JP2007181953A - Conductive member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conductive member which can electrify an object to be electrified uniformly and sufficiently even when only dc voltage is applied and a pre-exposure means is not provided, controls the occurrence of a defective image such as a ghost image, is reduced in photosensitive body contamination when used for a long time, and is useful as an electrification roller. <P>SOLUTION: In the conductive member having a substrate good in conductivity and a semiconductor layer which is formed on the outside of the substrate and has at least one layer, the semiconductor layer contains an inorganic filler and a conductive filler having a surfactant layer with the surface of the inorganic filler coated with a surfactant and an organic conductive agent layer with the surfactant layer coated with an organic conductive agent having two specified repeating units. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a conductive member used in contact with a photoreceptor in an electrophotographic apparatus.

  In the following, details of the charging roller will be described as an example of the conductive member, but the present invention is not limited to the charging roller.

  In recent years, as a means for charging the surface of an image carrier (charged body) such as a photoreceptor or a dielectric in an image forming apparatus such as an electrophotographic apparatus such as a copying machine or an optical printer, or an electrostatic recording apparatus, a contact charging method is used. Is adopted. In the contact charging method, a charged member surface (also referred to as a charging member) that is charged with voltage is brought close to or in contact with the surface of the charged body, and the surface of the charged body is charged. As the charging member, a rubber roller type charging roller in which a semiconductive elastic layer is formed on a shaft of a metal core is generally used.

The elastic layer of the charging roller used in the contact charging method needs to have an appropriate semiconductivity in order to prevent leakage caused by pinholes or scratches on the surface of a charged body such as a photoreceptor. In addition, in order to uniformly charge the object to be charged, it is important that the electric resistance value of the charging member is a uniform semiconductivity having a volume resistivity of about 1 × 10 ³ to 1 × 10 ⁹ Ω · cm. It is. In order to realize such electrical characteristics, an elastic body layer has been conventionally produced using an electronically conductive semiconductive rubber composition in which conductive particles such as carbon black are mixed and made semiconductive. .

In such an electronic conductive rubber composition, the electrical resistance can be adjusted by the amount of conductive particles such as carbon black blended in the raw rubber. However, in the semiconductive region having a volume resistivity of 1 × 10 ³ to 1 × 10 ⁹ Ω · cm, the electrical resistance may change greatly due to a slight change in the blending amount of the conductive particles. There is a problem that it is difficult to produce an elastic body layer having a uniform desired electric resistance value in the semiconductive region, and variations in electric resistance are likely to occur within and between the charging members.

  As a technique for obtaining a rubber composition having a uniform electric resistance, a method using a polar rubber which itself has semiconductivity such as epichlorohydrin rubber or NBR is known. Alternatively, a method is known in which an elastic layer is formed from an ion conductive rubber composition such as adding an ionic conductive agent to a raw rubber to impart semiconductivity.

  Conventionally, a so-called “AC / DC charging method” has been used in the contact charging method (see, for example, Patent Document 1). The “AC / DC charging method” is an AC voltage component (AC voltage) having a peak-to-peak voltage more than twice the charging start threshold (Vth) in a DC voltage (DC voltage) corresponding to a desired surface potential Vd to be charged. This is a method in which a voltage on which a component) is superimposed is applied to the contact charging member. This is because the potential of the object to be charged converges to the potential Vd which is the center of the peak of the AC voltage due to the leveling effect of the AC voltage, and charging is not affected by external conditions such as the environment. Contact charging method.

  However, in the method disclosed in Patent Document 1, a high-voltage AC voltage that is a peak-to-peak voltage more than twice the charging start voltage (Vth) when a DC voltage is applied is superimposed. This is necessary and increases the cost of the device itself. Furthermore, there has been a problem that the durability of the charging roller and the electrophotographic photosensitive member is reduced by consuming a large amount of alternating current. Therefore, recently, charging has been performed using only the DC voltage as the voltage applied to the charging roller.

Further, conventionally, pre-exposure means for removing residual charges on the surface of the electrophotographic photosensitive member after image transfer by pre-exposure means using an LED chip array, fuse lamp, halogen lamp, fluorescent lamp, etc. upstream of the charging process. Was established. However, in recent years, demands for miniaturization and cost reduction of electrophotographic apparatuses have increased, and there is a demand for image formation without using this pre-exposure means.
JP-A 63-149668 JP 2001-250421 A

  However, as described above, the following problems occur when only the DC voltage is applied to the charging roller to charge the charged body or when the pre-exposure operation is not performed. In other words, a potential difference (difference between VD1 and VD2) is generated between the surface potential of the photoreceptor to be charged and the saturation potential (dark part potential VD) after the first charging cycle and second charging cycle. End up. Then, for example, in the case of the reversal development method, if a halftone image is continuously output immediately after forming a latent image of a character or black figure, the character or black figure is slightly left behind on the halftone image. This causes a problem that the phenomenon (ghost image) appears remarkably.

  As means for solving the ghost image, it is known to lower the electric resistance of the charging roller and increase the charging ability. As a means to achieve low resistance by using an ion conductive rubber composition with uniform electrical resistance, a conductive material in which an ionic conductive agent such as a quaternary ammonium salt is blended with a polar rubber such as epichlorohydrin rubber is proposed. (For example, refer to Patent Document 2).

  However, when a large amount of ionic conductive agent is blended and the electrical resistance is set low, the ionic conductive agent may contaminate the photoconductor, resulting in functional failure of the photoconductor, and image defects may occur during long-term use. It was.

  The present invention can apply a direct current voltage only, and even without a pre-exposure means, the object to be charged can be uniformly and sufficiently charged, and image defects such as ghost images are unlikely to occur. An object of the present invention is to provide a conductive member suitable for a charging roller with a small amount of charge.

  As a result of intensive studies on the above problems, the inventor of the present application uses a conductive filler having a specific configuration, and adjusts the electric resistance of the elastic layer, thereby preventing the photosensitive member from being contaminated and having a low electric resistance. I found out that The conductive filler was obtained by coating the surface of an inorganic filler with a surfactant and coating the surfactant with an organic conductive agent.

That is, the present invention is as follows.
(1) In a conductive member having a highly conductive base material and a semiconductive layer comprising at least one layer provided on the outside thereof, the semiconductive layer is
An inorganic filler, a surfactant layer having a surface coated with a surfactant, a repeating unit represented by the following general formula (I) and the following general formula (II) on the surfactant layer An organic conductive agent layer coated with an organic conductive agent having the repeating unit shown, and a conductive filler,
It is an electroconductive member characterized by containing.

(Wherein n represents an integer of 10 or more, R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group or an alkyl-substituted phenyl group)

(In the formula, R3 represents a hydrogen atom or a methyl group, Q represents a divalent linking group, A represents a sulfonic acid group, a phosphoric acid group, a carboxylic acid group, or a group in which these acid groups have been neutralized. )
(2) The conductive member according to (1), wherein the inorganic filler is calcium carbonate.
(3) The conductive member according to (1) or (2), wherein the organic conductive agent layer further contains a lithium salt.

  According to the present invention, even if only a DC voltage is applied and the pre-exposure means is not provided, it has the ability to uniformly and sufficiently charge the object to be charged, and an image such as a ghost image, density unevenness, photoreceptor contamination, etc. A conductive member suitable as a charging roller with few defects can be provided.

  Hereinafter, the present invention will be described in more detail.

  FIG. 2 shows a schematic configuration of an electrophotographic apparatus having the conductive member of the present invention. Reference numeral 21 denotes an electrophotographic photosensitive member as a member to be charged. The electrophotographic photosensitive member of this example is basically composed of a conductive support 21b such as aluminum and a photosensitive layer 21a formed on the conductive support 21b. A drum-shaped electrophotographic photosensitive member. The electrophotographic photosensitive member 21 is rotationally driven around the support shaft 21c in the clockwise direction in the figure at a predetermined peripheral speed.

  Reference numeral 1 denotes a conductive member of the present invention, which is a charging roller that is placed in contact with the electrophotographic photosensitive member 21 and charges (primary charging) the electrophotographic photosensitive member to a predetermined polarity and potential. The charging roller 1 includes a cored bar 11, an elastic body layer 12 formed on the cored bar 11, and a surface layer 13 formed on the elastic body layer 12, and both ends of the cored bar 11 are pressed by unillustrated pressing means. As the electrophotographic photosensitive member 21 is rotated, it is driven to rotate.

  The electrophotographic photosensitive member 21 is brought into contact with the charging roller 1 to which a predetermined direct current (DC) bias is applied to the core metal 11 by the rubbing power source 23 a connected to the power source 23. Contact charged to a predetermined polarity and potential.

  The electrophotographic photosensitive member 21 whose peripheral surface is charged by the charging roller 1 is then subjected to exposure of target image information (laser beam scanning exposure, slit exposure of a document image, etc.) by the exposure means 24, so that the peripheral surface has a target. An electrostatic latent image corresponding to the image information is formed.

  The electrostatic latent image is then successively visualized as a toner image by the developing means 25. This toner image is then synchronized with the rotation of the electrophotographic photosensitive member 21 from a paper feeding unit (not shown) by the transfer unit 26 and transferred at a proper timing between the electrophotographic photosensitive member 21 and the transfer unit 26. Are sequentially transferred to the transfer material 27 conveyed to the substrate. The transfer means 26 of this example is a transfer roller, and the toner image on the electrophotographic photosensitive member 21 side is transferred to the transfer material 27 by charging from the back of the transfer material 27 with the opposite polarity to the toner.

  The transfer material 27 having received the transfer of the toner image on the surface is separated from the electrophotographic photosensitive member 21 and conveyed to a fixing means (not shown) to receive image fixing and output as an image formed product. Alternatively, in the case of forming an image on the back side, it is conveyed to a re-conveying means to the transfer unit.

  The peripheral surface of the electrophotographic photosensitive member 21 after the image transfer is subjected to pre-exposure by the pre-exposure means 28, and residual charges on the electrophotographic photosensitive drum are removed (static elimination). Known means can be used for the pre-exposure means 28. For example, an LED chip array, a fuse lamp, a halogen lamp, and a fluorescent lamp can be preferably exemplified. In addition, a configuration without the pre-exposure means can be adopted.

  The peripheral surface of the electrophotographic photosensitive member 21 that has been neutralized is cleaned by the cleaning means 29 to remove adhering contaminants such as untransferred toner, and is repeatedly used for image formation.

  The charging roller 1 may be driven by the electrophotographic photosensitive member 21 that is driven to move on the surface, may not be rotated, or is predetermined in the forward or reverse direction in the surface moving direction of the electrophotographic photosensitive member 21. It is also possible to positively drive the rotation at a peripheral speed.

  In the case of a copying machine, exposure is performed by reflecting or transmitting light from a document, or by reading a document as a read signal, scanning a laser beam based on this signal, driving an LED array, or a liquid crystal shutter array. It is performed by driving.

  Examples of the electrophotographic apparatus that can use the conductive member of the present invention include copying machines, laser beam printers, LED printers, and electrophotographic application apparatuses such as an electrophotographic plate making system.

  In addition to a charging member such as a charging roller, the conductive member of the present invention can be used as a developing member, a transfer member, a charge eliminating member, or a conveying member such as a paper feed roller.

  The conductive member of the present invention is composed of a highly conductive base material and a semiconductive layer composed of at least one layer provided on the outside thereof. FIG. 1 is a schematic cross-sectional view of a charging roller as an example of the conductive member of the present invention. This charging roller is composed of a core metal 11 as a base material, an elastic layer 12 as a semiconductive layer provided on the outer periphery thereof, and a surface layer 13 provided outside the elastic layer 12. Yes.

The elastic layer is a semiconductive region having a volume resistivity of 1 × 10 ³ to 1 × 10 ⁹ Ω · cm, and the volume resistivity measured in an environment of 23 ° C. and 50% RH is 1 in particular. × 10 ⁷ Ω · cm or less is preferable. When the volume resistivity is more than 1 × 10 ⁷ Ω · cm, the charging ability of the photoreceptor surface may be insufficient. In other words, in an electrophotographic process without pre-exposure, the charge potential difference on the surface of the photoreceptor after passing through the transfer process may not be able to be made a uniform surface potential by the charging process, and a ghost image may be generated. is there.

As a specific means for setting the electric resistance of the elastic layer to 1 × 10 ⁷ Ω · cm or less, the surface of the inorganic filler is coated with a surfactant and the surfactant is coated with an organic conductive agent. A functional filler is blended.

  FIG. 3 shows a schematic cross-sectional view of the conductive filler used in the present invention. The conductive filler includes a surfactant layer 32 coated with a surfactant on the surface of an inorganic filler 31 serving as a core, and an organic conductive agent layer 33 coated with an organic conductive agent on the surfactant layer 32. Have. The surfactant layer 32 coated on the surface of the inorganic filler 31 does not necessarily have to completely cover the surface of the inorganic filler, and there may be a portion that is not partially covered. The organic conductive agent layer 33 coated on the surfactant layer 32 does not necessarily have to completely cover the surface of the surfactant layer 32, and there may be a portion that is not partially covered. .

  Examples of the inorganic filler include various inorganic substances such as heavy calcium carbonate, light calcium carbonate, talc, sericite, calcium sulfate, montmorillonite, zeolite, calcium sulfite, aluminum hydroxide, aluminum oxide, zinc oxide, barium sulfate, and kaolin. One kind or a mixture of two or more kinds may be mentioned. It is preferable to select an inorganic filler having an average particle size of 0.1 to 20 μm.

  Examples of the surfactant coated on the surface of the inorganic filler include primary, secondary and tertiary amine salt type cationic low molecular or high molecular surfactants, and quaternary ammonium salt type cationic low molecular or high molecular surfactants. An activator is mentioned. Examples of the primary to tertiary amine salt type low molecular surfactant include higher alkylamine salts, higher alkylamine ethylene oxide adducts, higher alkylamine ethylene oxide / propylene oxide adducts, solomine A type amine salts, and sapamin A type. Examples thereof include amine salts, archebel A-type amine salts and imidazoline-type amine salts. Examples of the quaternary ammonium salt type low molecular surfactant include higher alkyltrimethylammonium salt, alkyldimethylbenzylammonium salt, sapamin type quaternary ammonium salt, imidazoline type quaternary ammonium salt and alkylbiridium salt. It is done. Examples of the primary to tertiary amine salt type polymer surfactant include polyethyleneimine, polyalkylene polyamine salt, polyamine / dicyandiamide condensation salt, polydiallylamine salt, etc., and quaternary ammonium salt type polymer surfactant. Examples thereof include polystyrene methylaminotrimethylammonium salt, polydiallyldimethylammonium salt, trimethylaminoethyl (meth) acrylate ammonium salt, and poly N-alkylpyridine salt. Among these cationic surfactants, for example, when calcium carbonate is used as a filler, an amine salt type polymer surfactant or a quaternary ammonium salt type polymer surfactant is used to obtain a high-concentration slurry during wet grinding. Agents are preferred. Particularly preferred are salts of diallylamine alone or copolymers with vinyl compounds and polydiallyldimethylammonium salts.

  The method for coating the surface of the inorganic filler with these surfactants is not particularly limited, and it can be achieved by wet-grinding the inorganic filler in the presence of the surfactant.

  Specifically, the aqueous medium is added to the inorganic filler so that the mass ratio of the inorganic filler / aqueous medium (preferably water) is in the range of 70/30 to 30/70, preferably 60/40 to 40/60. . Here, the surfactant is added as a solid content in an amount of 0.01 to 5 parts by mass, preferably 0.01 to 0.7 parts by mass, per 100 parts by mass of the inorganic filler, and wet pulverized by a conventional method. Alternatively, an aqueous medium in which a surfactant in an amount in the above range is dissolved in advance is mixed with an inorganic filler, and wet pulverized by a conventional method. The wet pulverization may be a batch type or a continuous type, and it is preferable to use a mill using a pulverization medium such as a sand mill, an attritor, or a ball mill.

  It is preferable that the surfactant and the inorganic filler form a chemical bond. By forming a chemical bond between the surfactant and the inorganic filler, the surfactant is fixed to the inorganic filler and is prevented from contaminating the photoreceptor. A combination of a cationic copolymer comprising a diallylamine salt and / or an alkyldiallylamine salt and a nonionic vinyl monomer as a surfactant as a surfactant and calcium carbonate as an inorganic filler is preferred. Further, when the surfactant is coated on the surface of the inorganic filler by wet pulverization, heavy calcium carbonate is most preferable as the inorganic filler.

  The ratio of the surfactant and the inorganic filler contained in the finally obtained conductive filler is preferably such that the surfactant is in the range of 0.01 to 5 parts by mass with respect to 100 parts by mass of the inorganic filler. .

  The surface of the inorganic filler coated with the surfactant is further coated with an organic conductive agent having a repeating unit represented by the general formula (I) and a repeating unit represented by the general formula (II).

(Wherein n represents an integer of 10 or more, R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group or an alkyl-substituted phenyl group)

(In the formula, R3 represents a hydrogen atom or a methyl group, Q represents a divalent linking group, A represents a sulfonic acid group, a phosphoric acid group, a carboxylic acid group, or a group in which these acid groups have been neutralized. )
As the organic conductive agent, a copolymer obtained by copolymerizing a monomer that gives a repeating unit represented by the general formula (I) and a monomer that gives a repeating unit represented by the general formula (II) should be used. Can do.

  Preferable examples of the monomer that gives the repeating unit represented by formula (I) include the following. That is, the terminal portion of poly (or oligo) ethylene glycol having an alkyl group or alkyl-substituted phenyl group at one end and an ethyleneoxy group having a polymerization degree of 10 or more is esterified with a methacryloyl group or an acryloyl group. . For this purpose, methacrylic acid or acrylic acid is particularly preferably used. As the alkyl group for R2, a linear or branched alkyl group having 1 to 25 carbon atoms is preferable because it exhibits good miscibility with a polymer material such as rubber to be blended. N of the number of ethyleneoxy groups is 10 or more, and the range of 12-50 is preferable. If it is less than 10, the conductivity is small, which is not preferable. On the other hand, when it is 50 or more, the affinity with the base polymer is lowered, which is not preferable.

  In the copolymer, the proportion of the repeating unit represented by formula (I) is preferably in the range of 10% by mass to 99% by mass, and more preferably in the range of 50% by mass to 99% by mass. When the composition ratio of the general formula (I) is small, the conductivity as the conductive filler is small, which is not preferable.

  In the general formula (II), the divalent linking group represented by Q is not particularly limited, and any linking group can be used as long as it is a group linking A which is an acid group and a radically polymerizable double bond. This is included. Examples thereof include a sulfonic acid group, a phosphoric acid group, and a carboxylic acid group. Examples of preferred monomers of the general formula (II) include styrene sulfonic acid, vinyl sulfonic acid, allyl sulfonic acid, methallyl sulfonic acid, acrylamidomethylpropane sulfonic acid and salts thereof as a monomer having a sulfonic acid group; A monomer having acid phosphooxyethyl methacrylate, acid phosphooxypropyl methacrylate, 3-chloro-2-acid phosphooxypropyl methacrylate, acid phosphooxypolyethylene glycol monomethacrylate, acid phosphooxypolypropylene glycol monomethacrylate and salts thereof; As monomers having a carboxylic acid group, acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, maleic anhydride and salts thereof And the like.

  The “group in which these acid groups are neutralized” in A of the general formula (II) is a group in which these acid groups are neutralized with an alkali metal, an alkaline earth metal, ammonia, an amine, or the like. The neutralized form is more conductive than the free acid form.

  In the above copolymer, the proportion of the repeating unit represented by the general formula (II) is preferably 90% by mass or less, because the dispersibility when kneaded into rubber or the like is good, is preferably 50% by mass. % Or less is more preferable. Further, A which is an acid group of the general formula (II) is fixed on the surface of the conductive filler by ionic bonding with a cation group such as an amine group of a surfactant coated on the inorganic filler. Therefore, the proportion of the repeating unit represented by the general formula (II) is preferably 1% by mass or more.

  As the organic conductive agent, in addition to the monomers of the above general formula (I) and general formula (II), a copolymer using another copolymerizable monomer as a copolymerization monomer can also be used. For example, styrene derivatives such as styrene, 4-methylstyrene, 4-hydroxystyrene, 4-carboxystyrene, 4-aminostyrene, chloromethylstyrene, 4-methoxystyrene; methyl (meth) acrylate, ethyl (meth) acrylate (Meth) acrylic acid alkyl esters such as (meth) acrylic acid butyl, (meth) acrylic acid hexyl, (meth) acrylic acid 2-ethylhexyl, (meth) acrylic acid cyclohexyl, (meth) acrylic acid dodecyl; ) (Meth) acrylic acid aryl esters or aralkyl esters such as phenyl acrylate and benzyl (meth) acrylate; amino groups such as (meth) acrylic acid 2-dimethylaminoethyl and (meth) acrylic acid 2-diethylaminoethyl (Meth) acrylic acid esters; -Monomers having a quaternary ammonium base such as vinylbenzyltrimethylammonium chloride; amino group-containing monomers such as allylamine and diallylamine; 4-vinylpyridine, 2-vinylpyridine, N-vinylimidazole, N-vinylcarbazole, etc. Monomers having a nitrogen-containing heterocycle; acrylonitrile, methacrylonitrile; acrylamide or methacryl such as acrylamide, methacrylamide, dimethylacrylamide, diethylacrylamide, N-isopropylacrylamide, diacetoneacrylamide, N-methylolacrylamide, N-methoxyethylacrylamide Amide derivatives; vinyl acetate, vinyl chloroacetate, vinyl propionate, vinyl butyrate, vinyl stearate, vinyl benzoate, etc. Various esters such as vinyl esters such as methyl vinyl ether and butyl vinyl ether; various monomers such as N-vinylpyrrolidone, acryloylmorpholine, tetrahydrofurfuryl methacrylate, vinyl chloride, vinylidene chloride, allyl alcohol, vinyltrimethoxysilane, and glycidyl methacrylate; It can be used as a monomer.

  In the case where such other copolymerizable monomers are further introduced into the polymer, the units formed by these monomers are preferably 50% by mass or less in the copolymer. If it is introduced in a proportion exceeding 50% by mass, the conductivity may be impaired, which is not preferable.

  Further, the copolymer having both the repeating units of the general formula (I) and the general formula (II), at least one salt selected from the group consisting of an alkali metal salt and an alkaline earth metal salt, particularly a sodium salt, It is preferable to add potassium salt or lithium salt. Particularly preferred salts are lithium salts, which can take the form of chlorides, sulfates, acetates, phosphates, carbonates, perchlorates, trifluoromethanesulfonates, and the like. These salts are preferably added to the copolymer in a form dissolved in water or other suitable solvent, and several oxyethylene units and ions in the repeating unit represented by the general formula (I) in the copolymer Complexes can be formed and good conductivity can be imparted.

  The ratio of the copolymer to the salt is preferably in the range of 5 to 100 parts by mass of the salt with respect to 100 parts by mass in the copolymer.

Examples of the method of coating the surface of the inorganic filler coated with the surfactant (surfactant-treated inorganic filler) with the organic conductive agent include the following methods.
(1) In the wet pulverization step for coating the surfactant, a surfactant is treated by adding a liquid in which a copolymer that is an organic conductive agent is dispersed in advance, and drying after wet pulverization. A method of coating the surface of an inorganic filler with an organic conductive agent.
(2) A method of adding a copolymer serving as an organic conductive agent to a dispersion of a surfactant-treated inorganic filler that has been wet pulverized or dispersed, and then drying.
(3) A method in which a surfactant-treated inorganic filler dried after wet pulverization is surface-coated with a copolymer serving as an organic conductive agent by a method such as spray coating.

  In addition, when adding a salt such as a lithium salt, whether a salt such as a lithium salt is added to the copolymer in advance, or a salt such as a lithium salt is added to a conductive filler coated with the copolymer. Any of these may be used.

  For example, when the surface is coated with the organic conductive agent by the method (2), it can be performed as follows. An organic conductive agent is added to the dispersion of the wet-ground surfactant-treated inorganic filler, and mixed and stirred. When salts such as lithium salts are added together, a mixture of an organic conductive agent and salts is prepared in advance, and the mixture may be added. The ratio of the copolymer as the organic conductive agent used at this time and the inorganic filler is preferably in the range of 0.5 to 10 parts by mass of the organic conductive agent with respect to 100 parts by mass of the inorganic filler. Thereafter, the conductive filler can be obtained by drying using a medium fluidized dryer or the like.

  The ratio of the organic conductive agent and the inorganic filler contained in the finally obtained conductive filler is preferably such that the organic conductive agent is in the range of 0.5 to 10 parts by mass with respect to 100 parts by mass of the inorganic filler. .

  The elastic body layer of the conductive member contains the conductive filler having the above-described configuration, and the composition thereof is adjusted so as to have physical properties necessary for the conductive member. For example, the elastic body layer can be formed from a rubber composition containing a raw rubber and a conductive filler.

  The raw material rubber for the elastic layer is not particularly limited, but a polar rubber having a low electric resistance is preferable. Preferred polar rubbers include epichlorohydrin homopolymer (CHC), epichlorohydrin-ethylene oxide copolymer (CHR), epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer (CHR-AGE), acrylonitrile-butadiene copolymer ( NBR), hydrogenated acrylonitrile-butadiene copolymer (H-NBR), acrylic rubber (ACM, ANM), and urethane rubber (U). The raw rubber may be used alone or as a blend of two or more.

  The composition of the rubber composition that forms the elastic layer is preferably in the range of 5 to 300 parts by mass of the conductive filler with respect to 100 parts by mass of the raw rubber.

  The elastic layer can contain a small amount of an ionic conductive agent so as not to contaminate the photoreceptor. Examples of the ionic conductive agent include inorganic ionic substances such as lithium perchlorate, sodium perchlorate, and calcium perchlorate; lauryl trimethyl ammonium chloride, stearyl trimethyl ammonium chloride, octadecyl trimethyl ammonium chloride, dodecyl trimethyl ammonium chloride, hexadecyl Cationic surfactants such as trimethylammonium chloride, trioctylpropylammonium bromide, modified aliphatic dimethylethylammonium ethosulphate; amphoteric surfactants such as lauryl betaine, stearyl betaine, dimethylalkyl lauryl betaine; tetraethyl perchlorate Ammonium, tetrabutylammonium perchlorate, trimethyloctadecylammonium perchlorate, etc. Grade Ammonium perchlorate; organic lithium salt such as lithium trifluoromethane sulfonate; and the like.

  When the ionic conductive agent is used, the amount of the ionic conductive agent is preferably not more than 2 parts by mass with respect to 100 parts by mass of the raw rubber. When the blending amount of the ionic conductive agent is more than 2 parts by mass, there is a possibility that the photoreceptor is contaminated.

  Furthermore, for the elastic layer, a filler, a softening agent, a processing aid, a crosslinking aid, a crosslinking accelerator, a crosslinking accelerator, a crosslinking retarder, an adhesive, which are generally used as a rubber compounding agent, if necessary. An imparting agent, a dispersing agent, or the like can be added.

  Examples of a method for mixing the raw materials of these rubber compositions include a mixing method using a closed mixer such as a Banbury mixer and a pressure kneader, and a mixing method using an open mixer such as an open roll. can do.

  In the charging roller of this example, a surface layer can be provided on the outer periphery of the elastic layer. The surface layer may be a single layer or a plurality of layers of two or more layers. The surface layer preferably has a higher electrical resistance than the elastic layer. Leakage caused by pinholes or scratches on the surface of the photoreceptor can be prevented by using a multilayer structure of two or more layers and increasing the electrical resistance on the surface side.

The electrical resistance value of the surface layer is usually required to be about 1 × 10 ⁶ to 1 × 10 ¹⁰ Ω. Generally, the desired electrical resistance value is obtained by dispersing an appropriate amount of a conductive substance in a binder polymer. Used. As the binder polymer, acrylic, polyurethane, polyamide, polyester, polyolefin, silicone, or the like is used. Examples of the conductive substance include oxides such as carbon black, graphite, titanium oxide, and tin oxide; metals such as Cu and Ag; conductive particles obtained by coating the surface of the particles with oxides and metals; LiClO ₄ , KSCN, An ionic electrolyte such as NaSCN or LiCF ₃ SO ₃ is used.

  The surface layer can be formed by dissolving or dispersing the binder polymer as described above in a solvent and dispersing a conductive material in the solvent by a coating method such as dipping, beam coating, roll coater, or spraying. And a method of coating the surface of the elastic layer.

  The charging roller according to the present invention may be provided with functional layers such as an adhesive layer, a diffusion prevention layer, a base layer, and a primer layer in addition to the elastic layer and the surface layer as necessary.

  The present invention will be described in more detail with reference to the following examples, but these examples do not limit the present invention. Hereinafter, “parts” means “parts by mass” unless otherwise specified.

(Preparation of conductive filler 1)
2,2-azobis (2-amidinopropane) dihydrochloride as a polymerization initiator was added to a mixture of diallylamine hydrochloride (60% by mass) and acrylamide (40% by mass) as a polymerization initiator in a nitrogen atmosphere with stirring. Acetone was added to the obtained reaction product and washed to obtain a cationic surfactant.

  Next, methoxy polyethylene glycol methacrylate (n = 23, chemical formula (3)) and acid phosphoxyethyl methacrylate (chemical formula (4)) were polymerized at a mass ratio of 80:20 to obtain an organic conductive agent.

  Heavy calcium carbonate having an average particle size of 30 μm and water were mixed so that the mass ratio was 40/60. Here, 0.06 part of the cationic surfactant produced as described above was added to 100 parts of heavy calcium carbonate, and the mixture was made into a wet pulverized slurry using a stirring mill. The agent was coated. Next, the organic conductive agent synthesized as described above was mixed and stirred in this slurry at a ratio of 2 parts to 100 parts of heavy calcium carbonate, and dried with a medium fluidized dryer (organic conductive agent coating step). And the surface of the heavy calcium carbonate was coat | covered with surfactant, and the conductive filler 1 by which the surface of the surfactant was coated with the organic electrically conductive agent was obtained.

(Preparation of conductive filler 2)
An amount of 0.5 part of lithium perchlorate per 100 parts of heavy calcium carbonate was previously mixed with an organic conductive agent to prepare a mixture. In the organic conductive agent coating step, a conductive filler 2 was obtained by the same method as the production of the conductive filler 1 except that the mixture was added.

(Example 1: Charging roller 1)
The components shown below were mixed with a pressure kneader to obtain an A-kneaded rubber composition.
・ Raw material rubber (hydrin rubber A, epichromer CG-102; trade name, manufactured by Daiso)
100 parts ・ Processing aid (zinc stearate) 1 part ・ Vulcanization accelerator (zinc oxide) 5 parts ・ Filler (MT carbon black, MT-CB; Thermax Flow Foam N990; trade name manufactured by Cancarb) 5 Part / plasticizer (polyester plasticizer, plasticizer-1; molecular weight 8000)
5 parts / 50 parts of the conductive filler 1 described above With respect to 166 parts by mass of this A-kneaded rubber composition, the following components were mixed in an open roll to obtain an unvulcanized rubber composition.
・ Crosslinking agent (sulfur) 0.5 part ・ Vulcanization accelerator (N-cyclohexylbenzothiazole-2-sulfenamide, CBS; Noxeller CZ; trade name, manufactured by Ouchi Shinko Chemical Co., Ltd.) 1 part The vulcanized rubber composition was subjected to press vulcanization at 160 ° C. for 30 minutes in a sheet molding die having a thickness of 2 mm, then taken out from the die and subjected to secondary vulcanization at 160 ° C. for 2 hours in a hot air oven, A molded sheet was obtained. Using this molded sheet, the volume resistivity of a rubber material to be an elastic body layer was measured. The measurement was performed at an applied voltage of 100 V in an environment of 23 ° C. and 50% RH in accordance with a standard of the Japan Rubber Association “Method of measuring volume resistivity of rubber and rubber-like analogue SRIS-2304”. As a result, the volume resistivity of this rubber material was 9.2 × 10 ⁶ Ω · cm.

  The obtained unvulcanized rubber composition was extruded into a tube shape by a vent type rubber extruder (φ50 mm vent extruder; L / D = 16; manufactured by EM Giken Co., Ltd.), and 160 ° C. 30 by pressurized steam using a vulcanized can. The primary vulcanization was performed. A rubber tube having an outer diameter of 15 mm, an inner diameter of 5.5 mm, and a length of 250 mm was obtained.

  Next, a conductive vulcanizing adhesive (Metaloc U-20; Toyo Chemical Co., Ltd.) is attached to the central portion 232 mm in the axial direction of a cylindrical surface of a cylindrical conductive core (steel, surface is nickel-plated) having a diameter of 6 mm and a length of 252 mm. (Laboratory product name) was applied and dried at 80 ° C. for 30 minutes. The above-mentioned rubber tube was press-fitted into this conductive metal core, followed by secondary vulcanization and adhesion treatment at 160 ° C. for 2 hours in a hot air furnace. After vulcanization, both ends of the rubber were cut off to make the length of the rubber part 232 mm, and then the rubber part was polished with a polishing machine (LEO-600-F4-BME; trade name manufactured by Mizuguchi Seisakusho). Then, a rubber roller 1 having a crown-shaped elastic body layer having an end diameter of 12.00 mm and a central diameter of 12.10 mm was obtained.

  FIG. 4 shows a schematic diagram of an apparatus for measuring the electrical resistance of a rubber roller. The rubber roller 4 a is brought into pressure contact with the cylindrical aluminum drum 41 by pressing means (not shown) at both ends of the core metal 11 and is driven to rotate as the aluminum drum 41 is driven to rotate. In this state, a DC voltage is applied to the cored bar portion 11 of the rubber roller 4a using the power source 42, and the electric resistance of the rubber roller 4a can be measured from the voltage applied to the resistor 43 connected in series to the 41 aluminum drum. . Further, the circumferential unevenness of the electrical resistance can be measured from the ratio between the maximum resistance and the minimum resistance.

  Therefore, temperature 23 ° C., humidity 50% R.D. H. Under the environment (also referred to as N / N), using the apparatus of FIG. 4, a voltage of DC 200V was applied between the metal core and the metal drum for 3 seconds, and the ratio of the maximum resistance to the minimum resistance The electrical resistance circumferential unevenness was measured. As a result, the circumferential unevenness of the electrical resistance of the rubber roller 1 was 1.1 times.

  A surface layer was formed on the elastic body layer of the rubber roller 1 by the following method.

  50 parts of conductive tin oxide powder (SN-100P; trade name, manufactured by Ishihara Sangyo Co., Ltd.), 500 parts of a 1% by mass isopropyl alcohol solution of trifluoropropyltrimethoxysilane and glass beads having an average particle diameter of 0.8 mm 300 parts were added. And after dispersion | distributing for 70 hours with a paint shaker, the dispersion liquid was filtered with the mesh of 500 mesh. Next, this solution was heated in a 100 ° C. hot water bath while stirring with a Nauta mixer, and the alcohol was blown off and dried. A silane coupling agent was applied to the surface to obtain a surface-treated conductive tin oxide powder.

  200 parts of lactone-modified acrylic polyol (Placcel DC2009; trade name, manufactured by Daicel Chemical Industries, Ltd., xylene solution of 70% by weight of polyol component) is dissolved in 500 parts of MIBK (methyl isobutyl ketone), and a solution having a polyol concentration of 20% by weight. It was. 60 parts of the surface-treated conductive tin oxide powder and 0.01 part of silicone oil (SH-28PA; trade name manufactured by Toray Dow Corning Silicone) are blended with 200 parts of this polyol solution, and the diameter is further increased. 200 parts of 0.8 mm glass beads were added. Then, the mixture was placed in a 450 ml bottle and dispersed for 10 hours using a paint shaker.

The following components were mixed with 380 parts of this dispersion, stirred for 1 hour with a ball mill, and finally filtered with a 500 mesh screen to obtain a coating material for forming a surface layer.
・ Isophorone diisocyanate block type isocyanurate type trimer (Vestanat B1370; trade name manufactured by Degussa Huls) 30.6 parts ・ Isocyanurate type trimer of hexamethylene diisocyanate (Duranate TPA-B80E; trade name manufactured by Asahi Kasei Kogyo 19.6 parts This surface layer-forming paint was applied to the elastic layer surface of the rubber roller 1 by the dipping method. After coating with a lifting speed of 320 mm / min and air-drying for 30 minutes, the axial direction at the time of roller application was reversed, and again with a lifting speed of 320 mm / min and air-dried for 30 minutes. And dried at 160 ° C. for 60 minutes. And the charging roller 1 was obtained.

  The charging roller 1 was installed in the electrophotographic apparatus shown in FIG. 2 (Laser Shot LBP-2510; trade name, manufactured by Canon Inc.) and image evaluation was performed. The image evaluation was performed under the following conditions so that the difference in charging ability by the charging roller was most noticeable. That is, in a low-temperature and low-humidity environment of a temperature of 15 ° C. and a humidity of 10% (also referred to as L / L), the image evaluation is performed only on the DC voltage on the core of the charging roller so that the photoreceptor surface potential is −500V. Was applied. The pre-exposure means in the electrophotographic process shown in FIG. 2 is not operated. As the evaluation image, a halftone image was formed after solid black printing, and the uniformity of the ghost image and the halftone was evaluated. As a result, no ghost was observed and the halftone uniformity was good.

  Next, the charging roller 1 is moved to 40 ° C. and 95% R.D. H. After being left for 30 days in this environment, it was once again incorporated into an electrophotographic apparatus, and a halftone image was formed in an NN environment, and image evaluation after being left in a harsh environment was performed. As a result, transfer of contaminants from the charging roller 1 to the photosensitive member was not confirmed, and an image with good quality was obtained.

(Example 2: Charging roller 2)
An unvulcanized rubber composition was obtained in the same manner as in Example 1 except that 0.5 part of an ionic conductive agent (tetrabutylammonium perchlorate) was added as a component of the kneaded rubber composition. About the obtained unvulcanized rubber composition, it shape | molded in the sheet form similarly to Example 1, and measured the volume resistivity of the rubber material used as an elastic body layer. As a result, the volume resistivity was 3.8 × 10 ⁶ Ω · cm.

  Next, using the unvulcanized rubber composition, a rubber roller 2 having an elastic layer on the outer periphery of the conductive metal core was molded in the same manner as in Example 1. Then, the circumferential unevenness of the electric resistance was measured. As a result, the circumferential unevenness of electric resistance was 1.1 times.

  A surface layer was coated on the elastic layer of the rubber roller 2 in the same manner as in Example 1 to obtain a charging roller 2. When this charging roller 2 was subjected to image evaluation in the same manner as in Example 1, no ghost was observed, and the halftone uniformity was good. Further, in the image evaluation after being left in a harsh environment, the transfer of contaminants from the charging roller 2 to the photosensitive member was not confirmed, and an image with good quality was obtained.

(Example 3: Charging roller 3)
An unvulcanized rubber composition was obtained in the same manner as in Example 1 except that hydrin rubber B (Epion 301; trade name, manufactured by Daiso Corporation) was used instead of hydrin rubber A used as a component of the kneaded rubber composition. It was. About the obtained unvulcanized rubber composition, it shape | molded in the sheet form similarly to Example 1, and measured the volume resistivity of the rubber material used as an elastic body layer. As a result, the volume resistivity was 6.4 × 10 ⁶ Ω · cm.

  Next, using the unvulcanized rubber composition, a rubber roller 3 having an elastic layer on the outer periphery of the conductive metal core was molded in the same manner as in Example 1. Then, the circumferential unevenness of the electric resistance was measured. As a result, the circumferential unevenness of electric resistance was 1.1 times.

  A surface layer was coated on the elastic layer of the rubber roller 3 in the same manner as in Example 1 to obtain the charging roller 3. When this charging roller 3 was subjected to image evaluation in the same manner as in Example 1, no ghost was observed and the halftone uniformity was good. Further, in the image evaluation after being left in a harsh environment, the transfer of contaminants from the charging roller 3 to the photosensitive member was not confirmed, and an image with good quality was obtained.

(Example 4: charging roller 4)
An unvulcanized rubber composition was obtained in the same manner as in Example 1 except that the conductive filler 2 was used instead of the conductive filler 1 used as a component of the kneaded rubber composition. About the obtained unvulcanized rubber composition, it shape | molded in the sheet form similarly to Example 1, and measured the volume resistivity of the rubber material used as an elastic body layer. As a result, the volume resistivity was 6.0 × 10 ⁶ Ω · cm.

  Next, using the unvulcanized rubber composition, a rubber roller 4 having an elastic layer on the outer periphery of the conductive metal core was molded in the same manner as in Example 1. Then, the circumferential unevenness of the electric resistance was measured. As a result, the circumferential unevenness of electric resistance was 1.2 times.

  A surface layer was coated on the elastic layer of the rubber roller 4 in the same manner as in Example 1 to obtain the charging roller 4. When this charging roller 4 was subjected to image evaluation in the same manner as in Example 1, no ghost was observed, and the halftone uniformity was good. Further, in the image evaluation after being left in a harsh environment, the transfer of contaminants from the charging roller 4 to the photosensitive member was not confirmed, and an image of good quality was obtained.

(Comparative Example 1: Charging roller 5)
The components shown below were mixed with a pressure kneader to obtain an A-kneaded rubber composition.
・ Raw material rubber (hydrin rubber A, epichromer CG-102; trade name, manufactured by Daiso)
100 parts ・ Processing aid (zinc stearate) 1 part ・ Vulcanization accelerator (zinc oxide) 5 parts ・ Filler (MT carbon black, MT-CB; Thermax Flow Foam N990; trade name manufactured by Cancarb) 5 Part / plasticizer (polyester plasticizer, plasticizer-1; molecular weight 8000)
5 parts, heavy calcium carbonate (Super SSS; trade name manufactured by Maruo Calcium Co., Ltd.)
50 parts With respect to 166 parts by mass of this A kneaded rubber composition, the components shown below were mixed with an open roll to obtain an unvulcanized rubber composition.
・ Crosslinking agent (sulfur) 0.5 part ・ Vulcanization accelerator (dibenzothiazyl disulfide, MBTS; Noxeller DM; trade name, manufactured by Ouchi Shinko Chemical Co., Ltd.) 1 part ・ Vulcanization accelerator (tetramethylthiuram monosulfide, TMTM; Noxeller TS; trade name, manufactured by Ouchi Shinko Chemical Co., Ltd.) 1 part About the obtained unvulcanized rubber composition, the volume resistance of a rubber material which is molded into a sheet shape in the same manner as in Example 1 and becomes an elastic layer The rate was measured. As a result, the volume resistivity was 1.2 × 10 ⁸ Ω · cm.

  Next, using the unvulcanized rubber composition, a rubber roller 5 having an elastic layer on the outer periphery of the conductive metal core was molded in the same manner as in Example 1. Then, the circumferential unevenness of the electric resistance was measured. As a result, the circumferential unevenness of electric resistance was 1.2 times.

  A surface layer was coated on the elastic layer of the rubber roller 5 in the same manner as in Example 1 to obtain the charging roller 5. When this charging roller 5 was subjected to image evaluation in the same manner as in Example 1, a ghost image was generated.

(Comparative Example 2: Charging roller 6)
An unvulcanized rubber composition was obtained in the same manner as in Comparative Example 1 except that 4 parts of an ionic conductive agent (tetrabutylammonium perchlorate) was added as a component of the A kneaded rubber composition. About the obtained unvulcanized rubber composition, it shape | molded in the sheet form similarly to Example 1, and measured the volume resistivity of the rubber material used as an elastic body layer. As a result, the volume resistivity was 8.8 × 10 ⁶ Ω · cm.

  Next, a rubber roller 6 having an elastic layer on the outer periphery of the conductive metal core was molded by the same method as in Example 1 using the unvulcanized rubber composition. Then, the circumferential unevenness of the electric resistance was measured. As a result, the circumferential unevenness of electric resistance was 1.1 times.

  A surface layer was coated on the elastic layer of the rubber roller 6 in the same manner as in Example 1 to obtain the charging roller 6. When this charging roller 6 was subjected to image evaluation in the same manner as in Example 1, no ghost was observed and the halftone uniformity was good. Further, as a result of image evaluation after being left in a harsh environment in the same manner as in Example 1, an image defect that appears to be a transfer of contaminants from the charging roller 6 to the photosensitive member was observed.

(Comparative Example 3: Charging roller 7)
The components shown below were mixed with a pressure kneader to obtain an A-kneaded rubber composition.
・ Raw rubber (ethylene-propylene-diene terpolymer, EPDM; EPT4045; trade name, manufactured by Mitsui Petrochemical Co., Ltd.) 100 parts ・ Processing aid (zinc stearate) 1 part ・ Vulcanization acceleration aid (zinc oxide) 5 parts / filler (MT carbon black, MT-CB; Thermax Flow Foam N990; trade name, manufactured by Cancarb) 40 parts / plasticizer (paraffin oil, plasticizer-2; PW-380; trade name, manufactured by Idemitsu Kosan Co., Ltd.) )
50 parts heavy calcium carbonate (Super SSS; trade name manufactured by Maruo Calcium Co., Ltd.)
30 parts-Conductive agent (Ketjen Black, Ketjen Black EC600JD; Ketjen Black International Co., Ltd., trade name) 6 parts The following components are mixed in an open roll to 232 parts by mass of this A kneaded rubber composition. An unvulcanized rubber composition was obtained.
・ Crosslinking agent (sulfur) 0.5 part ・ Vulcanization accelerator (dibenzothiazyl disulfide, MBTS; Noxeller DM; trade name, manufactured by Ouchi Shinko Chemical Co., Ltd.) 1 part ・ Vulcanization accelerator (tetramethylthiuram monosulfide, TMTM; Noxeller TS; Ouchi Shinko Chemical Co., Ltd. product name) 1 part ・ Vulcanization accelerator (dipentamethylene thiuram tetrasulfide, DPTT; Noxeller TRA; Ouchi Shinko Chemical Co., Ltd.) 1 part The vulcanized rubber composition was molded into a sheet shape in the same manner as in Example 1, and the volume resistivity of the rubber material to be an elastic layer was measured. As a result, the volume resistivity was 1.0 × 10 ⁷ Ω · cm.

  Next, using the unvulcanized rubber composition, a rubber roller 7 having an elastic layer on the outer periphery of the conductive metal core was molded in the same manner as in Example 1. Then, the circumferential unevenness of the electric resistance was measured. As a result, the circumferential unevenness of electric resistance was 1.8 times.

  A surface layer was coated on the elastic layer of the rubber roller 7 in the same manner as in Example 1 to obtain the charging roller 7. When this charging roller 7 was subjected to image evaluation in the same manner as in Example 1, density unevenness due to electrical resistance unevenness of the charging roller occurred in the halftone image.

  The evaluation results described above are summarized in Table 1.

  Comparative Example 1 is an example in which a conductive member that does not contain the conductive filler of the present invention is used for a charging roller. The elastic layer has a high volume resistivity and a ghost image is generated. Comparative Example 2 is an example in which the conductive filler of the present invention is not included and a large amount of an ionic conductive agent is blended to reduce the volume resistance of the elastic layer, and no ghost image is generated, but photoconductor contamination is confirmed. It was. Comparative Example 3 is an example in which the conductive filler of the present invention is not included, and conductive carbon is blended to reduce the volume resistance of the elastic layer. The roller resistance has a large circumferential unevenness and the image uniformity is poor. .

  As is apparent from Table 1, when the conductive member containing the conductive filler of the present invention is used for a charging roller, the volume resistivity of the elastic layer is sufficiently low, so that the ghost image rank is good. The halftone uniformity is also good, and no photoconductor contamination has occurred.

It is a typical sectional view showing the composition of the charging roller as an example of the conductive member of the present invention. It is a schematic block diagram of the electrophotographic apparatus which has the electroconductive member of this invention. It is typical sectional drawing of the electroconductive filler used by this invention. It is a schematic diagram for demonstrating the measuring method of the circumferential nonuniformity of electrical resistance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Charging roller 11 Core metal 12 Elastic body layer 13 Surface layer 21 Image carrier (electrophotographic photosensitive member)
21a Photosensitive layer 21b Conductive support 21c Support shaft 23 Power supply 23a Sliding power supply 24 Exposure means 25 Development means 26 Transfer roller (transfer means)
27 Transfer material 28 Pre-exposure means 29 Cleaning means 31 Inorganic filler 32 Surfactant layer 33 Organic conductive agent layer 41 Aluminum drum 42 External power supply 43 Reference resistance 4a Rubber roller

Claims (3)

In a conductive member having a highly conductive base material and a semiconductive layer composed of at least one layer provided on the outside thereof, the semiconductive layer is
An inorganic filler, a surfactant layer having a surface coated with a surfactant, a repeating unit represented by the following general formula (I) and the following general formula (II) on the surfactant layer An organic conductive agent layer coated with an organic conductive agent having the repeating unit shown, and a conductive filler,
A conductive member containing

(Wherein n represents an integer of 10 or more, R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group or an alkyl-substituted phenyl group)

(In the formula, R3 represents a hydrogen atom or a methyl group, Q represents a divalent linking group, A represents a sulfonic acid group, a phosphoric acid group, a carboxylic acid group, or a group in which these acid groups have been neutralized. )   The conductive member according to claim 1, wherein the inorganic filler is calcium carbonate. The conductive member according to claim 1, wherein the organic conductive agent layer further contains a lithium salt.

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