc., various methods are described. In short, they apply a uniform electrostatic charge on a photoconductive insulating layer and irradiate the insulating layer with a light image to obtain a static image. An electrostatic latent image is formed, then the latent image is developed and visualized by fine powder called toner in the art, and if necessary, the powder image is transferred to paper or the like, and then heated, pressurized, or by solvent vapor. It is to fix.

As a developing method applied to these electrophotographic methods,
It is roughly classified into a dry development method and a wet development method. The former is further divided into a method using a two-component developer and a method using a one-component developer. Among the two-component developing methods, there are a magnet brush method using an iron powder carrier, a cascade method using a bead carrier, a fur brush method using a fur, etc., depending on the type of carrier that carries the toner.

The one-component developing method includes a powder cloud method in which toner particles are sprayed, a contact developing method in which toner particles are directly brought into contact with an electrostatic latent image surface for development (contact development, or toner development). (Also referred to as development), a jumping development method in which toner particles are not directly contacted with the electrostatic latent image surface, but the toner particles are charged and fly toward the latent image surface by the electric field of the electrostatic latent image, magnetic conductivity. There is a magnetic dry method in which toner is brought into contact with the electrostatic latent image surface to develop the toner.

As a toner applied to these developing methods, conventionally, one obtained by dispersing a dye or pigment in a natural or synthetic resin is used.
Particles finely pulverized to about 30 μm are used as a toner. As the magnetic toner, one containing magnetic particles such as magnetite instead of or in addition to the above-mentioned dye or pigment is used. In the case of a system using a so-called two-component developer, the toner as described above is usually used by being mixed with carrier particles such as glass beads and iron powder.

Further, the toner is given a positive or negative charge in advance according to the polarity of the electrostatic latent image to be developed.

To impart an electric charge to the toner, it is possible to use only the triboelectric chargeability of the resin, which is a component of the toner, but in this method the toner chargeability is small, so the image obtained by development is easily fogged and is not clear. It will be Therefore, in order to impart a desired triboelectric charging property to the toner, a charge control agent such as a dye or a pigment which enhances the charging property is added.

Examples of charge control agents known in the field of electrophotography today include the following.

(1) Controlling the toner to be positively charged Nigrosine, an azine dye containing an alkyl group having 2 to 16 carbon atoms (Japanese Patent Publication No. 42-1627), a basic dye (for example, CIBasic Yellow 2 (CI41000), CIBasic) Yellow
3, CIBasic Red 1 (CI45160), CIBasic Red 9 (CI
42500), CIBasic Violet 1 (CI42535), CIBasic Vio
let 3 (CI42555), CIBasic Violet 10 (CI45170), C.
I.Basic Violet 14 (CI42510), CIBasic Blue 1 (CI
42025), CIBasic Blue 3 (CI51005), CIBasic Blue
5 (CI42140), CIBasic Blue 7 (CI42595), CIBasic
Blue 9 (CI52015), CIBasic Blue 24 (CI52030), C.
I.Basic Blue25 (CI52025), CIBasic Blue 26 (CI44
045), CIBasic Green 1 (CI42040), CIBasic Green
4 (CI42000), CI45170, etc.). Lake pigments of these basic dyes (as a laker, phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.), CISolvent Black
3 (CI26150), Hansa Yellow G (CI11680), CI Morda
nt Black 11, CI Pigment Black 1, Gilsonite, asphalt, etc.

Quaternary ammonium salts such as benzyldimethyl-hexadecyl ammonium chloride, decyl-trimethyl ammonium chloride, organotin compounds such as dibutyltin oxide, metal salts of higher fatty acids, glass, mica, inorganic fine powders such as zinc oxide, EDTA, Metal complexes of acetylacetone, etc.

Polyamine resins such as amino group-containing vinyl polymers and amino group-containing condensation polymers.

(2) Controlling the toner to be negatively charged A metal complex salt of a monoazo dye described in JP-B Nos. 41-20153, 43-27596, 44-6397 and 45-26478.

Metal complexes of salicylic acid, oxynaphthoic acid, dicarboxylic acids such as Co, Cr and Fe described in JP-B-55-42752, JP-B-58-41508, JP-A-59-7384 and JP-A-59-7385.

Sulfonated copper phthalocyanine pigment.

Styrene oligomer with nitro group and halogen introduced. Chlorinated paraffin, melamine resin, etc.

However, as described above, the use of conventional charge control agents still has many problems to be improved. Sit down,
Many of these charge control agents are derived from dyes and pigments, and generally have a complicated structure, inconsistent properties, poor stability, and strong coloring properties. Recently, some of the proposed ones are different in system from the ones mentioned above, but none of them are superior in overall performance to those of the dye / pigment system, and despite many disadvantages as described below,
In most cases, dye-pigment type charge control agents are used.

That is, these charge control agents are usually added to a thermoplastic resin which is a binder resin of a toner and contained in a toner prepared through processes such as thermal melting dispersion, pulverization and classification. In the process, the dye / pigment type charge control agent described above often causes a problem. For example, as described above, these charge control agents are poor in stability as substances, and are easily decomposed or deteriorated by decomposition during thermal kneading, mechanical shock, friction, changes in temperature and humidity conditions, etc. The phenomenon that the property deteriorates is likely to occur. Further, when a toner containing these dyes and pigments as a charge control agent is developed in a copying machine, the charge control agent may be decomposed or deteriorated as the number of times of copying increases, causing deterioration of the toner during repeated copying operations. is there.

Further, since it is extremely difficult to uniformly disperse these charge control agents in the thermoplastic resin, there is a fatal problem that a difference in the triboelectric charge amount between the toner particles obtained by pulverization causes a difference. Have For this reason, various methods have been conventionally used for more uniform dispersion. For example, a basic nigrosine dye is used by forming a salt with a higher fatty acid in order to improve the compatibility with a thermoplastic resin, but unreacted fatty acid or a dispersion product of the salt is often formed on the toner surface. When it is exposed, it contaminates the carrier or the toner carrier, and causes a decrease in fluidity of toner, fog, and a decrease in image density. Alternatively,
In order to improve the dispersion of these charge control agents in the resin, a method of mechanically pulverizing and mixing the charge control agent powder and the resin powder in advance and then hot-melt kneading is used. However, the original poor dispersion cannot be avoided, and in the current situation, sufficient charge uniformity for practical use has not yet been obtained.

In addition, most of the substances generally known as charge control agents have a dark color, and thus there is a problem that they cannot be contained in a vivid chromatic color developer.

Further, many charge control agents are hydrophilic, and due to poor dispersion in these resins, the dye is exposed on the toner surface when pulverized after melt kneading. Therefore, when the toner is used under high humidity conditions, there is a problem that a high quality image cannot be obtained because the charge control agent is hydrophilic.

Thus, when the conventional charge control agent is used in the toner,
Between toner particles, between toner and carrier, between toner and toner carrier such as toner and sleeve,
The amount of electric charge generated on the surface of the toner particles varies, and problems such as development fog, toner scattering, and carrier contamination are likely to occur. Further, this obstacle appears as a remarkable phenomenon when the number of times of copying is increased, which is not suitable for a copying machine.

Further, under high humidity conditions, the transfer efficiency of toner images is significantly reduced, and many of them cannot be used. Even at room temperature and normal humidity, when the toner is stored for a long period of time, it deteriorates due to instability of the charge control agent used and often becomes unusable due to poor chargeability.

Furthermore, when a conventional charge control agent is used for a toner, the charge control agent itself adheres to the surface of the photoconductor due to long-term use, or the presence of the charge control agent promotes the adhesion of the toner (the occurrence of a filming phenomenon). In many cases, the cleaning process of the copying machine is inconvenient, such as adversely affecting the latent image formation, causing scratches on the surface of the photoconductor or a cleaning member such as a cleaning blade, or promoting wear of the member.

Furthermore, when a conventional charge control agent is used in a toner, it often causes a great influence on the heat melting property of the toner and deteriorates the fixing performance. In particular, there are inconveniences such as deterioration of high-temperature offset performance, increase of the sticking property of the transfer material to the roller at the time of heat roll fixing, and reduction of the durable life of the roller.

As described above, many problems are observed in the conventional charge control agents, and it is strongly requested in the technical field to solve these problems, and many improved techniques have been proposed so far. The reality is that we have not yet found anything practically satisfying.

OBJECT OF THE INVENTION It is a general object of the present invention to provide a new technique for controlling the positive triboelectric charge of a toner which overcomes these problems.

A more specific object of the present invention is to provide a stable positive triboelectric charge amount between toner particles, or between toner and carrier, between toner and a toner carrier such as a sleeve in the case of one-component development, and the triboelectric charge is stable. The quantity distribution is sharp and uniform,
It is to provide a toner capable of controlling the charge amount suitable for the developing system used.

Still another object is a developer that faithfully develops and transfers a latent image, that is, adhesion of toner in the background area at the time of development, that is, no fog or toner scattering around the edge of the latent image, The purpose of the present invention is to provide a positive triboelectrically chargeable toner that can obtain high image density and has good halftone reproducibility.

Still another object is to provide a positive triboelectric charging toner that maintains the initial properties even when continuously used for a long period of time, and does not cause aggregation or change in charging properties.

Still another object is a toner that reproduces a stable image that is not affected by changes in temperature and humidity, especially a positive friction charging property with high transfer efficiency that does not cause scattering or transfer omission during transfer at high humidity and low humidity. Toner is provided.

Still another object is to provide a bright chromatic color positive triboelectric charging toner.

Still another object is to provide a positive triboelectrically chargeable toner having excellent storage stability, which retains initial properties even after long-term storage.

Still another object is to provide a positive triboelectrification type toner which can be easily cleaned by a cleaning process that does not stain, wear or scratch the electrostatic latent image surface.

Still another object is to provide a toner having a good fixing property, particularly a positive triboelectric charging toner having no problem in high temperature offset and the like.

SUMMARY OF THE INVENTION Specifically, the present invention is characterized by containing a binder resin composed of a styrene-based copolymer, a colorant, and a chelate compound of salicylamine or alkylsalicylamine and iron, nickel or cobalt. The present invention relates to a positive triboelectric charging toner for developing an electrostatic image.

That is, the present inventors have found that the chelate compound of salicylamine or alkylsalicylamine (hereinafter, often referred to collectively as “(alkyl) salicylamine chelate”) has a charge control agent in the toner. In addition to exhibiting excellent charge controllability of positive triboelectric charge when included as, it is stable under heating and use over time, has low hygroscopicity, and is essentially colorless or pale color. The present invention has been completed by discovering that it has extremely effective characteristics for achieving the above object.

Hereinafter, the present invention will be described in more detail. In the following description, “part” and “%” representing the quantitative ratio are based on weight unless otherwise specified.

Detailed Description of the Invention In the present invention, it is used as a charge control agent (alkyl).
The salicylamine chelate includes, in addition to salicylamine, an alkylsalicylamine having 1 to 24 carbon atoms, particularly 1 to 3 alkyl groups having 1 to 16 carbon atoms, specifically 3
-Methyl salicylamine, 3-ethyl salicylamine,
3-isopropylsalicylamine, 3-n-butylsalicylamine, 3-stearylsalicylamine, 5-methylsalicylamine, 5-ethylsalicylamine, 5-n
-Propylsalicylamine, 5-t-butylsalicylamine, 5-laurylsalicylamine, 3,5-dimethylsalicylamine, 3,5-diethylsalicylamine,
3,5-di-n-propylsalicylamine, 3-methyl-5-ethylsalicylamine, 3-methyl-5-t-butylsalicylamine, 3-ethyl-5-t-butylsalicylamine, 3-methyl- 5-lauryl salicylamine, 3-ethyl-5-stearyl salicylamine, 3,
5-di-t-butyl salicylamine and the like,
Iron, nickel or cobalt can be mentioned as shown in Examples described later.

The above-mentioned (alkyl) salicylamine chelate can be synthesized by a known method. Generally, it is weakly alkaline in ammonia, and easily produced by adding an aqueous solution of (alkyl) salicylamine in ethanol to a metal aqueous solution and heating it. it can.

Generally, it is preferable that the (alkyl) salicylamine chelate has a mean particle size of 10 to 0.01 μm, and more preferably 2 to 0.1 μm for use in toner preparation.

The toner of the present invention can be obtained by blending the above-mentioned (alkyl) salicylamine chelate into a toner (fine colored powder) containing a binder resin and a colorant as essential components. As a form of compounding, either a so-called internal addition form in which the toner is uniformly or encapsulated in a toner or a so-called external addition form in which the toner is mixed and attached to the toner can be adopted.

When internally added, the amount of the (alkyl) salicylamine chelate used is determined according to the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method. However, it is preferably 0.1 to 100 parts by weight of the binder resin.
It is used in the range of 20 parts by weight (more preferably 0.5 to 10 parts by weight).

Further, when externally added, it is 0.
01 to 20 parts by weight is desirable.

If necessary, a conventionally known charge control agent can be used in combination with the charge control agent of the present invention.

As the binder resin of the toner, polystyrene, poly-p-
Monopolymers of styrene such as chlorostyrene and polyvinyltoluene, and their substitution products; styrene-p-chlorostyrene copolymers, styrene-propylene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene copolymers, Styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate Copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, Styrene-vinyl methyl ketone Styrene-based copolymers such as polymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer; poly Methyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester,
Polyurethane, polyamide, epoxy resin, 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. They can be used alone or in combination.

Further, as the binder resin suitable for giving a toner particularly 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: 95-7)
0), olefin copolymer (ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, ethylene-methacrylic acid copolymer, ethylene-methacrylic acid ester copolymer, ethylene-vinyl acetate copolymer, ionomer Resin), polyvinylpyrrolidone, methyl vinyl ether-maleic anhydride copolymer, maleic acid-modified phenol resin, phenol-modified terpene resin.

As the colorant, carbon black, lamp black,
Iron black, ultramarine, nigrosine dye, aniline blue, phthalocyanine blue, phthalocyanine green, Hansa yellow G, rhodamine 6G lake, chrome yellow, quinacridone, benzidine yellow, rose bengal, anthraquinone dye, triallylmethane dye, monoazo dye, disazo Conventionally known dyes and pigments such as dyes and pigments may be used alone or in combination.

Further, the toner of the present invention can be used as a magnetic toner by further containing a magnetic material. Examples of the magnetic material contained in the magnetic toner of the present invention include iron oxides such as magnetite and ferrite; metals such as iron, cobalt and nickel, or these metals and aluminum, cobalt, copper, lead, magnesium, tin and zinc; Examples thereof include alloys with metals such as antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, tiran, tungsten and vanadium, and mixtures thereof.

It is desirable that these ferromagnetic materials have an average particle size of about 0.1 to 2 μ, and the amount contained in the toner is about 20 to 200 parts by weight, and particularly preferably 100 parts by weight of the resin component relative to 100 parts by weight of the resin component. It is 40 to 150 parts by weight per part.

Further, the toner of the present invention may be mixed with additives other than the above if necessary. As the additive, for example, Teflon, lubricant such as zinc stearate, or fluidity imparting agent such as colloidal silica, titanium oxide, aluminum oxide, anti-caking agent, or conductivity imparting agent such as carbon black or tin oxide, Alternatively, there are fixing aids such as low molecular weight polyethylene.

To prepare the toner for developing an electrostatic image according to the present invention, the above-mentioned (alkyl) salicylamine chelate charge control agent according to the present invention, a binder resin as described above, and a pigment or dye as a colorant are required. Accordingly, the magnetic materials, additives, etc. are thoroughly mixed by a ball mill or other mixer, and then melted and kneaded by using a heat kneader such as a heating roll, a kneader, an extruder, etc. to make the resins compatible with each other. It is possible to obtain a toner having an average particle diameter of 5 to 20 by dispersing or dissolving a pigment or dye, cooling and solidifying, and then pulverizing and classifying. Alternatively, a method in which the material is dispersed in a binder resin solution and then spray-dried, or a predetermined material is mixed with a monomer to form the binder resin to form an emulsified suspension and then polymerized A method such as a polymerization method for obtaining a toner and a toner manufacturing method can be applied.

Further, as described above, the toner of the present invention can also be obtained by subsequently externally adding the charge control agent to the toner formed by removing all or part of the charge control agent.

The toners produced by these methods can all be used for development to visualize an electrostatic charge image in electrophotography, electrostatic recording, electrostatic printing, etc. by a conventionally known means.

EFFECTS OF THE INVENTION As described above, the toner of the present invention containing an (alkyl) salicylamine chelate as a charge control agent has a uniform positive triboelectric charge amount between toner particles, and the charge amount is easily controlled. Further, the toner is extremely stable without deteriorating during use and the positive triboelectric charge amount does not vary or decrease. Therefore, the above-mentioned obstacles such as the development fog, toner scattering, contamination of the electrophotographic photosensitive material and copying machine are eliminated, and the phenomena of toner aggregation, agglomeration and low temperature fluidity during storage, which have been major problems in the past, are eliminated. The toner is durable against long-term storage, and has excellent abrasion resistance, fixability and adhesiveness of the toner image.

The excellent effect of such a toner is that when it is used in a repetitive transfer type copying system in which the operations of charging, exposing, developing and transferring are continuously repeated, the effect is further expanded. Further, since there is little color tone disorder due to the charge control agent, it is possible to form a color image of excellent color when used as a color electrophotographic toner.

Hereinafter, the present invention will be described more specifically by way of examples.

Example 1 Styrene / butyl acrylate 100 parts Copolymer (80/20) (Weight average molecular weight Mw: about 300,000) Carbon black (Mitsubishi # 44) 10 parts Low molecular weight polyethylene wax 2 parts Salicylamino Co-chelate 2 parts The materials were well mixed with a blender and then kneaded with a two-roll roll heated to 150 ° C. After allowing the kneaded product to cool naturally, it is roughly crushed with a cutter mill, crushed with a fine crusher using a jet stream, and further classified with an air classifier to obtain a toner fine powder having a particle size of 5 to 20 μm. Got

A developer was prepared by kneading 5 parts of the toner with 100 parts of an iron powder carrier having an average particle size of 50 to 80 μm.

Further, the triboelectric charge amount of the toner in the developer was measured by a usual blow-off method.

Then, on the OPC photosensitive member by a conventionally known electrophotographic method,
A negative electrostatic charge image was formed, and this was powder-developed by the magnetic brush method using the above-mentioned developer to form a toner image, which was transferred onto plain paper and heat-fixed. The obtained transfer image has a density of 1.
It was 29, which was sufficiently high, no fog was observed, and there was no toner scattering around the image, and a good image with high resolution was obtained. A transfer image was continuously prepared using the above-mentioned developer, and the durability was examined, but the transfer image after 30,000 sheets was completely achromatic image as compared with the initial image.

Further, during the durability test, the filming phenomenon related to the toner on the photosensitive member was not observed at all, and no problem in the cleaning process was found. Also, at this time, there was no trouble in the fixing process, and at the end of the durability test of 30,000 sheets, the fixing machine was observed, but no scratches or damage on the roller were observed,
There was almost no stain due to the offset toner, and there was no problem in practical use.

Further, when the environmental conditions were 35 ° C. and 85%, the image density was 1.31 which was a value almost unchanged from normal temperature and normal humidity, and a clear image without fog or scatter was obtained and the durability was 30,000. There was almost no change until the number of sheets. Next 15
When a transferred image was obtained at a low temperature of 10% and low humidity of 10%, the image density was as high as 1.29, and solid black was developed and transferred extremely smoothly, and was an excellent image without scattering or voids. A durability test was conducted under these environmental conditions. Copies were made continuously and at intervals, but the density fluctuation was ± 0.2, which was sufficient for practical use up to 30,000 sheets.

Comparative Example 1 Instead of 2 parts of the Co chelate of salicylamine, a Nigrosine dye (Nigrosine Base E manufactured by Orient Chemical Industry) was used.
X) A developer was obtained in the same manner as in Example 1 except that 2 parts was used, and development, transfer and fixing were performed, and an image was similarly obtained. Fog was small at room temperature and normal humidity, but the image density was low at 1.06, line images were scattered, and solid black was noticeable. When the durability was examined, the density decreased to 0.83 at 30,000 sheets.

Further, during the durability test, the toner material formed a thin streak-like film on the surface of the photoconductor from around 10,000 sheets and appeared as lines on the image. This is so-called filming, and it is considered that the charge control agent changes the lubricity of the toner powder.

Further, at the time of endurance, a fixed image was likely to be caught in the fixing roller in the fixing step, and the peeling property from the roller was difficult.

When an image was obtained under the conditions of 35 ° C. and 85%, the image density was as low as 0.88, and fog, scattering, and rubbing increased. The transfer efficiency was as low as 69%.

When an image was obtained under the conditions of 15 ° C. and 10%, the image density was as low as 0.91, and scattering, fog, and rustling were seriously noticeable. Continuous images were output, but 3
The density became 0.53 after about 10,000 sheets, which was not practical.

Example 2 A developer was obtained in the same manner as in Example 1 except that 3 parts of Ni chelate of salicylamine was used instead of 2 parts of Co chelate of salicylamine, and development transfer transfer fixing was performed to obtain an image 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 3 A developer was obtained in the same manner as in Example 1 except that 2 parts of 5-methylsalicylamine Co chelate was used instead of 2 parts of salicylamino Co chelate. Got

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

Example 4 Instead of 2 parts of Co-chelate of salicylamine, 3,5
A developer was obtained in the same manner as in Example 1 except that 2 parts of Fe chelate of -di-t-butylsalicylamine was used, and development, transfer and fixing were performed, and an image was similarly obtained.

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 100 parts (80/20) copolymer (weight average molecular weight Mw: about 300,000) Iron tetraoxide EPT-500 60 parts (manufactured by Toda Kogyo) Low molecular weight polypropylene wax 2 parts Salicylamine Co chelate 2 parts The above materials were well mixed with a blender and then kneaded with a two-roll roller heated to 150 ° C. After allowing the kneaded product to cool naturally, it is roughly crushed with a cutter mill, crushed with a fine crusher using a jet stream, and further classified with an air classifier to obtain a fine powder having a particle size of 5 to 20 μm. It was

Next, 100 parts of the fine powder was mixed with 0.4 part of hydrophobic colloidal silica by a sample mill to prepare a one-component magnetic toner.

The triboelectric charge amount of this toner was measured by a usual blow-off method.

When this toner was applied to a commercially available copying machine (trade name: NP-150Z, manufactured by Canon Inc.) and image formation was performed, the same good results 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 Ni chelate of salicylamino was used instead of 2 parts of Co chelate of salicylamine, and development, transfer,
An image was similarly obtained by fixing.

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

Example 7 In Example 5, in place of 2 parts of the Co-chelate of salicylamine, Co-chelate of 2-methylsalicylamine 2
A developer was obtained in the same manner as in Example 5 except that parts were used, and development, transfer, and fixing were performed, and an image was similarly obtained.

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 benzyldimethyl-hexadecyl ammonium chloride was used instead of 2 parts of the Co chelate of salicylamine in Example 5, and an image was obtained by the same method. . Fog was less at room temperature and normal humidity, but the image density was as low as 0.8 and line drawings were scattered, and solid black was noticeable. I checked the durability, but it was 30,0
At the time of 00 sheets, the temperature dropped to 0.48.

Further, the filming phenomenon at the time of endurance and the problem in the fixing step were almost the same as those in Comparative Example 1 and were not the same.

When an image was obtained under the conditions of 35 ° C. and 85%, the image density was as low as 0.72, and fog, scattering and rubbing increased, and the image was unusable. The transfer efficiency was as low as 63%.

When an image was obtained under the conditions of 15 ° C. and 10%, the image density was as low as 0.73, and scattering, fog, and rubbing were noticeable and transfer bleeding was conspicuous. Continuous images were output, but 3
When the number of sheets was 10,000, the density was 0.59, which was not practical.

Example 8 Styrene / butyl acrylate 100 parts (80/20) copolymer (average molecular weight Mw: about 300,000) Copper phthalocyanine blue pigment 5 parts Low molecular weight polypropylene wax 2 parts Salicylamine Co chelate 2 parts The above material is blended. After mixing well, the mixture was kneaded with two rolls heated to 150 ° C. After allowing the kneaded material to cool naturally, it is roughly crushed with a cutter mill, crushed with a fine crusher using a jet stream, and further classified with an air classifier to obtain a toner fine powder having a particle size of 5 to 20 μm. Obtained.

Further, the triboelectric charge amount of the toner was measured by a usual blow-off method.

Next, 100 parts of the toner was mixed with 50 parts of carrier iron powder having a particle diameter of 50 to 80 μm to obtain a developer.

This developer is stored in the developer container 1 of the developing device shown in the accompanying drawings.
And developed. That is, in this apparatus, a cylindrical toner carrier 2 made of stainless steel whose surface is roughened so as to substantially close the container is housed in the lower opening of the container 1, which has a peripheral speed of 66 m in the direction of arrow a.
It was rotated at m / sec. On the other hand, at the outlet of the container 1 on the downstream side in the rotation direction of the sleeve 2, 200 μm from the sleeve surface
The iron blade 3 having the tip placed at the position is arranged, the fixed magnet 4 is arranged in the sleeve 2, and the main magnetic pole, the N pole, is connected to the center of the sleeve and the center of the sleeve. The blade 3 was arranged so that the angle θ with the tip of the blade 3 was 30 °. Under these conditions, as the sleeve 2 rotates, the magnetic iron powder contained in the developer forms a magnetic brush 5 in the container 1, and the magnetic brush 5 preferentially distributes above the toner. While taking 6 and supplying it to the surface of the sleeve 2, it circulates along the periphery of the sleeve 2 below the container 1 and forms a thin layer 16 of toner on the surface of the sleeve 2 which has passed the blade 3.

In this example, the thickness thus formed is about 80 μ.
dark toner layer -60 on the photosensitive drum 7 facing each other at a developing portion (closest portion) at an interval of about 300 μm and rotating in the direction of arrow b at a peripheral speed of about 60 mm / sec.
A 0V, -1500V negative electrostatic image was developed. At this time, a frequency of 800 Hz and a peak-to-peak value of 1.
A bias voltage of 4 KV and a center value of -300 V was applied between the sleeve 2 and the photosensitive drum 7.

When images were printed out in this way, a good image showing a vivid blue color was obtained, and even after the output of 1500 sheets, even if the toner / carrier ratio became 10 parts / 50 parts, almost no image density was observed. No change was observed, and a good image was obtained even after image formation was performed up to 30,000 sheets while replenishing the toner.

Normal temperature-normal humidity (25 ° C., 60%) in the above Examples and Comparative Examples
The evaluation results under various environmental conditions of RH), high temperature and high humidity (35 ° C., 85% RH), and low temperature and low humidity (15 ° C., 10% RH) are summarized in Tables 1 and 2 below.

[Brief description of drawings]

The drawing is a schematic cross-sectional view of an example of a developing device suitable for applying the toner according to the present invention. 1 ... Developer container, 2 ... Toner carrier, 3 ... Doctor blade, 4 ... Fixed magnet, 5 ... Magnetic brush, 6 ... Toner, 7 ... Electrostatic latent image carrier, 16 ... Thin layer toner.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoji Kawagishi 8-1 Sanrahito-cho, Neyagawa City, Osaka Orient Chemical Industry Co., Ltd. (56) Reference JP-A-59-29259 (JP, A)

Claims (3)

[Claims] 1. Positive friction for developing an electrostatic charge image, comprising a binder resin comprising a styrene-based copolymer, a colorant, and a chelate compound of salicylamine or alkylsalicylamine and iron, nickel or cobalt. Chargeable toner. 2. The electrostatic charge according to claim 1, wherein the chelate compound of salicylamine or alkylsalicylamine is contained in a ratio of 0.1 to 20 parts by weight with respect to 100 parts by weight of the binder resin. Positive friction charging toner for image development. 3. The positive triboelectric toner for developing an electrostatic charge image according to claim 1, wherein the chelate-forming metal is Cu, Ni, Co or Cd.