JP2877550B2 - Positively chargeable magnetic toner, image forming method, image forming apparatus, apparatus unit, and facsimile apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to electrophotography, electrostatic recording,
The present invention relates to a toner used in a developer for developing an electrostatic image such as electrostatic printing.

More specifically, in a direct or indirect electrophotographic developing method, the toner is positively charged to visualize a negative electrostatic image, or a positive electrostatic image is visualized by reversal development. The present invention relates to a positively chargeable magnetic toner exhibiting characteristics and an image forming method, an image forming apparatus, an apparatus unit, and a facsimile apparatus using the positively chargeable magnetic toner.

[0003]

2. Description of the Related Art Conventionally, as an electrophotographic method, for example, US Pat. No. 2,297,691, Japanese Patent Publication No. 42-239
Numerous methods are known as described in Japanese Patent Publication No. 10 and Japanese Patent Publication No. 43-24748. In general, using a photoconductive substance, an electric latent image is formed on a photoreceptor by various means, and then the latent image is developed using toner,
After transferring the toner image to a transfer material such as paper as necessary,
The image is fixed by heating, pressure, heating and pressing, or solvent vapor to obtain a copy.

[0004] As the photoreceptor, conventionally, metal based materials such as amorphous selenium and amorphous silicon, and inorganic compounds such as zinc oxide and cadmium sulfide have been used. However, in recent years, organic optical semiconductors (so-called OPCs) made of azo-based or stilbene-based pigments have been used especially in low-speed machines and popular machines because of their good pressurization, low cost, and high safety. Use in the field is progressing. Further, development in the field of high-speed machines in consideration of improvement in durability and increase in sensitivity has been considered.

[0005] The organic optical semiconductor mainly has a structure in which a carrier transport layer is provided on the photocarrier generation layer from the viewpoints of durability against abrasion, protection of the photocarrier generation layer, and improvement of photosensitivity. At present, most of the carrier transporting layer contains a hole transporting substance. Therefore, since the organic optical semiconductor is negatively charged, a positively charged substance is generally required as a toner. It is.

As a means for making the toner positively chargeable, it is effective to use a compound having an electron donating functional group as a positive charge control agent in the toner. Examples of the positive charge control agent include quaternary ammonium salts and nitrogen-containing organic dyes. Particularly commonly used ones include basic dyes and salts thereof, and specific substances include nigrosine dyes. And triphenylmethane dyes are often used. These positive charge control agents are usually added to a binder resin, melted in a heat-melt kneading step, a pulverizing step and, if necessary, a classification step, and adjusted to an appropriate particle size before use.

However, these commonly used charge control agents are susceptible to changes in charge controllability due to mechanical shock, friction, and changes in environmental conditions such as temperature and humidity. Therefore, when a toner containing these generally used charge control agents is developed using a copying machine, the toner may be deteriorated as the number of copies increases.

In particular, when a dye-based charge control agent is used, the dye is transferred from the toner to the charging member such as a carrier or a developing sleeve due to friction, heat and pressure, making it difficult to charge the toner. It often causes scattering of toner and deterioration of image quality.

[0009] This positively charged magnetic toner also has difficulties on the fixing surface.

There are various methods for fixing a toner image as follows. (1) A method in which toner is heated and melted by radiant heat of a heater to fix the toner on a fixing target. (2) A method in which the toner is caused to flow by pressure to fix the toner to a fixing target. (3) A method of dissolving the toner with a solvent vapor to fix the toner on a fixing object. (4) A method in which the toner is melted and caused to flow by heat and pressure to fix the toner on an object to be fixed.

However, in the fixing method (1), there is a risk of paper jam at the fixing portion of the fixing object and a fire caused by the jam. In the fixing method (2), the material of the toner is considerably limited. It is not universal because the fixing method of (3) pollutes the surrounding environment.
At present, the fixing method (4) is mainly used. The heating and pressure fixing method of (4) is to press the heated roll to the toner image; heat can be efficiently transmitted to the toner even with a relatively low temperature heat source; temperature control can be easily performed; Since the pressure is applied simultaneously with the heat, the deformation of the toner is promoted, and there are many advantages. However, the fixing method (4) also has a problem to be solved. That is, in the fixing method (4), since the surface of the heating / pressing means such as a heat roller and the toner image come into contact with each other under pressure in a molten state, a part of the toner image is transferred to the surface of the fixing roller. This may cause a so-called offset phenomenon, which is re-transferred to the fixing object and stains the image. Severely, a so-called wrapping phenomenon, in which the fixing object adheres to the heat roll, may cause the fixing device to be destroyed. In order to prevent this, a fixing claw is provided in the hot roll fixing device to forcibly separate the fixing target from the hot roll. However, in this case as well, there is a problem that when the winding force on the heat roll is strong, the image of the fixing object is scratched.

From the above, in the heat and pressure fixing method, it is essential to minimize the adhesion of the toner to the heat and pressure means.

For this purpose, the surface of a conventional fixing roll is formed of a material having a low surface energy, such as silicone rubber or fluororesin, which has excellent releasability, and the surface of the fixing roll is further formed of a releasing agent such as silicone oil. A liquid lubricant having good properties is applied. The effect of silicone oil is extremely effective in preventing toner offset and entanglement of the material to be fixed, but it complicates the fixing device, may cause oil stains on the material to be fixed, and may cause heat in the silicone oil. It has further problems such as evaporating and contaminating the inside of the machine, especially the charged wire, and is moving toward the direction of not using it or at least trying to limit its use.

In order to enhance the offset resistance of the toner itself, it is effective to increase the elasticity of the toner at the time of melting to suppress the elongation of the toner. For this purpose, it is necessary to add a rubber-like substance to the toner. The formation of a gel by crosslinking is effective.

In order to improve the releasability of the toner itself, wax such as polyolefin wax such as low molecular weight polyethylene and low molecular weight polypropylene, paraffin wax, wax of ester of long chain aliphatic acid and amide wax is contained in the toner. Is effective.

However, the above measures may not be effective or may have an adverse effect on the positively charged toner. For example, a low surface energy substance such as silicone rubber, fluororesin, or wax tends to have a strong negative charging property when charged, and therefore, when used as a fixing roll, it has a positive polarity on the material to be fixed. It is easy to cause a so-called electrostatic offset phenomenon in which the charged toner is electrostatically offset to the negatively charged fixing roll. Since the low surface energy substance is originally a substance having low dispersibility and low compatibility, when the low surface energy substance is contained in the toner as a release agent, it is easy to form release agent single particles. This is negatively charged, and forms an electrostatic agglomerate with the positively charged toner, sometimes causing black-spotted image stains. A basic dye or a quaternary ammonium salt contained as a positive charge control agent in the positive charge toner contaminates the silicone rubber of the fixing roll, or reacts with fluorine of a fluororesin,
The releasability, elasticity and strength of the fixing roll may be lost. As described above, many improvements have been proposed with respect to the problems relating to the developing properties and the problems relating to the fixing properties specific to the positively chargeable toner.

JP-A-55-134861 and JP-A-56-65417 disclose toners using a binder resin having an acid value. In these documents, by introducing an acid value into a binder resin chain,
Increased intermolecular cohesion of the binder in the toner, increased the adhesive force between the toner and the fixing paper, and increased the interfacial tension between the fixing roll and the surface. ing.

JP-A-57-40264 and JP-A-62-21169 disclose a combination of a binder resin having a thermoplastic resin having an acidic group and a positive charge control agent. In these documents, the toner is stably charged to a positive charge by the ionic stability between the basicity of the charge control agent and the acidity of the binder resin. However, when an acid value is introduced as a positively chargeable toner, there is a problem that developability and durability are reduced. As the number of acid values introduced into the toner binder increases, the negative chargeability becomes stronger, causing the occurrence of reversal fog and lowering of the image density at the time of durability. Therefore, it is difficult to use the toner effectively.

JP-A-57-119364 and JP-A-62-9358 disclose quaternary ammonium sulfate compounds and quaternary ammonium sulfonate compounds. These documents suppress the reaction between a fixing roll made of a vinylidene fluoride-hexafluoropropylene copolymer and a quaternary ammonium salt, and prevent deterioration of a hot roll. However, quaternary ammonium salts are not very powerful as positive charge control agents. Therefore, when the toner is mixed with the carrier particles having a strong negative charge and used, the toner generates practically sufficient tribo.However, in the case of the one-component toner used without being mixed with the carrier particles, the toner is mixed with the carrier particles. It is more difficult to provide sufficient contact than when mixing and using. Therefore, the toner has a drawback that sufficient charge cannot be obtained and the image density is low, and there is a lot of fogging. In particular, the image density is lower under high temperature and high humidity environment conditions.

Attempts have been made to improve the controllability of the charge control agent by combining a quaternary ammonium salt with another positive charge control agent. For example, JP-A-61-1721
No. 55 proposes a combination of a quaternary ammonium salt and nigrosine or a positively chargeable thermoplastic resin. The function of the quaternary ammonium salt here is merely an auxiliary. For use in a one-component magnetic toner used without being mixed with carrier particles, other charge control components combined with the quaternary ammonium salt are used. If the amount is not used as much as the amount required when the other charge control component is used alone, it is insufficient. In such a case, the level of contamination of nigrosine on the charging member still remains.

JP-A-55-113054, JP-A-61-80261 and JP-A-62-2358 disclose a toner having a styrene-butadiene copolymer and a positive charge control agent. It has been disclosed. When a conjugated diolefin such as butadiene is introduced into the molecular chain, the toner has rubber elasticity, which is effective for offset resistance and wrap resistance. When the toner is a positively charged toner, it does not become an obstacle, but rather has the advantage that the toner tribo rises faster, but when a positively charged control agent such as nigrosine is combined with a conjugated diolefin, the toner tends to be overcharged. In addition, there is a problem that compatibility with other resins and charge control agents is poor. In particular, when used as a one-component magnetic toner which is used without being mixed with carrier particles, the dispersion of the magnetic substance is poor and fog may occur.

[0022]

SUMMARY OF THE INVENTION An object of the present invention is to provide a positively chargeable magnetic toner which has solved the above-mentioned disadvantages.

That is, an object of the present invention is to provide a positively chargeable magnetic toner having excellent offset resistance and wrap resistance.

It is a further object of the present invention to provide a positively chargeable magnetic toner having stable charge control properties with little or no change in performance even when used for a long time.

It is a further object of the present invention to provide a positively chargeable magnetic toner having a high image density and capable of forming a clear image with little or no fog.

Still another object of the present invention is to provide an image forming method, an image forming apparatus, an apparatus unit and a facsimile apparatus using the above-mentioned positively chargeable magnetic toner.

[0027]

The positively-chargeable magnetic toner of the present invention is a positively-chargeable magnetic toner having at least a positively-chargeable magnetic toner particle having a binder resin, a magnetic substance and a charge control agent. The binder resin comprises (A) a vinyl polymer having a carboxyl group, an acid group and / or an acid group formed by partial esterification thereof as a polar functional group, and an acid value of 5 to 30; At least a copolymer polymerized by a diolphin-based monomer and a vinyl-based monomer, wherein the charge controllability includes (C) a quaternary ammonium salt and (D) a nigrosine-based dye or a triphenylmethane-based dye; The weight ratio of the above components is defined as 100 with the total amount of component (A) and component (B) being 100
(A): (B): (C): (D) = 80-30: 70-
20: 2.0 to 0.5: 2.0 to 0.1 achieves the above object.

According to the image forming method of the present invention, an electrostatic image carrier carrying an electrostatic image on the surface and a toner carrier carrying a magnetic toner positively charged by friction with the toner carrier on the surface are developed. Forming a developed image by transferring the positively chargeable magnetic toner to the electrostatic image carrier in the developing unit, forming a developed image on the recording material; An image forming method comprising the steps of: transferring with an electric charge having the same polarity as an image; and fixing an unfixed toner image on a transfer material to a recording material by heat and pressure to form an image. Has positively chargeable magnetic toner particles having at least a binder resin magnetic substance and a charge control agent, and the binder resin comprises (A) a carboxyl group, an acid group and / or a partial esterification thereof as a polar functional group. Formed by A vinyl polymer having an acid group and an acid value of 5 to 30; and (B) a copolymer polymerized with at least a diolphin-based monomer and a vinyl-based monomer, wherein the charge controllability is (C) quaternary. It has an ammonium salt and (D) a nigrosine-based dye or a triphenylmethane-based dye, and the weight ratio of the above-mentioned components is (A) assuming that the total amount of the components (A) and (B) is 100:
(B): (C): (D) = 80-30: 70-20:
2.0 to 0.5: 2.0 to 0.1, the positively chargeable magnetic toner is positively charged in a developing section to develop an electrostatic image, and the developed image is transferred to a recording material; The object is achieved by fixing an unfixed toner image on a recording material to form an image.

The image forming apparatus of the present invention has an electrostatic image carrier for carrying an electrostatic image, charging means for charging the electrostatic image carrier, and an image carrier carried on the electrostatic image carrier. Developing means for developing the electrostatic image, transfer means for transferring the developed image developed by the developing means from the electrostatic image carrier to a recording material, and an unfixed image transferred to the recording material. An image forming apparatus having a fixing unit for fixing a toner image to the recording material by heat and pressure, wherein the developing unit includes a positively chargeable magnetic toner particle having at least a binder resin, a magnetic material, and a charge control agent. Having a positively-chargeable magnetic toner and a toner carrier for charging the positively-chargeable magnetic toner to a positive charge by friction with the positively-chargeable magnetic toner,
The binder resin comprises (A) a vinyl polymer having a carboxyl group, an acid group and / or an acid group formed by partial esterification thereof as a polar functional group, and an acid value of 5 to 30; A charge controlling agent having at least a copolymer polymerized by a diolphin-based monomer and a vinyl-based monomer, wherein the charge control agent comprises (C) a quaternary ammonium salt and (D) a nigrosine-based dye or a triphenylmethane-based dye; The weight ratio of the constituent components is (A) :( B), where the total amount of the components (A) and (B) is 100.
(C): (D) = 80-30: 70-20: 2.0-
The above object is achieved by being characterized by a ratio of 0.5: 2.0 to 0.1.

The unit of the apparatus according to the present invention is characterized in that at least one of an electrostatic image carrier for carrying an electrostatic image and a charging means for charging the electrostatic image carrier is provided on the electrostatic image carrier. A unit is formed integrally with the developing means for developing the electrostatic image carried thereon, and the unit forms a unit from the developed image developed by the developing means to the recording material from the electrostatic image carrier. An apparatus body having a transfer unit for transferring, a transfer unit for transferring to the recording material, and a fixing unit for fixing the unfixed toner image transferred to the recording material to the recording material by heat and pressure. A developing unit, the developing unit comprising: a positively chargeable magnetic toner having at least a binder resin, a magnetic substance, and a positively chargeable magnetic toner particle having a charge control agent; and the positively chargeable magnetic toner. The binder resin has a toner carrier for charging the positively chargeable magnetic toner to a positive charge by friction, and the binder resin comprises (A) a carboxyl group, an acid group and / or a partial ester thereof as a polar functional group. A vinyl polymer having an acid group formed by the polymerization, and an acid value of 5 to 30; and (B) at least a copolymer polymerized with a diolphin monomer and a vinyl monomer. (C) a quaternary ammonium salt and (D) a nigrosine-based dye or a triphenylmethane-based dye, and the weight ratio of the constituent components is (A) when the total amount of the components (A) and (B) is 100. ): (B): (C): (D) =
80-30: 70-20: 2.0-0.5: 2.0-
The above object is attained by being characterized by being 0.1.

A facsimile apparatus according to the present invention comprises an electrostatic image carrier for carrying an electrostatic image, charging means for charging the electrostatic image carrier, and an electrostatic carrier carried on the electrostatic image carrier. Developing means for developing the charge image, transfer means for transferring the developed image developed by the developing means from the electrostatic image carrier to a recording material, and an unfixed toner image transferred to the recording material An electrophotographic apparatus having a fixing unit for fixing the recording material by heat and pressure, and a facsimile apparatus having a receiving unit for receiving image information from a remote terminal, the developing unit is at least a binder resin, Positively chargeable magnetic toner having positively chargeable magnetic toner particles having a magnetic material and a charge control agent, and a toner carrier for charging the positively chargeable magnetic toner to a positive charge by friction with the positively chargeable magnetic toner A, the binder resin, (A) a carboxyl group as a polar functional group, acid and / or acid groups formed by their partial esterification, and 5 to 30,
And (B) a copolymer polymerized with at least a diolefin monomer and a vinyl monomer, wherein the charge control agent is (C) a quaternary ammonium salt and (D) It has a nigrosine-based dye or a triphenylmethane-based dye, and the weight ratio of the above components is 100 with the total amount of the component (A) and the component (B) being 100.
(A): (B): (C): (D) = 80-30: 70-
20: 2.0 to 0.5: 2.0 to 0.1 achieves the above object.

The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, it has been found that the use of a specific toner binder resin and a plurality of specific positive charge control agents in combination results in extremely excellent performance. It has been found that a positively chargeable magnetic toner having positively chargeable magnetic toner particles can be obtained.

That is, the binder resin according to the present invention has (A) a polar functional group having a carboxyl group, an acid group and / or an acid group formed by partial esterification thereof, and an acid value of 5 to 30. It is necessary to have a vinyl polymer and (B) at least a copolymer polymerized by a diolefin monomer and a vinyl monomer.

When the acid value is smaller than 5, the electrostatic offset tends to increase and the background fog tends to increase. When the acid value is larger than 30, reversal fog tends to occur, particularly under high-temperature and high-humidity environmental conditions.

The charge control agent according to the present invention needs to have (C) a quaternary ammonium salt and (D) a nigrosine dye or a triphenylmethane dye.

Each component (A) constituting the binder resin and the charge control agent used in the positively chargeable magnetic toner of the present invention,
The content ratios of (B), (C), and (D) in the toner particles are as follows: (A) :( B) :( B) when the total amount of component (A) and component (B) is 100 on a weight basis. C): (D)
= 80-30: 70-20: 2.0-0.5: 2.0-
It must be in the range of 0.1.

When the content ratio of the component (A) in the component (A) and the component (B) as the binder resin in the positively chargeable magnetic toner particles is more than 80% by weight, a predetermined image density is obtained. It takes time to reach, and the tendency of the object to be wrapped around the fixing roll increases. When the content of the component (A) as the binder resin and the component (A) in the component (B) in the positively chargeable magnetic toner particles is less than 30% by weight, a sleeve for frictionally charging the toner is used. And the surfaces of the toner carrier and the fixing roll as described above are contaminated, and this tends to cause ground fog.

When the content ratio of the components (C) and (D) in the positively chargeable magnetic toner particles exceeds one of the upper limits of the above ranges, the toner adheres to the fixing roll and an offset phenomenon occurs. In the case where any one of them is smaller than the lower limit of the above range, the toner cannot be sufficiently charged.

The total amount of the components (C) and (D) was 100 parts by weight based on the total amount of the components (A) and (B) as the binder resin contained in the positively chargeable magnetic toner particles. Sometimes it is preferable to contain 0.6 parts by weight or more,
In this case, sufficient chargeability can be imparted to the toner.

Component (A) of the binder resin used in the present invention
As a monomer unit, for example, acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid,
Dimethyl maleic acid and their acid anhydrides and / or
A homopolymer having the partially esterified product or a copolymer of these with a vinyl monomer can be used.

In the present invention, the acid value is measured in accordance with Japanese Industrial Standard JIS K0076-66 “Test Method for Acid Value of Chemical Products”.

Component (B) of the binder resin used in the present invention
As a monomer unit, for example, butadiene,
Copolymers of diolefins such as isoprene and chloroprene with vinyl monomers are exemplified. Among them, a copolymer of styrene and butadiene is particularly preferred. The copolymerization weight ratio of diolefin and vinyl monomer is 9
It is preferably 0 to 80:10 to 20 in view of compatibility with the component (A).

Specific examples of the monomer species which can be used in the vinyl polymer of the components (A) and (B) contained in the binder resin used in the positively chargeable magnetic toner of the present invention include, for example, styrene, P Styrene such as chlorostyrene and vinyltoluene and its substituted products; for example, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, methacrylic acid Monocarboxylic acid derivatives having a double bond such as octyl, acrylonitrile, methacrylonitrile and acrylamide; dicarboxylic acid derivatives having a double bond such as butyl maleate, methyl maleate, octyl maleate and dimethyl maleate; Vinyl, vinyl acetate, repose Vinyl esters such as vinyl acid; olefins such as ethylene, propylene and butylene; vinyl ketones such as vinyl methyl ketone and vinyl hexyl ketone; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; For example, divinylbenzene, divinylnaphthalene, ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,
Divinyl compounds such as 3-butanediol methacrylate, divinylaniline, divinylether, divinylsulfide and divinylsulfone; and polymers synthesized from these monomer species can be used alone or as a mixture.

As the binder resin according to the present invention, in addition to the above-mentioned polymer, a polymer synthesized from the following monomer species can be used. Specific examples of compounds include phenolic resins, silicone resins, polyester resins, polyurethane resins, polyamide resins, furan resins, epoxy resins, xylene resins, polyvinyl butyral resins, terpene resins, cumarone indene resins, and petroleum resins. Can be

The quaternary ammonium salt of the component (C) used as a charge control agent in the positively chargeable magnetic toner of the present invention includes those represented by the following general formulas (1) and (2).

General formula (1)

[0047]

[Outside 8] In the formula, R ₁ , R ₂ , R ₃ and R ₄ may be the same or different from each other, and may be an alkyl group having 1 to 30 carbon atoms, an aryl group which may have a substituent on an aromatic ring, or Aralkyl group

[0048]

[Outside 9] n represents 1 to 5, Ar represents an aryl group),

[0049]

[Outside 10]

Specific examples of the anion include halo ion, sulfate ion, nitrate ion, borate ion, phosphate ion, organic sulfate ion, organic sulfonate ion, organic phosphate ion, polyacid ion, heteropolyacid ion, Examples include carboxylate ions and tetrafluoroborate.

General formula (2)

[0052]

[Outside 11] In the formula, R ₅ is an alkyl group having 1 to 30 carbon atoms or an aralkyl group having 1 to 30 carbon atoms.

[0053]

[Outside 12] n represents 1 to 5, and Ar represents an aryl group. R ₆ represents an alkyl group having 1 to 10 carbon atoms, and the substituent R ₆ is one or more,

[0054]

[Outside 13]

Specific examples of the anion include a halo ion, a sulfate ion, a nitrate ion, a borate ion, a phosphate ion, an organic sulfate ion, an organic sulfonate ion, an organic phosphate ion, a polyacid ion, a heteropolyacid ion, Examples include carboxylate ions or tetrafluoroborate.

Specific examples of the quaternary ammonium salt are shown below.

[0057]

[Outside 14]

[0058]

[Outside 15]

[0059]

[Outside 16]

The nigrosine dye or triphenylmethane dye of component (D) used in combination with the quaternary ammonium salt of component (C) used as a charge control agent in the positively chargeable magnetic toner of the present invention may be oil. Nigrosine dyes that are soluble or basic nitrogen-containing dyes, nigrosine dyes treated with fatty acids, nigrosine dyes treated with resin acids, or triphenylmethane dyes represented by the following general formula (3): No.

General formula (3)

[0062]

[Outside 36] In the formula, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each the same or different, and each represents a hydrogen, a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. R ₇ , R ₈ and R ₉ each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, which may be the same or different, and A ⁻ represents a nitrate ion, borate ion, phosphate ion, water Anion such as acid ion, organic sulfate ion, organic sulfonate ion, organic phosphate ion, carboxylate ion, organic borate ion or tetrafluoroborate.

Specifically, there are the following.

Specific examples of triphenylmethane dyes are shown below.

[0065]

[Outside 18]

[0066]

[Outside 19]

[0067]

[Outside 20]

[0068]

[Outside 21]

[0069]

[Outside 22]

[0070]

[Outside 23]

The positively-chargeable magnetic toner of the present invention preferably has a fine silica powder. When the positively-chargeable magnetic toner of the present invention has fine silica powder, wear is significantly reduced by the presence of fine silica powder between the toner particles and the sleeve surface. As a result, the life of the positively chargeable magnetic toner and the sleeve is extended, and the toner can maintain a stable chargeability. It is possible to obtain an agent.

As the silica fine powder, either of a dry method or a wet method can be used. However, in consideration of filming resistance and durability, it is preferable to use silica fine powder produced by a dry method.

The dry method referred to here is a method for producing fine silica powder produced by vapor phase oxidation of a silicon halide. For example, a method utilizing the thermal decomposition oxidation reaction of silicon tetrachloride gas in oxygen and hydrogen, and the basic reaction formula is shown below.

SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl

In this manufacturing process, for example, a composite fine powder of silica and another metal oxide can be obtained by using another metal halide such as aluminum chloride or titanium chloride together with a silicon halide. The silicon halide used in the present invention also includes them.

As a method for producing a silica fine powder which can be used in the positively chargeable toner of the present invention by a wet method, various methods generally conventionally known can be applied. For example, the reaction formula of the decomposition of sodium silicon by acid is shown below.

Na ₂ O.XSiO ₂ + HCl + H ₂ O → SiO ₂ .nH ₂ O + HaCl

As another method, (1) sodium silicate is decomposed with an ammonium salt or an alkali salt to form an alkaline earth metal silicate from sodium silicate, and then decomposed with an acid to form a silicate. How to
(2) a method in which a sodium silicate solution is converted into silicic acid using an ion exchange resin; and (3) a method in which natural silicic acid or a silicate is used.

As the silica fine powder, silicates such as anhydrous silicon dioxide (silica), aluminum silicate, sodium silicate, potassium silicate, magnesium silicate and zinc silicate can be used. .

The silica fine powder has a specific surface area by nitrogen adsorption measured by the BET method of 30 m ² / g or more (particularly 50 to 50 m ² / g).
Those within the range of 400 m ² / g) give good results. The silica fine powder is preferably used in an amount of 0.01 to 8 parts by weight based on 100 parts by weight of the magnetic toner particles.
0.1 to 5 parts by weight with respect to parts by weight.

The silica fine powder exhibits an excellent effect when added in an amount of 0.01 to 8 parts by weight, particularly 0.1 to 5 parts by weight, based on 100 parts by weight of the positively charged magnetic toner particles. At times, the toner can more stably obtain positive chargeability.

Preferred forms of the silica fine powder include:
0.1 parts by weight based on 100 parts by weight of the positively chargeable magnetic toner particles.
３3 parts by weight of the silica fine powder is attached to the surface of the toner particles.

The silica fine powder used in the positively chargeable magnetic toner of the present invention for preventing abrasion of the toner and preventing the surface of the sleeve from being stained is more positively charged than negatively charged. This is preferable because charging stability is not impaired.

The method for obtaining the positively chargeable silica fine powder is as follows: the above-mentioned untreated silica fine powder is treated with a silicon oil having an organo group having at least one nitrogen atom in a side chain; a nitrogen-containing silane. There is a method of treating with a coupling agent; or a method of treating with both.

In the present invention, the positively charged paramagnetic silica is
A substance having a positive triboelectric charge with respect to an iron powder carrier when measured by a blow-off method.

As the silicon oil having a nitrogen atom in the side chain used for treating the silica fine powder, a silicon oil having at least a partial structure represented by the following general formula (4) and / or (5) is used. Can be.

Formula (4)

[0088]

[Outside 24] General formula (5)

[0089]

[Outside 25] In the formula, R ₁ represents a hydrogen, an alkyl group, an aryl group or an alkoxy group; R ₂ represents an alkylene group or a phenylene group; R ₃ and R ₄ may be the same or different from each other; Or an aryl group, and R ₅ represents a nitrogen-containing heterocyclic group. The above alkyl group,
The aryl group, alkylene group and phenylene group may have an organo group having a nitrogen atom, or may have a substituent such as halogen as long as chargeability is not impaired.

The nitrogen-containing silane coupling agent used for treating the silica fine powder generally has a structure represented by the following general formula (6).

Formula (6) R _m -Si-Y _{n wherein} R represents an alkoxy group or a halogen atom;
Represents an amino group or an organo group having at least one nitrogen atom, m and n are integers of 1 to 3,
And m + n is 4. )

Examples of the organo group having at least one nitrogen atom used for treating the silica fine powder include an amino group having an organic group as a substituent, a nitrogen-containing heterocyclic group, and a group having a nitrogen-containing heterocyclic group. Can be As the nitrogen-containing heterocyclic group, there is an unsaturated heterocyclic group or a saturated heterocyclic group, and a known one can be used. Specific examples of the unsaturated heterocyclic group are shown below.

[0093]

[Outside 26]

Specific examples of the saturated heterocyclic group are shown below.

[0095]

[Outside 27]

The heterocyclic group used in the present invention is preferably a 5- or 6-membered ring in consideration of stability.

Specific examples of the organo group having at least one nitrogen atom are shown below.

The amino group having an organic group as a substituent includes aminopropyltrimethoxysilane, aminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropylmethoxysilane,
Dibutylaminopropyltrimethoxysilane, monobutylaminopropyltrimethoxysilane, dioctylaminopropyltrimethoxysilane, dibutylaminopropyldimethoxysilane, dibutylaminopropylmonomethoxysilane, dimethylaminophenyltriethoxysilane, trimethoxysilyl-γ-propylphenyl Amines and trimethoxysilyl-γ-propylbenzylamine.

Examples of the nitrogen-containing heterocyclic group or the group having a nitrogen-containing heterocyclic group include trimethoxysilyl-γ-propylpiperidine, trimethoxysilyl-γ-propylmorpholine, and trimethoxysilyl-γ-propylimidazole. Can be

The silica fine powder used in the present invention is reacted or physically adsorbed with the silica fine powder by using a treating agent such as a silane coupling agent, silicon oil and an organosilicon compound for the purpose of hydrophobizing, if necessary. Can be processed. Specific examples of the silane coupling agent and the organosilicon compound for hydrophobizing silica fine powder include, for example, hexamethyldisilazane, vinyltrimethoxysilane, vinyltriethoxysilane, trimethylsilane, trimethylchlorosilane, trimethylsilane. Ethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane,
Bromomethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmethylcaptan, trimethylsilylmercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyl Dimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane, and 2 to 12 siloxane units per molecule; A dimethylpolysiloxane containing a hydroxyl group bonded to one Si is located on each of the units located.

The silicone oil for hydrophobizing the silica fine powder is represented by the following general formula (7).

General formula (7)

[0103]

[Outside 28]

It is preferable to use a silicone oil having a viscosity at 25 ° C. of about 5 to 5000 centistokes. Specific examples of such silicone oil compounds include, for example, methyl silicone oil, dimethyl silicone oil, phenylmethyl silicone oil, chlorophenylmethyl silicone oil, alkyl-modified silicone oil, fatty acid-modified silicone oil, and polyoxyalkylene-modified silicone oil. Can be raised.

The treating agent for hydrophobizing the above silica fine powder can be treated using one kind or a mixture of two or more kinds.

The positively-chargeable magnetic toner of the present invention may further contain a fine powder of a fluorine-containing polymer such as polytetrafluoroethylene, polyvinylidene fluoride and a tetrafluoroethylene-vinylidene fluoride copolymer. preferable. Among them, it is particularly preferable to add polyvinylidene fluoride fine powder in terms of fluidity and abrasiveness. The fluorine-free polymer powder is preferably added in an amount of 0.01 to 2.0 parts by weight, more preferably 0.02 to 1.0 parts by weight, based on 100 parts by weight of the positively chargeable magnetic toner particles. Is to add.

In particular, the positively-chargeable magnetic magnetic toner in which the finely-divided silica powder and the fine powder of the fluorine-containing polymer are combined with the positively-chargeable magnetic toner particles is not clear, but the fine silica particles adhered to the toner particles are not clearly understood. For example, the silica fine powder attached to the toner particles is not released from the toner particles to reduce the effect on toner abrasion and sleeve fouling; and the charging stability of the toner is reduced. Can be further increased.

The magnetic positively chargeable magnetic toner of the present invention may have other additives as necessary. Other additives include abrasives such as, for example, cerium oxide and silicon carbide, fluidity-imparting and anti-caking agents such as, for example, aluminum oxide, and conductivity-imparting agents, such as, for example, carbon black and tin oxide.

The positively-chargeable magnetic toner of the present invention is, for example, a low-molecular-weight polyethylene, a low-molecular-weight polypropylene, a microcrystalline wax, a carnauba wax, a sazol wax, or a paraffin wax for the purpose of improving the releasability at the time of hot roll fixing. It may have a waxy substance. The wax-like substance is preferably added in an amount of about 0.5 to 5% by weight in the positively-chargeable magnetic toner particles.

Examples of the magnetic material used in the positively chargeable magnetic toner of the present invention include iron oxide such as magnetite; iron oxide containing other metal oxides such as ferrite; metals such as Fe, Co and Ni; And Al, Co, Cu, Pb,
Mg, Ni, Sn, Zn, Sb, Be, Bi, Cd, C
alloys with metals such as a, Mn, Se, Ti, W, V;
And mixtures thereof.

These magnetic materials have an average particle size of about 0.1 to about 2 μm.

[0112]

[Outside 29] The saturation magnetization is 50 to 200 emu / g (more preferably 5
0 to 100 emu / g), and the remanent magnetization is 2 to
Those having 20 emu / g are preferred.

The magnetic substance is added to the positively-chargeable magnetic toner particles in a total amount of 100% of the components (A) and (B) of the binder resin.
It is preferably contained in an amount of 20 to 150 parts by weight, more preferably 40 to 120 parts by weight based on parts by weight.

In the present invention, the positively chargeable magnetic toner is
It has a positive triboelectric charge with respect to the iron powder carrier when measured by a blow-off method.

Hereinafter, the measuring method of the present invention will be described.

Measurement of triboelectric charge: The measurement method will be described in detail with reference to the drawings.

FIG. 1 is an explanatory view of an apparatus for measuring the triboelectric charge of toner and silica. A sample whose triboelectric charge is to be measured in a metal measuring container 2 having a 500-mesh screen 3 at the bottom; this sample is a mixture of toner and iron powder carrier in a weight ratio of 1: 9, or a mixture of silica and iron powder carrier. 50 to 100 ml of a mixture having a weight ratio of 1:99
The mixture (developer) obtained by shaking by hand for about 10 to 40 seconds in a volume polyethylene bottle;
5 to about 1.5 g are put and a metal lid 4 is formed. At this time, the entire weight of the measuring container 2 having the sample is weighed and W
₁ (g). Next, in the suction device 1 (at least the portion in contact with the measurement container 2 is an insulator), the suction is performed through the suction port 7 and the air volume control valve 6 is adjusted to reduce the pressure of the vacuum gauge 5 to 25.
Adjust to 0 mmAq. This condition is sufficient, preferably 2
The toner or silica is removed by suction for a minute. The potential of the electrometer 9 at this time is set to V (volt). Here, reference numeral 8 denotes a capacitor, whose capacity is C (μF). The total weight of the measuring container 2 after the suction is weighed and defined as W ₂ (g).
The triboelectric charge (μc / g) of the toner or silica is calculated as follows.

[0118]

[Outside 30] The measurement conditions are a temperature of 23 ° C. and a temperature of 60% RH, and EFV200 / 300 (made by Powder Tech) is used as the iron powder carrier used for the measurement.

An image forming method and an image forming apparatus according to the present invention will be described with reference to FIGS.

Reference numeral 12 denotes a charger as charging means for charging the photosensitive drum 11 as an electrostatic image carrier. Reference numeral 25 denotes a power supply unit for applying a voltage to the charger 12, and supplies a predetermined voltage to the charger. Reference numeral 13 denotes a transfer charger as a transfer unit. A predetermined bias is applied from the constant voltage power supply 24 to the transfer charger. The bias conditions are preferably such that the current value is 0.1 to 50 μA and the voltage value (absolute value) is 500 to 4000 V.

The surface of the OPC photosensitive member is charged, for example, to a negative polarity by a charger 12 as a charging means having a power supply section (voltage applying means) 25, and an exposed electrostatic latent image is formed by light image exposure as a latent image forming means. Form. The latent image is formed by the positively-charged magnetic toner 20 of the present invention held in a developing device 19 provided with an iron magnetic blade 21 and a non-magnetic developing sleeve 14 as a toner carrier containing a magnet 140. develop. The developing sleeve 14 is a stainless sleeve (SUS30) having a plurality of spherical trace depressions having a diameter of 50 mm.
Use 4). A bias applying means 2 is provided between the conductive sleeve of the photosensitive drum 11 and the developing sleeve 14 in the developing section.
2, an alternate bias, a pulse bias and / or a DC bias are applied. The transfer paper P is transported,
When it comes to the transfer section, the charged image is charged by the voltage applying means 24 from the back surface (the surface opposite to the photosensitive drum side) of the transfer paper P by the transfer charger 13 so that the developed image (toner image) on the surface of the photosensitive drum 11 is formed. The image is electrostatically transferred onto the transfer paper P. The transfer paper P separated from the photosensitive drum 11 is subjected to a fixing process to fix a toner image on the transfer paper P by a heating / pressing roller fixing device 17.

The positively-chargeable magnetic toner 20 remaining on the photosensitive drum 11 after the transfer step is removed by a cleaning device 18 having a cleaning blade. After the cleaning process, the photosensitive drum 11 is gradually charged by the erase exposure 16, and the process starting from the charging process by the charger 12 is repeated again.

The photosensitive drum 11 has an OPC photosensitive layer and a conductive substrate, and moves in the direction of the arrow. A non-magnetic cylindrical developing sleeve 14 serving as a toner carrier rotates so as to advance in the same direction as the surface of the photosensitive drum 11 in the developing section. Inside the developing sleeve 14, a multi-pole permanent magnet 140 (magnet roll) as a magnetic field generating means is arranged so as not to rotate. The multipole permanent magnet 140 has a magnetic field N ₁ = 500 to
900 gauss, magnetic pole N ₂ = 600-1100 gauss, magnetic pole S ₁ = 800-1500 gauss, and magnetic pole S ₂ = 4
It is preferable to set it to 00 to 800 Gauss. Developing device 1
The positively chargeable magnetic toner 20 in 9 is applied to the developing sleeve 14, and a positive triboelectric charge is given to the positively chargeable magnetic toner 20 by friction between the surface of the developing sleeve 14 and the positively chargeable magnetic toner 20. Further, by arranging the iron magnetic doctor blade 21 close to the cylindrical surface of the developing sleeve 14 (interval: 50 μm to 500 μm) and opposed to one magnetic pole position of the multipole permanent magnet 140, the thickness of the toner layer 200 is reduced. Thin (30 μm to 300 μm)
μm) and uniformly regulate the toner layer 20 to be thinner than the gap between the photosensitive drum 11 and the developing sleeve 14 in the developing section.
0 is formed so as not to contact the photosensitive drum 11. The rotation speed of the developing sleeve 14 is adjusted so that the surface speed of the developing sleeve 14 is substantially the same as or close to the speed of the surface of the photosensitive drum 11. The opposed magnetic poles may be formed by using permanent magnets instead of iron as the magnetic doctor blades 21. In the developing section, an AC bias or a pulse bias may be applied between the developing sleeve 14 and the surface of the photosensitive drum 11 from a bias power supply 22 as bias means. As the bias conditions, it is preferable that Vpp = 1500 to 2300 V as an AC bias, f = 900 to 1600 (Hz), and DC = −100 to −350 V as a DC bias. Developing sleeve (toner carrier) 14
When the toner 20 is transferred at the developing portion formed at the nearest portion and the vicinity of the photosensitive drum 11, the electrostatic force of the electrostatic image bearing surface of the photosensitive drum 11, and the action of the AC bias or the pulse bias As a result, the toner 20 is transferred to the photosensitive drum 11 while reciprocating between the developing sleeve 14 and the photosensitive drum 11.

Instead of the magnetic doctor blade 21 as a toner layer regulating member, an elastic blade made of an elastic material such as silicon rubber is used, and the elastic blade is pressed against the surface of the photosensitive drum 11 to thereby form the toner layer 2.
The toner layer having a predetermined layer thickness may be formed on the developing sleeve 14 by regulating the layer thickness of the toner layer 00.

As the photosensitive drum 11, instead of the OPC photosensitive drum, an insulating drum for electrostatic recording, α-Se, CdS, Z
A photosensitive drum having a photoconductive insulating material layer such as nO ₂ and α-Si can be appropriately selected and used in accordance with development conditions.

As the image forming apparatus, a plurality of components such as the photosensitive drum (electrostatic image carrier) developing means, the charging means, and the cleaning means described above are integrally combined as an apparatus unit. This device unit may be configured to be detachably attached to the device body. For example, a unit is formed by integrally supporting at least one of the charging unit, the developing unit, and the cleaning unit together with the photosensitive drum, and is attached to and detached from the apparatus main body by using a guide unit such as a rail of the apparatus main body. It may be configured to be freely mounted. At this time, the above-described device unit may be provided with a charging unit and / or a developing unit.

When the image forming apparatus of the present invention is used as a facsimile printer, the optical image exposure 15 as a latent image forming means is a digital exposure using a laser beam for printing received data. One specific example of this case is shown in the block diagram of FIG.

The controller 211 controls the image reading unit 210 and the printer 219. The whole controller 211 is controlled by the CPU 217. The read data from the image reading unit is transmitted to the partner station through the transmission circuit 213. Data received from the partner station is sent to the printer 219 through the receiving circuit 212. Predetermined image data is stored in the image memory. Printer control 2
Reference numeral 18 controls the printer 219. 214 is a telephone.

The image received from the line 215 (image information from the remote terminal connected via the line) is demodulated by the receiving circuit 212, and then the CPU 217 performs a decoding process of the image information. Is stored in When the image of at least one page is stored in the memory 216, the image of the page is recorded. CPU 217
Reads out one page of image information from the memory 216 and sends the decoded one page of image information to the printer controller 218. The printer controller 218
Upon receiving one page of image information from the CPU 218, the CPU 218 controls the printer 219 to record the image information of the page.

The CPU 217 receives the next page during recording by the printer 219.

As described above, image reception and recording are performed.

[0132]

The present invention will be described in more detail with reference to the following examples, which do not limit the present invention in any way. All parts in the examples are parts by weight.

Example 1 Styrene / n-butyl acrylate / n-butyl maleate / divinylbenzene copolymer (copolymerization weight ratio = 7)
4.5 / 22.0 / 3.0 / 0.4, acid value = 9.5, M
60 parts ・ Low molecular weight polyethylene (Mw = 1300) 4 parts ・ Styrene / butadiene / divinylbenzene copolymer (copolymerization weight ratio = 86/14 / 0.4) 40 parts ・ Magnetic iron oxide 70 parts

[0134]

[Outside 31] ・ Nigrosine dye (charge control agent) 0.5 parts

After the above materials are mixed well with a Hensiel mixer, they are kneaded with an extruder set at 100 ° C. After cooling the kneaded product, the mixture was coarsely pulverized by a cutter mill, and then finely pulverized by a jet mill using a jet stream.
Finely pulverized fine particles are classified by an air classifier, and the average particle size is 1
A black fine powder (positive chargeable magnetic toner particles) of 2.5 μm was obtained. The tribo value of the obtained black fine powder (magnetic toner particles) was +7.5 μc / g. Further, 100 parts of the obtained black fine powder was treated with amino-modified silicone oil (viscosity at 25 ° C .: 100 cp, amine equivalent: 800) to obtain positively charged hydrophobic dry silica (BET specific surface area: 1).
30 m ^{2 /} g) 0.2 spherical polyvinylidene fluoride (PVDF) particles having 0.4 parts and an average particle size of 0.2 μm
Were added and mixed with a Hensiel mixer to obtain a magnetic toner. The tribo value of the obtained magnetic toner was +6.0 μc /
g.

The image of the positively chargeable magnetic toner was image-processed with a commercially available electronic copying machine NP-5540 (manufactured by Canon Inc.) as shown in FIG.
The image density was unchanged after copying 100,000 sheets.

The developing conditions at this time are as follows.

Bias conditions in the developing section: AC voltage = 1500 Vpp, AC frequency = 1600 Hz, DC voltage = −250 V Spacing between magnetic blade and toner carrier: 250 μm Thickness of toner layer on toner carrier: about 180 μm Bias condition in transfer means: current value 400 mA,
Voltage = −5.6 KV Magnetic condition of magnet of toner carrier: N ₁ = 820 gauss, N ₂ = 600 gauss, S ₂ = 700 gauss, S ₂ = 6
00 Gauss ・ Process speed: 40 sheets / min

Further, a background portion and an inversion portion (in order to perform multiplex copying, a strong auxiliary light is partially applied to the photosensitive drum, and the light portion potential of the portion of the photosensitive drum is changed to the light portion potential of a normal blank portion of the photosensitive drum. The fogging phenomenon was not recognized in any of the portions where the negative potential was lowered), and there was little jumping. Further, under a low humidity condition of a temperature of 15 ° C./humidity of 10% RH and a high humidity condition of a temperature of 32.5 ° C./85% RH,
The image density was 1.3 or more, and good results were obtained.

No contamination was observed on the surface of the heat roll made of PFA (perfluoroalcoholate), and no contamination due to offset was observed on the image. In addition, the entire solid black image was formed and fixed.However, there was no occurrence of a phenomenon such as jam caused by the recording material being wrapped around the heat roll by a strong adhesive force, and the heat roll fixing device formed on the image. No scar due to the provided fixing claw was found.

Example 2 The same procedure as in Example 1 was carried out except that the combination of the charge control agents used in Example 1 was changed to the following charge control agent combinations.

Quaternary ammonium salts (charge control agents)

[0143]

[Outside 32] ・ Basic dye (charge control agent)

[0144]

[Outside 33] The tribo value of the obtained black fine powder (magnetic toner particles) is +
The magnetic toner having positively charged hydrophobic dry silica and spherical polyvinylidene fluoride particles had a tribo value of +9.5 μc / g.

Temperature 23.5 ° C./humidity 60% RH, temperature 3
2.5 ° C / 85% RH and temperature 15 ° C / humidity 10
As a result of producing 100,000 sheets under each environmental condition of% RH, the image density was always 1.30 or more, and no fog was observed. Neither offset to the image nor stain on the fixing roll was observed.

Furthermore, the winding resistance was good.

Example 3 Styrene / 2-ethylhexyl acrylate / n-butyl maleate / divinylbenzene copolymer (copolymer weight ratio = 70 / 27.7 / 1.5 / 0.8, acid value = 5, M
w = 380,000) 70 parts styrene / butadiene copolymer (copolymer weight ratio = 85)
/ 15) 30 parts ・ Low molecular weight propylene / ethylene copolymer (Mw600
0) 4 parts-Magnetic iron oxide powder 60 parts-Quaternary ammonium salt (charge control agent)

[0148]

[Outside 34] ・ Nigrosine dye (charge control agent) 1.0 part

Using the above materials, the same procedure as in Example 1 was carried out. The tribo value of the obtained fine black powder (magnetic toner particles) was +9.0 μc / g, and the obtained positively-chargeable hydrophobic dry powder was dried. The tribo value of the magnetic toner having silica and spherical polyvinylidene fluoride particles was +7.5 μc / g. Temperature 23.5 ° C / humidity 60% RH, temperature 32.5 ° C
/ RH 85% RH, and temperature 15 ° C / humidity 10% RH
As a result, 100,000 sheets of images were output under each of the environmental conditions described above. As a result, the image density was always 1.30 or more, and no fog was observed. Neither the offset to the image nor the stain on the fixing roll was observed. Furthermore, the winding resistance was good.

Example 4 In Example 1, the copolymer weight ratio of the vinyl polymer having an acid value to the styrene / butadiene / divinylbenzene copolymer was 30/70 / 0.4.
Was performed in the same manner as in Example 1 except that the tribo value of the obtained black fine powder (magnetic toner particles) was +8.0.
μc / g, and the tribo value of the obtained magnetic toner having positively charged hydrophobic dry silica and spherical polyvinylidene fluoride particles was +7.0 μc / g. Temperature 2
3.5 ° C / 60% RH, temperature 32.5 ° C / 85 humidity
As a result, 100,000 sheets were imaged under the respective environmental conditions of% RH and a temperature of 15 ° C./humidity of 10% RH. As a result, the image density was always 1.30 or more, and no fog was observed. No offset to the image and no stain on the fixing roll were observed. Furthermore, the winding resistance was good.

Comparative Example 1 The procedure of Example 1 was repeated, except that the styrene / butadiene copolymer was not used and the vinyl polymer having an acid value was changed to 100 parts.

The tribo value of the obtained black fine powder (magnetic toner particles) is +7.5 μc / g, and the tribo value of the magnetic toner having the positively charged hydrophobic dry silica and spherical polyvinylidene fluoride particles is as follows. Was +5.5 μc / g. The initial image density is less than 1.00 and 1,0
The image density reached 1.25 only after the image was formed on 00 sheets, but a lot of fog occurred in the reversal portion. Temperature 32.
Under the environmental conditions of 5 ° C./85% RH, the image density at the time of printing 1,000 sheets does not exceed 1.10 and the temperature is 1
Under the environmental conditions of 5 ° C. and 10% RH, the fogged image was generated as a whole when 1,000 images were printed.

Although the offset to the image was almost negligible, the wrapping force around the fixing roll was strong, and scars were observed on the image due to the fixing separation claw provided in the hot roll fixing device.

[Comparative Example 2] The procedure of Example 1 was repeated, except that the following copolymer was used instead of the vinyl polymer having an acid value.

Styrene / n-butyl acrylate / divinylbenzene copolymer (copolymer weight ratio = 77.5 / 22.0 / 0.4, acid value =
0, Mw = 320,000) 60 copies

The tribo value of the obtained black fine powder (magnetic toner particles) is +11.0 μc / g, and the tribo value of the magnetic toner having the positively charged hydrophobic dry silica and spherical polyvinylidene fluoride particles is as follows. Is +11.5 μc /
g.

The image density was 1.20, and an image having a lot of background fog was formed.
Under the environmental condition of H, the toner aggregates on the developing sleeve,
Non-uniformity occurred in toner application.

The image was slightly stained by offset. Further, a scar on a white line of 1 to 2 cm was sometimes formed on the image by a fixing separation claw provided in a hot roll fixing device.

[Comparative Example 3] The same operation as in Example 2 was carried out except that no quaternary ammonium salt was contained.

The tribo value of the obtained black fine powder (magnetic toner particles) is +9.0 μc / g, and the tribo value of the magnetic toner having the positively charged hydrophobic dry silica and spherical polyvinylidene fluoride particles is as follows. Was +8.0 μc / g.

The formed image had a lot of background fog, the image density was as low as about 1.10, and the image density when 2,000 sheets were imaged was 1.0 or less.

At this time, when the developing sleeve was cleaned with a solvent, the image density was restored to 1.10. From this, it was found that the decrease in image density was caused by contamination.
When 20,000 sheets of images were output, the fixing roll was stained by the toner, and the offset resistance was deteriorated.

[Comparative Example 4] The same operation as in Example 1 was carried out except that no nigrosine dye was contained.

The tribo value of the obtained black fine powder (magnetic toner particles) was +7.0 μc / g, and the tribo value of the magnetic toner having the positively chargeable hydrophobic dry silica and spherical polyvinylidene fluoride particles was obtained. Was +5.0 μc / g.

The image density of the formed image was 1.0 or less, and fogging occurred. Temperature 32.5 ° C / humidity 85
Under the environmental conditions of% RH, the image density was as low as 0.6.

Comparative Example 5 The procedure of Example 1 was repeated, except that the vinyl copolymer having an acid value was not used and the styrene / butadiene / divinylbenzene copolymer was 100 parts. Was.

The tribo value of the obtained black fine powder (magnetic toner particles) was +9.0 μc / g, and the tribo value of the obtained magnetic toner having positively charged hydrophobic dry silica and spherical polyvinylidene fluoride particles was obtained. Was +8.5 μc / g.

The formed image had an image density of 1.2 or less and had an extremely large amount of background fog. Temperature 2
Even under the environmental conditions of 3.5 ° C./60% RH, the toner was unevenly applied on the sleeve.

Example 5 The procedure of Example 1 was repeated except that the vinyl polymer having an acid value was changed to the following copolymer.
Performed in the same manner as in Example 1. Styrene / n-butyl acrylate / n-butyl maleate / divinylbenzene copolymer (copolymerization weight ratio = 7
0.0 / 21.5 / 8.0 / 0.4, acid value = 28, Mw
= 300,000) 60 copies

The tribo value of the obtained black fine powder (magnetic toner particles) was +6.5 μc / g, and the tribo value of the magnetic toner having the positively chargeable hydrophobic dry silica and spherical polyvinylidene fluoride particles was obtained. Was +5.0 μc / g.

Temperature 23.5 ° C./humidity 60% RH, temperature 3
2.5 ° C / 85% RH, and 15 ° C / 10 humidity
As a result of producing 100,000 sheets under each environmental condition of% RH, the image density was always 1.25 or more, and no fog was observed. No offset to the image and no stain on the fixing roll were observed. Furthermore, the winding resistance was good.

[Comparative Example 6] The procedure of Example 5 was repeated, except that the vinyl copolymer having an acid value in Example 5 was replaced with the following copolymer having a higher acid value.

Styrene / n-butyl acrylate / n-butyl maleate / divinylbenzene copolymer (copolymer weight ratio = 69.0 / 20.0 / 10.5 / 0.4, acid value = 37, (Mw = 280,000) 60 parts The obtained fine black powder (magnetic toner particles) has a tribo value of +
The tribo value of the obtained magnetic toner having positively charged hydrophobic dry silica and spherical polyvinylidene fluoride particles was 6.0 μc / g, and the tribo value was +4.0 μc / g. The image density of the formed image was as low as 1.0, and fogging occurred.

[Comparative Example 7] In Example 1, the contents of the quaternary ammonium salt and the nigrosine dye were each adjusted to 2.0.
The same operation as in Example 1 was performed except that the ratio was changed to /2.5.

The tribo value of the obtained black fine powder (magnetic toner particles) was +9.0 μc / g, and the tribo value of the magnetic toner having the positively chargeable hydrophobic dry silica and spherical polyvinylidene fluoride particles was obtained. Was +8.0 μc / g. Smear due to offset was slightly observed on the formed image.

[Comparative Example 8] In Example 1, the contents of the quaternary ammonium salt and the nigrosine dye were each adjusted to 0.2.
The same operation as in Example 1 was performed except that the ratio was changed to /0.1.

The tribo value of the obtained black fine powder (magnetic toner particles) is +8.5 μc / g, and the tribo value of the obtained magnetic toner having positively charged hydrophobic dry silica and spherical polyvinylidene fluoride particles. Was +6.0 μc / g.

Under environmental conditions of a temperature of 23.5 ° C./humidity of 60% RH and a temperature of 15 ° C./humidity of 10% RH, 1.25 is obtained.
Image density of 32.5 ° C./85% humidity
Under the RH environmental conditions, the image density was sometimes lower than 1.20. Further, when an image was formed after the toner was left overnight under the environmental conditions, the image density was lower than 1.0. Under environmental conditions of a temperature of 32.5 ° C. and a humidity of 85% RH, stains on the image due to offset occurred.

Comparative Example 9 Example 1 was repeated except that the following copolymer was used in place of the vinyl copolymer having an acid value and the styrene / butadiene / divinylbenzene copolymer used in Example 1. The same was done.

A styrene / n-butyl accelerator / divinylbenzene copolymer (copolymerization weight ratio = 77.5 / 2)
2.0 / 0.4, acid value = 0, Mw = 320,000) 100 parts

The tribo value of the obtained black fine powder (magnetic toner particles) was +9.5 μc / g, and the tribo value of the magnetic toner having the positively chargeable hydrophobic dry silica and spherical polyvinylidene fluoride particles was obtained. Was +8.0 μc / g. The image density of the formed image was slightly lower, such as 1.0 to 1.2, and sometimes became 1.0 or less under environmental conditions of a temperature of 32.5 ° C. and a humidity of 85% RH. Temperature 15 ℃
Image density under environmental conditions of 10% RH / 1.1%
1.2, and fog occurred significantly. Further, when image formation was performed without replenishing toner, the density was reduced, and the image density was reduced to about 0.6.

Comparative Example 10 Comparative Example 9 was carried out in the same manner as in Comparative Example 9, except that the amount of nigrosine was changed to 2.0 parts.

The tribo value of the obtained black fine powder (magnetic toner particles) is +10.5 μc / g, and the tribo value of the magnetic toner having the positively charged hydrophobic dry silica and spherical polyvinylidene fluoride particles is as follows. Is +9.5 μc / g
Met. Although the image density of the formed image was 1.2 or more, the phenomenon sleeve was dyed blue when continuous image formation was performed. There was not much decrease in density during image output,
When the image output was interrupted for one day or more, the image density decreased by 0.1 or more with respect to the image density before the interrupt. Temperature 32.5
Under the environmental conditions of 85 ° C./humidity of 85% RH, the image density did not readily recover to the image density before the interruption after the above interruption, and the image became fogged as a whole.

Comparative Example 11 The procedure of Example 1 was repeated, except that the vinyl copolymer having an acid value was changed to the following vinyl copolymer.

Styrene / n-butyl acrylate / n-butyl maleate / divinylbenzene copolymer (copolymerization weight ratio = 75 / 23.5 / 0.8 / 0.7, acid value = 2.
5, Mw = 380,000) 60 copies

The tribo value of the obtained black fine powder (magnetic toner particles) is +8.5 μc / g, and the tribo value of the magnetic toner having the positively charged hydrophobic dry silica and spherical polyvinylidene fluoride particles is as follows. Was +8.5 μc / g.

Initially, the image density of the formed image is 1
It was 30 or more, had a good rise and had sufficient performance. When endured, fog tended to occur slightly, especially under low-humidity environmental conditions.

On the image, the contamination due to the offset was very small and practically no problem, but some scars were generated by the fixing / separating nail.

[0189]

As described above, the positively charged magnetic toner of the present invention has the above-described structure, and thus has excellent anti-offset and anti-winding properties due to the action of the binder resin, and has a long time due to the action of the charge control agent. It has stable charge controllability even when used, has a high image density, and can form a clear image without fog.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an apparatus for measuring a triboelectric charge amount of a toner in a triboelectric charge amount measurement.

FIG. 2 is a schematic configuration diagram showing a specific example for explaining an image forming method and an image forming apparatus of the present invention.

FIG. 3 is a partially enlarged view of FIG. 2 for explaining a developing step.

FIG. 4 is a block diagram of a facsimile apparatus using the electrophotographic apparatus as a printer.

[Explanation of symbols]

 REFERENCE SIGNS LIST 11 electrostatic image carrier 12 charging means 13 transfer charger 14 toner carrier 15 latent image forming means 16 erase exposure 17 fixing means 18 cleaning means 19 developing device 20 positively chargeable magnetic toner 21 toner layer regulating member

Continuing on the front page (72) Inventor Masaji Fujiwara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Masayoshi Shimamura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-2-135368 (JP, A) JP-A-1-259371 (JP, A) JP-A-3-7948 (JP, A) JP-A-59-136747 (JP, A) JP-A-62-9358 (JP, A) JP-A-51-11455 (JP, A) JP-A-2-123372 (JP, A) JP-A-3-229263 (JP, A) JP-A-57-40264 (JP, a) JP Akira 56-65147 (JP, a) JP flat 3-26057 (JP, a) JP Akira 62-201467 (JP, a) (58 ) investigated the field (Int.Cl. ⁶ , DB name) G03G 9/087 G03G 9/097

Claims (40)

(57) [Claims] 1. A positively chargeable magnetic toner having positively chargeable magnetic toner particles having at least a binder resin, a magnetic substance and a charge control agent, wherein the binder resin comprises (A) a carboxyl group as a polar functional group, Group and / or an acid group formed by partial esterification thereof, and a vinyl polymer having an acid value of 5 to 30 and (B) a copolymer polymerized by at least a diolefin monomer and a vinyl monomer Wherein the charge control agent comprises (C) a quaternary ammonium salt and (D)
It has a nigrosine-based dye or a triphenylmethane-based dye, and the weight ratio of the components is as follows: component (A) and component (B)
(A): (B): (C):
(D) = 80-30: 70-20: 2.0-0.5:
A positively chargeable magnetic toner having a ratio of 2.0 to 0.1. 2. The component (A) is a monomer selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid and dimethylmaleic acid, their acid anhydrides and their partially esterified products. 2. The positively chargeable magnetic toner according to claim 1, comprising a homopolymer having the formula or a copolymer having the monomer and a vinyl monomer. 3. The positively chargeable magnetic toner according to claim 1, wherein said component (B) has a copolymer having a diolefin monomer and a vinyl monomer. 4. The component (C) is represented by the following general formula: (Wherein R ₁ , R ₂ , R ₃ and R ₄ are each the same,
Which may be different, an alkyl group having 1 to 30 carbon atoms,
Aryl or aralkyl group which may have a substituent on the aromatic ring n represents 1 to 5, and Ar represents an aryl group). The positively-chargeable magnetic toner according to claim 1, further comprising a quaternary ammonium salt represented by the following formula: 5. The component (C) is represented by the following general formula: (Wherein, R ₅ is an alkyl group having 1 to 30 carbon atoms or an aralkyl group having 1 to 30 carbon atoms.) n represents 1 to 5, and Ar represents an aryl group. And R ₆ represents an alkyl group having 1 to 10 carbon atoms, and the number of the substituents R ₆ is one or more. The positively-chargeable magnetic toner according to claim 1, further comprising a quaternary ammonium salt represented by the following formula: 6. The component (D) has the following general formula: (Wherein, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ may be the same or different from each other, and may be a hydrogen, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. And R ₇ , R ₈ and R ₉ each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group which may be the same or different from each other, and A ⁻ represents an anion.) The positively chargeable magnetic toner according to claim 1, further comprising a dye. 7. The anion is a nitrate ion, borate ion, phosphate ion, hydroxyl ion, organic sulfate ion, organic sulfonate ion, organic phosphate ion, carboxylate ion, organic borate ion or tetrafluoro ion. 7. The positively chargeable magnetic toner according to claim 6, wherein the toner is borate. 8. The method according to claim 1, wherein the component (D) comprises a compound selected from the group consisting of a nigrosine dye, a nigrosine dye treated with a fatty acid, and a nigrosine dye treated with a resin acid. Positively chargeable magnetic toner. 9. A developing unit comprising: an electrostatic image carrier which carries an electrostatic image on its surface; and a toner carrier which carries magnetic toner positively charged by friction with the toner carrier on its surface at a predetermined interval in a developing unit. Forming a developed image by transferring the positively chargeable magnetic toner to the electrostatic image carrier in the developing section, and forming the formed developed image on a recording material having the same polarity as the electrostatic image. An image forming method comprising: transferring by an electric charge; and fixing an unfixed toner image on a transfer material to a recording material by heat and pressure to form an image, wherein the positively chargeable magnetic toner comprises at least a binder resin. The binder resin comprises (A) a carboxyl group, an acid group, and / or an acid formed by partial esterification thereof as a polar functional group. Moto and 5ino A vinyl polymer having an acid value of 30 and (B) at least a copolymer polymerized with a diolefin monomer and a vinyl monomer, wherein the charge control agent is (C) a quaternary ammonium salt and (C) D)
It has a nigrosine-based dye or a triphenylmethane-based dye, and the weight ratio of the components is as follows: component (A) and component (B)
(A): (B): (C):
(D) = 80-30: 70-20: 2.0-0.5:
2.0 to 0.1, wherein the positively chargeable magnetic toner is positively charged in a developing unit to develop an electrostatic image, transfer a developed image to a recording material, and transfer an unfixed toner image to a recording material. An image forming method, comprising: fixing an image to an image to form an image. 10. The component (A) is a monomer selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid and dimethylmaleic acid, anhydrides thereof, and partially esterified products thereof. Or a copolymer having the monomer and a vinyl-based monomer.
The image forming method as described in the above. 11. The image forming method according to claim 9, wherein said component (B) has a copolymer having a diolefin monomer and a vinyl monomer. 12. The component (C) is represented by the following general formula: (Wherein R ₁ , R ₂ , R ₃ and R ₄ are each the same,
Which may be different, an alkyl group having 1 to 30 carbon atoms,
Aryl or aralkyl group which may have a substituent on the aromatic ring n represents 1 to 5, Ar represents an aryl group), and The image forming method according to claim 9, further comprising a quaternary ammonium salt represented by the formula: 13. The component (C) is represented by the following general formula: Wherein R ₅ is an alkyl group having 1 to 30 carbon atoms or an aralkyl group having 1 to 30 carbon atoms. n represents 1 to 5, and Ar represents an aryl group. ), And R ₆ represents an alkyl group having 1 to 10 carbon atoms, and the number of the substituent R ₆ is one or more. The image forming method according to claim 9, further comprising a quaternary ammonium salt represented by the formula: 14. The component (D) has the following general formula: (Wherein, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ may be the same or different from each other, and may be a hydrogen, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. And R ₇ , R ₈ and R ₉ each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group which may be the same or different from each other, and A ⁻ represents an anion.) The image forming method according to claim 9, further comprising a dye. 15. The anion is a nitrate ion, borate ion, phosphate ion, hydroxide ion, organic sulfate ion, organic sulfonate ion, organic phosphate ion, carboxylate ion, organic borate ion or tetrafluoro ion. The image forming method according to claim 14, wherein the image is a borate. 16. The composition according to claim 9, wherein the component (D) comprises a compound selected from the group consisting of a nigrosine dye, a nigrosine dye treated with a fatty acid, and a nigrosine dye treated with a resin acid. Image forming method. 17. An electrostatic image carrier for carrying an electrostatic image, charging means for charging the electrostatic image carrier, and developing the electrostatic image carried on the electrostatic image carrier. Developing means for transferring the developed image developed by the developing means from the electrostatic image carrier to a recording material, and applying heat and pressure to the unfixed toner image transferred to the recording material. In the image forming apparatus having a fixing unit for fixing to the recording material, the developing unit includes a positively chargeable magnetic toner having at least a binder resin, a magnetic material, and a positively chargeable magnetic toner particle having a charge control agent; A toner carrier for charging the positively chargeable magnetic toner to a positive charge by friction with the positively chargeable magnetic toner; and the binder resin comprises (A) a carboxyl group and an acid group as polar functional groups. And / or partial esters thereof And (B) a copolymer polymerized with at least a diolefin-based monomer and a vinyl-based monomer. (C) a quaternary ammonium salt and (D)
It has a nigrosine-based dye or a triphenylmethane-based dye, and the weight ratio of the components is as follows: component (A) and component (B)
(A): (B): (C):
(D) = 80-30: 70-20: 2.0-0.5:
An image forming apparatus having a ratio of 2.0 to 0.1. 18. The component (A) is a monomer selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid and dimethylmaleic acid, their anhydrides and their partially esterified products. A homopolymer having the formula (1) or a copolymer having the monomer and a vinyl monomer.
8. The image forming apparatus according to 7. 19. The image forming apparatus according to claim 17, wherein the component (B) has a copolymer having a diolefin monomer and a vinyl monomer. 20. The component (C) has the following general formula: (Wherein R ₁ , R ₂ , R ₃ and R ₄ are each the same,
Which may be different, an alkyl group having 1 to 30 carbon atoms,
Aryl group or aralkyl group which may have a substituent on the aromatic ring n represents 1 to 5, and Ar represents an aryl group). The image forming apparatus according to claim 17, further comprising a quaternary ammonium salt represented by the following formula: 21. The component (C) is represented by the following general formula: Wherein R ₅ is an alkyl group having 1 to 30 carbon atoms or an aralkyl group having 1 to 30 carbon atoms. n represents 1 to 5, and Ar represents an aryl group. ), R ₆ represents an alkyl group having 1 to 10 carbon atoms, and the number of the substituents R ₆ is one or more. The image forming apparatus according to claim 17, further comprising a quaternary ammonium salt represented by the following formula: 22. The component (D) has the following general formula: (Wherein, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ may be the same or different from each other, and may be a hydrogen, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. And R ₇ , R ₈ and R ₉ each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group which may be the same or different from each other, and A ⁻ represents an anion.) The image forming apparatus according to claim 17, further comprising a dye. 23. The anion is a nitrate ion, borate ion, phosphate ion, hydroxyl ion, organic sulfate ion, organic sulfonate ion, organic phosphate ion, carboxylate ion, organic borate ion or tetrafluoro ion. 23. The image forming apparatus according to claim 22, wherein the image forming apparatus is a borate. 24. The method according to claim 17, wherein the component (D) has a compound selected from the group consisting of a nigrosine dye, a nigrosine dye treated with a fatty acid, and a nigrosine dye treated with a resin acid. Image forming device. 25. An electrostatic image carrier for carrying an electrostatic image, wherein at least one of a charging means for charging the electrostatic image carrier is supported by the electrostatic image carrier. A unit formed integrally with the developing means for developing the image, the unit comprising a transferring means for transferring the developed image developed by the developing means from the electrostatic image carrier to a recording material; And a transfer unit for transferring to the recording material, and a fixing unit for fixing the unfixed toner image transferred to the recording material to the recording material by heat and pressure, and is detachably attached to an apparatus main body. In the apparatus unit, the developing unit may include a positively chargeable magnetic toner having at least a binder resin, a magnetic substance, and a positively chargeable magnetic toner particle having a charge control agent, and the positively chargeable magnetic toner by friction with the positively chargeable magnetic toner. The binder resin has (A) a carboxyl group, an acid group, and / or an acid group formed by partial esterification thereof as a polar functional group. And a vinyl polymer having an acid value of 5 to 30 and (B) at least a copolymer polymerized with a diolefin monomer and a vinyl monomer, wherein the charge control agent is (C) quaternary Ammonium salt and (D)
It has a nigrosine-based dye or a triphenylmethane-based dye, and the weight ratio of the components is as follows: component (A) and component (B)
(A): (B): (C):
(D) = 80-30: 70-20: 2.0-0.5:
An apparatus unit having a ratio of 2.0 to 0.1. 26. The component (A) is a monomer selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid and dimethylmaleic acid, their anhydrides and their partially esterified products. 3. A homopolymer having the formula (1) or a copolymer having the monomer and a vinyl monomer.
6. The device unit according to 5. 27. The apparatus unit according to claim 25, wherein said component (B) has a copolymer having a diolefin monomer and a vinyl monomer. 28. The component (C) has the following general formula: (Wherein R ₁ , R ₂ , R ₃ and R ₄ are each the same,
Which may be different, an alkyl group having 1 to 30 carbon atoms,
An aryl or aralkyl group which may have a substituent on the aromatic ring n represents 1 to 5, and Ar represents an aryl group). 26. The apparatus unit according to claim 25, further comprising a quaternary ammonium salt represented by the following formula. 29. The component (C) is represented by the following general formula: (Wherein, R ₅ is an alkyl group having 1 to 30 carbon atoms or an aralkyl group having 1 to 30 carbon atoms.) n represents 1 to 5, and Ar represents an aryl group. And R ₆ represents an alkyl group having 1 to 10 carbon atoms, and the substituent R ₆ is one or more. 26. The apparatus unit according to claim 25, further comprising a quaternary ammonium salt represented by the following formula. 30. The component (D) has the following general formula: (Wherein, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ may be the same or different from each other, and may be a hydrogen, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. And R ₇ , R ₈ and R ₉ each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group which may be the same or different from each other, and A ⁻ represents an anion.) 26. The device unit of claim 25, comprising a dye. 31. The anion is a nitrate ion, borate ion, phosphate ion, hydroxyl ion, organic sulfate ion, organic sulfonate ion, organic phosphate ion, carboxylate ion, organic borate ion or tetrafluoro ion. 31. The device unit according to claim 30, wherein the device unit is a borate. 32. The component according to claim 25, wherein the component (D) has a compound selected from the group consisting of a nigrosine dye, a nigrosine dye treated with a fatty acid, and a nigrosine dye treated with a resin acid. Equipment unit. 33. An electrostatic image carrier for carrying an electrostatic image, a charging means for charging the electrostatic image carrier, and developing the electrostatic image carried on the electrostatic image carrier. Developing means for transferring the developed image developed by the developing means from the electrostatic image carrier to a recording material, and applying heat and pressure to the unfixed toner image transferred to the recording material. An electrophotographic apparatus having a fixing unit for fixing the recording material to the recording material, and a facsimile apparatus having a receiving unit for receiving image information from a remote terminal, wherein the developing unit comprises at least a binder resin, a magnetic material, and charge control. A positively-chargeable magnetic toner having positively-chargeable magnetic toner particles having a toner agent, and a toner carrier for charging the positively-chargeable magnetic toner to a positive charge by friction with the positively-chargeable magnetic toner; The binder resin is (A) a vinyl polymer having a carboxyl group, an acid group and / or an acid group formed by partial esterification thereof as a polar functional group, and an acid value of 5 to 30; and (B) at least a diolefin monomer And a copolymer polymerized with a vinyl monomer, wherein the charge control agent is (C) a quaternary ammonium salt and (D)
It has a nigrosine-based dye or a triphenylmethane-based dye, and the weight ratio of the components is as follows: component (A) and component (B)
(A): (B): (C):
(D) = 80-30: 70-20: 2.0-0.5:
A facsimile machine having a ratio of 2.0 to 0.1. 34. The component (A) is a monomer selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid and dimethylmaleic acid, anhydrides thereof, and partially esterified products thereof. 4. A homopolymer having the formula (1) or a copolymer having the monomer and a vinyl monomer.
3. The facsimile apparatus according to 3. 35. The facsimile apparatus according to claim 33, wherein said component (B) has a copolymer having a diolefin monomer and a vinyl monomer. 36. The component (C) has the following general formula: (Wherein R ₁ , R ₂ , R ₃ and R ₄ are each the same,
Which may be different, an alkyl group having 1 to 30 carbon atoms,
Aryl group or aralkyl group which may have a substituent on the aromatic ring n represents 1 to 5, and Ar represents an aryl group). 34. The facsimile apparatus according to claim 33, further comprising a quaternary ammonium salt represented by: 37. The component (C) is represented by the following general formula: Wherein R ₅ is an alkyl group having 1 to 30 carbon atoms or an aralkyl group having 1 to 30 carbon atoms. n represents 1 to 5, and Ar represents an aryl group. ), And R ₆ represents an alkyl group having 1 to 10 carbon atoms, and the number of the substituent R ₆ is one or more. 34. The facsimile apparatus according to claim 33, further comprising a quaternary ammonium salt represented by: 38. The component (D) has the following general formula: (Wherein, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ may be the same or different from each other, and may be a hydrogen, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. And R ₇ , R ₈ and R ₉ each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group which may be the same or different from each other, and A ⁻ represents an anion.) The facsimile apparatus according to claim 33, further comprising a dye. 39. The anion is a nitrate ion, borate ion, phosphate ion, hydroxyl ion, organic sulfate ion, organic sulfonate ion, organic phosphate ion, carboxylate ion, organic borate ion or tetrafluoro ion. The facsimile apparatus according to claim 38, wherein the facsimile apparatus is a borate. 40. The component according to claim 33, wherein the component (D) comprises a compound selected from the group consisting of a nigrosine dye, a nigrosine dye treated with a fatty acid, and a nigrosine dye treated with a resin acid. Facsimile machine.