JPS63155155A - Electrostatic developer and electrostatic developing method and image forming method - Google Patents

Abstract

PURPOSE:To obtain good positive electrostatic chargeability and excellent moisture resistance by incorporating fine inorg. particles of which the surfaces are treated by an epoxy group-contg. silicone oil and are further treated by an amino compd. into a titled developer. CONSTITUTION:The fine inorg. particles of which the surfaces are coated by the epoxy group-contg. silicone oil and are further treated by the amino compd. are incorporated into the electrostatic developer. More specifically, the surfaces of the fine inorg. particles are treated by the epoxy group-contg. silicone oil, by which the epoxy group-contg. silicone oil is bonded to the hydrophilic site and negative electrostatically chargeable site on the surface of the fine inorg. particles and is securely held to the surfaces. Since the epoxy group exists therein, the tackiness of the silicone oil is suppressed low. As a result, the hydrophobic property of a good state is imparted to the fine inorg. particles by the epoxy group-contg. silicone oil and since the surfaces of the fine inorg. particles are further treated by the amino compd. the positive electrostatic chargeability is imparted to the fine inorg. particles.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an electrostatic image used for developing an electrostatic latent image formed in electrophotography, electrostatic recording, electrostatic printing, etc. developer, and organic light using this electrostatic image developer.
i! A':! : An electrostatic image developing method for developing an electrostatic latent image formed on the surface of a photoreceptor made of an L-based semiconductor, and forming an image using these electrostatic image developers and electrostatic image developing methods. The present invention relates to an image forming method, and is particularly suitable for developing a negative electrostatic latent image formed on the surface of a photoreceptor made of an organic photoconductive semiconductor, an electrostatic image developer, an electrostatic image developing method, and an image. This relates to a forming method.

[Background of the invention]

Generally, in electrophotography, a photoreceptor having a photosensitive layer made of a photoconductive material is given a uniform electrostatic charge, and then an electrostatic latent image is formed on the surface of the photoreceptor by performing image exposure. This electrostatic latent image is developed with a developer to form a toner image. The obtained toner image is transferred to a transfer material such as paper and then fixed by heating or pressure to form a copy image.

Examples of the photoconductive material used to form the photosensitive layer of the photoreceptor include inorganic photoconductive materials such as selenium, zinc oxide, and cadmium sulfide, and organic photoconductive materials made of high molecular compounds or low molecular weight compounds such as polyvinyl carbazole. There are known materials such as carbonaceous materials.

However, although photoreceptors having photosensitive layers formed from these photoconductive materials have one advantage in forming electrostatic latent images, they also have drawbacks specific to various photoreceptors. have.

For example, in a photoreceptor having a photosensitive layer formed of selenium, the photosensitive layer easily crystallizes due to heat or a total reflux compound contained in a developer or transfer material, deteriorating its properties, and the electrostatic potential There is a problem that the potential of the image decreases, resulting in a decrease in image resolution or partial image blanking. In addition, under high humidity environmental conditions, the photoconductivity of the photosensitive layer decreases and static charges remain in the non-image areas of the photoreceptor, resulting in fogging and making it difficult to obtain clear images. However, under such environmental conditions, it is not possible to form good images many times, and the durability is low.

Additionally, photoreceptors having a photosensitive layer formed of cadmium sulfide or a photoreceptor having a photosensitive layer formed of zinc oxide typically have a photoconductive material, ie, cadmium sulfide or zinc oxide, dispersed in a binder resin. A photosensitive layer is formed, but it is quite difficult to uniformly disperse such a photoconductive material in the form of fine particles in a binder resin, and as a result, the resulting photoreceptor has low sensitivity and is unsuitable for high-speed copying. In addition, the photosensitive layer tends to deteriorate early in the corona charging process or exposure process that is normally used to form an electrostatic latent image, making it difficult to form a good image over a long period of time. Furthermore, under high-temperature environmental conditions, the characteristics of the photosensitive layer change due to moisture, making it impossible to obtain the desired potential of the electrostatic latent image, resulting in a low image density. be.

On the other hand, organic photoreceptors having a photosensitive layer formed from a polymeric photoconductive material typified by polyvinylcarbazole have good film-forming properties and can be manufactured at low cost. It has been attracting attention in recent years due to its advantages such as non-toxicity to z2 or Since the charge retention ability is easily changed, it is still inferior to photoreceptors having a photosensitive layer made of an inorganic photoconductive material, and the development of a high-performance photoconductive material is desired.

On the other hand, in order to overcome the above problems, it has recently been proposed to use low molecular weight organic photoconductive materials. Since the low molecular weight organic photoconductive material has good dispersibility in the binder resin, the resulting photosensitive layer has the organic photoconductive material uniformly dispersed in the form of fine particles. It is possible to obtain a photoreceptor with relatively high sensitivity, and by forming the photoreceptor layer by dispersing an organic photoconductive material in a binder resin, film forming properties are good, so the photoreceptor can be manufactured with high productivity. There are many types of low-molecular-weight photoconductive materials that can be manufactured and used, and therefore, by using appropriately selected low-molecular-weight photoconductive materials, it is possible to create a photoconductor with superior performance than conventional ones. It is possible to get a good deal. Thus, an organic photoreceptor having a photosensitive layer formed of a low molecular weight photoconductive material is preferable to conventional photoreceptors.

However, since organic photoconductive materials usually exhibit photoconductivity through the movement of positive charges, it is difficult to form photoconductive materials on the surface of an organic photoreceptor that has a photosensitive layer formed from the organic photoconductive material. The polarity of the electrostatic latent image is preferably negative. In order to develop a negative electrostatic latent image, it is necessary to use a developer containing positively charged toner.

However, in the conventionally widely used photoreceptor having a photosensitive layer made of selenium, etc., the polarity of the electrostatic latent image formed on the surface is positive, so it is difficult to develop the electrostatic latent image. Developers containing negatively charged toner are used, and considerable research and development efforts have been made on developing agents containing negatively charged toner. Research and development of developers containing toner is still lagging behind, and it is true that a developer containing a sufficient amount of positively charged toner has not been obtained.

On the other hand, wet developing methods and dry developing methods are known as methods for developing electrostatic latent images. The former wet development method is
Since a liquid developer is used, there is a problem in that it emits a bad odor, and there is also a problem in that high-speed copying is difficult because high energy is required to dry the transfer material. The latter dry developing method does not have such problems and can be preferably used as a developing method for electrostatic latent images.

Developers used in the dry development method include so-called 1-component developers that are made only of magnetic toner containing a magnetic substance, and so-called 2-component developers that are made of a non-Lif toner that does not contain a magnetic substance and a magnetic carrier. Component-based developers are known.

The former one-component developer consists only of n-type toner and does not have a carrier, so it regulates the slight frictional electrification caused by the toners and the height of the toner and the developing sleeve or developer layer placed in the developing device. The toner is charged by frictional charging with a regulating blade, etc., and as a result, both positively charged toner and negatively charged toner exist, and since the amount of triboelectric charge is small, basically development is not possible. There is a problem that it tends to become unstable. Specifically, for example, toner may adhere to non-image areas on the photoreceptor,
There is a problem that fog occurs in the final fixed image, or the amount of toner adhering to the image area on the photoreceptor becomes insufficient, resulting in a low density of the final fixed image.

In addition, the magnetic material used in magnetic toner usually has hydrophilic properties, and since this hydrophilic magnetic material is often contained in an exposed state on the surface of toner particles, the toner becomes triboelectrically charged due to moisture. Charge tends to leak, and in a high 1 SO atmosphere, electrostatic transfer to transfer paper, which is normally used as a transfer material, becomes poor during the transfer process, resulting in a low toner transfer rate to the transfer paper. As a result, there are problems in that the quality of the final fixed image decreases and image blanking occurs. In addition, since the magnetic material used in magnetic toner usually has negative chargeability, it is difficult to positively charge the magnetic toner with an appropriate amount of charge. As a result, there is a problem that the final fixed image has a decrease in 4 degrees, and also causes unevenness and missing images.

On the other hand, the latter two-component developer is composed of toner and carrier, and the carrier has the function of charging the toner to a desired polarity, so it is possible to charge the toner with the appropriate polarity and appropriate charging. FZ triboelectric charge can be imparted using TLi, and it is possible to obtain a developer having much superior triboelectricity compared to the one-component developer described above. Further, by selecting a carrier having desired characteristics, it is possible to control the amount of charge of the toner to a considerable extent.

However, in order to obtain a good final fixed image, it is not enough that the developer has good triboelectric chargeability, and particles of the developer to which triboelectric charge has been applied do not aggregate in the developing device. It is necessary that the film be transported to the developing space in good condition without any damage.

For example, in the magnetic blank development method, 1. Stir inside the developing device! As a result of being triboelectrically charged 7S, the charged developer is carried in the developing sleeve L in the form of a thin layer arranged in a uniform brush shape, and the developer layer in such a form is It is necessary to stably transport the film to the developing space while holding it.

For example, in a one-component developer, since it consists only of magnetic toner and does not have a carrier, this SSN toner is
The magnetic cohesive force and electrostatic cohesive force are strong, and as a result, the magnetic toner coagulates and forms clumps, reducing the fluidity of the developer. As a result, the magnetic toner is uniformly arranged on the developing sleeve in a thin, brush-like manner. There is a problem that it is difficult to support it in a layered form. In addition, since the magnetic toner tends to form agglomerates, frictional electrification between the magnetic toners or between the magnetic toner and the wall, regulating blade, developing sleeve, etc. inside the developing device is not achieved properly. As a result, there is a problem that the final fixed image becomes unclear with a lot of fog.

In addition, for example, in a two-component developer, if the toner tends to aggregate and form lumps due to electrostatic cohesive force, it becomes difficult to disperse the toner particles in the carrier particles with a uniform seismic intensity. As a result, the frictional electrification between toner and carrier decreases, and the proportion of toner with low frictional band overlap increases.In the developing process, toner adheres to non-image areas on the photoreceptor, causing fog in the final fixed image. In addition, there is a large amount of weakly charged toner, and the electrostatic adhesion between the toner and the carrier becomes small. Therefore, in the magnetic brush development method, the carrier particles adhere to the carrier particles while being rotated by magnetic force. When toner particles are transported to the developing space, the centrifugal force caused by the rotation of the carrier particles causes the toner particles to scatter, resulting in contamination of the charger, exposure optical system, and other equipment installed in the copier. However, there is a problem in that image defects such as image unevenness and missing images occur in the final fixed image.

However, in conventional negatively charged toners, fine silica particles having a smaller diameter than the toner particles are mixed with the toner particles to attach the fine silica particles to the surface of the toner particles, thereby preventing the toner from clumping. This is done to obtain high liquidity.

However, conventionally used silica fine particles have strong negative chargeability, so when obtaining a positively chargeable toner, if silica fine particles are mixed with the toner and attached to the surface of the toner particles, the resulting toner will be negatively charged. It becomes electrostatic,
As a result, the polarity becomes the same as the negative electrostatic latent image formed on the photoreceptor, and there is a problem that electrostatic development cannot be performed.

The following techniques have been disclosed as techniques for solving such problems.

(1) A technique using positively charged fine particles treated with a silane coupling agent (see JP-A-53-66235, JP-A-56-123550, and JP-B-Sho 53-22447).

(2) Technology using positively charged fine particles treated with silicone oil (JP-A-58-60754, JP-A-58-59)
(Refer to Publication No.-187359).

[Problem that the invention seeks to solve]

However, as in techniques (1) and (2) above, positively charged fine particles treated with a silane coupling agent or silicone oil are used, mixed with the toner, and attached to the surface of the toner particles. However, when subjected to physical force such as agitation in the developing device, the fine particles become scattered from the surface of the toner particles, and as a result, the toner is not positively charged by friction with an appropriate amount of charge, and it also scatters. Fine particles become physically or electrostatically attached to the inner wall of the developing device, the developing sleeve disposed inside the developing device, the regulating blade, the surface of carrier particles, etc., and the triboelectric charging properties of the toner are inhibited. If the accumulation due to adhesion becomes excessive, the fine particles and toner particles will be triboelectrically charged, and the toner particles will become oppositely charged, that is, negatively charged, resulting in the toner scattering and contaminating the inside of the device. In the final fixed image, there are problems such as fogging and a decrease in image quality, resulting in an unclear image.

Further, when image formation is repeated many times, the image gradually becomes less clear, resulting in a defective image at an early stage, resulting in low durability.

In particular, when using fine particles treated with a silane coupling agent, it is difficult to completely cover the surface of the fine particles with the silane coupling agent, and as a result, negatively charged sites and hydrophilic sites of the fine particles remain. , the positive chargeability of the toner decreases due to the remaining negatively chargeable sites,
Furthermore, the toner becomes negatively chargeable, resulting in more fogging in the final fixed image, and due to the remaining hydrophilic sites, it becomes more susceptible to the effects of humidity, and as a result, its triboelectric charging ability decreases when environmental conditions change. It becomes unstable,
As a result, the inside of the device becomes contaminated due to toner scattering, fog occurs in the final fixed image, image density decreases due to a decrease in transfer rate in the transfer process, and image unevenness occurs due to toner scattering. , there is a problem that the image becomes unclear.

In addition, especially when using fine particles treated with silicone oil, the surface of the fine particles is covered with a sticky oily substance, so such fine particles are mixed with the toner to coat the surface of the toner particles. It is difficult to improve the fluidity of the toner even if it is attached to the toner, physical aggregation may occur due to silicone oil, and fine particles may adhere to the inner wall of the developing device, the developing sleeve, the regulating blade, etc. The problem is that the positive charging ability of the toner is reduced, the resulting image quality is reduced, and contamination due to toner scattering occurs, resulting in the final fixed image being unclear with a lot of fog and image gaps. be.

In addition, in the image forming process, the toner image formed on the surface of the photoreceptor through the development process is subjected to a transfer process, and in this transfer process, it is transferred to a transfer material made of ordinary paper or the like. As the transfer means, it is preferable to use electrostatic transfer means that utilizes electrostatic force.

However, as in the techniques (1) and (2) above, a toner image formed on the surface of a photoreceptor by being developed with a toner composed of fine particles treated with a silane coupling agent or silicone oil is Due to the insufficient amount of charge and the strong adhesion to the surface of the photoreceptor, it is difficult to transfer it well with some electrostatic transfer means, resulting in uneven images and missing images in the final fixed image. There is a problem that the quality of the image decreases.

Further, the photoconductor after the toner image has been transferred in the transfer process is then subjected to a cleaning process, in which the toner remaining on the surface of the photoconductor after the transfer process is removed, and the surface of the photoconductor is cleaned. Cleaned. However, as in the techniques (1) and (2) above, toners made using fine particles treated with a silane camping agent or silicone oil are not physically or electrostatically attached to the surface of the photoreceptor. Due to the large adhesion force, it is difficult to completely clean the residual toner, and as a result, some of the toner remains on the photoreceptor and has a negative impact on the next image formation, causing the problem that the image becomes unclear. .

Further, the transfer material to which the toner image has been transferred in the transfer step is subjected to a fixing step, in which the toner image is fixed to the transfer material by being heated or pressurized by a heat roller.
A final fixed image is formed.

However, as in the techniques (1) and (2) above, toner composed of fine particles treated with a silane coupling agent or silicone oil tends to transfer and adhere to the surface of the heated roller. Therefore, a so-called offset phenomenon occurs in which the toner adhering to the heat roller transfers to the next transfer material and stains the image, and when the toner adhering to the heat roller solidifies, this causes the heat roller to There is a problem in that the surface is scratched and the durability of the heat roller is significantly reduced.

[Purpose of the invention]

The present invention has been made based on the above-mentioned circumstances, and its objects are: (1) to provide an electrostatic image developer having good positive chargeability and excellent moisture resistance; 2) To provide an electrostatic image developing method capable of satisfactorily developing a negative electrostatic latent image formed on an organic photoreceptor without scattering of developer particles; (3) environmentally friendly. Good ii with high image quality and no fog without being influenced by the conditions! An object of the present invention is to provide an image forming method capable of stably forming a 1iTt image many times.

[Means for solving problems]

The electrostatic image developer of the present invention contains inorganic fine particles (hereinafter also referred to as "specific Ja-free fine particles") whose surface has been treated with a silicone oil containing an epoxy group and further treated with an amino compound. It is characterized by being

In the electrostatic image developing method of the present invention, a negative electrostatic latent image formed on the surface of a photoreceptor (hereinafter also referred to as "organic photoreceptor") made of an organic photoconductive semiconductor is transferred to the specific inorganic fine particles. It is characterized in that development is carried out using an electrostatic image developer containing.

The image forming method of the present invention includes a latent image forming step of forming a negative electrostatic latent image on the surface of a mechanistic light body; A developing step of developing with an image developer, a transfer step of electrostatically transferring the toner image obtained by the development to a transfer material, and a cleaning blade to clean the developer remaining on the surface of the organic photoreceptor after the transfer step. and a fixing step of heating and fixing the toner image on the transfer material using a heat roller fixing device having a heat roller coated with a fluororesin or a silicone resin. .

[Function and effect of the invention]

Since the electrostatic image developer of the present invention contains specific II-free particles, it has good positive chargeability and excellent moisture resistance. That is, when the surface of the inorganic fine particles is treated with silicone oil having an epoxy group, the silicone oil having an epoxy group binds to the hydrophilic sites and negatively charged sites on the surface of the inorganic fine particles, and this binds firmly to the surface. Moreover, the presence of epoxy groups suppresses the tackiness of the silicone oil, and as a result, the silicone oil with epoxy groups imparts good hydrophobicity to the inorganic fine particles, and this By further treating the surface of the inorganic fine particles with an amino compound, the inorganic fine particles are given positive chargeability, resulting in a high 7! Even under environmental conditions, the positive chargeability of the inorganic fine particles is stably exhibited, and a developer with excellent positive chargeability can be obtained.

In addition, the above-mentioned specific R-free fine particles have good adhesion to the developer and are firmly held by the developer particles, so that when the developer is stirred in the developing device, the specific This prevents inorganic fine particles from transferring and adhering to the inner wall of the developing device, developing sleeve, regulating blade, etc.
As a result, the developer exhibits stable positive chargeability even when image forming processes are performed many times. Since the specific inorganic fine particles impart high fluidity to the developer, the developer particles do not aggregate and are triboelectrically charged in a stable state.

According to the electrostatic image developing method of the present invention, a negative electrostatic latent image is formed on the surface of a photoreceptor made of an organic photoconductive semiconductor by an electrostatic image developer containing the above-mentioned specific inorganic fine particles. In order to develop a negative electrostatic latent image formed on the organic photoreceptor, the negative electrostatic latent image formed on the organic photoreceptor can be developed without scattering of developer particles, without sacrificing the advantages of the organic photoreceptor, which is low production cost and non-toxicity. It can be developed well. In other words, since the above-mentioned developer has excellent positive chargeability, it becomes positively charged by an appropriately charged crab, and therefore, the developer particles are stably held in the development sleeve and enter the development space. This makes it possible to prevent contamination caused by scattering of developer particles.

In addition, as mentioned above, the fluidity of the developer is excellent, so it is possible to form a uniform magnetic blanket of developer on the developing sleeve, and therefore good development can be achieved using the magnetic brush development method. It becomes possible to do so.

According to the image forming method of the present invention, since the electrostatic image developer contains the above-mentioned specific inorganic fine particles and has excellent positive chargeability, in the developing step, the non-image on the organic photoreceptor is As a result, it is possible to obtain a clear image without fog in the final fixed image. In addition, since the specific inorganic fine particles give the developer suitable releasability, the physical adhesion to the surface of the organic photoreceptor is small. Transfer can be performed, and it is possible to form a clear image with high image density and no image unevenness. In addition, since the developer has good transferability as mentioned above, only a small amount of developer remains on the organic photoreceptor after the transfer process, and therefore, the remaining developer can be easily cleaned in the cleaning process. Moreover, as mentioned above, the developer has suitable mold releasability, so the adhesion of the developer to the organic photoreceptor is small, and as a result, the developer can be easily cleaned using a cleaning blade. becomes possible. Furthermore, since the cleaning properties of the developer are good,
Good leaning can be achieved with a small pressure contact force of the cleaning blade against the photoreceptor, thus preventing the surface of the organic photoreceptor from being abraded by the cleaning blade and causing early deterioration of the characteristics of the organic photoreceptor. This can significantly extend the service life of the organophotoreceptor. In addition, in the fixing process, the specific R'l& particles are present between the surface of the molten developer and the heat roller, so that the specific inorganic fine particles provide a mold release effect, and the developer This prevents the transfer and adhesion of the developer to the heat roller, and also prevents the accumulation of developer in the minute grooves of the heat roller. This further prevents transfer and adhesion to the image, and as a result, it is possible to prevent image staining caused by the offset phenomenon. In addition, since the surface of the specific inorganic fine particles is covered with silicone oil having an epoxy group and further covered with an amino compound, there is little risk that the surface of the heat roller will be damaged by the specific 8g-free fine particles. It is possible to significantly extend the service life of the material, and excellent anti-offset properties can be stably obtained over a long period of time.

[Specific structure of the invention]

The electrostatic image developer of the present invention has a surface treated with a silicone oil having an epoxy group, and further contains non-k particles that have been treated with an amine compound.

As the silicone oil having an epoxy group, for example, one represented by the following general formula (1) can be used.

General formula (1) (R represents an alkylene group or an aryl group, x, y
each represents an integer of 1 or more. ) Furthermore, the silicone oil having an epoxy group preferably has an epoxy equivalent in the range of 200 to 10,000, and preferably has a viscosity at 25° C. in the range of 40 to 20,000 cρS.

If the epoxy equivalent is too small, stable positive triboelectric charging properties may not be obtained, causing fogging or reduced durability.On the other hand, if the epoxy equivalent is too large, the durability may deteriorate! performance and durability may decrease. In addition, when the viscosity is too low, durability may decrease due to increased stickiness, while when the viscosity is too high, the surface treatment of the inorganic fine particles becomes poor, and as a result, the triboelectric charging properties of the pressure become unstable. , the durability may decrease.

As the specific substance of the silicone oil having an epoxy group, for example, commercially available products shown in Table 1 below can be preferably used.

Table 1 Examples of the amino compounds include diethylenetriamine, dipropylenetriamine, triethylenetetramine, tetraethylenepentamine, dimethylaminopropylamine, diethylaminopropylamine, dibutylaminopropylamine, hexamethylenediamine, N-aminoethylpiperazine, bis -Aminopropylpiperazine, trimethylhexamethylenediamine, bis-(hexamethylene)triamine, ethanolamine, triethanolamine, jetanolamine, cetylpyridinium chloride, butylamine, triethylamine, aniline, pyridino, methylizine trisaniline, 4.4 ',
4”-Methyridine tris (N.

Organic primary amines such as N dimethylaniline), secondary
Class amines, tertiary amines, salts thereof, etc. can be used. Further, metal complexes containing nitrogen atoms can also be used.

In the present invention, the surface of the inorganic fine particles is first treated with a silicone oil having an epoxy group, and then the surface treated with the silicone oil having an epoxy group is further treated with an amine compound. By treating the surface of the inorganic fine particles in this order, the treated inorganic fine particles have good hydrophobicity and good positive chargeability.

That is, by first treating the surface of the R-free fine particles with a silicone oil having an epoxy group, the silicone oil having an epoxy group binds to the hydrophilic sites or negatively charged sites of the inorganic fine particles, and these are firmly held. As a result, the epoxy group-containing silicone oil imparts hydrophobicity to the inorganic fine particles in a suitable state, and by further treating the hydrophobically imparted surface with an amine compound, the inorganic fine particles become most suitable. The amine compound is ensured to exist in the outer layer, and since the amine compound is reactive with silicone oil that has epoxy groups, the amine compound is strongly retained, and the epoxy group is also present. As a result, the development of stickiness of silicone oil is suppressed to a small level, and as a result, the amine compound imparts positive chargeability to the inorganic fine particles, and as a result, the inorganic fine particles have excellent impact resistance, moisture resistance, mold releasability, and positive chargeability. It becomes something.

Examples of a-free fine particles whose surface is treated with the silicone oil having an epoxy group and further with an amino compound include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, and zinc oxide. , chromium oxide, cerium oxide, antimony dioxide, zirconium oxide, silicon carbide, and the like. It is preferable that the average particle size of the primary particles (particles separated into individual unit particles) of such inorganic fine particles is within the range of 3 u to 2 fl.

In particular, silica particles can be preferably used as the inorganic particles. Silica fine particles are 5i-0-5i
Fine particles having a bond may be produced by either a dry method or a wet method, but those produced by a dry method are preferable, and in particular, silica fine particles produced by vapor phase oxidation of a silicon halide compound. It is preferable that In addition, as silica fine particles, silicon dioxide (
silica), aluminum silicate, sodium silicate, calcium silicate, potassium silicate, zinc silicate,
Although fine particles made of silicate such as magnesium silicate may be used, those containing 85% by weight or more of 5iOt are preferable.

As a method for treating the surface of the inorganic fine particles with a silicone oil having an epoxy group and further with an amino compound, a known technique can be used, and the method is not particularly limited. Specifically, it can be processed as follows.

(1) A method of dispersing inorganic particles in a solution of silicone oil containing an epoxy group dissolved in a container, removing the solvent by filtration or spray drying, and then hardening by heating, or fluidization. Using a head device, a solution prepared by dissolving silicone oil having an epoxy group in a solvent is sprayed onto inorganic fine particles, and then heated and dried to remove the solvent and harden the film. The surface of the fine particles is treated with silicone oil having an epoxy group.

(2) Next, the surface of the inorganic fine particles treated with the epoxy group-containing silicone oil is further treated with an amino compound by the same method as above.

The particle size of the inorganic fine particles obtained in this way, the surface of which was treated with silicone oil having an epoxy group and then with an amino compound, is such that the average particle size of the primary particles is 31 μm.
~2μ, particularly preferably within the range of 51p to 500 mμ. In addition, the specific surface area according to the BET method is
It is preferably 20 to 500 mz/g. If the average particle diameter is too small or the specific surface area is too large, the SaW particles may easily slip through during cleaning using a blade-type cleaning device, resulting in poor cleaning. On the other hand, when the average particle diameter is too large or the specific surface area is too small, the fluidity of the developer decreases, resulting in poor developability, which may result in a decrease in image density or the occurrence of image unevenness.

When constituting an l-component developer, the specific inorganic fine particles are mixed with the magnetic toner particles and contained in a state where they are attached or implanted onto the surface of the magnetic toner particles. Further, in the case of forming a two-component developer, the specific inorganic fine particles are mixed with the particle powder of the non-magnetic toner and are contained in a state where they are attached or implanted on the surface of the non-magnetic toner particles, More career to this? It is combined.

The content ratio of the specific Ja-free fine particles is 0.1% of the toner.
It is preferably 5% by weight, particularly preferably 0.1 to 2% by weight. When the content ratio of the specific inorganic fine particles is too small, the fluidity of the developer may decrease, resulting in poor triboelectric charging properties of the toner, and it is difficult to impart an appropriate positive charge to the toner. This may result in fogging or image unevenness. Furthermore, when the content ratio is excessive, some of the specific inorganic fine particles may exist in a free state from the toner particles, and as a result, the specific inorganic fine particles in mM may adhere to and transfer to the carrier particles, or The toner adheres to the inner wall of the developing device, the developing sleeve, the regulation blade, etc., and as a result, the triboelectricity of the toner becomes poor at an early stage, making it difficult to apply an appropriate amount of positive charge to the toner, resulting in fogging and A decrease in image density may occur.

The electrostatic image developer of the present invention may basically be a one-component developer consisting only of magnetic toner, or a two-component developer consisting of a non-magnetic toner and a magnetic carrier. Although it may be used, a two-component developer is particularly preferred.

The non-magnetic toner is a particle powder containing a colorant and other additives in a binder, and the magnetic toner is a particle powder containing a colorant, a magnetic substance, and other additives in a binder. It is a particulate powder composed of The average particle size of the toner is usually preferably about 5 to 20 μm. Other additives that can be used include, for example, a fixability improver, a charge control jII agent, a cleaning performance improver, and the like.

The binder for the toner is not particularly limited, and resins conventionally used for this type of use can be used. Specifically, for example, polystyrene resins, copolymers obtained from at least two or more monomers selected from styrene monomers, 81 acrylic esters, and methacrylic ester monomers, and polystyrene-butadiene resins. , polyester resin, epoxy resin, polyamide resin, polyurethane resin, etc. can be used.

Among these, those that do not inhibit the positive chargeability of the toner are:
In particular, polystyrene resins, styrene monomers, acrylic esters m1, and methacrylic esters ju
A copolymer obtained from at least two types of monomers selected from t-isomers can be preferably used.

Examples of colorants include carbon black, phthalocyanine blue, benzidine yellow, nigronon dye, aniline blue, calco oil blue, chrome yellow,
Dyes and pigments such as ultramarine blue, denibon oil, quinoline yellow, methylene blue chloride, malachite green offsalate, lamp black, and rose bengal can be used. These substances may be used alone or in combination, and the content of the colorant is usually preferably 1 to 15% by weight of the toner.

Examples of fixing property improvers include polyolefins, fatty acid metal salts, fatty acid esters and fatty acid ester waxes, higher fatty acids, higher alcohols, liquid or solid paraffin waxes, amide waxes, polyhydric alcohol esters, silicone resins, and aliphatic fluorocarbons. etc. can be used.

As the charge control agent, for example, a metal complex dye or the like can be used.

As the cleaning property improver, for example, fatty acid metal salts such as zinc stearate, calcium stearate, and stearic acid, and polymer particles such as methyl methacrylate particles and styrene particles can be used.

When the toner is a magnetic toner, a magnetic material is contained in the binder. This magnetic material has an average particle size of 0.1~
It is preferable that the binder be uniformly dispersed and contained in the binder in the form of a fine powder of l ma.

Further, the content of the magnetic material is usually preferably 10 to 70 parts by weight, particularly preferably 20 to 50 parts by weight, based on 100 parts by weight of the toner. Such magnetic materials include iron, ferrite, magnetite, and other ferromagnetic metals or alloys such as cobalt, nickel, etc., or compounds containing these elements, and materials that do not contain ferromagnetic elements but are subjected to appropriate heat treatment. Alloys that exhibit ferromagnetic properties, such as manganese-copper-aluminum,
A type of alloy called Heusler alloy containing manganese and copper such as manganese-copper-tin, chromium dioxide, and others can be used.

When the electrostatic image developer of the present invention is a two-component developer,
The carrier used in combination with the non-magnetic toner is not particularly limited.

Specifically, carriers made of magnetic particles, resin-coated carriers in which the surface of magnetic particles are coated with a specific resin, or magnetic fine particle dispersion in which fine magnetic particles are dispersed in resin particles. A mold carrier or the like can be used.

As the magnetic material used for the carrier, for example, ferromagnetic metals or alloys such as iron, ferrite, magnetite, cobalt, nickel, etc., or compounds containing these elements, etc. can be used. The average particle size of the carrier is usually preferably about 10 to 500 nm, particularly preferably 20 to 200 μm. If the average particle size of the carrier is too small, an electrostatic latent image, that is, a phenomenon in which carrier particles adhere to the image area, may occur, resulting in a defective image.If the average particle size of the carrier is too large, the toner may be rubbed The surface area for charging becomes smaller, and as a result, the amount of poorly charged toner increases and image unevenness may occur.

Next, the electrostatic image developing method of the present invention will be explained.

In the electrostatic image developing method of the present invention, a negative electrostatic latent image formed on the surface of an organic photoreceptor is transferred to an electrostatic image developer containing the specific inorganic fine particles (hereinafter referred to as "specific developer ) to form a toner image.

The organic photoreceptor is usually constructed by laminating a photosensitive layer containing a photoconductive layer made of an organic compound and a thick conductor on a conductive support. The photosensitive layer may be composed only of a photoconductive semiconductor made of an organic compound, or may be composed of the photoconductive semiconductor dispersed in a binder made of a resin.

The photosensitive layer includes a carrier generation layer containing a carrier generation substance that absorbs visible light and generates charged carriers, and a carrier generation layer that transports either or both of positive and negative carriers generated in this carrier generation layer. It is preferable to use a so-called functionally separated type photosensitive layer configured by combining a carrier transport layer containing a carrier transport substance. In this way, by assigning the two basic functions necessary for the photosensitive layer, namely carrier generation and carrier transport, to separate layers, the range of materials that can be used in the composition of the photosensitive layer is widened, and each It becomes possible to independently select the substance or material system that optimally performs the function.
In addition, by doing so, it can meet the various properties required in the image forming process, such as high surface potential when charged, high charge retention capacity, high photosensitivity, and high stability during repeated use. It becomes possible to construct an organic photoreceptor having such characteristics.

As the carrier-generating material in the photosensitive layer, for example, anthrone pigments, perylene derivatives, phthalocyanine pigments, azo dyes, indigoid dyes, etc. can be used. Examples of carrier transport substances include carbazole derivatives, oxadiazole AM 4, triarylamine derivatives, and polyarylalkane M'J=
In addition, hydrazone 231, pyrazoline mR, stilhen MR, styryl triarylamine derivatives, etc. can be used. The thickness of the carrier generation layer is usually 0.
．． The thickness of the carrier transport layer is preferably 1 to 30 μm.

When forming a photosensitive layer by dispersing a photoconductive semiconductor made of an organic compound in a binder made of M resin, examples of resins that can be used as the binder include polyethylene, polypropylene, acrylic resin, and methacrylic resin. , vinyl chloride resin, vinyl acetate resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, polycarbonate resin, silicone resin, melamine resin, addition polymerization type resin, polyaddition type resin, polycondensation type resin, and Copolymer resins containing two or more of the repeating units of these resins, such as vinyl chloride-vinyl acetate copolymer resins, vinyl chloride-vinyl acetate-maleic anhydride copolymer resins,
Examples include insulating resins such as styrene-acrylic copolymer resins, and polymeric organic semiconductors such as poly-N-vinylcarbazole.

In the organic photoreceptor, a metal sheet made of, for example, aluminum, nickel, copper, zinc, palladium, silver, indium, tin, platinum, gold, stainless steel, steel, brass, etc. can be used as the conductive support.

The specific structure of the organic photoreceptor is not particularly limited, and various structures can be adopted. Further, an organic photoreceptor whose surface potential when charged is, for example, -400 to -1000 V can be particularly preferably used.

FIG. 1 is an explanatory diagram showing an example of a developing device that can be suitably used to carry out the electrostatic image developing method of the present invention.

IO is an a-conductor photoreceptor, and this organic photoreceptor 10 has a rotating drum-like form that is rotated in the direction of arrow The photosensitive layer 10B containing a semiconductor is laminated. A charger and an exposure optical system (not shown) are arranged upstream of the development space 24, and the charger first sets the surface of the organic photoreceptor 10 to be developed at a temperature of -400 to -1, for example.
It is charged to a constant negative potential within the range of 000V,
Next, an optical image of the document is created by an exposure optical system (not shown).
9 is projected onto the surface to be developed of the light body lO to form an electrostatic latent image corresponding to the original on the surface to be developed, and this electrostatic latent image is moved to the development space 24, where the electrostatic latent image is The latent image is developed.

11 is a developing sleeve, and this developing sleeve 11 is
The developing sleeve 11 has a rotating drum shape made of a non-magnetic material such as aluminum, and a magnet 12 is disposed inside the developing sleeve 11 . This magnet body 12 consists of a plurality of N and S magnetic poles arranged along the circumference of the developing sleeve 11. These developing sleeve 11 and magnet body 12 constitute a developer transport carrier, and in a specific example,
The developing sleeve 11 is rotated to move, for example, in the direction of arrow Y, that is, in the same direction as the moving direction of the organic photoreceptor IO in the developing space 24, and the magnet body 12 is fixed, for example. In the present invention, the rotation direction of the developing sleeve 11 is not particularly limited, and the magnet body 12 may be rotated in an appropriate direction.

The N and S magnetic poles constituting the magnet body 12 are magnetized so that the magnetic flux density on the surface of the developing sleeve is usually about 500 to 1,500 Gauss, and the particles of the developer 22 are distributed on the surface of the developing sleeve 11 by the magnetic force. A developer N ([air brush] 23) is formed in a state where it stands up like a brush.

Reference numeral 13 denotes a regulating plate, and this regulating blade 13 is made of a magnetic or non-magnetic material and is used to regulate the height and amount of the developer layer 23 reaching the developing space 24. Reference numeral 14 denotes a cleaning blade, and this cleaning blade 14 is used to scrape off and remove the developer remaining on the surface of the developing sleeve 11 after development. The surface of the developing sleeve 11 that has been cleaned by the cleaning blade 14 comes into contact with the developer 22 again in the developer reservoir 15, and a new magnetic brush is formed on the surface, and after this magnetic brush is regulated by the regulating blade 13, it enters the developing space. 24.

15 is a developer reservoir; 16 is a stirring screw; in the developer reservoir 15, toner and carrier constituting the developer 22 are mixed and dispersed by the stirring screw 16;
This makes it possible to make the toner 4 degrees uniform. Also,
The carrier of the developer 22 is used repeatedly, whereas the toner is consumed each time development is performed. Therefore, new toner in the toner impeller 17 is transferred to the developer reservoir 15 by the supply roller having a recessed portion on its surface. will be replenished accordingly.

Reference numeral 19 denotes a bias power supply, and 20 denotes a protective resistor. The bias power supply 19 applies a bias voltage necessary for development to the developing sleeve 11 via the protective resistor 20. This bias voltage is preferably a DC voltage of about 50 to 500V, for example.

In developing an electrostatic latent image, it is preferable that the tip of the magnetic brush make shallow contact with the surface of the photoreceptor 10 in order to achieve uniform development. The distance between them (Hcut) is preferably about 0.8 times the gap (Dsd) between the organic photoreceptor 10 and the developing sleeve 11 in the developing space 24. Further, the gap (D sd) is, for example, 0.1
It is preferable to set it to 4.01. When the gap (Dsd) is too small, developability may deteriorate; on the other hand,
When the gap (Dsd) is too large, toner scattering tends to occur and the image may become unclear.

In the apparatus configured as described above, when the developing sleeve 11 rotates, the magnitude and direction of the magnetic field on its surface sequentially change, so that the carrier particles in the magnetic brush formed on the surface of the developing sleeve 11 rotate and vibrate. However, following the rotational movement of the developing sleeve 11, the toner particles are moved into the developing space 24, and as a result, the toner particles attached to the surface of the carrier particles by electrostatic force are conveyed to the developing space 24.

Next, the image forming method of the present invention will be explained.

In the image forming method of the present invention, a negative electrostatic latent image is formed on the surface of the m-containing photoreceptor (WI image forming step), this electrostatic latent image is developed with the specific developer (developing step),
The toner image obtained by development is electrostatically transferred to a transfer material (transfer step), and the toner image on the transfer material is heated in contact with a heat roller coated with fluororesin or silicone resin to fix it properly. step) to form a fixed visible image, and on the other hand, after the transfer step, the
The developer remaining on the surface of the photoreceptor is cleaned using a cleaning blade (cleaning step) to restore the surface of the organic photoreceptor to its original clean state.

In the latent image forming step, the surface of the organic photoreceptor is charged to a uniform negative potential (charging step), and then a light image of the document is projected onto the charged surface of the photoreceptor (exposure step).
As a result, an electrostatic latent image made of electrostatic charges is formed on the surface of the organic photoreceptor.

Specifically, in the charging step, the entire image forming area on the surface of the organic photoreceptor is charged to a potential of, for example, about -400 to -1000V using, for example, a corona charger, and in the exposure step, the charging An exposure optical system comprising, for example, a light source, a reflecting mirror, and a lens produces a reflected light image or a transmitted light image of the document on the surface of the organic photoreceptor whose surface is charged to a uniform negative potential during the process. The image is formed, thereby forming a negative static ft latent image corresponding to the original on the surface of the organic photoreceptor.

In the transfer step, an electrostatic transfer method can be preferably used. Specifically, for example, a transfer device that generates AC corona discharge is placed so as to face the organic photoreceptor through the transfer material, and AC corona discharge is applied to the transfer material from the back side of the organic photoreceptor. The toner carried on the surface of the transfer material is transferred to the surface of the transfer material.

In the cleaning step, a cleaning blade is used. This cleaning blade is preferably made of urethane rubber, for example, and in this case, cleaning performance and durability are improved. The cleaning blade is usually placed in a state in which it is lightly and elastically pressed against the surface of the photoreceptor, and cleaning is accomplished by scraping off toner remaining on the surface of the photoreceptor.

In order to facilitate cleaning, it is preferable to add a static elimination process to neutralize the surface of the photoreceptor before this cleaning process. This static elimination step can be performed, for example, using a static eliminator that generates AC corona discharge.

In the fixing step, fixing is performed by a contact heating method using a heat roller fixing device having a heat roller coated with a fluororesin or a silicone resin. A heat roller fixing device usually includes a heat roller, a backup roller disposed in opposition to the heat roller, and a heating source for heating the heat roller, or a cleaning roller is further disposed in opposition to the heat roller. configured. Specifically, as a heat roller, a coating layer made of a fluororesin such as Teflon (polytetrafluoroethylene manufactured by DuPont) or a silicone resin is provided on the surface of a core material made of metal such as iron or aluminum. It is preferable to use a configuration configured as follows.

Further, as the backup roller, one constructed by providing a coating layer made of silicone rubber or the like on the surface of a metal core material can be preferably used.

FIG. 2 is an explanatory diagram showing an example of an image forming apparatus that can be suitably used to carry out the image forming method of the present invention.

Reference numeral 30 denotes a cabinet, and at the top of the cabinet 30, a glass original R placing stand 32 for placing an original 31 and a platen cover 33 for covering the original 31 are provided. A paper feed tray 41 into which transfer paper 40 is placed is provided at one end of the cabinet 30, and a paper discharge tray 42 is provided at the other end. 43 and 44 are paper feed rollers, and 45 is a paper discharge roller.

50 is an organic photoreceptor for forming a negative electrostatic latent image, and this organic photoreceptor 50 has a rotating drum shape. Around this organic photoreceptor 50, from the upstream side to the downstream side in the rotational direction, a corona charger 51, an exposure optical system 52, a magnetic blank developer 53, and an electrostatic transfer device 54 are arranged.
, a separator 55, and a blade type cleaning device 56 are arranged.

The exposure optical system 52 includes a first mirror unit 63 consisting of a light source 61 and a first mirror 62, and a pair of mirrors arranged in order along the optical path from the first mirror unit 63 to the optical body 50. The second mirror unit 64
, a lens 65 , a mirror 66 , and a dichroic mirror 67 . The first mirror unit 63 is movably provided below the document placing table 32 so as to be scanned with respect to the document placing table 32, and the second mirror unit 64 is arranged to move the document from the document scanning point to the illuminating light body 50. It is provided movably in accordance with the moving speed of the first mirror uni-nod 63 so as to keep the optical path length constant. When the original 31 placed on the original stand 32 is illuminated with slit-shaped illumination light scanned by the exposure optical system 52, slit-shaped reflected light images of the original &% 31 are sequentially formed by scanning. are sequentially projected onto the developing surface of the organic photoreceptor 50 which is rotated.

Is 70 a contact heating type heat roller constant? The roller fixing device RJ2H70 includes a heat roller 71 in which a heater 73 is disposed, and a backup roller 72 disposed in contact with the heat roller 7I.

In the above apparatus, the surface to be developed of the organic photoreceptor 50 is charged to a uniform negative potential by the corona charger 51, and then imagewise exposed by the exposure optical system 52, so that the surface of the organic photoreceptor 50 is
A negative electrostatic latent image corresponding to the original image is formed on the surface to be developed. This negative electrostatic latent image is developed by the magnetic plan developer 53 to form a toner image corresponding to the original image.

The toner image on the organic photoreceptor 50 is electrostatically transferred onto the transfer paper 40 by the electrostatic transfer device 54, and the toner image on the transfer paper 40 is heated and fixed by the heat roller fixing device 70 to form a fixed image. On the other hand, the surface of the organic photoreceptor 50 that has passed through the electrostatic transfer device 54 is rubbed by a blade-type cleaning device 56, and the toner remaining on the surface is scraped off, resulting in the original clean surface. In addition to that,
It will be subjected to the charging process by the corona charger 51 again.

[Specific examples]

Hereinafter, specific examples and comparative examples of the present invention will be described, but the present invention is not limited to these examples.

(Manufacture of inorganic fine particles) (1) Inorganic fine particles A (for the present invention) rX-2, which is a silicone oil having an epoxy group
A first treatment liquid was prepared by dissolving 2-342J (manufactured by Shin-Etsu Chemical Co., Ltd.) in 80 parts of hexane.

Next, 100 parts by weight of silica fine particles "Aerosil 200j (manufactured by Nippon Aerosil Co., Ltd.)" was placed in a mixer, and while rotating, 100 parts of heavy oil of the above-mentioned first treatment liquid was gradually added dropwise to it, and after the dropping was completed, These were placed in a flask and heated and dried for 1 hour while being scooped 1↑, thereby obtaining inorganic fine particles whose surfaces were treated with silicone oil having an epoxy group.

And the amino compound hexamethylene diamine 2
A second treatment liquid was prepared by dissolving 0 parts by weight in 80 parts by weight of hexane.

100 parts by weight of inorganic fine particles whose surface was treated with the silicone oil having an epoxy group were treated in the same manner as above using 100 parts by weight of the second treatment liquid, and the surface was further treated with an amino compound. Inorganic fine particles were obtained. This will be referred to as "inorganic fine particles A." The inorganic fine particles A have an average primary particle diameter of 12 mp, BET
The specific surface area determined by the method was 9 (1 m''/g).

(2) Inorganic fine particles B (for the present invention) rSF- which is a silicone oil having an epoxy group
8411J (manufactured by Le Silicone Co., Ltd.) was dissolved in 85 parts by weight of toluene to prepare a first treatment liquid.

Next, the same process as in the production of inorganic fine particles A was carried out except that 100 parts by weight of this first treatment liquid was used to obtain inorganic fine particles whose surfaces were treated with silicone oil having an epoxy group.

And the amino compound diethylenetriamine 1O
Parts by weight were dissolved in 90 parts by weight of hexane to prepare one round of the second treatment tube.

100 parts by weight of inorganic fine particles whose surface had been treated with the silicone oil containing an epoxy group were treated in the same manner as above using 1100 parts by weight of the second treatment, and the surface was further treated with an amino compound. Nothing
A Hui particles were obtained. These are referred to as "inorganic fine particles B". The inorganic fine particles B had an average primary particle diameter of 7 u and a specific surface area of 122 ffi''/g by the BET method.

(3) Inorganic fine particles C (for the present invention) rS, which is a silicone oil having an epoxy group
F-8413J (manufactured by Torre Silicone Co., Ltd.> 1
A first treatment liquid was prepared by dissolving 0 parts by weight in 90 parts by weight of toluene.

Next, a silicone containing epoxy group was processed in the same manner as in the production of inorganic fine particles A, except that 100 parts by weight of the first treatment liquid and 100 parts by weight of silica fine particles "Aerosil 300J (manufactured by Nippon Aerosil Co., Ltd.) were used." Inorganic fine particles whose surfaces were treated with oil were obtained.

And the amine compound triethylenetetramine 1
A second treatment liquid was prepared by dissolving 5 parts by weight in 85 parts by weight of hexane.

100 parts by weight of inorganic fine particles whose surface was treated with the above-mentioned epoxy group-containing noricorn oil were added to the above-mentioned second treatment 1.
′! Using 100 parts by weight of l'm, treatment was performed in the same manner as above to obtain inorganic fine particles whose surfaces were further treated with an amino compound. This will be referred to as "inorganic fine particles C." The inorganic fine particles C have an average primary particle diameter of 13u,
The specific surface area determined by the BET method was 72 m''/g.

(4) Inorganic fine particles D (for comparison) Silica fine particles "Aerosil 200" (manufactured by Nippon Aerosil Co., Ltd.) were placed in a closed Henschel mixer heated to 100°C, and the silica fine particles were mixed with amino group-containing silicone oil using isopropyl alcohol. The solution (viscosity 1200 cps, amino acid 93500) was stirred at high speed while spraying at a rate such that the amount of silicone oil treated was 2.0% by weight, and then Comparative inorganic fine particles were obtained which were dried at a temperature of 150° C. and whose surfaces were treated with an amine group-containing silicone oil. These are referred to as "inorganic fine particles D."

(5) Inorganic fine particles E (for comparison) Silica fine particles [Aerosil 200J (manufactured by Nippon Aerosil Co., Ltd.) were placed in a closed Henschel mixer heated to 70°C, and an amino group-containing silane coupling agent was added to the silica fine particles. A solution of γ-aminopropyltriethquinone dissolved in alcohol was stirred at high speed while being sprayed at a rate such that the treatment amount of the amino group-containing silane coupling agent was 5.0%, and then the temperature was increased. Comparative inorganic fine particles were obtained which were dried at 120° C. and whose surfaces were treated with an amino group-containing silane coupling agent.

These are referred to as "inorganic fine particles E."

<Example 1> (1) Toner! ! ! 100 parts by weight of polystyrene-n-butyl acrylate copolymer (copolymerization weight ratio -82:18) and 10 parts by weight of carbon black [Mogul LJ (manufactured by Cabosoto)]
The overlapping portion and 2 parts by weight of the metal-containing dye were mixed in a type B blender, then melted and kneaded with two rolls, cooled, coarsely ground with a hammer mill, further finely ground with a jet mill, and then The toner was classified using an air classifier to obtain a non-magnetic toner having an average particle size of 11.0 μ3. This is referred to as "toner l".

(2) Manufacture of developer Add 50 parts by weight of the above-mentioned toner 1 to 0.00 parts by weight of the above-mentioned inorganic fine particles A.
By adding 5 parts by weight and mixing these with a Henschel mixer, inorganic fine particles are attached to or implanted into the surface of the toner particles to hold them, and a carrier made of iron powder rDSP 138j (manufactured by Nippon Tetsuko Kogyo Co., Ltd.) is further added to these particles. 950 parts by weight of the above were mixed to obtain an electrostatic image developer of the present invention which is a two-component developer. This is referred to as "developer l".

(3) Live-action test 0 test l (Gift test under room temperature environmental conditions) An organic photoreceptor for forming a negative electrostatic latent image, a contact type magnetic brush developer, and an AC corona Tll electric current. A corona transfer device, a heat roller with a diameter of 30φ whose surface layer is made of Teflon (polytetrafluoroethylene manufactured by DuPont), and a surface layer made of noricorn rubber rKE-1300R
T■J (Electrophotographic copying ar U - comprising a heat roller fixing device made of a backup roller formed by I3 Koshi Kagaku Kogyo Co., Ltd. 58 and a cleaning device having a cleaning blade made of urethane rubber) B
ix 1550~IR'' (manufactured by Konishi Roku Photo Industry Co., Ltd.), the above developer 1 was used to continuously copy images 30,000 times under room temperature environmental conditions of 20°C and 60% relative humidity. A live-action test was conducted to evaluate the following items. The results are shown in Table 2 below.

The above-mentioned organic photoreceptor has a negatively charged two-layer photosensitive layer formed using an anthrone pigment as a carrier-generating substance and a carbadul derivative as a carrier-transporting substance, and a rotating drum-shaped aluminum conductive layer. It is constructed by laminating layers on a support.

The surface potential (highest potential) of the organic photoreceptor during charging is -700V, the gap (Dsd) between the photoreceptor and the developing sleeve in the developing space is 0.911no, and the distance between the tip of the regulation plate and the developing sleeve. (Hcu L) was 0.6 mm, the magnet body was a fixed type, the magnetic flux density on the surface of the developing sleeve was 800 Gauss, and the bias voltage applied to the developing sleeve was -100 V in DC voltage.

■Fog “Sakura Densitometer” (manufactured by Konishiroku Photo Industry Co., Ltd.)
The determination was made by measuring the relative density of the white background portion of the original 1 with a degree of 0.0 to the copied image. Note that the white background reflection density was set to 0.0. In the evaluation, when the relative concentration was less than 0.01, it was evaluated as "○j", when it was 0.01 or more and less than 0.03, it was evaluated as "Δ", and when it was 0.03 or more, it was evaluated as "x".

■Image density "Sakura densitometer" (manufactured by Konishiroku Photo Industry Co., Ltd.)
The relative l degree of a white background area with an original density of 0.0 to a copied image was measured using the following.

(2) Image Quality Copied images were visually judged from three points: image blanking, image unevenness, and sharpness. The evaluation was ``x'' if it was poor and had a practical problem, ``△'' if it was slightly defective but at a practical level, and rOJ if it was good.

■Toner scattering Visually observe the inside of the copying machine and the copied image. If the toner scattering is almost not observed and it is in good condition, 1-0", and if there is some toner scattering but it is at a practical level, "1-0" is the case.
△", and cases where a lot of toner scattering was observed and there was a problem in practical use were rated "x".

(2) Cleaning Properties After repeatedly forming images, the surface of the organic photoreceptor was visually observed immediately after being cleaned with a cleaning blade, and judgment was made based on the presence or absence of deposits on the surface of the organic photoreceptor. The evaluation is ``○-1'' when there is almost no deposits observed and the product is in good condition, and ``△'' when there are some deposits but it is at a practical level. Let the case be xj.

(2) Durability of the fixing device Judgment was made based on the occurrence of an offset phenomenon, the occurrence of paper jams, and the back surface lη of the transfer paper caused by dirt on the heat roller and Vanoqua 7 propeller that constitute the fixing device. The evaluation was ``x'' if it was poor and had a practical problem, ``△'' if it was slightly defective but at a practical level, and ``○'' if it was good.

Q Test 2 (Photograph test under high temperature environmental conditions) A photo test was conducted in the same manner except that the environmental conditions were a high temperature environment of 30° C. and 80% relative humidity, and each of the above items was evaluated. The results are shown in Table 3 below.

<Example 2> A developer was obtained in the same manner as in Example 1, except that 0.4 parts by weight of inorganic fine particles B was used instead of inorganic fine particles A.

This will be referred to as "Developer 2".

A photographic test was carried out in the same manner as in Example 1, except that this developer 2 was used, and evaluations were made in the same manner. The results are shown in the second section below.
Shown in Table and Table 3.

<Example 3> A developer was obtained in the same manner as in Example 1, except that in the production of the developer in Example 1, a 0.6-type needle of inorganic fine particles C was used instead of inorganic fine particles A. .

This will be referred to as "Developer 3".

A photographic test was carried out in the same manner as in Example 1, except that this developer 3 was used, and evaluations were made in the same manner. The results are shown in the second section below.
Shown in Table and Table 3.

<Comparative Example 1> In producing the developer of Example 1, the developer was produced in the same manner as in Example 1, except that 0.4 parts of comparative inorganic fine particles were used instead of inorganic fine particles. Obtained. This is referred to as "comparative developer 1."

A photographic test was carried out in the same manner as in Example 1, except that this comparative developer 1 was used, and evaluations were made in the same manner.

The results are shown in Tables 2 and 3 below.

<Comparative Example 2> A developer was produced in the same manner as in Example 1, except that 0.4 weight Y part of comparative inorganic fine particles E was used instead of inorganic fine particles A in producing the developer of Example 1. 1). this[
It is referred to as comparative developer 2j.

A photographic test was carried out in the same manner as in Example 1, except that this comparative developer 2 was used, and evaluations were made in the same manner.

The results are shown in Tables 2 and 3 below.

As can be understood from the results in Tables 2 and 3,
According to the developers 1 to 3 of the present invention, the Pj triboelectricity and fluidity of the toner are good. The image can be developed well without toner scattering, and in the transfer process, it can be transferred at a high transfer rate by electrostatic transfer means.In the cleaning process, the cleaning process has a simple structure. The blade can perform good cleaning, and in the fixing process, the heat roller fixing device can perform good fixing without causing offset phenomenon.As a result, the image is clear with no fogging, missing images, or uneven images. It is possible to form a good image with high image quality and high image density.

Even when performing image forming processes many times, the track roller and backup roller in the heat roller fixing device do not run out, and the service life of the roller is significantly extended, and even under high temperature environmental conditions. Good images can be stably formed.

On the other hand, according to Comparative Developer 1, since the comparative inorganic fine particles whose surface was treated with amino group-containing silicone oil were used, the triboelectric charging properties of the toner were inferior.
As a result, an unclear image with a lot of fog and low image density is obtained. Furthermore, when the image forming process is performed many times, the blur of the image gradually increases, resulting in a defective image at an early stage.

In addition, according to Comparative Developer 2, since comparative inorganic fine particles E whose surfaces were treated with an amino group-containing silane coupling agent were used, the surface of the inorganic fine particles was completely treated with the amino group-containing silane coupling agent. Therefore, negatively charged sites and hydrophilic sites of the fine particles remain, resulting in poor triboelectric charging properties of the toner, resulting in a blurred image with a lot of fog and low image density. . In addition, triboelectric charging properties become unstable due to the influence of humidity, and as a result, fogging occurs significantly under high-temperature environmental conditions, and the image 74 degrees decreases to 50 degrees, making the image significantly blurred. Become.

Furthermore, when we conducted a continuous photographing test over 50,000 times using the developers 1 to 3 according to the present invention and the developing method according to the present invention, good results similar to those shown in Tables 2 and 3 were obtained. Obtained.

In addition, when we conducted a continuous photographing test over 70,000 times using the developers 1 to 3 according to the present invention and applying the image forming method according to the present invention, the same good results as shown in Tables 2 and 3 were obtained. was gotten.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an example of an electrostatic image developing apparatus that can be suitably used to carry out the electrostatic image developing method of the present invention, and FIG. FIG. 2 is an explanatory diagram showing an example of an image forming apparatus that can be suitably used. DESCRIPTION OF SYMBOLS 10... Organic photoreceptor 10A... Conductive support 10B... Photosensitive layer 11... Developing sleeve 12... Magnet body 13... Regulating blade 23... Developer N (magnetic plan) 24...Development space 30...Cabinet 31...Original! 332... Original table 40... Transfer paper 50... Organic photoreceptor 51... Corona charger 52... Exposure optical system 53... Magnetic brush developer 54... Electrostatic transfer device 56... Blade type cleaning device 70... Heat roller fixing device

Claims (1)

[Scope of Claims] 1) An electrostatic image developer characterized in that the surface thereof is treated with a silicone oil having an epoxy group and further contains inorganic fine particles treated with an amino compound. 2) The electrostatic image developer according to claim 1, wherein the inorganic fine particles are made of silica. 3) A negative electrostatic latent image formed on the surface of a photoreceptor made of an organic photoconductive semiconductor is treated with a compound having an epoxy group on the surface, and further contains inorganic fine particles treated with an amino compound. An electrostatic image developing method characterized by developing with an electrostatic image developer comprising: 4) A latent image forming step of forming a negative electrostatic latent image on the surface of a photoreceptor made of an organic photoconductive semiconductor; , a development step of developing with an electrostatic image developer containing inorganic fine particles treated with an amino compound, a transfer step of electrostatically transferring the toner image obtained by the development to a transfer material, and a post-transfer step. a cleaning step of cleaning the developer remaining on the surface of the photoreceptor with a cleaning blade; and a heating roller fixing device having a heating roller coated with a fluororesin or silicone resin to remove the developer remaining on the surface of the transfer material. An image forming method comprising: a fixing step of heating and fixing a toner image.