JP3539682B2 - Method of manufacturing conductive roller - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a conductive roller used for an electrophotographic apparatus such as a laser beam printer (LBP) and a copying machine, and more particularly to a method for manufacturing a conductive roller suitably used for a developing roller, a charging roller, a transfer roller, a cleaning roller, and the like. It relates to a manufacturing method. The conductivity in the present application means a semiconductive region of about 10 ³ to 10 ¹² Ω · cm.
[0002]
[Prior art]
Epichlorohydrin rubber can easily control a volume resistivity of about 10 ⁶ to 10 ¹⁰ Ω · cm in a semiconductive region of 10 ³ to 10 ¹² Ω · cm, and has a small variation in electric resistance in the roller. For this reason, it has been conventionally used as a base polymer of a resistance adjusting layer such as a developing roller, a charging roller, and a transfer roller. Specifically, a conductive elastic layer is provided on the outer peripheral surface of the conductive shaft, a resistance adjusting layer made of epichlorohydrin rubber is provided on the outer peripheral surface of the conductive elastic layer, and a protective layer is further provided on the outer peripheral surface of the resistance adjusting layer. Is provided.
[0003]
However, epichlorohydrin rubber has a disadvantage that the environmental stability of the volume resistivity is poor, and the volume resistivity increases in a low-temperature and low-humidity environment and decreases in a high-temperature and high-humidity environment.
[0004]
The resistance adjustment layer is set as a high resistance layer that controls the electrical resistance of the roller.However, when epichlorohydrin rubber is used as the base polymer of the resistance adjustment layer, it is particularly susceptible to the effects of temperature and humidity, and the output value of the power supply is reduced. By adjusting to temperature and humidity, the disadvantage of epichlorohydrin rubber is compensated. Therefore, a device or the like for adjusting the output of the power supply is required, and there has been a problem that the cost of the electrophotographic apparatus itself is increased.
[0005]
In addition, epichlorohydrin rubber may contaminate the photoreceptor due to low molecular weight components, vulcanization reaction residue, and the like, and a protective layer is usually provided on the outside thereof.
[0006]
However, epichlorohydrin rubber easily swells in organic solvents, so when forming a protective layer using a coating solution, the surface of the epichlorohydrin layer swells due to the solvent, depending on the type of solvent in the coating solution, and bubbles are generated. For example, the surface state deteriorates, and the epichlorohydrin layer is destroyed. In particular, epichlorohydrin rubber easily swells with organic solvents such as methyl ethyl ketone (abbreviation MEK), dimethylformamide (abbreviation DMF), and toluene.
[0007]
When using a resin in which a conductivity-imparting material or the like is dispersed in the protective layer, if the epichlorohydrin rubber swells with an organic solvent, there is a problem in that the drying speed of the solvent varies, and the volume resistivity is not stable.
[0008]
[Problems to be solved by the invention]
An object of the present invention is to use epichlorohydrin rubber as a base polymer of a conductive elastic layer, to take advantage of an advantage that electric resistance can be controlled within three digits within a semiconductive region, and to be stable against environmental changes such as temperature and humidity. An object of the present invention is to provide a method for producing a conductive roller having a reduced electric resistance and having no defects in appearance due to bubbles or the like.
[0009]
[Means for Solving the Problems]
In the present invention, a rubber composition obtained by kneading a compounding agent containing a conductive filler with epichlorohydrin rubber on the outer peripheral surface of a conductive shaft is vulcanized to have a volume resistivity of 10 ⁶ to 10 ¹⁰ Ω · cm. Forming a conductive elastic layer,
An inner layer having a thickness of 1 μm or more and 20 μm or less of a resistance adjusting layer is formed on the outer peripheral surface of the conductive elastic layer using a coating liquid in which N-methoxymethylated nylon is dissolved or dispersed in an alcohol or aqueous solvent. Process and
In at least one or more solvents selected from the group consisting of methyl ethyl ketone, dimethylformamide and toluene, at least one or more hydrophobic resins selected from the group consisting of polyester polyurethane resins, polycarbonate polyurethane resins and silicone polyurethane resins are dissolved or Forming an outer layer having a thickness of 0.5 μm or more and 100 μm or less on the outer peripheral surface of the inner layer of the resistance adjusting layer by using the dispersed coating liquid. Roller manufacturing method.
The present invention also provides a vulcanized rubber composition obtained by kneading a compounding agent containing a conductive filler with epichlorohydrin rubber on the outer peripheral surface of a conductive shaft body, and vulcanizing the rubber composition to obtain a volume resistivity value of 10 ⁶ to 10 ¹⁰ Ω · cm. Forming a conductive elastic layer that is
Forming an inner layer having a thickness of 1 μm or more and 20 μm or less on the outer peripheral surface of the conductive elastic layer using a coating liquid in which an aqueous urethane acrylic resin is dissolved or dispersed in an alcohol-based or aqueous solvent; ,
In at least one or more solvents selected from the group consisting of methyl ethyl ketone, dimethylformamide and toluene, at least one or more hydrophobic resins selected from the group consisting of polyester polyurethane resins, polycarbonate polyurethane resins and silicone polyurethane resins are dissolved or Forming an outer layer having a thickness of 0.5 μm or more and 100 μm or less on the outer peripheral surface of the inner layer of the resistance adjusting layer by using the dispersed coating liquid. Roller manufacturing method.
Further, in the present invention, the inner layer has a volume resistivity value of 10 ¹⁰ Ω · cm,
The outer layer has a volume resistivity of 10 ¹¹ Ω · cm.
[0010]
According to the present invention, at least a two-layer structure of an inner layer made of a hydrophilic resin and an outer layer made of a hydrophobic resin is provided on the outer periphery of the conductive elastic layer made of epichlorohydrin rubber, and the outer layer is more electrically resistant than the inner layer and the conductive elastic layer. By using a high-resin resin, it is possible to provide a conductive roller having a stable electric resistance that has a small change with respect to environmental changes such as temperature and humidity due to the hydrophobic resin layer on the surface.
[0011]
[0012]
According to the present invention, the resistance adjusting layer has at least a two-layer structure, and the inner layer is formed of a hydrophilic resin dissolved in an aqueous or alcoholic solvent, in particular, by using N-methoxymethylated nylon, thereby forming a conductive layer. The swelling of the epichlorohydrin rubber constituting the elastic layer due to the solvent can be prevented. The inner layer formed using N-methoxymethylated nylon acts as a sealing layer for the solvent when the outer layer is formed using a hydrophobic resin dissolved or dispersed in a solvent such as methyl ethyl ketone, dimethylformamide and toluene. In addition, the swelling of epichlorohydrin rubber by these solvents can be prevented.
[0013]
[0014]
By including the conductive filler in the conductive elastic layer, it is possible to provide a conductive roller in which the influence of temperature and humidity is reduced while controlling the electric resistance within a range of three digits using epichlorohydrin rubber.
[0015]
[0016]
According to the present invention, by setting the thickness of the inner layer of the resistance adjusting layer to 1 μm or more and 20 μm or less, the inner layer functions as a sealing layer for a solvent when the outer layer of the resistance adjusting layer is formed, and the epichlorohydrin of the conductive elastic layer is formed. It is preferable because it is possible to provide a conductive roller that prevents the rubber from swelling due to the solvent and has a stable volume specific resistance value against environmental changes such as temperature and humidity.
[0017]
[0018]
[0019]
[0020]
According to the present invention, it is possible to manufacture a conductive roller which is hardly affected by environmental changes from high temperature and high humidity to low temperature and has stable electric resistance.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a conductive roller for an electrophotographic apparatus of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of the conductive roller 1, and FIG. 2 is a cross-sectional view perpendicular to the axis of the conductive roller 1 of FIG. The conductive roller 1 includes a conductive shaft 2, a conductive elastic layer 3 formed on the outer peripheral surface of the shaft 2, and a resistance adjusting layer 4 laminated on the outer peripheral surface of the conductive elastic layer 3. It has a multilayer structure. The shaft body 2 is a slender right circular column shape whose both ends are pivotally supported and whose both ends are precision machined for fitting a drive component, and a metal, for example, iron, aluminum alloy, stainless steel or the like is suitably used.
[0022]
The conductive elastic layer 3 comprises epichlorohydrin rubber as a base rubber, and kneading a compounding agent such as carbon black, a vulcanizing agent, a vulcanization accelerator, a deterioration inhibitor, a softener, and a filler with a rubber kneading roll or kneader. A kneaded rubber composition is obtained, supplied to the periphery of the shaft body 2, and heated and vulcanized to be formed. The rubber composition using epichlorohydrin rubber as a base rubber has a feature that it can be easily controlled to a volume resistivity within three orders of magnitude in a semiconductive region of 10 ³ to 10 ¹² Ω · cm as described above. . As the conductive filler for imparting conductivity to the conductive elastic layer 3, carbon black or metal oxide particles such as titanium oxide, tin oxide, and zinc oxide can be used. Carbon black is preferably used because it has good dispersibility in rubber and excellent reinforcement.
[0023]
The volume resistivity of the conductive elastic layer 3 of the conductive roller of the present application is preferably 10 ⁶ to 10 ¹⁰ Ω · cm.
[0024]
However, epichlorohydrin rubber has drawbacks that it is easily swelled by an organic solvent and has poor environmental stability of volume resistivity due to having a hydroxyl group. In order to correct these drawbacks, a resistance adjusting layer 4 is provided on the outer peripheral surface of the conductive elastic layer 3.
[0025]
The resistance adjusting layer 4 is formed in a laminated structure of at least two layers, an inner layer 4a made of a hydrophilic resin and an outer layer 4b made of a hydrophobic resin. The inner layer 4a is formed using a coating liquid in which a hydrophilic resin is dissolved or dispersed in a water-based or alcohol-based solvent. Epichlorohydrin rubber is stable to water-based or alcohol-based solvents. Therefore, when the inner layer 4a is formed, the epichlorohydrin rubber of the conductive elastic layer 3 does not swell with these solvents and does not cause a variation in the volume specific resistance of the conductive roller 1.
[0026]
As the hydrophilic resin constituting the inner layer 4a, for example, N-methoxylated nylon resin and aqueous urethane acrylic resin can be used. Among them, N-methoxymethylated nylon has an affinity for epichlorohydrin and has high strength. Is preferred. When the inner layer 4a is formed using these hydrophilic resins, the inner layer 4a functions as a sealing layer for an organic solvent. Therefore, when forming the outer layer 4b, an organic solvent such as methyl ethyl ketone, dimethylformamide, and toluene is used. However, the epichlorohydrin rubber of the conductive elastic layer 3 does not swell.
[0027]
The thickness of the inner layer 4a is preferably 1 μm or more and 20 μm or less. When the thickness is smaller than 1 μm, the sealing property with respect to the above-mentioned organic solvent is weak and insufficient, and when the thickness is larger than 20 μm, the electric resistance is easily affected by environmental changes such as temperature and humidity. More preferably, it is 2 to 10 μm.
[0028]
The outer layer 4b of the resistance adjusting layer 4 is made of a hydrophobic resin. By using a hydrophobic resin, a change in electrical resistance due to a change in environment such as temperature and humidity as a roller can be reduced (about one digit). The thickness of the outer layer 4b is preferably about 0.5 μm or more and 100 μm or less in order to achieve the above object.
[0029]
Examples of the hydrophobic resin constituting the outer layer 4b include thermoplastic polyester polyurethane resin, polycarbonate polyurethane resin, and silicone polyurethane resin. These resins may be used alone or in combination of two or more.
[0030]
When the electric resistance of the roller obtained by removing the resistance adjusting layer 4 from the conductive roller 1 of FIG. 1 is R ₁ and the electric resistance of the conductive roller 1 is R ₂ , R ₁ is in the range of 10 ⁶ to 10 ⁸ Ω. It is preferable that a resistance difference be provided between the conductive elastic layer 3 and the resistance adjusting layer 4 so that the resistance ratio R ₂ / R ₁ is 10 or more, preferably 10 ^1.5 or more. As a result, even if the change in the environment from high temperature and high humidity to low temperature and low humidity causes a change in the electric resistance of the conductive elastic layer 3, the influence on the electric resistance of the roller is reduced, and the environmental fluctuation of the roller resistance is reduced. can do.
[0031]
Although the resistance adjustment layer 4 in FIG. 1 has a two-layer structure, it may have a multilayer structure as another embodiment of the present invention. Further, a protective layer may be provided on the outer peripheral surface of the resistance adjusting layer for the purpose of protecting the conductive roller and preventing contamination. As the protective layer, a fluorine resin, a fluorine-based polymer, a silicone resin, a silicone-based polymer, a resin composition containing an additive thereof, and the like can be used.
[0032]
The method of manufacturing the conductive roller 1 is as follows. A shaft formed by kneading a kneaded rubber composition obtained by kneading a conductive filler and a vulcanizing agent with epichlorohydrin rubber is filled in a roller molding die that is held at the center of the shaft. Then, by heating and vulcanizing, a roller molded body in which the conductive elastic layer 3 is formed integrally with the shaft body 2 is obtained. The outer periphery of the formed conductive elastic layer 3 may be further polished to adjust its surface properties. Next, the resistance adjusting layer 4 is formed on the conductive elastic layer 3 by a dip coating method or a coating method using a coating roller. In the case of the dip coating method, the roller molded body is immersed in a coating liquid in which a hydrophilic resin and an additive are dissolved or dispersed in an alcohol-based or aqueous-based solvent, and then dried to form an inner layer 4a of the resistance adjusting layer 4. To form Similarly, the outer layer 4b is formed on the outer peripheral surface of the inner layer 4a using a coating liquid in which a hydrophobic resin and an additive are dissolved or dispersed in a solvent of methyl ethyl ketone, dimethylformamide and toluene. As the solvent used for the coating liquid, one of the above solvents may be used alone, or a mixed solvent may be used.
[0033]
FIG. 3 is a cross-sectional view showing a part of a laser printer 5 which is an electrophotographic apparatus including the conductive roller 1 of FIG. The photoreceptor 6, which is a right cylindrical drum, is provided with a negative charge, for example, uniformly on the surface thereof by the charging roller 7. The charged photoreceptor 6 is rotated in the direction of the arrow 8 to reach the exposure area 9, where the image is exposed by the laser beam from the exposure unit 11, the charge on the exposed portion is neutralized, and the image is exposed. An electrostatic latent image is formed.
[0034]
The photoreceptor 6 is further rotated and supplied with toner 14 by a developing roller 13 in a developing device 12. The toner 14 is negatively charged in frictional contact with each other by the stirring means 15 or the like in the developing device 12. The charged toner 14 is attached from the developing roller 13 to an exposed portion of the photoreceptor 6 where the charge has been neutralized by the electrostatic attraction, the electrostatic latent image is visualized, and the toner image 16 is developed. You. The toner image 16 is transferred onto the recording paper 18 by electrostatic force by the operation of the transfer roller 17 according to the rotation of the photoconductor 6, and the toner image 19 is thus transferred onto the recording paper 18. The toner image 19 is fixed on the recording paper 18 by an action such as heating or pressure.
[0035]
A power supply 25 applies a potential V1 of -1500 V to the shaft 23 of the charging roller 7. The charging roller 7 uniformly charges the photosensitive layer on the surface of the photoconductor 6 to, for example, -600V. A power supply 26 is connected between the shaft 2 of the conductive roller 1 for applying electric charges and the shaft 24 of the charging roller 7. Potential V2 of power supply 26 is, for example, -1000V. Thus, the potential V3 (= V1 + V2 = -2500V) with respect to the ground potential is applied to the shaft 2 of the conductive roller 1 for applying electric charges. The potential V1 (= -1500 V) applied to the charging roller 7 in this manner is the same polarity as the normal triboelectric charging polarity at the time of development of the toner 14 in the developing device 12, that is, in this embodiment, a negative potential is applied. . The potential V3 (= V1 + V2) applied to the conductive roller 1 for applying electric charge is the same polarity as the triboelectric charging polarity during the development of the toner 14 in the developing device 12, that is, the negative polarity. The value | V3 | is a value exceeding the absolute value | V1 | of the potential applied to the charging roller 7.
[0036]
After the transfer, the residual toner 21 remains and adheres to the surface of the photoconductor 6. After the transfer by the transfer roller 17, the residual toner 21 may be charged to a positive polarity that is opposite to the triboelectric charge during development. The positively charged residual toner 21 moves from the surface of the photoreceptor 6 to the surface of the charging roller 7, and comes into contact with the conductive roller 1 from the surface of the charging roller 7 as shown by reference numeral 28 and is rubbed. You. By the function of the charging roller 1, the residual toners 21 and 28 are charged to the negative polarity of the developing device 12 during development, that is, negatively charged. The process proceeds as indicated by reference numeral 32, whereby the toner 32 is collected in the developing device 12. Therefore, the surface of the photoconductor 6 and the surface of the charging roller are cleaned by the residual toner 21 in a cleanerless manner.
[0037]
The conductive roller 1 in FIG. 1 can be suitably used as the charging roller 7, the developing roller 13, the transfer roller 17, the cleaning roller, and the like in FIG. 3 in addition to the conductive roller 1 in FIG.
[0038]
Hereinafter, the conductive roller for an electrophotographic apparatus of the present invention will be specifically described with reference to examples. In addition, in the following, all parts indicating each component represent parts by weight.
[0039]
(Example 1)
Open roll with 100 parts of epichlorohydrin rubber (Zeklon G3100, manufactured by Zeon Corporation) and 27 parts of liquid NBR, 25 parts of carbon black, 100 parts of calcium carbonate, 5 parts of zinc oxide, 1 part of surface-treated sulfur, a vulcanization accelerator and a crosslinking assistant To prepare a kneaded rubber composition.
[0040]
Next, as shown in FIG. 4 (1), the kneaded rubber composition is formed into a tube (cylindrical roll material) 3 ′, and after passing through the shaft 2, the lower mold is formed as shown in FIG. 4 (2). One end of the shaft 2 was inserted into a recess 39 provided at the center of the lower mold 36 in a state where the upper mold 38 was removed from a mold in which a straight cylindrical middle mold 37 was assembled into 39. The upper mold 38 was attached to the middle mold 37 such that the other end of the shaft 2 was inserted into a recess 40 provided at the center of the upper mold 38. The inner diameter of the middle mold is about 8 mmφ, and the length is about 250 mm. The shaft body 2 is a steel rod (material: SUS301) having an outer diameter of 5 mmφ and a length of 250 mm. In the state shown in FIG. 4B, the axis of the shaft body 2 and the axis of the inner peripheral surface of the middle mold 37 coincide with each other.
[0041]
Next, the mold assembled with the lower mold 36, the middle mold 37, and the upper mold 38 was heated at 150 ° C. for 0.5 hour to be vulcanized. Thereafter, the molded product was removed from the mold to obtain a roller molded product, and the outer peripheral surface was ground to an outer diameter of 7 mmφ with a grinding machine to form a conductive elastic layer 3 having a thickness of 1 mm on the shaft 2.
[0042]
On the outer peripheral surface of the conductive elastic layer 3 thus formed, the resistance adjusting layer 4 is formed as shown in FIG. First, as shown in FIG. 5A, N-methoxymethylated nylon (Toresin F30K, manufactured by Teikoku Chemical Industry Co., Ltd.) was mixed with a mixed solvent of methanol and water at a 5: 1 (volume ratio) solid content. Was dissolved so as to be 10% by weight to prepare an inner layer coating liquid 42 having a dry volume resistivity of 10 ¹⁰ Ω · cm, and the conductive elastic layer 3 was immersed in the container 41. Thereafter, the conductive elastic layer 3 was pulled up together with the shaft body 2 and air-dried to form an inner layer 4a having a thickness of about 2 μm on the conductive elastic layer 3 as shown in FIG.
[0043]
Next, as shown in FIG. 5 (3), a polycarbonate polyurethane (ME-8200LP, manufactured by Dainichi Seika Kogyo Co., Ltd.) was added to a mixed solvent of DMF / toluene 80/20 (volume ratio) to a solid content of 30%. 7 parts of carbon black (MHI5732M, manufactured by Mitsubishi Chemical Corporation) dispersed in methyl ethyl ketone to a solid content of 20% in 100 parts of a solution obtained as described above, a toluene solution of a silicon graft copolymer (solid content: 20%) 0.2 part, 1 part of a DMF / ethyl acetate solution of a fluororesin and 75 parts of DMF and MEK as additives are added and dispersed by stirring, and the volume resistivity when dried is adjusted to 10 ¹¹ Ω · cm for the outer layer. The coating liquid 44 was prepared, and the conductive elastic layer 3 on which the inner layer 4a was formed was immersed in the container 43. Thereafter, the conductive elastic layer 3 is pulled up together with the shaft body 2 and dried with hot air to form an outer layer 4b having a thickness of 50 μm on the inner layer 4a as shown in FIG. Obtained.
[0044]
As shown in FIG. 6, the electric resistance value of the conductive roller 1 is such that a load of F ₁ and F ₂ = 500 g is applied to the shaft 2 at both ends of the conductive roller 1 on a metal (SUS) flat plate 50. The roller was pressed, a voltage of 1000 V was applied from the shaft body 2, and after 10 seconds, the electric resistance value of the roller was calculated from the current value flowing into the metal flat plate. The measurement was carried out under normal conditions (20 ° C., humidity 30%) at the center in the length direction and at three points 50 mm left and right from the center, and the average value was used as the measured value.
[0045]
The appearance of the obtained conductive roller 1 was free from defects such as bubbles, and the electric resistance was 1.0 × 10 ⁸ Ω. Further, the variation of the electric resistance in the rotation direction of the conductive roller 1 was within 0.3 digits. Further, ten conductive rollers 1 were manufactured and the variation in electric resistance was evaluated (normal condition: 23 ° C., humidity 50%), but the variation was within 0.1 digit.
[0046]
Further, the electric resistance of the conductive roller 1 was measured under the conditions of a temperature of 15 ° C. and a humidity of 10% (low temperature and low humidity), and a temperature of 33 ° C. and a humidity of 85% (high temperature and high humidity) (after being left for 2 to 5 hours under each condition). ) Was 3.0 × 10 ⁸ Ω and 6.0 × 10 ⁷ Ω, respectively, and the fluctuation of the electric resistance was 0.7 digits.
[0047]
(Example 2)
The resistance adjusting inner layer 4a was formed in the same manner as in Example 1, except that an aqueous urethane acrylic resin (KWP1000, manufactured by Kawakami Paint Co., Ltd.) was used instead of N-methoxymethylated nylon.
[0048]
The obtained conductive roller 1 has no irregularities such as bubbles on the surface, has an electric resistance of 8.0 × 10 ⁷ Ω, and has a variation in the electrical resistance in the circumferential direction of 0.3 digits. Was 0.2 digits, and the electrical resistances at low temperature, low humidity and high temperature and high humidity were 2.0 × 10 ⁸ Ω and 5.0 × 10 ⁷ Ω, respectively, and the fluctuation was 0.7 digits.
[0049]
(Comparative example)
The resistance adjusting layer 4 is prepared by dissolving a polycarbonate polyurethane resin in 400 parts by weight of a mixed solvent of MEK / DMF (weight mixing ratio: 50/50), adding 3 parts by weight of carbon black, stirring and dispersing the coating liquid to a thickness of 50 μm in a single layer. Except having formed in this way, it carried out similarly to Example 1.
[0050]
In the obtained conductive roller 1, bubbles were observed on the outer peripheral surface, which indicates that the conductive elastic layer 3 was swollen by the solvent. The electric resistance of the conductive roller 1 in the normal state is 1.5 × 10 ⁸ Ω, and the variation in the circumferential direction is 1.5 digits, and the electric resistance of 10 rollers is 1.0 × 10 ⁷ Ω to 5.0 ×. The variation of 10 ⁸ Ω was larger than one digit, which was a problem in practical use.
[0051]
【The invention's effect】
As described above, according to the present invention, a resistance adjustment layer is provided on the outer peripheral surface of a conductive elastic layer based on epichlorohydrin rubber, and the resistance adjustment layer is formed of at least an inner layer made of a hydrophilic resin and a hydrophobic resin. By forming the conductive roller as a multilayer structure with the outer layer, the electric resistance can be controlled to have a small variation in the range of 10 ⁶ to 10 ⁸ Ω, and the fluctuation of the electric resistance is small even with environmental changes such as temperature and humidity. In addition, it is possible to provide a conductive roller for an electrophotographic apparatus free from defects in appearance due to bubbles and the like, and a method for manufacturing the same.
[Brief description of the drawings]
FIG. 1 is a perspective view of a conductive roller 1 according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view perpendicular to the axis of the conductive roller 1 of FIG.
FIG. 3 is a cross-sectional view showing a part of a laser printer 5 which is an electrophotographic apparatus including the conductive roller 1 of FIG.
FIG. 4 is a cross-sectional view for explaining a step of forming a conductive elastic layer 3 of the conductive roller 1.
FIG. 5 is a cross-sectional view for explaining a step of forming a resistance adjusting layer 4 on the conductive elastic layer 3 of the conductive roller 1.
FIG. 6 is a conceptual diagram showing a method for measuring the electric resistance value of the conductive roller 1.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 conductive roll, charging roll 2 shaft 3 conductive elastic layer 4 resistance adjusting layer 4 a inner layer 4 b outer layer 5 laser printer 6 photoconductor 7 charging roller 12 developing device 13 developing roller 17 transfer rollers 21, 28 residual toner

Claims (3)

A conductive elastic layer having a volume resistivity of 10 ⁶ to 10 ¹⁰ Ω · cm by vulcanizing a rubber composition obtained by kneading a compounding agent containing a conductive filler with epichlorohydrin rubber on the outer peripheral surface of the conductive shaft. Forming a;
An inner layer having a thickness of 1 μm or more and 20 μm or less of a resistance adjusting layer is formed on the outer peripheral surface of the conductive elastic layer using a coating liquid in which N-methoxymethylated nylon is dissolved or dispersed in an alcohol or aqueous solvent. Process and
In at least one or more solvents selected from the group consisting of methyl ethyl ketone, dimethylformamide and toluene, at least one or more hydrophobic resins selected from the group consisting of polyester polyurethane resins, polycarbonate polyurethane resins and silicone polyurethane resins are dissolved or Forming an outer layer having a thickness of 0.5 μm or more and 100 μm or less on the outer peripheral surface of the inner layer of the resistance adjusting layer using the dispersed coating liquid. Roller manufacturing method. A conductive elastic layer having a volume resistivity of 10 ⁶ to 10 ¹⁰ Ω · cm by vulcanizing a rubber composition obtained by kneading a compounding agent containing a conductive filler with epichlorohydrin rubber on the outer peripheral surface of the conductive shaft. Forming a;
Forming an inner layer having a thickness of 1 μm or more and 20 μm or less on the outer peripheral surface of the conductive elastic layer using a coating liquid in which an aqueous urethane acrylic resin is dissolved or dispersed in an alcohol-based or aqueous solvent; ,
In at least one or more solvents selected from the group consisting of methyl ethyl ketone, dimethylformamide and toluene, at least one or more hydrophobic resins selected from the group consisting of polyester polyurethane resins, polycarbonate polyurethane resins and silicone polyurethane resins are dissolved or Forming an outer layer having a thickness of 0.5 μm or more and 100 μm or less on the outer peripheral surface of the inner layer of the resistance adjusting layer by using the dispersed coating liquid. Roller manufacturing method. The inner layer has a volume specific resistance value of 10 ¹⁰ Ω · cm,
The method according to claim 1, wherein the outer layer has a volume resistivity of 10 ¹¹ Ω · cm.

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