JP2002189344A - Developing device and electrophotographic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device which ensures stable electrostatic chargeability of a developer in the passage of time and gives a uniform thin developer layer or suppresses the occurrence of a reversely charged toner and give a uniform stable thin toner layer even when a developer support is a rigid body. SOLUTION: The developing device has a layer thickness regulating member which regulates the thickness of a layer of a developer supported on the surface of a developer support and carried and at least the surface of the layer thickness regulating member is formed of a crosslinked methylmethoxy-containing nylon resin as a base.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device used for an image forming apparatus such as a copying machine, a printer, and a facsimile, and more particularly, to a developing device having a surface on which a one-component developer supplied by a developer supplying member is carried. The present invention relates to a developing device for forming a thin layer of the developer by bringing a layer thickness regulating member into contact with a developer carrier.

[0002]

2. Description of the Related Art Conventionally, a one-component developing apparatus supplies, charges, and attaches a developer to the surface of a developer carrier by means of an elastic roller such as a sponge that is driven to rotate, and then controls the thickness of the developer layer by using a blade or roller. The layer is regulated by a layer thickness regulating member to form a uniform thin developer layer on the surface of the developer carrier, and this is adhered and developed to an electrostatic latent image formed on the latent image carrier to produce a visible image. is there. At this time, the charging characteristics of the developer are affected by the frictional charging characteristics of each member. In the case of a negatively charging developer, the positive charging is performed for the purpose of increasing the amount of developer charging and decreasing the amount of the oppositely charged developer. In some cases, a material having a property is used as a surface member of the layer thickness regulating member.

[0003] In particular, nylon-based materials have a very strong positive charging property, and thus have been often used in the past for the purpose of improving the charging characteristics of a developer. For example, a copolymer of nylon and polyether (JP-A-9-5018)
5) Nylon having specific mechanical properties (JP-A-8-3
28381) and nylon formed on urethane rubber (Japanese Patent Application Laid-Open No. 8-248869). In addition, the developer carrier is roughly classified into a hard type and a soft type according to the shape of the photoreceptor (drum and belt) and the developing method (contact and non-contact), and a layer thickness regulating member corresponding to the type is required. Have been.

[0004]

However, since the nylon-based material has poor releasability, the developer adheres firmly to the surface of the layer thickness regulating member, so-called toner sticking occurs, and the charging characteristics of the developer are caused. Are fluctuated with time, and the phenomenon that stripes and unevenness occur in the thin developer layer occurs. Also, if the friction coefficient (μ) of the layer thickness regulating member is large, agglomerates and foreign matters of the toner are caught in the contact portion between the layer thickness regulating member and the developing roller, and streaks occur in the toner thin layer. Is difficult to obtain.

Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a developing device capable of obtaining a stable developer charging property with time and a uniform thin layer of the developer. It is. Still another object of the present invention is to provide a developing device in which generation of reversely charged toner is reduced. Another object of the present invention is to provide a developing device capable of obtaining a uniform and stable thin toner layer even when the developer carrier is rigid.

[0006]

According to a first aspect of the present invention, there is provided an image forming apparatus comprising: a developer carrier rotatably driven; and a developer carried on a surface of the developer carrier and conveyed. And a layer thickness regulating member for regulating the layer thickness of the agent,
The layer thickness regulating member is in pressure contact with the surface of the developer carrier via the developer, and the electrostatic latent image formed on the latent image carrier by the developer whose layer thickness is regulated by the layer thickness regulating member. In the developing device for visualizing the image, at least the surface of the layer thickness regulating member is formed mainly of a cross-linked methylmethoxy group-containing nylon resin.
The invention according to claim 2 is the developing device according to claim 1, wherein the methylmethoxy group-containing nylon resin is such that a crosslinking agent is a silane coupling agent. The invention according to claim 3 is the developing device according to claim 2, wherein the silane coupling agent is an aminosilane coupling agent. The invention according to claim 4 is the developing device according to claim 1, wherein a material formed on the surface of the layer thickness regulating member mainly with a methylmethoxy group-containing nylon resin has a volume resistance of 10 ¹² Ωcm or less. . The invention according to claim 5 is
The said developer carrying body has rigidity, The said thickness control member has an elastic layer, It has the structure mainly formed by the methyl methoxy group containing nylon resin which at least the surface was bridge | crosslinked. Developing device. The invention according to claim 6, wherein the methylmethoxy group-containing nylon resin has a crosslinking agent in an amount of 30 parts by weight or less based on 100 parts by weight of the methylmethoxy group-containing nylon resin. And

According to a seventh aspect of the present invention, there is provided an electrophotographic apparatus comprising at least a charging unit, an image exposing unit, a developing unit, a transferring unit, a cleaning unit, a discharging unit, and an electrophotographic photosensitive member. An electrophotographic apparatus as the developing apparatus according to any one of claims 1 to 6.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
FIG. 1 is a schematic diagram showing a configuration of a typical developing device useful for carrying out the developing device of the present invention, centering on a developer carrier. In FIG. 1, toner 24 contained in a toner tank 25 is supplied to a toner supply member (a sponge roller, a fur brush 1) by a stirring blade (toner supply member) 23.
4) and the toner 24 is forcibly brought to the toner supply member 22. On the other hand, the developer carrier 20 that has completed the development rotates in the direction of the arrow, and
2 to the contact area. The toner supply member 22 rotates in the forward or reverse direction with respect to the developer carrying member 20 to attach the toner 24 to the developer carrying member 20 while charging the toner 24. Further, the developer carrier 20 rotates, and the developer carrier 2 rotates.
The attached toner 24 on the zero is stabilized by the toner layer thickness regulating member 21 while controlling the thickness, and reaches the developing region 26. In the development area 26, the latent image is developed by contact or non-contact development. Here if necessary,
An optimal image can be controlled by applying a direct current, an alternating current, a superimposed direct current alternating current, a pulse, or the like to the developer carrier 20, the toner layer thickness regulating member 21, and the toner supply member 22.

Here, the surface of the toner layer thickness regulating member 21 greatly changes the charging characteristics of the developer, but if the releasability from the developer is poor, the developer adheres strongly to the surface of the toner layer thickness regulating member 21. That is, so-called "toner sticking" occurs, and the frictional charging property of the developer fluctuates, so that a stable charge amount cannot be obtained. Also, if irregularities or protrusions on the surface irregularities occur,
A uniform thin layer of the developer cannot be selected, resulting in unevenness of the thin layer and streaks caused by toner adhesion. In the present invention, the above problem can be prevented by forming the crosslinked alcohol-soluble nylon on at least the surface of the toner layer thickness regulating member 21.

The methylmethoxy group-containing nylon used on at least the surface of the toner layer thickness regulating member 21 of the present invention is obtained by methoxymethylating a part of amide groups in general nylon such as 6 nylon and 12 nylon. It can be represented by the following chemical structural formula.

Embedded image It has the characteristic that it is easily soluble in lower alcohols such as methanol, ethanol, propanol and butanol, and can be applied as a thin film by spraying or dipping.
Also, even if it is molded on a rubber roller, it does not crack because it is flexible and is suitable as a surface material of an elastic roller.

As a specific material, N- (methoxymethyl) nylon 12 (trade name: Toresin EF30T, F
30K, G550, manufactured by Teikoku Chemical Industry Co., Ltd./trade name: Fire Resin FR101, FR104, FR301,
(Produced by Lead City Co., Ltd.). In the present invention, the N- (methoxymethyl) nylon is an ethoxy-modified product, a butoxy-modified product, a Si-containing alcohol-modified product,
A modified product containing alkoxide is also used. The method for crosslinking the methylmethoxy group-containing nylon resin used in the present invention is represented by the following reaction formula in the presence of an acidic catalyst such as an organic acid such as citric acid, tartaric acid, or boric acid, or an inorganic acid such as hypophosphorous acid. As described above, there is a method in which intermolecular crosslinking is performed by a methanol removal reaction of a methylmethoxy group-containing nylon. Acidic catalyst _{-N-CH 2 -O-CH 3} + CH 3 -O-CH 2 -N- → -N-CH 2 -O-CH 2 -N-
+ 2CH ₃ OH

Further, any compound having a plurality of functional groups capable of reacting with a methylmethoxy group in a molecule can be used as a crosslinking agent. As typical methods, hydroxyl group,
There is a method in which a compound containing a methylol group or the like in a molecule is used as a crosslinking agent. In addition, not only low-molecular materials but also high-molecular materials can be used as long as they are compatible with a methylmethoxy group-containing nylon resin. For example, amino resins such as melamine resins, guanamine resins, and urea resins, and phenol resins. Can be mentioned. By using these crosslinking agents, the characteristics of the toner layer thickness regulating member 21 can be improved. The preferred crosslinking agent for the alcohol-soluble nylon used in the present invention is a silane coupling agent. The silane coupling agent is represented by the general formulas Y to SiX3, wherein Y is an organic functional group represented by amino, epoxy, vinyl, methacryl, and mercapto groups, and X is a hydrolyzable group represented by alkoxy group. Represents By crosslinking the methylmethoxy group-containing nylon resin with a silane coupling agent, μ of the toner layer thickness regulating member 21 is reduced. The lowering of the friction coefficient (μ) makes it easier to form a uniform and stable thin toner layer, and also achieves a reduction in torque and the like. The coefficient of friction (μ) is preferably 0.5 or less.

[0013] Silane coupling agents that can be used
In a chemical structural formula, a specific example of (CH_ThreeO)_ThreeSi-CH = CH_Two  (CH_ThreeCH_TwoO)_ThreeSi-CH = CH_Two  (CH_ThreeO)_ThreeSi- (CH_Two)_Three-O-CH_Two-CH-O-CH_Two  (CH_ThreeO)_ThreeSi- (CH_Two)_Two-C₆H_FourO (CH_ThreeO)_ThreeSi- (CH_Two)_Three-O- (CO) -C (CH_Three) = CH_Two  (CH_ThreeO)_ThreeSi- (CH_Two)_Three-SH (CH_ThreeO)_ThreeSi- (CH_Two)_Three-NCO (CH_ThreeO)_ThreeSi- (CH_Two)_Two-CF_Three  (CH_ThreeO)_ThreeSi- (CH_Two)_Three-O- (CH_TwoCH_TwoO)_nR etc.

In these molecules, the silane coupling agent
Amino silane coupling agents containing amino groups are the most
preferable. Since amino groups have electron donating properties, toner
24 can improve the triboelectrification property, especially in the toner band.
It is possible to increase the charge. Aminosilane cup
When a specific example of the ring agent is given by a chemical structural formula, (CH_ThreeO)_ThreeSi-(CH_Two)_Three-NH_Two  (CH3CH2O) 3Si- (CH_Two)_Three-NH_Two  (CH3O) 2Si (CH₃)-(CH_Two)_Three-NH_Two  (CH_ThreeO)_ThreeSi-(CH_Two)_Three-NH-ph (CH_ThreeO)_ThreeSi-(CH_Two)_Three-NH- (CH₃) (CH_ThreeO)_ThreeSi-(CH_Two)_Three-N (CH₃)₂  (CH_ThreeO)_ThreeSi-(CH_Two)_Three-N (CH_Two CH_Two CH_Two CH₃)_Two  (CH_ThreeO)_ThreeSi-(CH_Two)_Three-NH- (CH_Two)₂-NH_Two  (CH_ThreeO)_ThreeSi-(CH_Two)_Three-NH- (CH_Two)₆-NH_Two  (CH_ThreeO)_ThreeSi-(CH_Two)₂-ph-CH_Two-NH- (CH_Two)₂-NH_Two  Etc.

To add these catalysts and crosslinking agents to nylon, it is possible to directly knead them using a kneader, two-roll, three-roll, Banbury mixer, etc. And wet dispersion. Dispersion means for obtaining a dispersion by wet dispersion include a ball mill, an attritor, a sand mill, a vibration mill, a disk vibration mill, a paint shaker,
A known method such as a jet mill is used.
As a method of applying the coating liquid, a method such as a dip coating method, a spray coat, a beat coat, a nozzle coat, a spinner coat, and a ring coat can be used. These coating layers are sufficiently heated and dried under predetermined conditions to obtain a crosslinked layer. The heating conditions are as follows: temperature: 80 to 150
C, time: 10 minutes to 3 hours are preferred. By setting the volume resistance of the alcohol-soluble nylon formed on the surface of the toner layer thickness regulating member 21 of the present invention to 10 ¹² Ωcm or less, the amount of the oppositely charged toner on the developer carrier 20 can be reduced. is there. In addition, a bias can be applied between the developer carrier 20 and the developer-toner layer thickness regulating member 21.

For controlling the resistance of nylon, ordinary resistance control materials can be used, and these are roughly classified into conductive particles and ionic conductive materials. For example, conductive particles include conductive carbon black such as Ketjen black and acetylene black, conductive metal oxides such as tin oxide, titanium oxide and zinc oxide, metal particles such as nickel and copper, and graphite and pyrolytic carbon. And the like. In this case, the amount of the conductive particles to be added to 100 parts by weight of nylon is preferably 5 to 100 parts by weight. If the addition amount is less than 5 parts, the resistance will not be sufficiently reduced, and if it exceeds 100 parts by weight, the releasability will decrease and toner filming will occur.

Examples of the ionic conductive agent include tetraethylammonium, tetrabutylammonium, lauryltrimethylammonium, stearyltrimethylammonium, octadecyltrimethylammonium, dodecyltrimethylammonium, hexadecyltrimethylammonium, benzyltrimethylammonium and modified fatty acid dimethylethylammonium. Ammonium salts such as perchlorate, chlorate, hydrochloride, bromate, iodate, borofluoride, sulfate, alkyl sulfate, carboxylate and sulfonate; lithium, sodium,
Perchlorates, chlorates, hydrochlorides, bromates, iodates, borofluorides, trifluoromethyl sulfates, sulfonates, etc. of alkali metals or alkaline earth metals such as calcium and magnesium No. In these cases, the amount of the ionic conductive agent to be added is preferably 0.5 to 20 parts by weight based on 100 parts by weight of nylon. The amount added is 0.
If the amount is less than 5 parts, the resistance is not sufficiently reduced, and if it exceeds 20 parts by weight, the releasability is reduced and toner filming occurs. Further, in addition to the above-mentioned crosslinking agent and resistance controlling agent, various compounds, resins, particles, etc. are added to the nylon used for the toner layer thickness regulating member 21 of the present invention as needed in order to improve various characteristics. I can do it.

Next, the structure of the layer thickness forming member of the present invention will be described. The layer thickness forming member of the present invention only needs to be formed mainly of a methylmethoxy group-containing nylon resin having at least a surface crosslinked, and there is no limitation on the layer structure. For example, it is possible to mold a sheet or belt with a methylmethoxy-containing nylon resin alone to which a catalyst or a crosslinking agent is added and use it as the toner layer thickness regulating member 21, but most commonly, SUS, copper, Al or the like is used. It is used by forming a surface layer by coating on the surface of a metal, polymer sheet, roller, belt or the like. When the developer carrier 20 is a material lacking flexibility such as a metal or a hard resin, the layer thickness forming member of the present invention is preferably formed of a material mainly composed of a methylmethoxy group-containing nylon resin on the elastic layer. . This is because the flexibility of the layer thickness forming member makes it easy to follow the unevenness of the toner layer on the rigid developer carrier 20, and a uniform and smooth thin layer is obtained. Further, since the methyl methoxy group-containing nylon resin of the present invention has sufficient flexibility, there is no concern about cracks on the surface layer. The rubber hardness of the elastic layer is 80 degrees (JI
SA) The following is preferred. The thickness of the elastic layer is 100 μm to 1
0 mm is preferred. When a crosslinking agent is added to a methylmethoxy group-containing nylon resin and the crosslinking is performed, the amount of addition is 30.
It is preferably at most part by weight. If the amount exceeds 30 parts by weight, the flexibility of the nylon resin is impaired, and cracks occur.

As the material of the elastic layer, general rubber or thermoplastic elastomer can be used. Specifically, SBR (styrene butadiene rubber), BR (polybutadiene rubber), IR (isoprene rubber), IIR
(Butyl rubber) Halogenated but
yl rubber), NBR (nitrile butadiene rubber), hydrogenated NBR (H-NBR), EPDM (ethylene propylene rubber), C
R (chloroprene rubber), ACM (acrylic rubber) CO (hydrin rubber), chlorinated polyethylene (Chlorinated-PE),
Examples thereof include thermoplastic elastomers such as ethylene-acryl rubber, urethane rubber, silicone rubber, fluorine rubber, olefin, chlorine, polyester, polyether, polyamide, urethane, and fluorine.
It is also possible to add a resistance control agent to the elastic layer to make it conductive. A general conductive agent can be used, and the above-described conductive particles and ionic conductive agents can be used.

Next, a method of manufacturing the toner layer thickness regulating member 21 using an elastic roller will be described as a representative example. An elastic layer is formed on a conductive metal core (a metal such as SUS or Al or a conductive resin) by a general molding method such as extrusion molding, injection molding, press molding, or steam vulcanization molding.
In this case, it is also possible to use a primer between layers in advance in order to improve the adhesion and adhesion between the conductive core metal and the conductive layer. Next, the surface of the conductive layer is polished to a predetermined thickness, and then the methylmethoxy group-containing nylon of the present invention is molded. Nylon is sufficiently dissolved in advance with a lower alcohol such as methanol or ethanol, and a predetermined amount of the crosslinking agent is mixed and stirred. This coating liquid is applied by the method described above, and effect and drying are performed under predetermined conditions. After curing, the surface may be polished if necessary.

Next, an electrophotographic apparatus using the developing device of the present invention will be described in detail with reference to the drawings. FIG. 2 is a schematic diagram for explaining the electrophotographic apparatus of the present invention, and the following modified examples also belong to the category of the present invention.
In FIG. 2, this electrophotographic apparatus is close to the upper surface of the drum-shaped photoreceptor 1 and along the circumference in a counterclockwise direction.
Charge removing exposure unit 2, charging charger 3, eraser 4, image exposure unit 5, developing unit 6, pre-transfer charger 7, transfer charger 10, separation charger 11, separation claw 12, pre-cleaning charger 13, fur brush 14, cleaning brush 15. Are sequentially attached. Transfer paper 9
Is provided between the photosensitive member 1 and the transfer charger 10 and the separation charger 11. The photoreceptor 1 includes a drum-shaped conductive support and a photosensitive layer in close contact with the upper surface thereof, and rotates counterclockwise.
In the electrophotographic method using the above-described electrophotographic apparatus, the photoconductor 1 rotates counterclockwise, is negatively (or positively) charged by the charging charger 3, and is statically charged by the exposure from the image exposure unit 5. An electrostatic latent image is formed on the photoconductor 1.

The developer carrier 20 in the developing device of the present invention
Is placed opposite to the photoreceptor in a contact or non-contact state, and the toner 24 is transferred and developed from the developer carrier 20 onto the electrostatic latent image in the developing area 26, and the latent image is visualized. .

Next, a description will be given using an embodiment. (Examples 1 to 6, Comparative Examples 1 and 2)Layer thickness forming material prescription  A coating liquid was prepared based on the following table.

[Table 1] The coating solution is dipped on a SUS plate having a thickness of 100 μm, cured at 120 ° C. for 1 hour, and dried to obtain a surface layer having a thickness of 2 μm.
A member having a thickness of 0 μm was formed.

[0024]Evaluation items and evaluation methods  (I) Toner charge amount (q / m), development amount (m / a),
Gnar Release Property Test The layer thickness forming member was attached to the developing device of FIG. Section used
The materials are shown below. The developer carrier 20 includes a conductive elastic layer (1).
0⁵Ω, urethane rubber 4mm thick) / surface layer (silicone resin)
20 μm), and the supply roller is made of conductive urethane
Sponge and toner 24 are Ricoh color toner type
F (cyan) was used. Developer carrier 20, supply row
Grounding, and run idle for 500 hours (developer carrier 20
Linear speed 100mm / sec, supply roller linear speed 120mm /
sec), and the toner q / m, m / m
a (measured by the suction method) was measured. Also, the toner thin layer state
It was visually observed. After the test, the toner layer thickness regulating member 21
The toner 24 attached to the surface is removed with an air gun, and the toner
-The removability was evaluated according to the following rank.

(Ii) Coefficient of Static Friction (μ) The above-mentioned coating liquid was applied to a roller made of 16φAl, and cured under the same conditions to prepare a roller for μ measurement. The measurement was performed by the Euler belt method and μ was calculated. The friction partner is Ricoh's PPC paper type 6200.
The calculation formula is μ = ln (measured value / F) / (π / 2)
(F: measured load).

[Table 2]

(Examples 7 to 12) Formulation of layer thickness forming member, toner charge amount q / m, development amount m / m
a, Evaluation result of friction coefficient μ

[Table 3]

(Examples 13 to 17) Carbon black (Printex 90, manufactured by Degussa) was milled and dispersed in the same nylon and aminosilane coupling agent as in Example 10, and a layer thickness was formed in the same manner as in Examples 1 to 12. A member was prepared, and the electric resistance of the layer thickness forming member was controlled by adjusting the amount of carbon dispersion. Further, the toner charge amount q /
m and the development amount m / a were measured. Next, the developing device is
The toner was brought into contact with the photoreceptor 1 and the amount of the oppositely charged toner was evaluated by the following method. The linear velocity is such that the developer carrier 20 is 100 mm / sec,
The supply roller is 120 mm / sec.
At 66 mm / sec, the potential is
400 V, the supply roller is at +250 V, and the OPC photoconductor 1 is under 0 V process conditions.

After developing the oppositely charged toner 24 on the OPC photoreceptor 1 under the above conditions, the image was measured with a Macbeth densitometer by transferring the tape and pasting it on white paper. The same procedure was applied to the untransferred tape, and the inversely charged toner amount (ΔID) was calculated from the following equation. ΔID = ID (development) −ID (untransferred) Table 4 shows the results of the volume resistance and ΔID of the layer thickness forming member.

[Table 4]

(Embodiment 18)Production of layer thickness forming roller  Conductive elastic layer (12φ, made of shrimp chlorohydrin rubber, layer thickness
3 mm, 10⁸Ω, rubber hardness JISA58 °)
Spray coating using material No.11, 120 ° C / 1hr
Cured. Then, the surface is polished to a surface layer thickness of 15 μm.
A layer thickness forming roller 21 was obtained. This is shown in FIG.
Attached to the device. The developer carrier 20 has a surface
An Al roller subjected to a last treatment was used. Same as Example 1
When the spinning test was performed for 500 hours using the same method, the toner thin
A uniform and stable thin layer without streaks or unevenness on the layer
Was.

(Examples 19 to 22) The material used in Example 6 was spray-coated on the same conductive elastic layer as in Example 18 to obtain an elastic layer thickness regulating roller. (Example 19) In exactly the same manner, 20 parts by weight of melamine resin (Example 20) and 30 parts by weight (Example 2) with respect to 100 parts by weight of nylon.
1) A roller of 35 parts by weight (Example 22) was produced.
These were subjected to a spin test for 500 hours in the same manner as in Example 18, and cracks on the surface layer were observed with a microscope at a magnification of 200 times. As a result, no cracks occurred in Examples 19 and 20. In Example 21, three cracks occurred in the area (area corresponding to the non-image area) within 5 mm of both ends of the roller. However, there was no problem in practical use, and the degree of cracking was small.
In Example 22, cracks occurred in the central portion (image portion-corresponding region), and the thin toner layer in the crack portions was non-uniform.

(Example 23) The toner layer thickness regulating member 21, the developer carrier 20 and the developing device used in Example 1 were mounted on the electrophotographic apparatus shown in FIG. 2, and a running test of 100,000 sheets was performed. , Toner charge amount q / m before and after the test, development amount m
/ A, the background image density was measured.

[Table 5] After the test, toner adhesion of the toner layer thickness regulating member 21 did not occur.

[0032]

As described above, in the present invention, at least the surface of the layer thickness regulating member is formed mainly of a crosslinked methylmethoxy group-containing nylon resin, so that the layer thickness regulating member has a positive triboelectric chargeability and a separation property. A developing device having a layer thickness regulating member which is excellent in moldability and does not cause toner sticking can be obtained. In addition, by cross-linking a methylmethoxy group-containing nylon resin with a silane coupling agent with a silane coupling agent, the surface friction coefficient is reduced, a more uniform and stable thin layer can be formed, and torque can be reduced. Further, the use of an aminosilane coupling agent as a crosslinking agent for a methylmethoxy group-containing nylon resin increases the toner charge amount. Also,
When the volume resistance of the material mainly formed of a methylmethoxy group-containing nylon resin on the surface is 10 ¹² Ωcm or less, the amount of the oppositely charged toner on the developer carrier is reduced. Further, since the layer thickness regulating member having the elastic layer has a configuration in which at least the surface is mainly formed of a crosslinked methylmethoxy group-containing nylon resin, even when the developer carrying member is rigid, it is uniform and smooth. A layer is obtained. In addition, a material mainly composed of a methylmethoxy group-containing nylon resin is obtained by adding a crosslinking agent, and the amount of the crosslinking agent is reduced to 30 parts by weight or less based on 100 parts by weight of the methylmethoxy group-containing nylon resin. A layer thickness regulating member that does not cause cracking even when formed on a layer can be obtained. Further, at least charging means,
By mounting on an electrophotographic apparatus including an image exposing unit, a developing unit, a transferring unit, a cleaning unit, a discharging unit, and an electrophotographic photoreceptor, the chargeability of the toner is stabilized, and the image with less background contamination is stabilized. An electrophotographic apparatus obtained by the above method can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a typical developing device useful for carrying out the developing device of the present invention, focusing on a developer carrying member.

FIG. 2 is a schematic diagram for explaining the electrophotographic apparatus of the present invention.

FIG. 3 is a schematic diagram illustrating a configuration of a developing device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 10 Photoreceptor (latent image carrier) 2 Static elimination exposure part 3 Charger 4 Eraser 5 Image exposure part 6 Developing unit 7 Pre-transfer charger 8 Registration roller 9 Transfer paper 10 Transfer charger 11 Separation charger 12 Separation claw 13 Charger before cleaning Reference Signs List 14 fur brush 15 cleaning brush 20 developer carrier (developing roller) 21 layer thickness regulating member (layer thickness forming roller) 22 toner supply member 23 stirring blade 24 toner 25 toner tank 26 development area

Claims (7)

[Claims] An image forming apparatus comprising: a developer carrier that is driven to rotate; and a layer thickness regulating member that regulates a layer thickness of the developer carried and conveyed on the surface of the developer carrier. Is in pressure contact with the surface of the developer carrier through the developer, and the electrostatic latent image formed on the latent image carrier is visualized by the developer whose layer thickness is regulated by the layer thickness regulating member. The developing device according to claim 1, wherein at least the surface of the layer thickness regulating member is formed mainly of a cross-linked methylmethoxy group-containing nylon resin. 2. The developing device according to claim 1, wherein in the nylon resin containing a methylmethoxy group, a crosslinking agent is a silane coupling agent. 3. The developing device according to claim 2, wherein the silane coupling agent is an aminosilane coupling agent. 4. The volume resistance of a material mainly formed of a methylmethoxy group-containing nylon resin of the layer thickness regulating member on the surface thereof is 10 ¹² Ωcm or less.
3. The developing device according to claim 1. 5. A structure in which the developer carrier has rigidity, the layer thickness regulating member has an elastic layer, and is formed mainly of a methylmethoxy group-containing nylon resin having at least a surface cross-linked. The developing device according to claim 1, wherein: 6. The developing method according to claim 5, wherein the amount of the crosslinking agent added to the methylmethoxy group-containing nylon resin is 30 parts by weight or less based on 100 parts by weight of the methylmethoxy group-containing nylon resin. apparatus. 7. An electrophotographic apparatus comprising at least a charging unit, an image exposing unit, a developing unit, a transferring unit, a cleaning unit, a discharging unit, and an electrophotographic photosensitive member, wherein the developing unit comprises An electrophotographic device, which is a developing device.