JPH08202075A - Electrostatic charge image developing toner composition and image forming method - Google Patents

Abstract

PURPOSE: To provide an electrostatic charge image developing toner which does not damage a photoreceptor or a dielectric surface in an electrophotographic process, nor causes filming on the photoreceptor surface or a cleaning member, and has stable characteristics for repeated use, and to provide an image forming method by which the transfer efficiency is improved and images of high reliability can be formed for a long time without any trouble in the image quality even when a transfer roller with bias applied is used to transfer images. CONSTITUTION: This electrostatic charge image developing toner is prepared by adding resin fine particles treated with oil to toner particles containing a binder resin and coloring agent. The image forming method includes a process to form a latent image on a latent image holding body having the outermost layer comprising an org. material, a process to develop the latent image, a process to transfer the toner image, and a process to remove the toner remaining on the latent image holding body. In the transferring process, a transfer roller with bias voltage applied is used to press and transfer an image. The electrostatic charge image developing toner is used as the developer of this method. In the transferring process, an image is transferred under pressure by the bias roller on the back surface of the transfer body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge image developing toner used for developing an electrostatic latent image in an electrostatic recording method or an electrophotographic method, and an image forming method using the toner.

[0002]

2. Description of the Related Art In electrophotography, an electrostatic latent image formed on a photoconductor or the like is developed with a developer, the toner image on the photoconductor is transferred to a transfer medium such as paper or sheet, and then the image is heated. The toner is fixed by using pressure, solvent and the like to obtain a permanent image, and the toner remaining on the photoconductor at that time is removed from the photoconductor by a cleaning device. Therefore, in order for the electrophotographic method to be completed as a system having stable repeating characteristics, it is necessary that each process for forming an image be fully functional. In each of these processes, when the photoconductor and the cleaning member are in direct contact with each other in the cleaning process, damage to the photoconductor surface such as scratches and abrasion, filming, etc., and image defects due to poor cleaning may occur. There is. Therefore, a high cleaning property is required in the cleaning process. Also,
In recent years, the use of recycled paper is increasing to save resources. Generally, recycled paper generates a large amount of paper dust, so paper dust and the like enter between the photoconductor and the cleaning member, causing black stripes and the like. There is a problem that induces poor cleaning,
Higher cleaning performance is required.

Conventionally, it has been proposed to externally add various additives to toner particles in order to improve fluidity, durability, or cleaning property. For example, it has been proposed to obtain a toner by adding fine powder of an inorganic compound such as silica, alumina or titania (Japanese Patent Laid-Open No. 59-226).
355, JP 61-23160, JP 63-118757, JP 2-1870, JP 2-90175, etc.). However,
When silica, alumina, fine powder of an inorganic compound such as titania is added, the fluidity of the toner is remarkably improved, but since the hardness of these fine powders is high, a dent or a scratch is easily formed on the surface of the photoreceptor, Further, there is a problem that the toner is likely to adhere to the damaged portion.

In order to solve these problems, a method of externally adding a fatty acid metal salt, polyolefin or the like as an additive to the toner particles has been studied (Japanese Patent Laid-Open No. 54-16219).
JP, JP-A-60-198556, JP, JP-A-61
-231562, JP-A-61-231563, etc.). However, all of the fatty acid metal salts and polyolefins disclosed in the above publications, even if effective at the beginning of addition, have the property that the additives themselves are easily filmed on the photoconductor, and therefore, they are repeatedly used. During cleaning, due to pressure between the photoconductor and the cleaning member, non-uniform filming occurs on the photoconductor surface,
There is a problem in that the density of the photosensitive member is lowered, the fog is generated, and the image becomes white and blurred. On the other hand, it has been studied to coat the toner surface with resin fine powder of a homopolymer or a copolymer of acrylic acid ester monomer, methacrylic acid ester monomer, styrene-based monomer and the like (Japanese Patent Publication No. 2-3188). Although addition of these resin fine powders to the toner is one effective means for improving the cleaning property, recently, the copying speed of a copying machine or a printer tends to be higher. Along with this, stress (load, speed) applied to the photoconductor at the time of cleaning also increases, so that the resin fine powder is deformed on the surface of the photoconductor, causing a problem such as filming.

Further, in order to reduce the stress at the time of cleaning, a method of externally adding silicon resin fine particles to toner particles has been studied (Japanese Patent Laid-Open No. 64-49052).
Japanese Patent Application Laid-Open No. 1-106073, Japanese Patent Application Laid-Open No. 1-260
93354, Japanese Patent Laid-Open No. 2-55367, etc.).
Addition of silicone resin fine particles to the toner is an effective means for improving the cleaning property, and cleaning failure or
This has the effect of reducing toner adhesion to the photoreceptor. However, the silicon resin fine particles have a smaller effect than the inorganic compound fine powder described above, but also have an effect as an abrasive. Therefore, if the surface of the photoconductor is repeatedly cleaned at high speed, the photoconductor is worn or the photoconductor is abraded. There is a problem of being hurt. On the other hand, in recent years, in consideration of the office environment, a charging method using a conventional corotron, a charging roller that hardly generates ozone, which is an alternative to a transfer method, and a method using a transfer roller have been devised and put into practical use. However, when the transfer is performed by the transfer roller, a defect such that a part of the image portion is not transferred and is missing easily occurs, and particularly when the transfer body is an OHP sheet, this tendency becomes remarkable. To solve this problem, in the toner particles,
A method of adding an inorganic oxide treated with silicone oil has been proposed. However, in order to solve the above problems, it is necessary to add a large amount to the toner. Therefore, the external additive is easily detached from the toner, and the hardness of these fine powders is high. There is a problem in that the film quality appears, the surface of the photoconductor is scratched, the outermost surface layer is abraded, and the like, which results in an image quality defect.

[0006]

SUMMARY OF THE INVENTION The present invention has been made for the purpose of solving the above-mentioned problems in the prior art. An object of the present invention is to develop an electrostatic charge image having stable repetitive characteristics without damaging the surface of the photoconductor or the dielectric in the cleaning step, causing no filming phenomenon on the surface of the photoconductor or the cleaning member. To provide toner for use. Another object of the present invention is to provide an image forming method capable of forming a highly reliable image for a long period of time without causing image troubles such as whitening, fog, density reduction, image blurring, and black streaks.
Another object of the present invention is to provide an electrostatic charge image developing toner which improves transfer efficiency even when transferred by a transfer roller to which a bias is applied and which does not cause image defects regardless of the type of transfer body. It is in.

[0007]

The toner for developing an electrostatic charge image of the present invention comprises toner particles containing a binder resin and a colorant,
It is characterized in that resin fine particles treated with oil are added. The image forming method of the present invention comprises a step of forming a latent image on a latent image carrier whose outermost surface layer is made of an organic material, a step of developing the latent image with a developer, and a step of transferring the formed toner image. In the image forming method, which comprises a step of transferring the toner onto the body and a step of removing the residual toner on the latent image holding body, and the transferring step is a pressure-contact transfer by a transfer roller to which a bias is applied, the electrostatic image development described above as a developer. It is characterized in that the toner is used for transfer, and the transfer is performed by pressure contact transfer from the back surface of the transfer body using a bias roller. In the present invention, “resin fine particles treated with oil” means resin fine particles impregnated with oil and / or resin fine particles surface-treated with oil by treating the resin fine particles with oil. .

The present invention will be described in detail below. As the toner particles used in the present invention, conventionally known toner particles composed of a binder resin and a colorant are used. Typical examples of the binder resin used include styrenes such as styrene and chlorostyrene, monoolefins such as ethylene, propylene, butylene and isoprene, vinyl acetate, vinyl propionate, vinyl benzoate and vinyl acetate. Α-Methylene aliphatic monoesters such as vinyl ester, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate. Examples thereof include carboxylic acid esters, vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl butyl ether, and homopolymers or copolymers of vinyl ketones such as vinyl methyl ketone and vinyl hexyl ketone. Particularly typical binder resins include polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, polyethylene, polypropylene and the like. further,
Other examples include polyester, polyurethane, epoxy resin, and silicone resin. Among these, styrene resin and polyester resin are particularly preferably used.

Typical colorants used include carbon black, aniline blue, calcoil blue, chrome yellow, DuPont oil red, quinoline yellow, phthalocyanine blue, rose bengal, C.I. I. Pigment Red 48: 1, C.I. I. Pigment Red 122, C.I. I. Pigment Red 57:
1, C.I. I. Pigment Yellow 97, C.I. I. Pigment Yellow 12, C.I. I. Pigment Blue 15:
1, C.I. I. Pigment Blue 15: 3 and the like.

A charge control agent may be added to the toner particles if necessary. As the charge control agent, known compounds can be used, but it is preferable to use an azo metal complex, a salicylic acid metal complex, nigrosine or a quaternary ammonium salt. Further, other known components such as low molecular weight polypropylene, low molecular weight polyethylene, offset preventing agents such as wax, polyvinylidene fluoride fine particles, polystyrene fine particles, polymethylmethacrylate fine particles and the like can be added. Further, the toner particles in the present invention may be a magnetic toner containing a magnetic material or a capsule toner. The average particle size of the toner particles is 3 μm to 20 μm.
The range of m is preferable. Further, in order to improve the fluidity of the toner, silica (SiO ₂ ), titanium oxide (T
Inorganic oxides such as io ₂ ) and alumina (Al ₂ O ₃ ) or their surfaces are used in combination with silane coupling agents, titanium coupling agents, other resins, or fine particles treated with the above charge control agents. It can be added.

The resin fine particles used in the present invention include:
Known various synthetic resins, specifically, an acrylate resin and a copolymer thereof produced by the following method,
Examples thereof include fine particles of a methyl methacrylate resin, an ethyl methacrylate resin, polystyrene, a methyl methacrylate-styrene copolymer, a butadiene resin and a copolymer thereof, and a silicon rubber fine particle.
These resin fine particles can be obtained by a known method, but in particular, can be produced by a suspension polymerization reaction using a dispersion aid or an emulsion polymerization reaction using an emulsifier or unused (soap-free). As its average particle size,
The range of 0.05 to 5 μm, preferably the range of 0.1 to 2 μm is used. The resin fine particles treated with oil used in the present invention can be obtained by adding oil to the polymerization reaction system at the same time as a monomer for polymerization and polymerizing, and the untreated resin fine particles are converted into alcohol. It can also be obtained by a method of dispersing and mixing in a dissolved oil, then distilling off the alcohol of the solvent using an evaporator and drying.

The substantially spherical silicon rubber fine particles externally added to the toner particles of the present invention have the general formula:-(R ₂ SiO) _n- (wherein R is an alkyl group such as a methyl group, an ethyl group or a propyl group, It represents an organic group selected from aryl groups such as phenyl group and tolyl group, and halogenated alkyl groups such as chloromethyl group.). The production of these spherical silicon rubber fine particles is

Embedded image The ones given by The molecular structure of the silicone rubber may be linear or branched, and may be a mixture thereof.

The substantially spherical silicone rubber fine particles used in the present invention must have a rubber hardness of 10 to 70, and preferably in the range of 20 to 50.
When the rubber hardness is lower than 10, the silicone rubber fine particles are likely to aggregate with each other, resulting in insufficient cleaning property. On the other hand, when it is larger than 70, the surface of the photoconductor is easily scratched. In the present invention, the rubber hardness means a rubber hardness measured by an A-type hardness tester according to JIS K6301.

Examples of the type of oil used for treating the resin fine particles include dimethyl silicone oil, methylphenyl silicone oil, amino group-containing silicone oil, fluorine-modified silicone oil, epoxy-modified silicone oil, and mercapto-modified silicone oil. . The amount of oil used for the treatment is in the range of 5 to 40% by weight, preferably 10 to 30 with respect to the resin fine particles.
It is in the range of% by weight. If this treatment is performed at less than 5% by weight, the sufficient effect of the treatment cannot be obtained,
When the amount is more than the amount by weight, the rubber fine particles are likely to be aggregated to reduce the fluidity of the toner. The oil-treated resin fine particles are preferably added in the range of 0.1 to 3 parts by weight with respect to 100 parts by weight of the toner particles.

Next, the image forming method of the present invention will be described. An electrophotographic photosensitive member and a dielectric are used as the latent image holding member whose outermost surface layer used in the step of forming a latent image is made of an organic material. As the electrophotographic photosensitive member, the outermost surface layer is made of an organic photosensitive layer in which a photoconductive material is dispersed in a binder resin, a protective layer made of a synthetic resin, etc.
Known ones are used. Specific examples include a charge transport layer in which a charge transport agent is dispersed in a polycarbonate resin. As the dielectric whose outermost layer is made of an organic material, one having a dielectric layer made of a synthetic resin such as polyester or polycarbonate resin on a substrate is used. The latent image can be formed by a conventional method. For example, in the case of an electrophotographic photoreceptor, it can be uniformly charged by a corona charger or a bias roller and imagewise exposed. The latent image thus formed is developed using the above-mentioned toner for developing an electrostatic charge image. The toner for developing an electrostatic charge image may be used as either a one-component developer or a two-component developer. Good. The toner image formed by the development is transferred onto a transfer body such as transfer paper by a corotron or a bias application transfer roller, and is fixed by heating to form an image. On the other hand, the toner remaining on the latent image holding member is cleaned by the cleaning member, and is supplied to the next copying operation. In the present invention, a bias roller that performs pressure contact transfer is particularly preferably used. In the case of this pressure transfer, it is possible to transfer at a linear pressure of at least 5 g / cm as a pressure contact force, and even in that case, a good image can be obtained.

[0016]

The resin fine particles treated with oil in the present invention have a hardness smaller than that of the inorganic oxide and an average particle diameter of 0.05 μm or more. Contact with other inorganic oxides added on the surface can be suppressed, and because the resin fine particles are treated with oil, the coefficient of friction between the toner and the photoreceptor is significantly reduced, and therefore the transfer It is considered that the transfer efficiency at the time is improved, and image defects do not occur even when transferring with a bias roller. When the resin fine particles are silicon rubber fine particles, since they are rubber-like elastic fine particles, the details thereof are unclear by adding them to the toner particles. It is considered that the rubber fine particles are elastically deformed, and the restoring force enhances the cleaning effect by stirring the toner in the vicinity of the cleaning member. Further, it is considered that the low surface energy of the silicon rubber fine particles suppresses the transfer of the silicon rubber fine particles to the photoconductor, and suppresses the filming on the photoconductor. Also, since it is a rubber-like elastic fine particle,
It is considered that it acts softly on the photoconductor and does not damage the photoconductor. Further, the effect is further enhanced by using the silicone rubber fine particles treated with oil. The cause is not clear, but it is considered that the oil treatment reduces the adhesion between the toner and the surface of the photoconductor. In addition, since it contains oil and can be elastically deformed, the contact area increases due to the pressure contact of the transfer roller,
As a result, the transfer efficiency is further improved, and it is considered that the image loss can be prevented even when the image is transferred by the transfer roller.

[0017]

The present invention will be described in detail below with reference to examples, but the scope of the present invention is not limited to the following examples. In the following, “part” means “part by weight”. Example 1 (Production of magnetic toner particles) 100 parts by weight of styrene-butyl acrylate copolymer (80/20) (Mw = 2.0 × 10 ⁵ , Mn = 4,000, Tg = 62 ° C.) Magnetic substance (EPT1000) : Toda Kogyo Co., Ltd.) 45 parts by weight Low molecular weight polypropylene (Viscole 660P: Sanyo Kasei Co., Ltd.) 3 parts by weight Charge control agent (Spiron Black TRH: Hodogaya Chemical Co., Ltd.) 2 parts by weight The above components are biaxially extruded. The mixture was melt-kneaded with a machine, cooled, coarsely pulverized, finely pulverized with a jet mill, and further classified with a classifier to obtain magnetic toner particles having an average particle diameter (volume) of 10 μm. (Production of silicone oil treated resin fine particles) 20 parts of dimethyl silicone oil is dissolved in 500 parts of ethanol,
Polymethylmethacrylate resin with an average particle size of 0.5 μm 1
After stirring and mixing with 00 parts, the solvent ethanol was distilled off using an evaporator and dried to obtain an oil-treated polymethylmethacrylate resin. Next, this treated product was crushed using a mortar and sieved with a 105 μm mesh sieve to obtain a polymethylmethacrylate resin treated with dimethyl silicone oil. (Mixing of Magnetic Toner Particles and External Additive) 100 parts of the magnetic toner particles obtained above, 0.5 part of hydrophobic silica (R-972: manufactured by Nippon Aerosil Co., Ltd.), and poly treated with the above dimethyl silicone oil. 0.5 parts of methyl methacrylate resin was mixed with a Henschel mixer to obtain a magnetic toner composition in which an external additive was attached to the toner surface.

Example 2 In the same manner as in Example 1, except that 20 parts of dimethyl silicone oil was replaced with 10 parts, 0.5 parts of hydrophobic silica (R-972) and dimethyl silicone oil were treated in exactly the same manner. A magnetic toner composition was obtained in which 0.5 part of polymethylmethacrylate resin was attached to the toner surface.

Example 3 In Example 1, the hydrophobic silica (R-972) 0.5 was used.
Polymethylmethacrylate resin 0.5 treated with 1.0 part of hydrophobic silica (R-972) and dimethyl silicone oil in exactly the same manner except that the parts were replaced with 1.0 part.
A magnetic toner composition having a part of the toner adhered to the toner surface was obtained.

Example 4 In Example 1, polymethylmethacrylate resin having an average particle size of 0.5 μm was replaced with polymethylmethacrylate-styrene copolymer resin (80/20) having an average particle size of 0.8 μm.
Except that the hydrophobic silica (R-
972) 0.5 parts and 0.5 parts of polymethylmethacrylate-styrene copolymer resin (80/20) treated with dimethyl silicone oil were adhered to the toner surface to obtain a magnetic toner composition.

Example 5 (Production of carrier particles for two-component development) Central particle size 60 μm
100 parts of ferrite of polymethylmethacrylate (B
(R-87: Mitsubishi Rayon Co., Ltd.) 1.5 parts of toluene solution was added to 80 parts of toluene solution, mixed and dissolved at room temperature and normal pressure for 20 minutes, and heated under reduced pressure with stirring to distill off toluene. Then, the particles were sieved with a 105 μm sieve to obtain carrier particles. (Production of Non-Magnetic Toner Particles for Two-Component Development) Styrene-butyl acrylate copolymer (80/20) 100 parts by weight (Mw = 2.0 × 10 ⁵ , Mn = 4,000, Tg = 62 ° C.) Carbon black (Legal 330: manufactured by Cabot Co., Ltd.) 10 parts by weight Low molecular weight polypropylene (Viscor 660P: manufactured by Sanyo Kasei Co., Ltd.) 6 parts by weight Charge control agent (Spiron Black TRH: manufactured by Hodogaya Chemical Co., Ltd.) 2 parts by weight The above components are Banbury mixers. Was melt-kneaded with, cooled, coarsely pulverized, finely pulverized with a jet mill, and further classified with a classifier to obtain non-magnetic toner particles having an average particle size (volume) of 10 μm. (Preparation of Two-Component Developer) Nonmagnetic Toner Particle 100
Parts, 0.5 parts of hydrophobic silica (R-972), and 0.5 parts of polymethylmethacrylate resin treated with dimethyl silicone oil of Example 1 are mixed with a Henschel mixer to allow external additives to adhere to the toner surface. A magnetic toner composition was obtained. 5 parts of the obtained magnetic toner composition and 95 parts of the above carrier particles were mixed with a V-blender to prepare a two-component developer.

Comparative Example 1 In Example 1, except that the polymethylmethacrylate resin treated with dimethyl silicone oil was not used.
A magnetic toner composition having 0.5 parts of hydrophobic silica (R-972) attached to the toner surface was obtained in exactly the same manner. Comparative Example 2 In Comparative Example 1, the hydrophobic silica (R-972) 0.5
A magnetic toner composition having 1.0 part of hydrophobic silica (R-972) attached to the toner surface was obtained in exactly the same manner except that the parts were replaced by 1.0 part. Comparative Example 3 In Example 1, instead of 0.5 part of polymethylmethacrylate resin treated with dimethyl silicone oil,
A magnetic toner composition was obtained in exactly the same manner except that 0.5 part of untreated polymethylmethacrylate resin was used.

Comparative Example 4 (Production of Inorganic Oxide Treated with Silicone Oil) 20 parts of dimethyl silicone oil was dissolved in 500 parts of ethanol, mixed with 100 parts of hydrophobic silica (R-972) with stirring, and then a solvent was added using an evaporator. The ethanol was distilled off and dried to obtain oil-treated silica fine powder.
Next, this treated product was crushed using a mortar and sieved with a sieve having a mesh of 105 μm to obtain silica fine powder treated with dimethyl silicone oil. Next, 100 parts of the magnetic toner particles of Example 1 and 1.0 part of the silica fine powder treated with the above dimethyl silicone oil were mixed with a Henschel mixer to obtain a magnetic toner composition in which an external additive was attached to the toner surface. It was Comparative Example 5 In Example 5, instead of 0.5 part of polymethylmethacrylate resin treated with dimethyl silicone oil,
A two-component developer was prepared in exactly the same manner except that 0.5 part of untreated polymethylmethacrylate resin was used.

(Evaluation of Developer) The developers obtained in Examples 1 to 5 and Comparative Examples 1 to 5 were evaluated. For the magnetic toner, the Vivace 200 modified so that transfer and reversal development with a bias roller can be performed.
Using a modified machine (manufactured by Fuji Xerox Co., Ltd.), and for the two-component developer, similarly modified Vivace 500
Each was evaluated using a modified machine (manufactured by Fuji Xerox Co., Ltd.). The continuous copying test is 5 for magnetic toner.
Up to 10,000 sheets, and for two-component developer, 15
It was carried out up to 10,000 sheets. The test environment is 20 ℃, 50%
Performed at RH. The image density was measured with a Macbeth densitometer and the density was 1.3 when the fog was not present on the copied image.
As described above, Δ indicates 1.1 to less than 1.3. The transfer efficiency was evaluated according to the following criteria by transferring the image on the photoconductor to a tape using a solid patch and measuring the weight before and after transferring it to plain paper. Transfer efficiency: ○: 95% or more, △: 90 to less than 95%, ×
Is less than 90%. The image loss during transfer on the OHP sheet was evaluated by observing the character portion and grading as follows. Image omission on OHP sheet: G1 has no image omission, G2 has only a slight image omission (to the extent that it can be seen when enlarged), G3 has some image omission, and G4 has image omission.

Table 1 shows the evaluation results of Examples 1-5 and Comparative Examples 1-5.

[Table 1]

An example of using silicon rubber fine particles as the resin fine particles of the present invention will be described below. Production Example 1 (Production of Silicon Rubber Fine Particles) 250 g of methyl vinyl siloxane and 30 g of methyl hydrogen polysiloxane
Were mixed in a flask to prepare an organosiloxane composition. Next, polyoxyethylene octyl ether 1
0 g and 300 g of pure water were added, an emulsion was prepared using a homomixer, and while stirring this emulsion, 0.5 g of a toluene solution of a chloroplatinic acid-olefin complex (platinum content 0.02) and polyoxyethylene. A mixture of 0.5 g of octyl ether was added and reacted at 30 ° C. for 7 hours. Next, this emulsion is heated to 80 ° C., 30 g of potassium sulfate is added to break the emulsion, pressure filtration is performed with a 300 mesh filter, 1000 g of pure water is added to this cake-like substance, and stirring and washing are performed. It was Then, the mixture was pressure filtered with a 300-mesh filter, and the obtained separated product was dried with a hot air drier to obtain spherical silicon rubber fine particles having an average particle diameter of 1.8 μm. The rubber hardness was 50.

Production Example 2 (Treatment of Silicon Rubber Fine Particles) 20 parts of dimethyl silicone oil was dissolved in 500 parts of ethanol, and the mixture was stirred and mixed with 100 parts of the above silicone rubber fine particles, and then the solvent ethanol was distilled off using an evaporator. Then, the dried and surface-treated silicon rubber fine particles were obtained. Next, this treated product was disintegrated using a mortar and sieved with a 105 μm mesh sieve to obtain silicon rubber fine particles surface-treated with dimethyl silicone oil. Production Example 3 Silicon rubber fine particles surface-treated with dimethyl silicone oil were obtained in exactly the same manner as in Production Example 2 except that 20 parts of dimethyl silicone oil was replaced with 10 parts. Production Example 4 Silicon rubber fine particles surface-treated with methylphenyl silicone oil were obtained in exactly the same manner as in Production Example 2 except that 20 parts of dimethyl silicone oil was replaced with 20 parts of methylphenyl silicone oil.

Production Example 5 (Production of Magnetic Toner Particles) 100 parts by weight of styrene-butyl acrylate copolymer (80/20) (Mw = 2.0 × 10 ⁵ , Mn = 4,000, Tg = 62 ° C.) Magnetic Body (EPT1000: manufactured by Toda Kogyo Co., Ltd.) 45 parts by weight Low molecular weight polypropylene (Viscole 660P: manufactured by Sanyo Kasei Co., Ltd.) 3 parts by weight Charge control agent (Spiron Black TRH: manufactured by Hodogaya Chemical Co., Ltd.) 2 parts by weight After melt-kneading with a twin-screw extruder, cooling, coarse pulverization, fine pulverization with a jet mill, and classification with a classifier to obtain magnetic toner particles having an average particle size (volume) of 10 μm.

Production Example 6 (Production of non-magnetic toner particles for two-component development) 100 parts by weight of styrene-butyl acrylate copolymer (80/20) (Mw = 2.0 × 10 ⁵ , Mn = 4,000, Tg) = 62 ° C) Carbon black (Regal 330: manufactured by Cabot) 10 parts by weight Low molecular weight polypropylene (Viscor 660P: manufactured by Sanyo Kasei Co., Ltd.) 6 parts by weight Charge control agent (Spiron Black TRH: manufactured by Hodogaya Chemical Co., Ltd.) 2 parts by weight The above components were melt-kneaded by a Banbury mixer, cooled, coarsely pulverized, finely pulverized by a jet mill, and further classified by a classifier to obtain non-magnetic toner particles having an average particle size (volume) of 10 μm.

Production Example 7 (Production of Carrier Particles for Two-Component Development) Central Particle Diameter 60 μm
100 parts of ferrite was put into 80 parts of a toluene solution in which 1.5 parts of polymethylmethacrylate (manufactured by Mitsubishi Rayon: BR-87) was dissolved, mixed at room temperature and atmospheric pressure for 20 minutes, and then heated under reduced pressure while stirring. And toluene was distilled off, followed by sieving with a 105 μm sieve to obtain carrier particles.

Production Example 8 (Mixing of External Additive to Magnetic Toner Particles) The magnetic toner particles obtained in Production Example 5 were mixed with hydrophobic silica (R-972: Nippon Aerosil Co., Ltd.) in Production Examples 1 to 4. The obtained silicone oil-treated or untreated silicon rubber fine particles were put into a Henschel mixer at a predetermined ratio and mixed to prepare a magnetic toner composition having an external additive attached.

Production Example 9 (Preparation of Two-Component Developer) Non-magnetic toner particles obtained in Production Example 6, hydrophobic silica (R-972: manufactured by Nippon Aerosil Co., Ltd.) and Production Examples 1 to 4 were obtained. Silicone oil-treated or untreated silicone rubber fine particles were introduced into a Henschel mixer at a predetermined ratio and mixed to prepare a non-magnetic toner composition to which an external additive was attached. 5 parts of the above toner composition and 95 parts of the carrier particles obtained in Production Example 6 were mixed in a V blender to prepare a two-component developer. The above-mentioned magnetic toner can be transferred by a modified machine which is a modified version of Vivece 200 for transfer and reversal development by bias roller, and the two-component developer can be transferred by corotron transfer or transfer by bias roller, and further reversal development is possible. The Vivace 500 (manufactured by Fuji Xerox Co., Ltd.) was modified as described above, and a continuous copying test was conducted.

Production Example 10 (Production of Silicone Oil Treated Inorganic Oxide Fine Powder) 20 parts of dimethyl silicone oil was dissolved in 500 parts of ethanol and mixed with 100 parts of hydrophobic silica (R-972: Nippon Aerosil Co., Ltd.) with stirring. After that, ethanol as a solvent was distilled off by using an evaporator and dried to obtain surface-treated silica. Next, crush this product using a mortar and
After sieving with a sieve having a mesh of 05 μm, a silica fine powder surface-treated with dimethyl silicone oil was obtained.

Example 6 Silicon rubber fine particles treated with 100 parts of the magnetic toner particles obtained in Production Example 5, 0.5 parts of hydrophobic silica (R-972) and the dimethyl silicone oil obtained in Production Example 2 0.5 parts were mixed with a Henschel mixer to obtain a magnetic toner composition having an external additive adhered to the toner surface.

Example 7 Silicon rubber fine particles treated with 100 parts of the magnetic toner particles obtained in Production Example 5, 0.5 parts of hydrophobic silica (R-972) and dimethyl silicone oil obtained in Production Example 3 0.8 parts were mixed with a Henschel mixer to obtain a magnetic toner composition having an external additive adhered to the toner surface.

Example 8 Silicon rubber fine particles treated with 100 parts of the magnetic toner particles obtained in Production Example 5, 0.5 parts of hydrophobic silica (R-972) and the methylphenyl silicone oil obtained in Production Example 4 Mix 0.5 parts with a Henschel mixer,
A magnetic toner composition having an external additive attached to the toner surface was obtained.

Example 9 Silicon rubber fine particles treated with 100 parts of magnetic toner particles obtained in Production Example 5, 1.0 part of hydrophobic silica (R-972) and dimethyl silicone oil obtained in Production Example 2 0.5 parts were mixed with a Henschel mixer to obtain a magnetic toner composition having an external additive adhered to the toner surface.

Examples 10-11 Silicon treated with 100 parts of the non-magnetic toner particles obtained in Preparation Example 6, 0.5 parts of hydrophobic silica (R-972) and the dimethyl silicone oil obtained in Preparation Example 2. 0.5 parts of rubber fine particles were mixed by a Henschel mixer to obtain a non-magnetic toner composition in which an external additive was attached to the toner surface. 5 parts of the above toner composition and 95 parts of the carrier particles obtained in Production Example 7 were mixed with a V-blender to obtain a two-component developer.

Comparative Example 6 100 parts of the magnetic toner particles obtained in Production Example 5 and 0.5 part of hydrophobic silica (R-972) were mixed in a Henschel mixer, and an external additive was attached to the surface of the magnetic toner. A toner composition was obtained. Comparative Example 7 100 parts of the magnetic toner particles obtained in Production Example 5, 0.5 parts of hydrophobic silica (R-972) and 0.5 parts of the silicone rubber fine particles obtained in Production Example 1 were mixed with a Henschel mixer. A magnetic toner composition having an external additive attached to the toner surface was obtained. Comparative Example 8 A magnetic toner composition in which 100 parts of the magnetic toner particles obtained in Production Example 5 and 1.0 part of hydrophobic silica (R-972) were mixed with a Henschel mixer and an external additive was attached to the toner surface. Got Comparative Example 9 A magnetic toner composition in which 100 parts of the magnetic toner particles obtained in Production Example 5 and 1.5 parts of hydrophobic silica (R-972) were mixed with a Henschel mixer and an external additive was attached to the toner surface. Got

Comparative Example 10 100 parts of the non-magnetic toner particles obtained in Production Example 6 and 0.5 part of hydrophobic silica (R-972) were mixed with a Henschel mixer, and external additives were attached to the toner surface. A non-magnetic toner composition was obtained. 5 parts of this toner composition and Production Example 7
95 parts of the carrier particles obtained in (1) were mixed with a V-blender to obtain a two-component developer. Comparative Example 11 A non-magnetic toner obtained by mixing 100 parts of the non-magnetic toner particles obtained in Production Example 6 and 1.0 part of hydrophobic silica (R-972) with a Henschel mixer and attaching an external additive to the toner surface. A composition was obtained. 5 parts of this toner composition and Production Example 7
95 parts of the carrier particles obtained in (1) were mixed with a V-blender to obtain a two-component developer. Comparative Example 12 100 parts of the non-magnetic toner particles obtained in Production Example 6 and 0.5 part of hydrophobic silica (R-972) were mixed with a Henschel mixer, and an external additive was attached to the toner surface. A composition was obtained. 5 parts of this toner composition and Production Example 7
95 parts of the carrier particles obtained in (1) were mixed with a V-blender to obtain a two-component developer.

Comparative Example 13 100 parts of the non-magnetic toner particles obtained in Preparation Example 6, 0.5 parts of hydrophobic silica (R-972) and 0.5 parts of the silicone rubber fine particles obtained in Preparation Example 1 were used in Henschel. The mixture was mixed with a mixer to obtain a non-magnetic toner composition having an external additive attached to the toner surface. 5 parts of this toner composition and 95 parts of the carrier particles obtained in Production Example 7 were mixed with a V-blender to obtain a two-component developer. Comparative Example 14 100 parts of the non-magnetic toner particles obtained in Production Example 6 and 1.0 part of the silicone rubber fine particles obtained in Production Example 10 were mixed with a Henschel mixer, and an external additive was adhered to the toner surface. A magnetic toner composition was obtained. This toner composition 5
Parts and 95 parts of the carrier particles obtained in Production Example 7 were mixed with a V-blender to obtain a two-component developer.

(Evaluation of Developer) The developers obtained in Examples 6 to 11 and Comparative Examples 6 to 14 were evaluated.
For the magnetic toner, the Vivace20 is modified so that it can be transferred by a bias roller and reversal development.
0 (manufactured by Fuji Xerox Co., Ltd.) was used, and the two-component developer was also modified in the same way with the Vivace 50.
0 (manufactured by Fuji Xerox Co., Ltd.) was used for each evaluation. The test environment was 20 ° C. and 50% RH. The continuous copying test was carried out up to 10,000 sheets for the magnetic toner and up to 150,000 sheets for the two-component developer, and evaluated by observing the cleaning property and the adhesion of the toner to the photoconductor. . The image density was measured with a Macbeth densitometer, and the density was 1.3 or more, the density was 1.1 to less than 1.3, with no fog on the copied image.
X shows less than 1.1. The transfer efficiency was evaluated according to the following criteria by transferring the image on the photoconductor to a tape using a solid patch and measuring the weight before and after transferring it to plain paper. Transfer efficiency: ○: 95% or more, △: 90 to less than 95%, ×
Is less than 90%. The image loss during transfer on the OHP sheet was evaluated by observing the character portion and grading as follows. Image omission on OHP sheet: G1 has no image omission, G2 has only a slight image omission (to the extent that it can be seen when enlarged), G3 has some image omission, and G4 has image omission. Regarding the evaluation standard of the cleaning property, ∘ indicates that there is no problem on the image, and × indicates that black streaks and image defects due to poor cleaning are observed.

Table 2 shows the evaluation results of Examples 6 to 11 and Comparative Examples 6 to 14.

[Table 2]

[0044]

By using the toner for developing an electrostatic charge image of the present invention, the filming phenomenon or the like can be prevented in the cleaning step without damaging the surface of the photoconductor or the dielectric and in the cleaning process. It is possible to obtain an image with stable repeatability for a long time without causing this. Further, according to the image forming method of the present invention, transfer efficiency can be improved by forming an image on a transfer body with a transfer roller to which a bias is applied, and image defects are generated regardless of the type of the transfer body. It is possible to maintain high-quality image with no quality for a long time.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noriyoshi Iida 1600 Takematsu, Minamiashigara City, Kanagawa Prefecture, Fuji Xerox Co., Ltd. (72) Kaori Oishi, 1600 Takematsu, Minamiashigara City, Kanagawa Prefecture, Fuji Xerox Co., Ltd.

Claims (3)

[Claims] 1. A toner composition for developing an electrostatic charge image, which comprises adding resin particles treated with oil to toner particles containing a binder and a colorant. 2. The toner composition for developing an electrostatic charge image according to claim 1, wherein the resin fine particles are silicon rubber fine particles. 3. A step of forming a latent image on a latent image carrier, a step of developing the latent image with a developer, a step of transferring the developed toner image to a transfer body, and a toner on the transfer body. In an image forming method having a fixing step of heating and fixing an image, the toner composition for developing an electrostatic image according to claim 1 is used as a developer, and the transfer step is pressure contact transfer from the back surface of a transfer body using a bias roller. An image forming method comprising: