JP3236454B2 - Regeneration charging member and method for regenerating charging member - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reproducing member and a method of reproducing a charging member used in an electrophotographic apparatus such as a laser beam printer, a copying machine and the like by an electrophotographic method .

[0002]

2. Description of the Related Art Conventionally, copiers, laser beam printers,
Various charging members used in an electrophotographic image forming apparatus such as a facsimile, for example, a developing charging roller,
Most of the transfer charging roller and the primary charging roller are discarded without being reused. Attempts have been made to reuse only a small number of metal rollers. For example, a method is known in which a roller is immersed in a cleaning solvent to remove dirt on the outer peripheral surface of the roller with a cleaning member such as a brush.

[0003]

Recently, ecology (the idea of coexisting gently with the global environment without abusing or polluting the global environment) has been spreading worldwide. However, most of the various charging rollers provided in the electrophotographic apparatus are discarded without being reused. Therefore, it was not favorable in terms of saving global resources and protecting the environment.

[0004] Most of the various charging rollers provided in the electrophotographic apparatus are made of synthetic resin, synthetic rubber, or the like. Due to the reasons (a) and (mouth) described in (1) above, it cannot be used as it is as a method for cleaning a roller made of synthetic resin or synthetic rubber.

(A) Synthetic resin or synthetic rubber is dissolved by a cleaning solvent or cracks are generated, and the electric resistance, hardness, surface roughness, roundness, straightness, slipperiness (friction coefficient), etc. Various functions required for such a roller may be impaired.

(Mouth) As for this type of roller, not only a single-layer structure using a single material but also a multi-layer structure in which two or more kinds of materials are laminated are often used. In the case of a multi-layer roller, the cleaning solvent may permeate from the end of the roller, so it is necessary to pay attention not only to the solvent resistance of the material of the surface layer but also to the solvent of the inner material. For this reason, the type of cleaning solvent to be used is limited, and the adhesive strength between the layers may be reduced.

In addition, there has been a problem that the electrical characteristics of various charging rollers deteriorate during use, and they do not exhibit sufficient electrical characteristics for reuse. The decrease in the electrical characteristics of the various charging rollers may be caused by deterioration of the surface of the charging roller due to the influence of ozone or the like generated by electric discharge, or wear of the surface of the charging roller due to contact with the member to be charged.

[0008] Further, if the various charging rollers whose electric characteristics are deteriorated as described above are reused without any means such as cleaning, the resistance value of the charging roller surface varies due to surface contamination, and charging unevenness occurs. There was a problem. This problem is likely to occur in a low-temperature, low-humidity environment.

An object of the present invention is to provide a reproducing charging member and a reproducing method of the charging member which do not cause the above-mentioned problems.

[0010]

SUMMARY OF THE INVENTION The first invention, (A) at least one of at least one (B) magnetic polystyrene resin and polyester resin (C) silica and metal oxides, among
(A) and (C), or an image forming apparatus using a powder developer containing (A), (B) and (C) as a main component, wherein a voltage is applied to charge the surface of the member to be charged. in playback charging member a member is reused, spent
On the surface of the charging member, a layer of the powder developer is formed.
Is, the volume resistivity above this layer 10 ⁴ to 10 ¹⁴ [Omega] cm
It is characterized by being formed by applying a cover layer .

[0011]

[0012]

According to a second aspect, in the first aspect, the coating layer has a thickness in a range of 1 to 1000 μm.

According to a third aspect of the present invention, in any one of the above aspects, the charging member has a roller shape.

[0015] A fourth invention, (A) at least one (B) magnetic polystyrene resin and polyester resin (C) at least one of silica and metal oxides, among
(A) and (C), or an image forming apparatus using a powder developer containing (A), (B) and (C) as a main component, wherein a voltage is applied to charge the surface of the member to be charged. Element
The for reusing, in the reproducing method of the charging member, using
On the surface of the used charging member, a layer of the powder developer is provided.
Is formed, the volume resistivity on this layer is 10 ⁴ ~10 ¹⁴ Ωc
m to form a recharging member by applying a coating layer
Characterized in that it.

As the voltage applied to the charging member, any of a DC voltage, a superimposed voltage of a DC voltage and an oscillating voltage (for example, an AC voltage) and the like can be used.

The present invention is effective as a method for reusing a charging roller used in an electrophotographic apparatus. In a charging roller used in an electrophotographic apparatus, a powder developer (toner) or the like adheres to the surface during use, and the toner adhered to the surface causes a variation in resistance value on the surface of the charging roller, causing uneven charging. There is a problem. It is not easy to completely remove the toner and the like adhering to the surface of the charging roller.

Further, there is a problem that the surface of the charging roller is deteriorated during use due to the influence of electric discharge and friction with the member to be charged.

However, the present invention provides a charging roller having such a problem by forming a coating layer on the outer periphery of the charging roller to make the resistance value of the charging roller surface uniform and to provide sufficient electric characteristics as a charging member. It recovers the state and enables reuse as a charging roller. In addition,
The layer having the components (A), (B) and (C) referred to in the present invention means a layer to which toner has adhered.

Next, the schematic structure of the charging member of the present invention will be described.

The charging member 2 of the present invention is in the form of a roller, and has a conductive cored bar 2a, a conductive elastic layer 2b integrally formed on the outer periphery thereof, and a resistance formed on the outer periphery of the conductive elastic layer. A control layer 2d, a protective layer 2c formed on the outer periphery of the resistance control layer 2d to which a powder developer (toner) adheres, and a coating layer 2e formed on the outer periphery of the protective layer 2c to which the powder developer is adhered. It is configured. The used charging roller before reproduction may have a configuration of a conductive elastic layer 2b without the resistance control layer 2d and a protective layer 2c as shown in FIG. 2, or a conductive roller without the resistance control layer 2d and the protective layer 2c. The configuration of the elastic elastic layer 2b may be used. Also in this case, the charging roller 2 having the coating layer 2e formed on the outer periphery of the roller to which the powder developer has adhered can be obtained.

FIG. 1 is a schematic diagram showing an example of an electrophotographic apparatus (laser beam printer) using a contact charging device using a charging member according to the present invention as a primary charging means of an image carrier.

Reference numeral 1 denotes a rotating drum type electrophotographic photosensitive member (hereinafter, referred to as a photosensitive drum) as a member to be charged, which is driven to rotate at a predetermined peripheral speed (process speed) in a clockwise direction indicated by an arrow. 1a is a conductive drum base made of aluminum or the like of the photosensitive drum 1, and 1b is a photosensitive layer formed on the outer peripheral surface of the drum base 1a.

Reference numeral 2 denotes a contact charging member, and in this embodiment, a roller body (hereinafter, referred to as a charging roller) arranged in pressure contact with a predetermined pressing force in parallel with the drum generatrix direction of the surface of the photosensitive drum 1.
Then, the photosensitive drum 1 is driven to rotate.

The charging roller 2 of this embodiment is a core metal (2) for applying a DC voltage or a superimposed voltage of a DC voltage and an AC voltage.
a) a conductive elastic layer (2) for imparting elasticity and conductivity;
b) If necessary, a resistance control layer (2d) for controlling the resistance of the charging member is formed thereon, and a protective layer (2c) is formed outside the conductive elastic layer or outside the resistance control layer when the resistance control layer is provided.
Is provided. A powder developer (toner) adheres to the surface of the protective layer 2c. In this configuration, a coating layer (2e) is formed outside the protective layer 2c to which the powder developer has adhered. The powdery developer adhered to the conductive elastic layer 2b, the resistance control layer 2d, the protective layer 2c, the coating layer 2e, and the protective layer 2c of the charging roller 2 of this embodiment will be described later.

Reference numeral 3 denotes a power supply for applying voltage to the charging roller 2, and a conductive core (shaft) of the charging roller 2 is supplied from the power supply.
By applying a predetermined voltage to 2a, the surface of the rotating photosensitive drum 1 is charged to a predetermined potential by a contact charging method.

The voltage applied to the charging roller 2 may be a DC voltage only or a DC voltage with an oscillating electric field such as an AC voltage superimposed thereon. In terms of uniform charging, it is more advantageous to superimpose an oscillating electric field.

Exposure means 4 (not shown) for exposing according to image information of a document to form an electrostatic latent image around the surface of the photosensitive drum 1 uniformly primary-charged to a predetermined potential by the charging roller 2, A developing device 5 for attaching toner to the electrostatic latent image to form a toner image, a transfer charger 7 for transferring the toner image on the photosensitive drum to a transfer material P supplied from a paper feed cassette 6,
A cleaning device 9 for removing residual toner on the photosensitive drum 1 after transfer, and a pre-exposure unit 10 (not shown) for removing charges on the photosensitive drum 1 in preparation for the next primary charging are arranged. Further, a fixing device 8 for fixing the toner image transferred onto the transfer material P to the transfer material P is disposed downstream of the transfer charger 7.

The conductive metal core 2a used in the present invention comprises:
A round bar of a metal material such as iron, copper, stainless steel, aluminum, and nickel can be used. Further, these metal surfaces may be subjected to plating treatment for the purpose of rust prevention and imparting scratch resistance, but it is necessary that the conductivity is not impaired.

In the charging roller 2, the conductive elastic layer 2b
Are provided with appropriate conductivity and elasticity in order to supply power to the photosensitive drum 1 as an object to be charged and to ensure good uniform adhesion of the charging roller 2 to the photosensitive drum 1. In order to ensure uniform adhesion between the charging roller 2 and the photosensitive drum 1, the conductive elastic layer 2b may be polished so as to have a shape in which the central portion is thickest and becomes thinner toward both ends, that is, a so-called crown shape. Many. Since the generally used charging roller 2 is brought into contact with the photosensitive drum 1 by applying a predetermined pressing force to both ends of the cored bar 2a, the pressing force at the center is small, and the pressing force at the both ends is larger. Therefore, there is no problem if the straightness of the charging roller 2 is sufficient, but if it is not sufficient, density unevenness may occur in the images corresponding to the central portion and both ends. The crown shape is formed to prevent this.

The conductivity of the conductive elastic layer 2b is adjusted by adding a conductive agent such as carbon black to an elastic material such as rubber. The elasticity is adjusted by adding a process oil, a plasticizer or the like. Specific elastic materials of the conductive elastic layer 2b include, for example, natural rubber, synthetic rubber such as EPDM, SBR, silicon rubber, urethane rubber, IR, BR, NBR, CR, and polyamide resin, polyurethane resin, and silicon resin. And the like. Further, a foam of the above-described elastic material may be used for the conductive elastic layer 2b.

The resistance control layer 2d is often provided to control the resistance of the charging member. Specific examples of the material for the resistance control layer 2d include resins such as polyamide resin, polyurethane resin, fluorine resin, and silicone resin, as well as epichlorohydrin rubber, urethane rubber, chloroprene rubber, and acrylonitrile rubber. Conductive particles such as carbon black and carbon graphite and conductive metal oxides such as tin oxide and titanium oxide are also used for the resistance control layer 2d.
A conductive agent such as an alkali metal salt or an ammonium salt is often dispersed.

The protective layer 2c is often provided to prevent bleed-out of the plasticizer or the like in the conductive elastic layer 2b to the surface of the charging roller. Specific materials for the protective layer 2c include polyamide resin, polyurethane resin, fluororesin,
Resins such as silicone resin, and further include epichlorohydrin rubber, urethane rubber, chloroprene rubber, acrylonitrile rubber, and the like. In order to provide the protective layer 2c with appropriate conductivity, conductive particles such as carbon black and carbon graphite, conductive metal oxides such as tin oxide and titanium oxide, alkali metal salts and ammonium salts are used. Agents are often dispersed.

As described above, the powder developer contains the following components as main components.

(A) at least one of a polystyrene resin and a polyester resin (B) a magnetic material (C) at least one of a silica and a metal oxide As the polystyrene resin (A component), for example,
Polystyrene, poly-p-chlorostyrene, homopolymer of styrene of polyvinyltoluene and its substituted product or styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene- Styrene-based copolymers such as acrylate copolymers and styrene-butadiene copolymers are exemplified.

Further, examples of the polyester resin (component A) include the following.

As the dihydric alcohol component, ethylene glycol, propylene glycol, butanediol, diethylene glycol, triethylene glycol, pentanediol, hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A Or a derivative of bisphenol.

Examples of the divalent acid component include benzenedicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid and phthalic anhydride or anhydrides thereof, lower alkyl esters, and succinic acid, adipic acid, sebacic acid and azelaic acid. Alkyl dicarboxylic acids or anhydrides thereof, lower alkyl esters, or n-dodecenyl succinic acid,
Alkenyl succinic acids or alkyl succinic acids such as n-dodecyl succinic acid, anhydrides and lower alkyl esters thereof, or unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid and itaconic acid or anhydrides thereof, lower alkyl Examples include dicarboxylic acids such as esters and derivatives thereof.

Further, a trivalent or higher valent alcohol component and a trivalent or higher valent acid component which also function as a crosslinking component may be used in combination.

The polyhydric alcohol component having three or more valences includes
Sorbitol, 1,2,3,6-hexanetetrol,
1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,2
4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2
And trihydric or higher polyhydric alcohols such as -methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1, З, 5-trihydroxybenzene.

Examples of the trivalent or higher polycarboxylic acid component include:
Trimellitic acid, pyromellitic acid, benzenetricarboxylic acid, naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylene Carboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, embolic trimer acid, and their anhydrides, lower alkyl esters, tetracarboxylic acids, etc., and their anhydrides And polyvalent carboxylic acids such as lower alkyl esters and derivatives thereof.

Examples of the magnetic material (component B) include iron oxides such as magnetite, hematite, and ferrite, and metals such as iron, cobalt, and nickel, or aluminum, cobalt, copper, lead, magnesium, tin, and the like of these metals.
Examples include alloys of metals such as zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, and vanadium, and mixtures thereof.

As the silica (C component), an untreated fine powder may be used, or a silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, a silane coupling agent, a silane coupling having a functional group. Agents, other treating agents such as organosilicon compounds,
Alternatively, those treated in combination with various treatment agents may be used.

Examples of the metal oxide (component C) include cerium oxide, titanium oxide, aluminum oxide, zinc oxide, antimony oxide, tin oxide and the like.

The coating layer 2e of the present invention has a volume resistivity of 1
0 ⁴ 10 ¹⁴ good to use a thermoplastic elastomer and synthetic rubber in the range of [Omega] cm. If necessary, a conductive agent may be contained for the purpose of resistance adjustment or the like.

Examples of the thermoplastic elastomer used for the coating layer 2e include acrylic resins such as polyurethane resin, polymethyl methacrylate, and polybutyl methacrylate, polyvinyl butyral resin, polyvinyl acetal resin, polyarylate resin, polycarbonate resin, polyester resin, and phenoxy resin. , Polyvinyl acetate resin, polyvinyl pyridine resin, cellulose resin, polyvinyl alcohol resin, polyamide resin, RB (butadiene resin), fluororesin, silicone resin, SBS, S
High molecular compounds such as polystyrene and polyolefin such as IS and SEBS can be used. In particular, when a coating layer is formed by coating with a coating, polyurethane resin, acrylic resin, polyester resin, fluororesin, silicone resin, and polyamide resin are preferable in that they are suitable for coating.

Examples of the synthetic rubber used for the coating layer 2e include epichlorohydrin rubber, urethane rubber, chloroprene rubber, acrylonitrile rubber and the like.

The conductive agent used for the purpose of adjusting the resistance or the like of the coating layer 2e includes conductive particles such as carbon black and carbon graphite, and conductive agents such as conductive titanium oxide, conductive zinc oxide and conductive tin oxide. Metal oxides or alkali metal salts and ammonium salts.

The thickness of the coating layer 2e is 1 to 10 OOμ.
m, more preferably in the range of 2 to 300 μm.

The volume resistivity of the coating layer 2e is 1
0 ⁴ is preferably in the range of to 10 ¹⁴ [Omega] cm.

In the present invention, a primer or the like may be used between the protective layer 2c and the coating layer 2e for the purpose of strengthening the adhesion between the protective layer 2c and the coating layer 2e.

The charging member having the configuration as in the present invention enables the charging member to be reused. In addition, the electrical characteristics of the charging member can be sufficiently ensured, and an output image quality substantially equal to that of a new charging member can be obtained.

The measurement of the volume resistivity in the present invention is performed according to JI
This was performed according to SK6911.

[0054]

Embodiments of the present invention will be described below.

Example 1 A charging roller 2 as a charging member according to the present invention was prepared in the following manner.

A laser beam printer (trade name “LBP-
8Mark IV "Canon Inc.", a process cartridge (model name: EP-E toner cartridge), after performing image printing of 50000 sheets, take out the charging roller 2 'from the process cartridge, and form the charging roller 2 according to the present invention. Used as base. A powder developer (toner) adheres to the surface of the removed charging roller 2 '. The outer diameter of the charging roller is 12 mm.

After lightly blowing the charging roller 2 'with air, a coating layer 2e as shown below was formed.

As a material for the coating layer 2e, a coating for the coating layer 2e is prepared by dispersing and dissolving 1 part by weight of methylolated nylon and 20 parts by weight of conductive titanium oxide in a mixed solvent of methanol / toluene. This coating material was applied on the charging roller 2 'by a dipping method to form a coating layer 2e having a thickness of 10 μm, thereby obtaining a charging roller 2 according to the present invention.

The resistance value of the obtained charging roller 2 was changed to a temperature 2
At 3.5 ° C. and 50% humidity (environment 1), charging roller 2
A 10mm width aluminum foil is tightly wound around the circumference of
A DC voltage (250 V) is applied between the support and the aluminum foil, and a resistance meter “HIOKI 3119DEGITAL MΩ” is applied.
HI TESTER (Hioki Electric Co., Ltd.) ". Table 1 shows the results.

[0060]

[Table 1]

The charging roller 2 is incorporated into an unused process cartridge (trade name: EP-E toner cartridge) and a laser beam printer as shown in FIG. 1 (trade name "LBP-8Mark IV", Canon Inc.)
Used as the charging roller 2 at the position of the primary charger of
An image endurance test was performed on 000 images. The images were evaluated by visually observing the images obtained at the initial stage and after the running of 6000 sheets. Table 2 shows the results.
In the table, ○ indicates that the obtained image is good, Δ indicates practical use, and X indicates
Indicates that it is not practical.

[0062]

[Table 2]

The above-mentioned image output durability test was conducted at a temperature of 2
3.5 ° C, humidity 50% (environment 1) and temperature 15 °
C, humidity 10% (environment 2), temperature 30 ° C, humidity 80
% (Environment 3).

(Example 2) In Example 1, the coating layer 2
Evaluation was performed in the same manner as in Example 1 except that a water-based polyurethane emulsion solution (solid content: 10%) was used as a material for e as a coating material for the coating layer 2e. The results are shown in Tables 1 and 2.

(Example II) The coating layer 2e in Example 1
As a material for the above, 100 parts by weight of a polyurethane resin and 10 parts by weight of a conductive carbon black are dispersed and dissolved in a methyl ethyl ketone (MEK) solvent to prepare a coating material for the coating layer 2e, and the coating material is dipped on the charging roller 2 '. The evaluation was performed in the same manner as in Example 1 except that the coating layer 2e having a thickness of 200 μm was formed. The results are shown in Tables 1 and 2.

(Example 4) The coating layer 2e of Example 3
The evaluation was performed in the same manner as in Example 1, except that 1 part by weight of lithium perchlorate was used instead of the conductive carbon black used in Example 1, and a coating layer 2e of 20 μm was formed. Tables 1 and 2 show the results.
Shown in

(Embodiment 5) The coating layer 2e of the first embodiment
As a material for the above, except that 100 parts by weight of a fluororesin was dispersed and dissolved in 30 parts by weight of tin oxide with an N-methylpyrrolidone (NMP) solvent to prepare a coating for the coating layer 2e, and that a coating layer 2e of 15 μm was prepared. Evaluation was performed in the same manner as in Example 1. The results are shown in Tables 1 and 2.

(Example 6) In the same manner as in Example 1, except that the charging roller 2 'taken out of the process cartridge after outputting 5000 sheets of images was wiped dry with a cleaning wiper instead of an air blower. An evaluation was performed. The results are shown in Tables 1 and 2.

Example 7 Evaluation was performed in the same manner as in Example 6, except that the cleaning roller was wiped with MEK (methyl ethyl ketone) to wipe off the charging roller 2 '. The results are shown in Tables 1 and 2.

When the surface of the charging roller wiped with a cleaning wiper moistened with MEK was subjected to infrared absorption analysis and X-ray microanalysis, polystyrene resin (A component), magnetic substance (B component), and silica (C component) were detected. Was done. Even if the charging roller 2 'to which the toner is attached is wiped off with a solvent such as MEK, the attached toner cannot be completely removed.

(Embodiment 8) Copying machine (product name "FC33
0 "Canon process cartridge (model name; Canon cartridge E (blue)"), which is used for Canon Inc.), after taking out 2000 images, the charging roller 2 'is taken out from the color process cartridge, and the charging of the present invention is performed. Used as a base for Roller 2. A powder developer (toner) adheres to the surface of the removed charging roller 2 '. The powder developer contains no component (B) (A),
(C) is a non-magnetic toner. The outer diameter of the charging roller is 12 mm.

After lightly blowing the charging roller 2 ′, a coating layer 2 e similar to that of the first embodiment is formed.
I got

The resistance value of the obtained charging roller 2 was measured in Example 1.
It was evaluated similarly. Table 1 shows the results.

The charging roller 2 is not used in a process cartridge (trade name: Canon cartridge E30).
(Black) ① and a copier (trade name “FC33
0 "Canon Inc.) to carry out an endurance test on 4,000 images. Table 2 shows the results.

The above-mentioned image output durability test was conducted at a temperature of 2
3.5 ° C, humidity 50% (environment 1) and temperature 15 °
C, humidity 10% (environment 2), temperature 30 ° C, humidity 80
% (Environment 3).

(Example 9) In Example 5, the coating layer 2
Before applying the coating material for e, a silane coupling agent “γ- (2-aminoethyl) aminopropylmethyldimethoxysilane” is applied as a primer to the surface of the charging roller 2 ′ by a dipping method, and dried. Evaluation was performed in the same manner as in Example 5 except that the coating layer 2e was formed thereon. The results are shown in Tables 1 and 2.

(Comparative Example 1) A process cartridge (model name: EP-E toner cartridge) used in a laser beam printer (trade name “LBP-8Mark IV” Canon Inc.) outputs 5000 images, and then performs image formation. The charging roller 2 'was taken out of the process cartridge. A powder developer (toner) adheres to the surface of the removed charging roller 2 '.

The charging roller 2 ′ is directly incorporated into an unused process cartridge (trade name: EP-E toner cartridge), and a laser beam printer “LBP-8Mark IV (Canon)” as shown in FIG. 1 is used. The same evaluation as in Example 1 was performed using the charging roller 2 at the position of the primary charger. Tables 1 and 2 show the results.
Shown in

In environment 2, the second half of the image output durability test (4
(500 sheets), in the halftone image area, charging unevenness due to contamination of the charging roller 2 'was slightly generated.

(Comparative Example 2) A process cartridge (model name: EP-E toner cartridge) used in a laser beam printer (trade name “LBP-8Mark IV” Canon Inc.) outputs 5000 images, and then performs image formation. The charging roller 2 'was taken out of the process cartridge. A powder developer (toner) adheres to the surface of the removed charging roller 2 '.

In order to cleanly remove the toner from the surface of the charging roller 2 ′, the toner was strongly washed with a cleaning wiper moistened with MEK. After cleaning, the charging roller 2 'had a small pinhole in the protective layer 2c on the surface, and the lower layer 2d was visible, and could not be reused as it was.

[0082]

As described above, according to the present invention, the charging roller used in the electrophotographic apparatus can be reused, which contributes to saving of earth resources and environmental protection.

Further, in the present invention, when the charging roller is regenerated, cleaning with an organic solvent is not required, so that there is no occurrence of cracks on the surface of the charging roller due to the organic solvent cleaning. Therefore, there is no danger that various functions required for the charging roller such as electric resistance, hardness, surface roughness, roundness, straightness, and slipperiness (friction coefficient) are lost due to generation of cracks or the like.

Further, since the charging roller according to the present invention sufficiently secures electric characteristics as a charging member in an electrophotographic apparatus, stable output image quality and durability can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an example of an electrophotographic apparatus in which a contact charging device using a charging member according to the present invention is used as a primary charging unit of an image carrier.

FIG. 2 is a schematic configuration diagram of a contact-type charging member showing another embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... To-be-charged body (photosensitive drum) 2 ... Charging roller as a charging member 2a ... Conductive metal core 2b ... Conductive elastic layer 2c ... Protective layer 2d ... Resistance control layer 2e ... Coating layer 3 ... Power supply 4 ... Exposure means 5 Developing device 6 Paper cassette 7 Transfer charger 8 Fixing device 9 Cleaning device 10 Pre-exposure device P Transfer material

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-149018 (JP, A) JP-A-6-19370 (JP, A) JP-A-4-177377 (JP, A) JP-A 64-64 73365 (JP, A) JP-A-5-224502 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/02

Claims (4)

(57) [Claims] (A) at least one of a polystyrene resin and a polyester resin; (B) a magnetic substance; (C) at least one of silica and a metal oxide; (A) and (C), or (A) and (B) and
The (C) is used in an image forming apparatus using a powder developer as a main component, in the reproduction charging member to which a voltage is applied reused a charging member for charging processing to be charged member surface, the used charge On the surface of the member, a layer of the powder developer is provided.
Is formed, the volume resistivity on this layer is 10 ⁴ ~10 ¹⁴ Ωc
m . A regenerated charging member formed by applying a coating layer of m . 2. The charging member according to claim 1 , wherein the thickness of the coating layer is in the range of 1 to 1000 μm. 3. A playback charging member according to claim 1 or 2, wherein said charging member is roller-shaped. 4. (A) at least one of a polystyrene resin and a polyester resin (B) a magnetic substance (C) at least one of silica and a metal oxide (A) and (C), or (A) and (B) and
Used in an image forming apparatus using a powder developer containing (C) as a main component, and used in a charging member regenerating method for reusing a charging member to which a voltage is applied to charge a surface of a member to be charged . A layer of the powder developer on the surface of the charging member.
There is formed, a volume resistivity above this layer 10 ⁴ to 10 ¹⁴ Omega
cm of the rechargeable member by coating
A method for regenerating a charging member.