JP2003122039A - Image forming device and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device and an image forming method, which do not generate any defective image such as a black dot, etc., by improving the toner cleaning performance of a cleaning device for cleaning toner while applying a bias voltage and coming into contact with a photoreceptor, and also, resolving the problem of an image memory easily occurring in the case of using the cleaning device. SOLUTION: The device is provided with the photoreceptor and a cleaning means, and the cleaning means is provided with a cleaning blade and a cleaning roller on which a bias voltage whose polarity is reverse to that of the electrified toner polarity is applied, and the photoreceptor is provided with an intermediate layer arranged between a conductive supporting body and a photoreceptor layer, and the photoreceptor is characterized in that it is an organic photoreceptor having the intermediate layer including at least binder resin and N type semiconductor particulates obtained by performing a surface treatment several times, besides, the final surface treatment is performed by using reactive organic silicon compound.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus and an image forming method for forming an image on a recording material by an electrophotographic method, and more particularly to improvement of a photoconductor cleaning technique.

[0002]

2. Description of the Related Art In recent years, in electrophotographic image forming apparatuses, the particle size of toner has been reduced from the viewpoint of high image quality. By using a toner with a small particle size, high resolution can be achieved by improving resolution and fine gradation expression. The problem of occurs. One of the problems in cleaning is the problem that the toner has a smaller particle size and the adhesion of the toner to the photoconductor is apparently increased, which makes cleaning difficult. In particular, the toner produced by the granulation polymerization method, which is an effective method for producing a small particle size toner, has a small particle size and particles that are close to a spherical shape. In the cleaning process for cleaning the body, there is a strong tendency for toner to pass through between the photoconductor and the edge of the cleaning blade, so-called “sleeping”, resulting in poor cleaning.

As a countermeasure against such a cleaning failure, Japanese Patent Laid-Open No. 3-189675 proposes a cleaning method in which an electrostatic toner removing action is added to a mechanical toner removing action by a cleaning blade. In the cleaning method disclosed in the above-mentioned publication, a brush roller to which a bias voltage is applied is provided on the upstream side of the cleaning blade.

Further, as a cleaning method improved from the method disclosed in Japanese Patent Laid-Open No. 3-189675, Japanese Patent Application No. 11-2
No. 72003 proposes a cleaning method in which a cleaning roller to which a voltage is applied is arranged on the upstream side of the cleaning blade.

However, when these methods are used, there is a problem that an image memory is likely to be generated by applying a bias voltage to the surface of the photoconductor. That is, when a bias charge is applied by contact with the surface of the photoconductor, the charge is injected from the cleaning roller to the photoconductor, and this charge cannot be sufficiently erased by subsequent pre-exposure exposure, etc., and remains in an image form. A so-called image memory often appears as an afterimage on the screen. Such an image memory is likely to occur when an organic photoconductor using a phthalocyanine-based pigment or a perylene-based pigment having high sensitivity to long-wavelength light is adopted as the photoconductor.

As described above, the cleaning method using the cleaning roller to which the bias voltage is applied has a secondary effect, and when applied to the image forming apparatus using the conventional organic photoconductor, a good image is obtained. Was difficult to obtain.

In recent years, with the computerization of offices and computerization, as an image forming method by electrophotography,
An image forming method for forming a digital image on an electrophotographic photosensitive member by writing by digital signal processing has become mainstream.

In this digital image formation, as an electrophotographic photosensitive member, reversal is most suitable for developing a digital latent image as well as electrophotographic characteristics such as good charging characteristics and sensitivity and low dark decay. Appropriateness for development is required.

However, in this reversal development,
The problem that minute defects at the unexposed potential are enlarged and black spot-like image defects are likely to occur has not yet been sufficiently solved.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art as described above, and to use a cleaning device that applies a bias voltage and contacts a photoconductor to clean the toner. It is an object of the present invention to provide an image forming apparatus and an image forming method which improve the cleaning property, solve an image memory that is likely to occur when the cleaning apparatus is used, and at the same time, do not cause image defects such as black spots.

[0011]

The above-mentioned objects of the present invention are as follows.
It is achieved by any of the following inventions.

1. Photoreceptor, latent image forming means for forming an electrostatic latent image on the photoreceptor, developing means for developing the electrostatic latent image on the photoreceptor to form a toner image on the photoreceptor, on the photoreceptor In an image forming apparatus having a transfer unit that transfers a toner image to a recording material and a cleaning unit that cleans the photosensitive member after the transfer, the cleaning unit is a conductive or semiconductive elastic member that contacts the surface of the photosensitive member. A cleaning roller having a body, a cleaning blade disposed downstream of the cleaning roller in the moving direction of the photoconductor, and in contact with the surface of the photoconductor, and contributing to toner image formation in the development by the developing means. The toner is removed from the cleaning roller and a constant current power source that applies a bias voltage having a polarity opposite to the charging polarity of the toner to the cleaning roller. It has a removal means,
The photoreceptor has an intermediate layer between a conductive support and a photosensitive layer, the intermediate layer is subjected to at least a binder resin and a plurality of surface treatments, and the final surface treatment uses a reactive organosilicon compound. An image forming apparatus characterized by being an organic photoconductor containing N-type semiconductive fine particles.

2. Photoreceptor, latent image forming means for forming an electrostatic latent image on the photoreceptor, developing means for developing the electrostatic latent image on the photoreceptor to form a toner image on the photoreceptor, on the photoreceptor In an image forming apparatus having a transfer unit that transfers a toner image to a recording material and a cleaning unit that cleans the photosensitive member after the transfer, the cleaning unit is a conductive or semiconductive elastic member that contacts the surface of the photosensitive member. A cleaning roller having a body, a cleaning blade disposed downstream of the cleaning roller in the moving direction of the photoconductor, and in contact with the surface of the photoconductor, and contributing to toner image formation in the development by the developing means. The toner is removed from the cleaning roller and a constant current power source that applies a bias voltage having a polarity opposite to the charging polarity of the toner to the cleaning roller. It has a removal means,
The photoreceptor has an intermediate layer between a conductive support and a photosensitive layer, the intermediate layer is subjected to at least a binder resin and a plurality of times of surface treatment, and the final surface treatment uses a reactive organotitanium compound. An image forming apparatus characterized by being an organic photoconductor containing N-type semiconductive fine particles.

3. Photoreceptor, latent image forming means for forming an electrostatic latent image on the photoreceptor, developing means for developing the electrostatic latent image on the photoreceptor to form a toner image on the photoreceptor, on the photoreceptor In an image forming apparatus having a transfer unit that transfers a toner image to a recording material and a cleaning unit that cleans the photosensitive member after the transfer, the cleaning unit is a conductive or semiconductive elastic member that contacts the surface of the photosensitive member. A cleaning roller having a body, a cleaning blade disposed downstream of the cleaning roller in the moving direction of the photoconductor, and in contact with the surface of the photoconductor, and contributing to toner image formation in the development by the developing means. The toner is removed from the cleaning roller and a constant current power source that applies a bias voltage having a polarity opposite to the charging polarity of the toner to the cleaning roller. It has a removal means,
The photoreceptor has an intermediate layer between a conductive support and a photosensitive layer, the intermediate layer is subjected to at least a binder resin and a plurality of surface treatments, and the final surface treatment uses a reactive organozirconium compound. An image forming apparatus characterized by being an organic photoconductor containing N-type semiconductive fine particles.

4. Photoreceptor, latent image forming means for forming an electrostatic latent image on the photoreceptor, developing means for developing the electrostatic latent image on the photoreceptor to form a toner image on the photoreceptor, on the photoreceptor In an image forming apparatus having a transfer unit that transfers a toner image to a recording material and a cleaning unit that cleans the photosensitive member after the transfer, the cleaning unit is a conductive or semiconductive elastic member that contacts the surface of the photosensitive member. A cleaning roller having a body, a cleaning blade disposed downstream of the cleaning roller in the moving direction of the photoconductor, and in contact with the surface of the photoconductor, and contributing to toner image formation in the development by the developing means. The toner is removed from the cleaning roller and a constant current power source that applies a bias voltage having a polarity opposite to the charging polarity of the toner to the cleaning roller. It has a removal means,
An organic photoreceptor in which the photoreceptor has an intermediate layer between a conductive support and a photosensitive layer, and the intermediate layer contains at least a binder resin and N-type semiconductive fine particles which have been subjected to a hydrophobic surface treatment. An image forming apparatus characterized in that there is.

5. 5. The image forming apparatus as described in 4 above, wherein the N-type semiconductive fine particles subjected to the hydrophobic surface treatment are titanium oxide particles surface-treated with a reactive organic silicon compound having a fluorine atom.

6. 6. The image forming apparatus according to any one of 1 to 5 above, wherein the constant current power source outputs a constant current of 1 μA to 50 μA.

7. The cleaning roller is 10 ² Ω
7. The image forming apparatus described in any one of 1 to 6 above, which has a surface resistivity of 10 to 10 ¹⁰ Ω.

8. 8. The image forming apparatus according to any one of 1 to 7 above, wherein the cleaning roller is made of an elastic body.

9. 9. The image forming apparatus according to any one of 1 to 8 above, wherein the cleaning roller is made of a foam material and a resin film covering the foam material.

10. 10. The image forming apparatus according to any one of 1 to 9 above, further comprising a recycling unit that supplies the toner collected by the cleaning unit to the developing unit and reuses the toner.

11. 11. The image forming apparatus according to any one of 1 to 10 above, wherein the removing unit is a blade.

12. 12. The image forming apparatus described in any one of 1 to 11 above, wherein a plurality of the removing means are provided.

13. 13. The image forming apparatus described in any one of 1 to 12 above, wherein the photoconductor has a surface layer containing a siloxane resin having a crosslinked structure.

14. 14. The image forming apparatus according to any one of 1 to 13 above, wherein the photoconductor has a surface layer containing a siloxane-based resin having a structural unit having a charge transporting property.

15. The photoreceptor has a conductive support, an intermediate layer, a photosensitive layer, and a surface layer containing a siloxane-based resin having a crosslinked structure, and has a structure in which the above layers are laminated in the above order. 15. The image forming apparatus according to any one of 1 to 14 above.

16. The cleaning blade is 0.
16. The image forming apparatus as described in any one of 1 to 15 above, wherein cleaning is performed by contacting the photoconductor by a counter method with a weight of 1 N / m to 30 N / m.

17. The cleaning blade is 0 °
The cleaning method is carried out by contacting the photosensitive member by a counter method at a contact angle θ of -40 °.
The image forming apparatus according to any one of items 1 to 16.

18. The cleaning blade is 20
18. The image forming apparatus described in any one of 1 to 17 above, which is made of an elastic body having a hardness within a range of 90 ° to 90 °.

19. The developing means has a volume average particle diameter of 3
19. The image forming apparatus according to any one of 1 to 18 above, wherein the image forming apparatus develops using a toner having a size of from μm to 8.5 μm.

20. 20. An image forming method using the image forming apparatus according to any one of 1 to 19 above.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to specific embodiments.

Image Forming Apparatus FIG. 1 shows an image forming apparatus according to an embodiment of the present invention.
In the figure, 1 is a photoconductor.

As the photoconductor 1, an organic photoconductor having a photoconductive layer in which an organic photoconductor is dispersed in a resin is preferable from the viewpoints of environment and cost, and as will be described later, cleaning of the cleaning means 8 for a long period of time. A photoreceptor is used so that the performance is maintained.

The photosensitive member 1 is not limited to the drum-shaped photosensitive member shown in the figure, but may be a belt-shaped photosensitive member.
Reference numeral 2 denotes a charging unit that charges the photoconductor 1 and forms a uniform potential on the photoconductor 1. As the charging means, a scorotron charger having a control grid and a discharge electrode or a contact charging type charger using a roller to which a voltage is applied is preferable.

Reference numeral 3 is an exposing means for exposing the photosensitive member 1.
As the exposure means, a scanning exposure device having a laser diode as a light source and a scanning optical system including a polygon mirror, a lens and a mirror, and a scanning optical device having a light emitting diode array and an image forming optical fiber are preferable. The exposure unit 3 performs dot exposure on the photoconductor 1 according to the image data.

A developing means 4 contains a one-component developer or a two-component developer, and the developer is conveyed to a developing area by a developing sleeve 41 as a developer conveying means so that the electrostatic latent image on the photosensitive member 1 is conveyed. The image is developed to form a toner image on the photoconductor 1. To the developing sleeve 41, a DC developing bias having the same polarity as the charging polarity of the charging unit 2 or a developing bias in which a DC voltage having the same polarity as the charging polarity of the charging unit 2 is superimposed on an AC voltage is applied, and exposure by the exposing unit 3 is performed. Reversal development is performed in which toner is attached to the portions. The developing means 4 is not limited to reversal development. It is of course possible to use a developing unit that performs regular development using toner charged to the opposite polarity to the electrostatic latent image.

Reference numeral 5 is a transfer means composed of a corona charger. The transfer unit 5 charges the recording paper P with a polarity opposite to that of the toner on the photoconductor 1 to transfer the toner image to the recording paper P.

Reference numeral 6 denotes a separating means composed of a corona charger, which performs AC corona charging on the recording paper P to neutralize the recording paper P and separate it from the photoconductor 1.

A fixing unit 7 fixes the toner image on the recording paper P by a heating roller 71 containing a heat source such as a halogen lamp and a pressure roller 72 in pressure contact with the heating roller 71.

Reference numeral 8 is a cleaning means. Untransferred toner and untransferred toner are attached to the photoconductor 1 after the transfer, and the photoconductor 1 needs to be cleaned in order to perform the next image formation. The cleaning means 8 is a cleaning blade 8 made of an elastic blade such as urethane rubber.
1 and a cleaning roller 82. The cleaning blade 81 is supported by a fixed blade holder 83, and the tip edge of the cleaning blade 81 is pressed against the photoconductor 1 at a substantially constant pressure due to the elasticity of the blade. As the blade holder 83, it is also possible to use a blade holder that is rotatable about an axis and that applies a constant pressure contact force to the cleaning blade 81 by applying a spring or gravity. The tip of the cleaning blade 81 contacts the photoreceptor 1 in a counter manner so that the tip and the surface of the photoreceptor 1 form an acute angle θ on the cleaned side.

Reference numeral 9 denotes a recycling means, which conveys the toner collected by the cleaning blade 81 and the cleaning roller 82 to the developing means 4 and throws it into the developing means 4 for reuse.

A bias voltage is applied to the cleaning roller 82 by a constant current power source 84 to electrostatically attract the toner on the photoconductor 1 to the cleaning roller 82. The polarity of the bias voltage contributes to the development in the developing means 4 and is opposite to the polarity of the toner forming the toner image. As shown in FIG. 2, a scraper 89 as a removing unit contacts the cleaning roller 82 by a counter method to remove the toner collected from the photoconductor 1 and attached to the cleaning roller 82.

The main configuration in the next embodiment will be described. Photoreceptor First, the photoreceptor 1 of FIG. 1 (hereinafter referred to as the present photoreceptor) used in the embodiment of the present invention will be described in detail.

The organic photoreceptor of the present invention is characterized in that the intermediate layer provided between the conductive support and the photosensitive layer contains N-type semiconductive fine particles which have been subjected to a specific hydrophobic surface treatment, and a binder resin. I am trying. The hydrophobic surface treatment is a surface treatment for coating a hydrophilic group such as a hydroxyl group existing on the surface of the N-type semiconductive fine particles, and the coating may be a physical coating or a chemical coating. The surface treatment of the N-type semiconductive fine particles is characterized in that the surface treatment is performed plural times, and the last surface treatment among the plural times of surface treatment is a surface treatment with a reactive organosilicon compound. Characterized in that the surface treatment is carried out a plurality of times, and the last surface treatment among the plurality of surface treatments is a surface treatment with a reactive organotitanium compound. And characterized in that the final surface treatment of the plurality of times of surface treatment is a surface treatment with a reactive organozirconium compound, characterized in that it is a surface treatment with a reactive organosilicon compound having a fluorine atom There is.

A bias voltage is applied to the cleaning roller by providing an intermediate layer between the conductive support and the photosensitive layer by containing N-type semiconductive fine particles subjected to surface treatment of any one of these four. Even if the voltage is applied, the occurrence of memory can be prevented, and good cleaning properties can be achieved.

Further, in the present invention, it has been found that it is particularly preferable to use titanium oxide fine particles as the N-type semiconductive fine particles.

The N-type semiconductive fine particles and titanium oxide used in the present invention will be described in detail below with respect to the surface treatment.

The N-type semiconductive fine particles used in the present invention are fine particles having the property of using electrons as conductive carriers. That is, the property that the conductive carrier is an electron is
It is considered that by incorporating the N-type semiconductor fine particles in an insulating binder, hole injection from the substrate is effectively blocked, and the N-type semiconductor fine particles do not exhibit blocking properties with respect to electrons from the photosensitive layer. .

Specific examples of the N-type semiconductive fine particles include fine particles of titanium oxide (TiO ₂ ), zinc oxide (ZnO), tin oxide (SnO ₂ ), etc.
Particularly, titanium oxide is preferably used.

The N-type semiconductive fine particles used in the present invention have an average particle size of 10 nm or more and 200 or more in number average primary particle size.
It is preferably in the range of nm or less, more preferably 10
nm to 100 nm, particularly preferably 15 nm to 50 n
m.

The number average primary particle diameter is within the above range N
The intermediate layer using the type semiconductive fine particles can have a fine dispersion in the layer, and has sufficient potential stability and a function of preventing the occurrence of image memory such as black spots.

The number average primary particle size of the N-type semiconductive fine particles, for example, in the case of titanium oxide, is enlarged 10,000 times by observation with a transmission electron microscope, and 100 particles are randomly observed as primary particles to obtain an image. It is a measured value as an average diameter in the Feret direction by analysis.

The N-type semiconductive fine particles used in the present invention may have a dendritic, needle-like, or granular shape, and the N-type semiconductive fine particles having such a shape are, for example, titanium oxide particles. As the crystal type, there are anatase type, rutile type, amorphous type, and the like, but any crystal type may be used, or two or more crystal types may be mixed and used. Among them, the rutile type is the best.

One of the surface treatments performed on the N-type semiconductive fine particles of the present invention is to carry out a plurality of surface treatments, and the final surface treatment is a reaction in the plurality of surface treatments. The surface treatment is performed with a crystalline organic silicon compound. Further, among the plurality of surface treatments, at least one surface treatment is performed using at least one compound selected from alumina, silica, and zirconia, and finally surface treatment with a reactive organosilicon compound. Is preferably performed.

Alumina treatment, silica treatment, and zirconia treatment mean that alumina, silica, and
Alternatively, it refers to a treatment for precipitating zirconia, and the alumina, silica, and zirconia deposited on these surfaces also include hydrates of alumina, silica, and zirconia. Further, the surface treatment of the reactive organic silicon compound means that the reactive organic silicon compound is used in the treatment liquid.

As another method of the surface treatment of the N-type semiconductive fine particles of the present invention, the surface treatment is performed a plurality of times, and the final surface treatment is performed in the plurality of surface treatments. The surface treatment is performed using a reactive organic titanium compound or a reactive organic zirconium compound. Further, among the plurality of surface treatments, at least one surface treatment is performed using at least one compound selected from alumina, silica, and zirconia as described above, and finally, a reactive organotitanium compound or It is preferable to perform surface treatment with a reactive organozirconium compound.

Thus, the surface treatment of the N-type semiconductive fine particles such as titanium oxide particles is performed at least twice, so that the surface of the N-type semiconductive fine particles is uniformly coated (treated), and the surface is treated. When the treated N-type semiconducting fine particles are used in the intermediate layer, the dispersibility of the N-type semiconducting fine particles such as titanium oxide particles in the intermediate layer is good, and image defects such as generation of image memory such as black spots occur. It is possible to obtain a good photoconductor that does not generate.

Further, the surface treatment is carried out a plurality of times by using alumina and silica, and then the surface treatment is carried out by a reactive organosilicon compound, or the surface treatment by using alumina and silica is followed by the reactive organic treatment. Those which are surface-treated with a titanium compound or a reactive organic zirconium compound are particularly preferable.

The treatment of alumina and silica described above may be carried out at the same time. In particular, the treatment of alumina is first carried out,
Next, it is preferable to perform silica treatment. Further, the treatment amount of alumina and silica when the treatment of alumina and silica is performed is preferably such that the amount of silica is larger than that of alumina.

The surface treatment of the N-type semiconductive fine particles such as titanium oxide with a metal oxide such as alumina, silica and zirconia can be performed by a wet method. For example, N-type semiconductive fine particles that have been surface-treated with silica or alumina can be produced as follows.

When titanium oxide particles are used as the N-type semiconductive fine particles, titanium oxide particles (number average primary particle diameter: 50) are used.
(nm) is dispersed in water at a concentration of 50 to 350 g / L to give an aqueous slurry, to which a water-soluble silicate or a water-soluble aluminum compound is added. After that, an alkali or an acid is added for neutralization to deposit silica or alumina on the surface of the titanium oxide particles. Subsequently, filtration, washing and drying are performed to obtain the target surface-treated titanium oxide. When sodium silicate is used as the water-soluble silicate, it can be neutralized with an acid such as sulfuric acid, nitric acid or hydrochloric acid.
On the other hand, when aluminum sulfate is used as the water-soluble aluminum compound, it can be neutralized with an alkali such as sodium hydroxide or potassium hydroxide.

The amount of the metal oxide used in the surface treatment is 0.1 to 100 parts by mass of N-type semiconductive fine particles such as titanium oxide particles in the charged amount during the surface treatment.
50 parts by weight, more preferably 1 to 10 parts by weight of metal oxide is used. Even when the above-mentioned alumina and silica are used, for example, in the case of titanium oxide particles, titanium oxide particles 1
It is preferable to use 1 to 10 parts by mass with respect to each 00 parts by mass, and it is preferable that the amount of silica is larger than that of alumina.

The surface treatment with the reactive organosilicon compound, which is performed after the surface treatment with the metal oxide, is preferably performed by the following wet method.

That is, the titanium oxide treated with the metal oxide is added to a solution prepared by dissolving or suspending the reactive organosilicon compound in an organic solvent or water, and the solution is stirred for a few minutes to 1 hour. To do. Then, in some cases, the liquid is subjected to a heat treatment, subjected to a process such as filtration and then dried to obtain titanium oxide particles whose surface is coated with an organosilicon compound. The reactive organic silicon compound may be added to a suspension of titanium oxide dispersed in an organic solvent or water.

In the present invention, the fact that the surface of titanium oxide particles is coated with a reactive organosilicon compound means
Photoelectron spectroscopy (ESCA), Auger electron spectroscopy (Au)
ger), secondary ion mass spectrometry (SIMS), and diffuse reflection FI-IR.

The amount of the reactive organic silicon compound used for the surface treatment is 0 with respect to 100 parts by mass of titanium oxide treated with the metal oxide in the charged amount at the time of the surface treatment. 1 to 50 parts by mass, more preferably 1 to 10 parts by mass. When the amount of surface treatment is less than the above range, the surface treatment effect is not sufficiently imparted, and the dispersibility of titanium oxide particles in the intermediate layer deteriorates.
Further, if it exceeds the above range, the electric performance is deteriorated, and as a result, the residual potential increases and the charging potential decreases.

Examples of the reactive organosilicon compound used in the present invention include compounds represented by the following general formula (2). Any compound that undergoes a condensation reaction with a reactive group such as a hydroxyl group on the surface of titanium oxide can be used. However, it is not limited to the following compounds.

Formula (2) (R) _n -Si- (X) _4-n (wherein Si represents a silicon atom, R represents an organic group in which carbon is directly bonded to the silicon atom, and X represents Represents a hydrolyzable group, and n represents an integer of 0 to 3.) In the organosilicon compound represented by the general formula (2), as the organic group in a form in which carbon is directly bonded to silicon represented by R, Alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, dodecyl, aryl groups such as phenyl, tolyl, naphthyl, biphenyl, γ-glycidoxypropyl, β- (3,4-epoxycyclohexyl) ethyl. Epoxy-containing groups such as γ-acryloxypropyl, γ-
(Meth) acryloyl group of methacryloxypropyl, hydroxyl group such as γ-hydroxypropyl, 2,3-dihydroxypropyloxypropyl, vinyl group such as vinyl and propenyl, mercapto group such as γ-mercaptopropyl, γ -Aminopropyl, N-β (aminoethyl) -γ-aminopropyl, and other amino-containing groups, γ-chloropropyl, 1,1,1-trifluoropropyl, nonafluorohexyl, perfluorooctylethyl, and other halogen-containing groups And other groups such as nitro and cyano-substituted alkyl groups. Examples of the hydrolyzable group for X include alkoxy groups such as methoxy and ethoxy, halogen groups, and acyloxy groups.

The organosilicon compound represented by the general formula (2) may be used alone or in combination of two or more kinds.

In the specific compound of the organosilicon compound represented by the general formula (2), when n is 2 or more, a plurality of R
May be the same or different. Similarly, when n is 2 or less, plural Xs may be the same or different. When two or more organosilicon compounds represented by the general formula (2) are used, R and X may be the same or different between the respective compounds.

The following compounds may be mentioned as examples of compounds in which n is 0. Tetrachlorosilane, diethoxydichlorosilane, tetramethoxysilane, phenoxytrichlorosilane, tetraacetoxysilane, tetraethoxysilane, tetraallyloxysilane, tetrapropoxysilane, tetraisopropoxysilane, tetrakis (2-methoxyethoxy) silane, tetrabutoxysilane , Tetraphenoxysilane, tetrakis (2-ethylbutoxy) silane, tetrakis (2-ethylhexyloxy) silane and the like.

Examples of the compound in which n is 1 include the following compounds. That is, trichlorosilane, methyltrichlorosilane, vinyltrichlorosilane, ethyltrichlorosilane, allyltrichlorosilane, n-propyltrichlorosilane, n-butyltrichlorosilane, chloromethyltriethoxysilane, methyltrimethoxysilane, mercaptomethyltrimethoxysilane, Trimethoxyvinylsilane, ethyltrimethoxysilane, 3,3,4
4,5,5,6,6,6-nonafluorohexyltrichlorosilane, phenyltrichlorosilane, 3,3,3-
Trifluoropropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, triethoxysilane, 3
-Mercaptopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 2-aminoethylaminomethyltrimethoxysilane, benzyltrichlorosilane, methyltriacetoxysilane, chloromethyltriethoxysilane, ethyltriacetoxysilane, phenyltrimethoxysilane, 3-allylthiopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-bromopropyltriethoxysilane, 3-allylaminopropyltrimethoxysilane, propyltriethoxysilane, hexyltrimethoxysilane, 3-aminopropyl Triethoxysilane, 3-methacryloxypropyltrimethoxysilane, bis (ethylmethylketoxime) methoxymethylsilane, pentyltriethoxysilane, octyl Triethoxysilane, a dodecyloxy triethoxy silane and the like.

Examples of the compound in which n is 2 include the following compounds. Dimethyldichlorosilane, dimethoxymethylsilane, dimethoxydimethylsilane, methyl-3,
3,3-trifluoropropyldichlorosilane, diethoxysilane, diethoxymethylsilane, dimethoxymethyl-3,3,3-trifluoropropylsilane, 3-chloropropyldimethoxymethylsilane, chloromethyldiethoxysilane, diethoxydimethyl Silane, dimethoxy-3-mercaptopropylmethylsilane, 3,3
4,4,5,5,6,6,6-nonafluorohexylmethyldichlorosilane, methylphenyldichlorosilane,
Diacetoxymethylvinylsilane, diethoxymethylvinylsilane, 3-methacryloxypropylmethyldichlorosilane, 3-aminopropyldiethoxymethylsilane, 3- (2-aminoethylaminopropyl) dimethoxymethylsilane, t-butylphenyldichlorosilane,
3-methacryloxypropyldimethoxymethylsilane,
3- (3-cyanopropylthiopropyl) dimethoxymethylsilane, 3- (2-acetoxyethylthiopropyl) dimethoxymethylsilane, dimethoxymethyl-2-
Piperidinoethylsilane, dibutoxydimethylsilane,
3-dimethylaminopropyldiethoxymethylsilane,
Examples include diethoxymethylphenylsilane, diethoxy-3-glycidoxypropylmethylsilane, 3- (3-acetoxypropylthio) propyldimethoxymethylsilane, dimethoxymethyl-3-piperidinopropylsilane, and diethoxymethyloctadecylsilane. To be

Examples of the compound in which n is 3 include the following compounds. Trimethylchlorosilane, methoxytrimethylsilane, ethoxytrimethylsilane, methoxydimethyl-3,3,3-trifluoropropylsilane, 3-
Chloropropylmethoxydimethylsilane, methoxy-3
-Mercaptopropylmethylmethylsilane and the like.

As the organosilicon compound represented by the general formula (2), an organosilicon compound represented by the following general formula (1) is preferably used.

In the general formula (1) R-Si-X ₃ , R is an alkyl group, an aryl group, X is a methoxy group,
Represents an ethoxy group and a halogen group.

In the organosilicon compound represented by the general formula (1), an organosilicon compound in which R is an alkyl group having 4 to 8 carbon atoms is more preferred, and a specific preferred compound example is trimethoxy. Examples thereof include n-butylsilane, trimethoxy i-butylsilane, trimethoxyhexylsilane, and trimethoxyoctylsilane.

As a preferred reactive organosilicon compound used for the final surface treatment, a polysiloxane compound can be mentioned. The molecular weight of the polysiloxane compound is 1000.
Those having a size of up to 20,000 are generally easily available, and also have a good function of preventing the occurrence of image memory such as black spots. In particular, when methylhydrogenpolysiloxane is used for the final surface treatment, good effects can be obtained.

Another surface treatment of titanium oxide of the present invention is titanium oxide particles which are surface-treated with an organic silicon compound having a fluorine atom. It is preferable to carry out the surface treatment with the organosilicon compound having a fluorine atom and the above-mentioned wet method.

That is, the above-mentioned organosilicon compound having a fluorine atom is dissolved or suspended in an organic solvent or water, untreated titanium oxide is added thereto, and such a solution is stirred for about several minutes to 1 hour. Then, the mixture is mixed, and if necessary subjected to heat treatment, dried through a step such as filtration to coat the titanium oxide surface with an organosilicon compound having a fluorine atom. The organosilicon compound having a fluorine atom may be added to a suspension prepared by dispersing titanium oxide in an organic solvent or water.

Incidentally, the fact that the titanium oxide surface is coated with an organic silicon compound having a fluorine atom means that
Photoelectron spectroscopy (ESCA), Auger electron spectroscopy (Au)
ger), secondary ion mass spectrometry (SIMS), and diffuse reflection FI-IR.

Fluorine atom-containing organosilicon compounds used in the present invention include 3,3,4,4,5,5,5.
6,6,6-nonafluorohexyltrichlorosilane,
3,3,3-trifluoropropyltrimethoxysilane, methyl-3,3,3-trifluoropropyldichlorosilane, dimethoxymethyl-3,3,3-trifluoropropylsilane, 3,3,4,4,5 , 5, 6, 6,
6-nonafluorohexyl methyl dichlorosilane etc. are mentioned.

In the present invention, the N-type semiconductive fine particles may be subjected to the last surface treatment with a reactive organic titanium compound or a reactive organic zirconium compound. The surface treatment method is carried out by a method similar to the surface treatment method using the above reactive organic silicon compound.

The fact that the surface of the N-type semiconductive fine particles is coated with the reactive organic titanium compound or the reactive organic zirconium compound means that the surface is covered with photoelectron spectroscopy (ESC).
A), Auger electron spectroscopy (Auger), secondary ion mass spectrometry (SIMS), diffuse reflection FI-IR, and other surface analysis techniques are used in combination to be highly accurately confirmed.

Specific reactive organotitanium compounds used for the surface treatment of the N-type semiconductive fine particles include metal alkoxide compounds such as tetrapropoxytitanium and tetrabutoxytitanium, diisopropoxytitanium bis (acetylacetate), Examples include metal chelate compounds such as diisopropoxytitanium bis (ethylacetoacetate), diisopropoxytitanium bis (lactate), dibutoxytitanium bis (octylene glycolate), diisopropoxytitanium bis (triethanolaminate). . Examples of the reactive organic zirconium compound include metal alkoxide compounds such as tetrabutoxyzirconium and butoxyzirconium tri (acetylacetate), and metal chelate compounds.

Next, the surface-treated titanium oxide particles and other N-type semiconducting fine particles (hereinafter also referred to as surface-treated N-type semiconducting fine particles. In particular, surface-treated titanium oxide is used. The structure of the intermediate layer in which particles are also referred to as surface-treated titanium oxide) will be described.

The intermediate layer of the present invention is a conductive solution prepared by dispersing surface-treated N-type semiconductive fine particles such as surface-treated titanium oxide obtained by performing the surface treatment a plurality of times in a solvent together with a binder resin. It is prepared by coating on a support.

The intermediate layer of the present invention is provided between the conductive support and the photosensitive layer, and improves the adhesion between the conductive support and the photosensitive layer, and has a barrier function for preventing charge injection from the support. Have. As the binder resin for the intermediate layer, a thermosetting resin such as a polyamide resin, a vinyl chloride resin, a vinyl acetate resin, a polyvinyl acetal resin, a polyvinyl butyral resin, a polyvinyl alcohol resin, a melamine resin, an epoxy resin or an alkyd resin, or a resin thereof. And a copolymer resin containing two or more of the repeating units of. Among these binder resins, a polyamide resin is particularly preferable, and an alcohol-soluble polyamide such as copolymerized or methoxymethylolated is particularly preferable.

The amount of the surface-treated N-type semiconductive fine particles of the present invention dispersed in the binder resin is, for example, in the case of surface-treated titanium oxide, 10 to 10,000 parts by mass relative to 100 parts by mass of the binder resin. Part, preferably 50-
1,000 parts by mass. By using the surface-treated titanium oxide in this range, the dispersibility of the titanium oxide can be kept good, and a good intermediate layer can be formed without causing image memory such as black spots.

The thickness of the intermediate layer of the present invention is 0.5 to 15 μm.
Is preferred. By using the film thickness within the above range, it is possible to form an intermediate layer having good electrophotographic characteristics without causing image memory such as black spots.

The coating solution for the intermediate layer prepared to form the intermediate layer of the present invention is the surface-treated N such as the surface-treated titanium oxide.
It is composed of mold semiconductive fine particles, a binder resin, a dispersion solvent and the like, and as the dispersion solvent, the same solvent as that used in the preparation of other photosensitive layers is appropriately used.

That is, the solvent or dispersion medium used for forming the intermediate layer, photosensitive layer and other resin layers of the present invention is n-
Butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N, N-dimethylformamide, acetone, methylethylketone, methylisopropylketone, cyclohexanone, benzene, toluene, xylene, chloroform, dichloromethane, 1,2-dichloroethane, 1 , 2-dichloropropane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethane, tetrahydrofuran, dioxolane, dioxane, methanol, ethanol, butanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, Methyl cellosolve and the like can be mentioned.

The solvent for the coating liquid for the intermediate layer is not limited to these, but methanol, ethanol, butanol, 1-propanol, isopropanol and the like are preferably used. Further, these solvents can be used alone or as a mixed solvent of two or more kinds.

As the solvent for coating the intermediate layer, it is preferable to use a mixed solvent of methanol and a linear alcohol having high resin solubility in order to prevent uneven drying during coating of the intermediate layer. The ratio of the linear alcohol to the methanol is 1 to 0.05 by volume.
A mixture of 6 is preferable. By using the coating solvent as a mixed solvent in this way, the evaporation rate of the solvent can be appropriately maintained, and the occurrence of image defects due to uneven drying during coating can be suppressed.

As a dispersing means for the surface-treated titanium oxide used for preparing the coating solution for the intermediate layer, any dispersing means such as a sand mill, a ball mill or ultrasonic dispersing may be used.

As the coating processing method for producing the electrophotographic photosensitive member of the present invention including the above-mentioned intermediate layer, dip coating,
Although coating processing methods such as spray coating and circular amount regulation type coating are used, the coating processing on the upper layer side of the photosensitive layer does not dissolve the lower layer film as much as possible, and in order to achieve uniform coating processing, spray coating or circular coating It is preferable to use a coating processing method such as regulated coating (a circular slide hopper is a typical example). Regarding the spray coating, for example, JP-A-3-
No. 90250 and JP-A-3-269238, and the circular amount control type coating is described in detail, for example, in JP-A-58-189061.

Next, the constitution of the photoreceptor of the present invention other than the intermediate layer will be described. In the present invention, the organic photoreceptor means an electrophotographic photoreceptor constituted by giving an organic compound either one of the charge generation function and the charge transport function, which is essential for the construction of the electrophotographic photoreceptor, It includes all known organic electrophotographic photoconductors such as a photoconductor composed of a known organic charge generating substance or an organic charge transporting substance, and a photoconductor comprising a polymer complex having a charge generating function and a charge transporting function.

The layer structure of the organic photoreceptor is not particularly limited, but an intermediate layer, a charge generating layer, a charge transporting layer, or a charge generating / charge transporting layer (functions of charge generating and charge transporting) are formed on a conductive support. A layer structure in which a photosensitive layer such as a layer having a) is provided, or a protective layer is further provided thereon.

Conductive Support The conductive support used in the photoreceptor of the present invention may be either a sheet or a cylinder, but in order to design the image forming apparatus compactly, the conductive support is cylindrical. A support is preferred.

The cylindrical conductive support means a cylindrical support necessary for forming an image endlessly by rotating, and has a straightness of 0.1 mm or less and a shake of 0.1 mm.
A conductive support in the following range is preferable. When the circularity and the shake range are exceeded, good image formation becomes difficult.

As the conductive material, a metal drum of aluminum, nickel or the like, a plastic drum on which aluminum, tin oxide, indium oxide or the like is deposited, or a paper / plastic drum coated with a conductive substance can be used. It is preferable that the conductive support has a specific resistance of 10 ³ Ωcm or less at room temperature.

The conductive support used in the present invention may have a surface on which a sealed alumite film is formed. The alumite treatment is usually carried out in an acidic bath of chromic acid, sulfuric acid, oxalic acid, phosphoric acid, boric acid, sulfamic acid, etc., but anodizing treatment in sulfuric acid gives the most preferable result. In the case of anodizing treatment in sulfuric acid, it is preferable that the sulfuric acid concentration is 100 to 200 g / L, the aluminum ion concentration is 1 to 10 g / L, the liquid temperature is about 20 ° C., and the applied voltage is about 20 V. It is not limited. The average thickness of the anodized film is usually 2
It is preferably 0 μm or less, and particularly preferably 10 μm or less.

Intermediate Layer In the present invention, the above-mentioned intermediate layer is provided between the conductive support and the photosensitive layer.

Photosensitive Layer The photosensitive layer structure of the photoconductor of the present invention may be a photosensitive layer structure having a single layer structure in which one layer has a charge generating function and a charge transporting function on the above-mentioned intermediate layer, but is more preferably photosensitive. It is preferable that the function of the layer is separated into a charge generation layer (CGL) and a charge transport layer (CTL). By adopting a constitution in which the functions are separated, the increase in residual potential due to repeated use can be controlled to be small, and other electrophotographic characteristics can be easily controlled according to the purpose. In the negative charging photoreceptor, the charge generation layer (C
GL) and a charge transport layer (CTL) thereon. In the case of the photoconductor for positive charging, the order of the layers is the reverse of that of the photoconductor for negative charging. The most preferable photosensitive layer structure of the present invention is a negatively charged photosensitive member structure having the above-mentioned function separation structure.

The constitution of the photosensitive layer of the function-separated negatively charged photoreceptor will be described below. Charge Generation Layer Charge Generation Layer: The charge generation layer contains a charge generation material (CGM). If necessary, a binder resin and other additives may be contained as other substances.

As the charge generating substance (CGM), a known charge generating substance (CGM) can be used. For example, a phthalocyanine pigment, an azo pigment, a perylene pigment, an azurenium pigment or the like can be used. Among these, CGM that can minimize the increase in residual potential with repeated use
Has a steric structure and a potential structure capable of forming a stable aggregation structure among a plurality of molecules, and specific examples thereof include a phthalocyanine pigment and a perylene pigment CGM having a specific crystal structure. For example, the Bragg angle 2θ with respect to Cu-Kα rays
CGMs such as titanyl phthalocyanine having a maximum peak at 27.2 ° and benzimidazole perylene having a maximum peak at 22.4 at 27.2 have almost no deterioration due to repeated use, and the residual potential increase can be reduced.

When a binder is used as a CGM dispersion medium in the charge generation layer, a known resin can be used as the binder, but the most preferable resin is formal resin, butyral resin, silicone resin, silicone modified butyral resin, phenoxy resin. Resin etc. are mentioned. The ratio of the binder resin to the charge generating substance is preferably 20 to 600 parts by mass with respect to 100 parts by mass of the binder resin. By using these resins, the increase in residual potential due to repeated use can be minimized. The thickness of the charge generation layer is preferably 0.01 μm to 2 μm.

Charge Transport Layer Charge Transport Layer: The charge transport layer contains a charge transport material (CTM) and a binder resin for dispersing CTM to form a film.
Other substances may optionally contain additives such as antioxidants.

As the charge transport material (CTM), a known charge transport material (CTM) can be used. For example, a triphenylamine derivative, a hydrazone compound, a styryl compound, a benzidine compound, a butadiene compound or the like can be used. These charge transport materials are usually dissolved in a suitable binder resin to form a layer. Among these, CTM that can minimize the increase in residual potential due to repeated use has high mobility and has a characteristic that the difference in ionization potential with CGM to be combined is 0.5 (eV) or less, and preferably 0. It is 0.25 (eV) or less.

The ionization potentials of CGM and CTM are measured by a surface analyzer AC-1 (manufactured by Riken Keiki Co., Ltd.).

Examples of the resin used for the charge transport layer (CTL) include polystyrene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd. Resins, polycarbonate resins, silicone resins, melamine resins, and copolymer resins containing two or more of the repeating units of these resins. In addition to these insulating resins, poly-
Examples include polymer organic semiconductors such as N-vinylcarbazole.

The most preferable binder for these CTLs is a polycarbonate resin. Polycarbonate resin is most preferable in improving dispersibility of CTM and electrophotographic characteristics. The ratio of the binder resin to the charge transport material is preferably 10 to 200 parts by mass with respect to 100 parts by mass of the binder resin. The thickness of the charge transport layer is preferably 10-40 μm.

Protective Layer The protective layer is preferably a protective layer which forms a surface layer having a low surface energy. For example, a protective layer of a siloxane-based resin layer, a protective layer containing a fluorine-based resin or the like is provided on the photosensitive layer. This is a good thing.

Although the layer structure of the most preferred photoconductor of the present invention has been illustrated above, a photoconductor layer structure other than the above may be used in the present invention.

Cleaning Roller As the cleaning roller 82, a conductive or semi-conductive and elastic cleaning roller is desirable.

A voltage having a polarity opposite to that of the toner involved in the development is applied to the cleaning roller 82 by the power source 84. That is, when development is performed with negatively charged toner and the negatively charged toner forms a toner image, a positive bias voltage is applied to the cleaning roller 82 by the power supply 84.

A rubber elastic body is used as the cleaning roller. As a material for such an elastic body, a conventionally known rubber such as silicone rubber or urethane rubber, a foam or a foam covered with a resin film is preferable.

Surface resistivity of cleaning roller (Ω)
Is normal temperature and humidity (temperature 26 ° C, relative humidity 50%), Mitsubishi Yuka's Hiresta IP (MPC-HT250), H
It is a value measured using an A probe at an applied voltage of 10 V and a measurement time of 10 seconds.

The thickness of the conductive or semi-conductive elastic layer depends on the surface resistivity and hardness of the material, but is generally about 0.
It is desirable to set the distance between 5 mm and 50 mm from the viewpoint of securing an appropriate resistance value and nip width. The volume resistivity of the roller material is preferably in the range of 10 ² Ωcm to ^{10 10} Ωcm.

The cleaning roller is preferably conductive or semiconductive and has a surface resistivity in the range of 10 ² Ω to ^{10 10} Ω. If the resistivity is lower than 10 ² Ω,
Banding due to discharge is likely to occur. Also,
If it is higher than 10 ¹⁰ Ω, the potential difference from the photoconductor becomes low, and cleaning failure tends to occur.

The cleaning roller is preferably rotated so that its abutting portion moves in the same direction as the surface of the photosensitive member. When the contact portion moves in the opposite direction, when excess toner is present on the surface of the image bearing member, the toner removed by the cleaning roller may spill and stain the recording paper or the apparatus.

When the photoconductor and the cleaning roller move in the same direction as described above, the surface speed ratio of the two is preferably in the range of 0.5: 1 to 2: 1. Outside this range, the speed difference between the two becomes large,
When foreign matter such as recording paper is caught between the photoconductor and the cleaning roller, the photoconductor may be damaged.

The hardness of the cleaning roller is 5 ° to 60 °.
Is preferable, and a range of 10 ° to 50 ° is particularly preferable. If the hardness is less than 5 °, the durability is insufficient and the hardness is 60.
If it exceeds 0, it becomes difficult to secure the contact width between the photoconductor and the cleaning roller, which is necessary for cleaning, and the surface of the photoconductor is easily scratched. In addition,
The hardness of the cleaning roller is a value measured by an Asker C hardness meter (load 300 gf) on the elastic body after being molded into the roller.

The contact width between the photosensitive member and the cleaning roller is preferably 0.2 mm to 5 mm, and 0.5 mm to 3 m.
The range of m is particularly preferable. If the contact width is less than 0.2 mm, the cleaning force is insufficient, and if it exceeds 5 mm, the photosensitive member is likely to be scratched by rubbing.

A bias voltage is applied to the bias voltage cleaning roller 82 by a power supply 84. The bias voltage is a voltage for electrostatically attracting and removing the toner adhering on the photoconductor 1 to the cleaning roller 82, and has a polarity opposite to the charging polarity of the toner. In this embodiment using the negatively charged toner, the bias voltage is positive. A constant current power supply is used as the power supply 84 for applying the bias voltage.

The constant current power source here is a power source configured to control the output voltage according to the resistance between the cleaning roller and the photoconductor so that a constant current value is always output.

After the transfer, there is electrostatic charge on the photoconductor 1,
Although the potential on the photoconductor 1 is not uniform, when a bias voltage is applied to the cleaning roller 82 from a constant current power source, when the toner is electrostatically attracted to the cleaning roller 82, it depends on the potential on the photoconductor 1. An almost constant electric field that is not generated is formed between the surface of the photoconductor 1 and the surface of the cleaning roller 82, a uniform cleaning effect is obtained, and an excellent cleaning effect is exhibited. Further, since a large potential difference is not locally generated, discharge is unlikely to occur.

The applied current value is 1 μA to 50 μ in absolute value.
The range of A is preferable. If it is smaller than 1 μA, the cleaning effect may be insufficient, and if it is larger than 50 μA, discharge or the like is likely to occur. Although this value varies depending on the type of the photoconductor and the resistance value of the cleaning roller, the organic photoconductor is dispersed in a resin to have a thickness of 10 μm to 3 μm.
The surface resistivity is 1 with the organic photoreceptor on which the photosensitive layer of 0 μm is formed.
When using a cleaning roller of 0 ² Ω to ^{10 10} Ω, the range of 5 μA to 40 μA is preferable.

Removing Means As shown in FIG. 2, it is preferable to remove a removed substance such as toner transferred from the photoconductor 1 to the cleaning roller 82 by bringing a scraper 89 as a removing means into contact with the cleaning roller 82.

As the scraper 89, an elastic plate such as a phosphor bronze plate, a polyethylene terephthalate plate, or a polycarbonate plate is used, and the trail method in which the tip forms an acute angle on the uncleaned side of the cleaning roller 82 or the tip is cleaned by the cleaning roller 82. The cleaning roller 82 may be contacted by any of the counter methods that form an acute angle on the finished side.

In addition to the scraper, a roller or a brush can be used as the removing means. The toner collected by the scraper 89 and the toner collected by the cleaning blade 81 are put into the developing unit 4 by the recycling unit 9 and reused. A plurality of removing means such as the scraper 89 may be provided. When the bias voltage is increased and the cleaning force of the cleaning roller 82 is increased, the toner is electrostatically strongly attached to the cleaning roller 82, so it is preferable to collect the toner with a plurality of scrapers.

Cleaning Blade The cleaning blade 81 is, as shown in FIG. 1, a counter system in which an acute contact angle θ is formed on the cleaned side of the photoconductor 1, and the cleaning edge at the tip thereof is on the surface of the photoconductor 1. The toner is scraped off from the photoconductor 1 by coming into contact therewith.

The load of the cleaning blade at the tip cleaning edge is preferably in the range of 0.1 N / m to 30 N / m, and particularly preferably in the range of 1 N / m to 25 N / m.

If the load is less than 0.1 N / m, the cleaning power will be insufficient and the cleaning will be incomplete.
Image stains easily occur. When the load is larger than 30 N / m, the surface of the photoconductor is greatly worn, and when the photoconductor is used for a long period of time, image blurring or the like is likely to occur. The load can be measured by pressing the tip of the cleaning blade against the scale or by electrically arranging a sensor such as a load cell at the pressure contact portion between the photoreceptor and the tip of the cleaning blade. The method etc. are used.

The contact angle θ of the tip of the cleaning blade with the photosensitive member is a value within the range of 0 ° to 40 °, particularly 0 °.
Values in the range of -25 ° are desirable. If the contact angle is larger than 40 °, the leading edge of the cleaning blade is turned over following the photoconductor and the blade is likely to be turned over. On the other hand, when the angle is smaller than 0 °, the cleaning power is lowered and the image is liable to be stained. An elastic body such as urethane rubber is used for the cleaning blade 81, and has a hardness of 2 measured according to JIS K-6253.
Those in the range of 0 ° to 90 ° are preferable.

If the angle is smaller than 20 °, the blade is too soft and the blade is likely to be turned over. Also, at greater than 90 °,
The ability to follow the slight unevenness of the photoconductor and foreign matter is insufficient,
Toner particles are easily removed. Hardness 60 ° -8
Those of 0 ° are particularly preferable.

The hardness of the cleaning blade is JIS
It is a value measured by K6301.

The thickness of the cleaning blade 81 is preferably in the range of 1 mm to 3 mm, and is 1.5 m.
The range of m to 2.5 mm is particularly preferable. The length of the portion not restricted by the blade holder 83, that is, the free length of the blade is preferably 2 mm to 20 mm, and 3 mm to 1
The range of 5 mm is particularly preferable.

A conventionally known elastic body such as polyurethane is used for the cleaning blade. As the toner used in the toner developing means 4, a toner produced by a conventionally known pulverization method of forming toner particles by pulverization or a granulation polymerization method of forming toner particles by polymerization can be used.

From the viewpoint of high image quality, the average deposition particle size is 8.5.
A toner having a particle size of not more than μm is desirable, and a toner having a particle size of not more than 7.0 μm is particularly preferable.

[0142]

EXAMPLES In the following examples, an image forming apparatus for a digital copying machine (scorotron charger, semiconductor laser) having elements for performing charging, exposing, developing, transferring, fixing and cleaning processes as shown in FIGS. Image formation was carried out using an exposure device).

A negatively chargeable OPC photoconductor is used as the present photoconductor, a negative electrostatic latent image is formed on the photoconductor, and a toner image is formed on the photoconductor by reversal development using negatively charged toner. did.

The moving speed of the photosensitive member is 370 mm in linear speed.
/ Sec, and the toner has a volume average particle diameter of 6.5 μm.
The negatively chargeable toner of was used. Photoreceptors Photoreceptors and comparative photoreceptors were prepared as described below.

Preparation of Coating Solution for Intermediate Layer A coating solution for intermediate layer used for preparing the photoreceptor of the present invention was prepared as follows.

(Preparation of coating liquid 1 for intermediate layer) 1 part by mass of polyamide resin CM8000 (manufactured by Toray Industries, Inc.), titanium oxide SMT
500 SAS (1st time: silica-alumina treatment, 2nd time: methylhydrogenpolysiloxane treatment: manufactured by Teika) 3 parts by mass and 10 parts by mass of methanol were added to the same container and a sand grinder (dispersion medium: glass beads) was used. By dispersing, an intermediate layer coating liquid 1 was prepared.

(Preparation of Intermediate Layer Coating Liquids 2 to 4) Intermediate layer coating liquid except that titanium oxide and its surface treatment and particle size, binder resin, titanium oxide / binder resin mass ratio and solvent are as shown in Table 1. Intermediate layer coating solutions 2 to 4 were prepared in the same manner as in 1.

(Preparation of intermediate layer coating solution 5) Intermediate layer coating solution 1 was coated in the same manner as intermediate layer coating solution 1 except that the second surface treatment of titanium oxide SMT500SAS was performed with diisopropoxytitanium bis (acetylacetate). Liquid 5 was prepared.

(Preparation of Intermediate Layer Coating Solution 6) Intermediate layer coating solution 6 was prepared in the same manner as Intermediate layer coating solution 1 except that the second surface treatment of titanium oxide SMT500SAS was performed with butoxyzirconium tri (acetylacetate). Was produced.

(Preparation of Intermediate Layer Coating Liquids 7 to 9: Comparative Example Intermediate Layer Coating Liquid) Table 1 shows titanium oxide and its surface treatment, particle size, binder resin, titanium oxide / binder resin mass ratio, and solvent type. Intermediate layer coating liquids 7 to 9 were prepared in the same manner as the intermediate layer coating liquid 1 except for the points shown.

(Preparation of Intermediate Layer Coating Liquid 10) Comparative Example Intermediate Layer Coating Liquid A middle layer coating liquid 10 was prepared by dissolving 1 part by weight of polyamide resin CM8000 (manufactured by Toray Industries, Inc.) and 10 parts by weight of methanol.

[0152]

[Table 1]

In Table 1, those listed in the primary treatment column are substances deposited on the surface of titanium oxide particles after the primary treatment,
The items described in the secondary treatment column indicate the substances used in the secondary treatment.

Preparation of Photoreceptor 1 The intermediate layer coating liquid 1 was dip-coated on a cylindrical aluminum substrate to form an intermediate layer with a dry film thickness of 2.5 μm. On top of that, the X-ray diffraction spectrum of the CuKα line (Bragg angle 2θ ±
0.2 degree) has a maximum diffraction peak at 27.2 degrees, 2 parts of a titanyl phthalocyanine compound, 1 part of butyral resin,
70 parts of t-butyl acetate, 4-methoxy-4-methyl-2
A liquid obtained by dispersing 30 parts of pentanone in a sand mill was applied by dip coating to form a charge generation layer having a dry film thickness of about 0.3 μm. Next, 0.65 parts of a charge transporting agent (compound A) and 1 part of a polycarbonate resin "Iupilon-Z200" (manufactured by Mitsubishi Gas Chemical Co., Inc.) dissolved in 7.5 parts of dichloroethane are dip-coated on the charge generation layer. A charge transport layer having a dry film thickness of about 24 μm was formed and dried at 100 ° C. for 70 minutes to prepare a photoconductor 1.

[0155]

[Chemical 1]

Preparation of Photoreceptors 2 to 10 The intermediate layer coating solutions 2 to 10 shown in Table 2 were used in place of the intermediate layer coating solution 1 used in the photoreceptor 1 and the intermediate layer was provided. Photosensitive members 2 to 10 were prepared in the same manner. The photoconductors 7 to 10 are comparative photoconductors.

Cleaning roller This is a cleaning roller made of conductive urethane foam, having a surface resistivity of 10 ³ Ω and a hardness of 30 °. The urethane roller is wound around a metal shaft of φ6 mm to be φ16 mm (thickness: 25 mm). The formed roller was brought into contact with the photoconductor so as to have a contact width of 2 mm.

The contact portion moves in the forward direction with respect to the photoconductor at a peripheral speed ratio of 1: 1. 20μA with constant current power supply for bias voltage cleaning roller
Was supplied, and a positive bias voltage was applied and a bias voltage was not applied (comparative example).

Removal means Two scrapers made of SUS were brought into contact with the cleaning roller by a counter method.

Cleaning blade thickness: 2.00 mm, free length: 10 mm, hardness: 70 °, cleaning blade made of urethane rubber, contact angle: 15
It was brought into contact with the photoconductor by a counter method of °. Contact weight is 2
It was 0 N / m.

5. A two-component developer composed of a toner and a carrier is used, and the toner has a volume average particle size of 6 produced by a granulation polymerization method.
The one having a thickness of 5 μm was used.

The following conditions were evaluated by combining the above-mentioned conditions with the above-mentioned respective photoconductors as shown in Table 2.

Each of the photoconductors was attached to the digital copying machine, and the conditions for applying the bias voltage to the cleaning roller were combined as shown in Table 2 (combination Nos. 1 to 1).
6), A4 paper in normal temperature and humidity (24 ° C, 60% RH) environment,
A line image having a pixel ratio of 7% was copied on 50,000 sheets. A white image was copied at the start and every 10,000 copies to evaluate the occurrence of image memory, the generation of black spots, and the cleaning property. The results are shown in Table 2.

Image Memory Evaluation Criteria The image memory was evaluated at the start and whether or not a line image was generated in the white image at every 10,000 copies.

A: No line image was generated. X: A line image was generated. Evaluation of cleaning property The cleaning property was also evaluated at the start and with a white image at every 10,000 copies.

○: No black spots due to toner slippage on white image ×: Black spots due to toner slippage on white image Black spot evaluation criteria Black spots are evaluated at the start and at a white image of every 10,000 copies. evaluated.

(Black spots) ○: 3 black spots of 0.1 mm or more / A4 or less Δ: 4 to 10 black spots of 0.1 mm or more / one or more occurrences of A4 ×: 0.1 mm or more 11 black spots / 1 or more occurrences of A4 or more

[0168]

[Table 2]

As is clear from Table 2, in the case where the photoreceptors 1 to 6 and 8 and 9 of the intermediate layer containing the surface-treated titanium oxide particles were used, the condition of applying the bias voltage to the cleaning roller (combination No. 1 to 6 and 8,
In 9), no image memory is generated and good cleaning property is achieved. On the other hand, when the photoreceptor 7 of the intermediate layer containing titanium oxide particles without surface treatment, which is outside the present invention, is used, image memory occurs and black spots often occur even under the condition that a bias voltage is applied to the cleaning roller. Also, black spots often occur when the photoreceptor 10 of the intermediate layer containing no titanium oxide is used. On the other hand, even if the photoreceptor of the intermediate layer containing the surface-treated titanium oxide particles is used,
It is found that the cleaning property is deteriorated under the condition that the bias voltage is not applied to the cleaning roller (combination Nos. 11 to 16).

[0170]

EFFECTS OF THE INVENTION By using the present invention, it is possible to provide an image forming apparatus and an image forming method which can achieve good cleaning properties without the occurrence of image memory and black spots.

[Brief description of drawings]

FIG. 1 is a diagram showing an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a cleaning unit of the image forming apparatus of FIG.

[Explanation of symbols]

1 photoconductor 2 charging means 3 exposure means 4 developing means 5 Transfer means 6 Separation means 7 fixing means 8 Cleaning means 9 Recycling means 81 cleaning blade 82 cleaning roller 84 power supply 89 scraper

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ identification code FI theme code (reference) G03G 15/08 507 G03G 21/00 312 21/10 326 318 15/08 507D 507L (72) Inventor Kazuhisa Shida Konica Stock Company, 2970 Ishikawa-cho, Hachioji-shi, Tokyo (72) Inventor Yuuo Endo Konica Stock Company, 2970, Ishikawa-cho, Hachioji-shi, Tokyo F-term (reference) 2H005 EA05 2H068 AA03 AA44 AA57 AA58 BB33 BB49 BB57 CA29 2H077 AA37 AC16 AD06 EA01 EA11 2H134 GA01 GB02 HA01 HA03 HA04 HA05 HA11 HA13 HA17 HD01 HD04 HD05 HD11 JA11 KD07 KD08 KD12 KG03 KG07 KG08 KH01

Claims (20)

[Claims] 1. A photoconductor, a latent image forming unit that forms an electrostatic latent image on the photoconductor, a developing unit that develops the electrostatic latent image on the photoconductor to form a toner image on the photoconductor, In an image forming apparatus having a transfer unit that transfers the toner image on the photoconductor to a recording material and a cleaning unit that cleans the photoconductor after the transfer, the cleaning unit is a conductive member that contacts the surface of the photoconductor. A cleaning roller having a semi-conductive elastic body, a cleaning blade arranged downstream of the cleaning roller in the moving direction of the photoconductor, and in contact with the surface of the photoconductor, and in developing by the developing means, From the cleaning roller and a constant current power source for applying a bias voltage having a polarity opposite to the charging polarity of the toner, which contributes to toner image formation, to the cleaning roller. The photosensitive member has an intermediate layer between the conductive support and the photosensitive layer, the intermediate layer is subjected to at least a binder resin and a plurality of surface treatments, and An image forming apparatus comprising an organic photoconductor containing N-type semiconductive fine particles, the surface treatment of which is performed using a reactive organosilicon compound. 2. A photoconductor, a latent image forming means for forming an electrostatic latent image on the photoconductor, a developing means for developing the electrostatic latent image on the photoconductor to form a toner image on the photoconductor, In an image forming apparatus having a transfer unit that transfers the toner image on the photoconductor to a recording material and a cleaning unit that cleans the photoconductor after the transfer, the cleaning unit is a conductive member that contacts the surface of the photoconductor. A cleaning roller having a semi-conductive elastic body, a cleaning blade arranged downstream of the cleaning roller in the moving direction of the photoconductor, and in contact with the surface of the photoconductor, and in the development by the developing means, From the cleaning roller and a constant current power source for applying a bias voltage having a polarity opposite to the charging polarity of the toner, which contributes to toner image formation, to the cleaning roller. A removing means for removing the toner, the photoreceptor has an intermediate layer between the conductive support and the photosensitive layer, the intermediate layer is subjected to at least a binder resin and a plurality of surface treatments, and An image forming apparatus comprising an organic photoconductor containing N-type semiconductive fine particles whose surface is treated with a reactive organotitanium compound. 3. A photoconductor, a latent image forming means for forming an electrostatic latent image on the photoconductor, a developing means for developing the electrostatic latent image on the photoconductor to form a toner image on the photoconductor, In an image forming apparatus having a transfer unit that transfers the toner image on the photoconductor to a recording material and a cleaning unit that cleans the photoconductor after the transfer, the cleaning unit is a conductive member that contacts the surface of the photoconductor. A cleaning roller having a semi-conductive elastic body, a cleaning blade arranged downstream of the cleaning roller in the moving direction of the photoconductor, and in contact with the surface of the photoconductor, and in developing by the developing means, From the cleaning roller and a constant current power source for applying a bias voltage having a polarity opposite to the charging polarity of the toner, which contributes to toner image formation, to the cleaning roller. The photosensitive member has an intermediate layer between the conductive support and the photosensitive layer, the intermediate layer is subjected to at least a binder resin and a plurality of surface treatments, and An image forming apparatus, characterized in that it is an organic photoreceptor containing N-type semiconductive fine particles whose surface is treated with a reactive organozirconium compound. 4. A photoconductor, a latent image forming means for forming an electrostatic latent image on the photoconductor, a developing means for developing the electrostatic latent image on the photoconductor to form a toner image on the photoconductor, In an image forming apparatus having a transfer unit that transfers the toner image on the photoconductor to a recording material and a cleaning unit that cleans the photoconductor after the transfer, the cleaning unit is a conductive member that contacts the surface of the photoconductor. A cleaning roller having a semi-conductive elastic body, a cleaning blade arranged downstream of the cleaning roller in the moving direction of the photoconductor, and in contact with the surface of the photoconductor, and in developing by the developing means, From the cleaning roller and a constant current power source for applying a bias voltage having a polarity opposite to the charging polarity of the toner, which contributes to toner image formation, to the cleaning roller. The photosensitive member has an intermediate layer between the conductive support and the photosensitive layer, and the intermediate layer has at least a binder resin and a hydrophobic surface-treated N-type semiconductive layer. An image forming apparatus, which is an organic photoreceptor containing fine particles. 5. The hydrophobized surface-treated N-type semiconductive fine particles are titanium oxide particles surface-treated with a reactive organosilicon compound having a fluorine atom. Image forming device. 6. The image forming apparatus according to claim 1, wherein the constant current power source outputs a constant current of 1 μA to 50 μA. 7. The cleaning roller has a resistance of 10 ² Ω.
The image forming apparatus according to claim 1, which has a surface resistivity of 10 ¹⁰ Ω. 8. The image forming apparatus according to claim 1, wherein the cleaning roller is made of an elastic material. 9. The image forming apparatus according to claim 1, wherein the cleaning roller is made of a foam material and a resin film covering the foam material. 10. The image forming apparatus according to claim 1, further comprising a recycling unit that supplies the toner collected by the cleaning unit to the developing unit and reuses the toner. 11. The image forming apparatus according to claim 1, wherein the removing unit includes a blade. 12. The image forming apparatus according to claim 1, wherein a plurality of the removing means are provided. 13. The image forming apparatus according to claim 1, wherein the photoconductor has a surface layer containing a siloxane resin having a crosslinked structure. 14. The image forming apparatus according to claim 1, wherein the photoconductor has a surface layer containing a siloxane-based resin having a structural unit having a charge transporting property. . 15. The photosensitive member has a conductive support, an intermediate layer, a photosensitive layer, and a surface layer containing a siloxane-based resin having a crosslinked structure, and a structure in which the layers are laminated in the order described above. The image forming apparatus according to claim 1, further comprising: 16. The cleaning blade is 0.1
The image forming apparatus according to claim 1, wherein cleaning is performed by contacting the photoconductor in a counter method with a weight of N / m to 30 N / m. 17. The cleaning blade is 0 ° to
2. The cleaning is performed by contacting the photoconductor by a counter method at a contact angle θ of 40 °.
The image forming apparatus according to any one of items 1 to 16. 18. The cleaning blade is 20 °
The image forming apparatus according to any one of claims 1 to 17, wherein the image forming apparatus is made of an elastic body having a hardness within a range of to 90 °. 19. The developing means has a volume average particle diameter of 3 μm.
The image forming apparatus according to any one of claims 1 to 18, wherein development is performed using a toner having a particle size of m to 8.5 µm. 20. An image forming method using the image forming apparatus according to claim 1.