JP2003140421A - Conductive member and electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive member which can eliminate the problems of initial fogging, durable fogging and OPC adhesiveness and ensures the good development operation, transfer operation, cleaning operation, etc., even under severe conditions and makes it possible to obtain good images. SOLUTION: The conductive member is a conductive member used for an electrophotographic device and is furnished with an elastic layer and at least one resin layer formed on this elastic layer, in which the outermost layer forming the member surface is formed of a resin material containing >=50 wt.% urethane denatured acrylic resin and <=50 wt.% fluororesin component and/or fluorine compound. The above conductive member is <=50 V in the maximum value of the surface potential after 0.3 seconds when the surface of the outermost resin layer is charged by applying a voltage of 8 kV to a corona discharger arranged apart a spacing of 1 mm from the surface of the outermost resin layer in a state not to contain conducting agents at all and is <=5 V in the surface potential after 10 seconds.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive member used in a developing device, a transfer device, a cleaning device or the like used in an electrophotographic device or an electrostatic recording process, and a developing device, a transfer device or a developing device using the conductive member. The present invention relates to an electrophotographic apparatus equipped with a cleaning device.

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic apparatus such as a copying machine or a printer, first, the surface of a photoconductor is uniformly charged, and an image is projected from the optical system on the photoconductor so that a portion exposed to light is exposed. An electrostatic latent image is formed by removing the electrostatic charge to form an electrostatic latent image, and then a toner image is formed by adhesion of toner, and the toner image is transferred to a recording medium such as paper, and then printed. The method is taken.

In these processes, first, regarding development, a non-magnetic one-component developer is supplied to a photosensitive drum or the like holding a latent image, and the developer is attached to the latent image on the photosensitive drum to form a latent image. A pressure developing method is known as a developing method for visualization (U.S. Pat. Nos. 3,152,2012 and 37311).
No. 46, etc.), this method does not require a magnetic material, so that the apparatus can be simplified and downsized, and the toner can be colored easily.

In this pressure developing method, as shown in FIG. 2, a developing roller 6 carrying a toner (non-magnetic one-component developer) holds a latent image on a photosensitive drum such as an electrostatic latent image. The development is performed by bringing the toner into contact with the body 5 and adhering the toner to the latent image of the latent image holding body 5. Therefore, the developing roller 6 is in close contact with the latent image holding body 5 such as a photosensitive drum. Must be securely held and rotated, and must be formed of an elastic body having conductivity.

Further, in a transfer device for transferring a toner image developed and visualized with toner from a latent image carrier onto a transfer sheet, conventionally, the transfer sheet is charged by using a corona charger to transfer the toner image onto the transfer sheet. Transfer is generally used, but corona discharge has problems such as generation of ozone and the need for a high-voltage power supply. As a transfer device that solves this problem, there is known a transfer device that charges a transfer paper 8 by using a bias roller (transfer roller) 9 made of conductive rubber, as shown in FIG. In this method, in order to obtain high transfer efficiency and a transferred image without unevenness, a constant nip width is set between the photosensitive drum 5 and the roller,
The pressure between the drums should be low and fairly soft conductive rubber must be used. In the apparatus of FIG. 2, the toner image transferred onto the transfer paper 8 is fixed by the fixing device 13.
Is heated and fixed on the transfer paper 8.

Further, the toner left on the photosensitive drum after the transfer of the toner image is removed by a cleaning device. As the cleaning device, the edge of a blade formed of urethane rubber or the like on a conventional photosensitive member is pressed. Generally, the toner is scraped off. However, when such a blade is used, the frictional force with the photoconductor is large, the driving force is large, the photosensitive drum is easily scratched by the edge, and when the rubber plate is scratched, cleaning cannot be performed in some cases. As one of the solutions to such a problem, as shown in FIG. 2, a cleaning roller 11 capable of applying a voltage is used.
There is proposed a cleanerless method in which a cleaning device 12 is configured by using a cleaning roller 11, and the cleaning roller 11 directly removes residual toner from the surface of the photosensitive drum 5 or forcibly charges the toner and collects the toner by a developing roller or the like. ing. This cleaning roller is also required to have the same characteristics as the above-mentioned transfer roller and the like.

Conventionally, as conductive members such as the developing roller, the transfer roller, and the cleaning roller, for example, on the surface of an elastic layer such as rubber or urethane foam, to secure the smoothness of the surface, adjust the resistance, and improve the charging property, Acrylic, urethane, nylon, polyethylene, epoxy, polyester, polyether, polystyrene, phenol, AB
It is known that a resin solution is formed by applying a resin solution of S, polyamide, urethane-modified acrylic resin or the like by a dipping method or a spray method.

[0008]

However, the above-mentioned conventional conductive member has the following problems. [Initial fog / durable fog] In response to the recent demands for higher image quality, lower cost (lower voltage, smaller members, etc.), higher speed, and higher durability in the electrophotographic field, a developing roller,
A conductive member such as a transfer roller or a cleaning roller may cause problems such as: initial image defect (initial fog), and durable image defect (durability fog) caused by stacking prints. However, the root cause of this has not been clarified, and there are currently no clear measures that can be fully satisfied.

[OPC contact] The conductive members such as the developing roller, the transfer roller, and the cleaning roller are the photosensitive member (OP).
Since it is in contact with C) for a long period of time, adhesion (adhesion) may occur between the photoconductor and the surface of these members, resulting in peeling of the coating film and contamination of the photoconductor. In particular, in recent years, there has been a strong demand for the development of a conductive member, particularly a resin layer on the surface of the member, which is excellent in releasability without coming into close contact with the photoconductor even under severe conditions such as temperature / humidity, etc., in response to demands for multi-environment.

The present invention has been made in view of the above circumstances, and is capable of solving the problems of [initial fog / durability fog] and [OPC adhesion], and good development operation and transfer even under severe conditions. An object of the present invention is to provide a conductive member capable of reliably performing an operation, a cleaning operation, etc. and stably obtaining a good image, and an electrophotographic apparatus using the conductive member.

[0011]

MEANS FOR SOLVING THE PROBLEMS AND BEST MODE FOR CARRYING OUT THE INVENTION As a result of intensive studies to achieve the above object, the present inventor has formed at least one resin layer on an elastic layer, When obtaining a conductive member such as a transfer roller or a cleaning roller, the outermost resin layer forming the surface of the member is set to 5
0 wt% or more urethane modified acrylic resin and 50 wt%
It is formed of a resin material containing the following fluororesin component and / or fluorine compound component, and is arranged at a distance of 1 mm from the surface of the outermost resin layer in a state where the outermost resin layer does not contain any conductive agent. When the outermost resin layer surface was charged by applying a voltage of 8 kV to the corona discharger and the corona discharge was generated, the maximum value of the surface potential after 0.3 seconds was 50 V or less and after 10 seconds. Surface potential is 5
By setting it to be V or less, it is possible to solve the above-mentioned problems of [initial fog / durability fog] and [OPC adhesion], and good development operation even under severe conditions, It has been found that a conductive member such as a developing roller, a transfer roller and a cleaning roller can be obtained which can perform a transfer operation or a cleaning operation and can stably obtain a good image.

[Initial fog / durable fog] According to the study by the present inventor, the above-mentioned [initial fog / durable fog] is
Mainly depends on the resin layer of the conductive member, particularly the outermost resin layer. Among them, as for “initial fogging”, in the state where the outermost resin layer of the conductive member does not contain any conductive agent, the surface of the outermost resin layer is When a voltage of 8 kV was applied to a corona discharger arranged at an interval of 1 mm to generate a corona discharge and the outermost resin layer surface was charged, the maximum value of the surface potential after 0.3 seconds was 50 V. When the conductive member is capable of retaining the “surface charging potential characteristic”, which is the following, and the surface potential after 10 seconds is 5 V or less, it is possible to extremely effectively prevent the occurrence of the “initial fog”. As for the "endurance fog", it was found that if the "initial fog" does not occur, it is much more advantageous than the "initial fog" even if there is some deterioration. On the other hand, in order to suppress "durability fog", in addition to the above "surface charging potential characteristic", it was found that the toner adhesion and frictional property of the outermost resin layer of the conductive member are important. That is, if the conductive member such as the developing roller, the transfer roller, or the cleaning roller has a property that the toner adheres much or the toner is hard to be removed, fogging occurs due to toner damage to the conductive member such as toner filming and toner fusion. Will be done. If the outermost resin layer has a high frictional property, the shear stress between the photoconductor and the conductive member becomes excessive, and fogging occurs due to damage such as slack, wrinkles, and holes. Therefore, as a result of further study on this point, when the conductive member is made of 100% cellulose, 30 g / m ² , and 70 mesh cloth and a pressure of 100 gf is applied to the cloth, the friction coefficient to the cloth is 0.5 or less. It has been found that the occurrence of this "durable fog" can be suppressed very effectively when it has friction characteristics.

Here, the reason for evaluating the surface potential characteristics when corona discharge is used as a measure against "fogging" is as follows. That is, "fogging" is a so-called image defect, which is caused by mechanical defects, environmental defects, electrical defects, and defects somewhere such as the developing roller, the transfer roller, and the cleaning roller. The most frequent cause of this is common to all rollers, and electrical failure due to surface residual charge is the most common cause. That is, all of these rollers play their role by applying a voltage, but when no voltage is applied, the presence of residual charge on the surface of the rollers causes electrical non-uniformity when a voltage is applied during operation. Will occur. This electrical non-uniformity appears as a fatal image defect for these conductive rollers, and causes fog such as so-called "white spots", "black spots", "horizontal stripes", and "vertical stripes". Therefore, when this voltage is not applied, the surface residual charge must be eliminated as much as possible. Therefore, the performance of preventing the occurrence of the above "fog" can be evaluated by the surface charge attenuation characteristic accompanying the surface potential measurement by corona discharge. In the present invention, the surface charge attenuation characteristic is evaluated and adjusted. .

Further, when the charging potential characteristic is evaluated, the evaluation is carried out in the state where the outermost resin layer contains no conductive agent at all. That is, in a conductive roller such as a developing roller, a transfer roller, or a cleaning roller, it is usual that the resistance increases from the shaft toward the outer layer. There is a reason. Therefore, it can be said that the surface charge permeability of the roller depends substantially only on the surface layer. And, in this surface layer, it may contain a conductive agent, in which case the conductive agent may help the surface charge decay to some extent, but when the conductive agent is a filler, the fillers are microscopically different from each other. Since there is almost no contact, the filler cannot completely prevent the charge from staying in the surface layer resin, and in the end, if the charge permeability of the resin alone is not excellent, there is no residual charge. It cannot be. Further, when the conductive agent is an ionic conductive agent, a concentration gradient of the ionic conductive agent is usually generated in the resin, and a portion in which the ionic conductive agent is hardly present is generated. The charge permeability of a single substance becomes important. Therefore, the charge permeability of the resin alone in the outermost resin layer is the most important parameter, and in the evaluation of surface potential characteristics, it is appropriate to perform the evaluation in the state where the outermost resin layer does not contain any conductive agent. It becomes.

Further, the reason for evaluating the charging potential 10 seconds after the charging by corona discharge is as follows. That is, a large potential of 8 kV (which is considered to be a slightly lower voltage in a conductive roller) is applied to the surface of the conductive roller by corona discharge, but such a large voltage is not normally applied in an actual machine. But,
Due to problems such as measurement accuracy, reproducibility, and measurement method, such a large voltage is applied. Therefore, considering this point,
This is because the surface potential is evaluated when an interval of 10 seconds is given to allow the charges to escape, and this evaluation method is appropriate based on empirical rules.

[OPC adhesion] The problem of [OPC adhesion] can be solved by the good releasability as described above. That is, when the contact angle of water on the outermost resin layer surface is 90 degrees or more, the problem of [OPC adhesion] is effectively solved,
It has been found that it is possible to effectively prevent the occurrence of inconveniences such as coating film peeling and photoreceptor contamination.

A resin material containing 50% by weight or more of a urethane-modified acrylic resin component and 50% by weight or less of a fluorine resin component and / or a fluorine compound component is used for a conductive member such as a developing roller, a transfer roller or a cleaning roller. By forming the outermost resin layer, the above-mentioned "surface electrification potential characteristics" that can solve the problem of "initial fog / durability fog"
It is possible to obtain the outermost resin layer having the above-mentioned characteristics, and moreover, the above-mentioned "friction characteristics" that can more reliably eliminate the problem of "durability fog" and the above-mentioned "surface contact angle" that can solve the problem of [OPC adhesion]. The outermost resin layer of the conductive layer can be easily formed, and good developing operation, transfer operation, and cleaning operation can be reliably performed even under severe conditions, and a good image can be stably obtained. The inventors have found that a member can be obtained, and completed the present invention.

Therefore, according to the present invention, a conductive member used in an electrophotographic apparatus comprises an elastic layer and at least one resin layer formed on the elastic layer, and constitutes the surface of the member. The outermost resin layer is a conductive member formed of a resin material containing 50% by weight or more of a urethane-modified acrylic resin and 50% by weight or less of a fluororesin component and / or a fluorine compound component, and the outermost resin 8 k in a corona discharger arranged at a distance of 1 mm from the surface of the outermost resin layer when the layer does not contain any conductive agent.
When a voltage of V is applied to generate corona discharge to charge the outermost resin layer surface, the maximum value of the surface potential after 0.3 seconds is 50 V or less, and the surface potential after 10 seconds. Is 5 V or less, and the electroconductive member is used as a developing member such as a developing roller, a transfer member such as a transfer roller, or a cleaning member such as a cleaning roller. Provide a device.

The present invention will be described in more detail below.
As described above, the conductive member of the present invention is one in which the outermost resin layer forming the surface of the member is formed of a resin material containing a urethane-modified acrylic resin and a fluororesin component and / or a fluorine compound component. .

The urethane-modified acrylic resin used for the resin material forming the outermost resin layer is an acrylic resin modified with a urethane component, and is obtained by chemically bonding the urethane resin and the acrylic resin component. be able to. Specifically, for example, with 2-hydroxypropyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, etc., a reaction between a polymer having a hydroxyl group introduced into an acrylic polymer and a urethane prepolymer having an isocyanate group at a molecular end, Alternatively, it is synthesized by the reaction of an acrylic component having a hydroxyl group at the molecular end (one end or both ends) with a urethane prepolymer having an isocyanate group at the end (A: methacrylic acid,
Methacrylic acid ester monomer or oligomer). In this case, as the urethane prepolymer, polyether type, polyester type, polyolefin type or the like is used. In the polymer thus obtained, the urethane chain and the acrylic chain may be bonded to each other in a block type or a graft type.

[0021]

[Chemical 1]

Further, the urethane-modified acrylic resin used in the present invention is not limited to the one obtained by the above-mentioned method, but other than that, a method of adding diisocyanate to the acrylic diol mixed system, both ends of the acrylic monomer are added. Alternatively, it can also be obtained by a method such as adding isocyanate polyester at one end, polyether, etc., and polymerizing or copolymerizing the urethane acrylate. Further, as the acrylic resin component used in these syntheses, those having a glass transition temperature Tg as a polymer from room temperature to about 80 ° C. are preferable, and in addition to the above 2-hydroxyethyl methacrylate and the like, for example, methyl (meth) It is also possible to use (meth) acrylic acid esters such as acrylate, ethyl (meth) acrylate, isobutyl (meth) acrylate, n-butyl (meth) acrylate, glycidyl (meth) acrylate, acrylonitrile and acrylamide. Further, a polymerizable monomer such as styrene, vinyl acetate, vinyl chloride, maleic acid and its derivative may be copolymerized with these.

Here, although not particularly limited,
The content of the acrylic resin component in the urethane-modified acrylic resin is 5 to 80% by weight, particularly 50 to 70% by weight.
Is preferred.

The urethane-modified acrylic resin is
Since the urethane component and the acrylic component are chemically bonded, various physical properties such as hardness, adhesiveness and frictional property can be adjusted by changing the composition ratio of them, which is why urethane-modified acrylic resin This is the reason why it is preferable as compared with the resin or elastomer material.

Here, the urethane-modified acrylic resin is not particularly limited, but it is preferable to use an active hydrogen group at the terminal or side chain, and to crosslink with a polyisocyanate compound or the like before use. In this case, as the polyisocyanate compound, tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MD
I), naphthalene diisocyanate (NDI), tolidine diisocyanate (TODI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), phenylene diisocyanate, xylylene diisocyanate (XDI), tetramethyl xylylene diisocyanate (TMXDI), cyclohexane diisocyanate, Lysine ester triisocyanate,
Examples thereof include undecane triisocyanate, hexamethylene triisocyanate, triphenylmethane triisocyanate, and polymers, derivatives, modified products and hydrogenated products of these isocyanate compounds. Among these, particularly aliphatic or alicyclic isocyanates such as hexamethylene diisocyanate and isophorone diisocyanate, and polymers, derivatives and modified products thereof are preferably used because they are excellent in ozone resistance and heat resistance.

From the viewpoint of improving the adhesiveness with the mating material, a silicone component may be contained in the urethane-modified acrylic resin. Specifically, for example, a method of synthesizing by reacting a urethane prepolymer using a polyol containing a silicone chain as a raw material and an acrylic component can be considered. In this case, the content of the silicone component in the urethane prepolymer is 2 to 80% by weight, especially 5
It is preferably ˜50% by weight. The composition of the silicone component in the urethane-modified acrylic resin after the reaction is preferably 1 to 60% by weight, more preferably 3 to 30% by weight.

These urethane-modified acrylic resins have good electrical and mechanical properties and physical properties that are preferable as a skin layer of a conductive member, but they also have the disadvantage of high tackiness and large friction. Therefore, in the present invention, the above-mentioned problems of tackiness and frictional properties are solved while maintaining the above electrical characteristics and mechanical characteristics by adding and using a fluororesin component and / or a fluorine compound component.

Examples of the fluororesin component include polytetrafluoroethylene, polytetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene- Ethylene copolymer, polychlorotrifluoroethylene, chlorotrifluoroethylene-ethylene copolymer, tetrafluoroethylene-vinylidene fluoride copolymer, polyvinylidene fluoride, polyvinylidene fluoride copolymer, vinylidene fluoride-hexa Examples include fluoropropylene copolymers, and one or more of these can be used.

The fluororesin component and the urethane-modified acrylic resin may be simply blended, or may be chemically bound by a graft, a bond via a crosslinking agent such as isocyanate, or the like.

Further, as the fluorine compound component, perfluorooctylethyl methacrylate, 2,2,3,4,
4,4-hexafluorobutyl methacrylate, 2,2,3,
Examples thereof include 3-tetrafluoropropyl methacrylate, trifluoroethyl methacrylate, a fluorine-modified acrylate having a fluoroalkyl group bonded to the end of a polyol, and a fluorine-modified polyamide having a fluoroalkyl group bonded to the end of a polyamide. One or two of these may be mentioned. More than one species can be used.

Here, although not particularly limited,
The fluoroalkyl group C _n F _{2n + 1} in the fluorine compound preferably has n of 6 or more. This is because when n is 5 or less, the low surface energy peculiar to the fluoroalkyl group may not be sufficiently exhibited, and when n is 6 or more, the characteristics are rapidly exhibited, and low friction property and low adhesiveness are good. This is because it is often exhibited in.

The fluorine compound component and the urethane-modified acrylic resin may be simply blended, but it is particularly preferable that they are chemically bound by a bond such as a graft or a crosslinking agent such as isocyanate. . This is because when the fluorine compound has a low molecular weight, there is a possibility that contamination of the photoreceptor and a decrease in durability may occur due to bleed-out. In addition, the outermost resin layer preferably has an inclined structure in which fluorine is dense on the outside and urethane-modified acrylic is dense on the inside from the viewpoint of action and effect, but the fluorine compound is low in polarity, Even if it is bonded to the urethane-modified acrylic resin, it is more likely to be on the air side, that is, the outermost side. Therefore, even if bonded to the urethane-modified acrylic resin, there is no particular disadvantage in obtaining the inclined structure.

In the present invention, the fluororesin component and the fluorocompound component may be used in combination.

The outermost resin layer constituting the member surface of the conductive member of the present invention contains the urethane-modified acrylic resin as the resin component and the fluorine resin component and / or the fluorine compound component as described above. In this case, the urethane modified acrylic resin is 50% by weight or more, more specifically 50 to 99.9% by weight, preferably 60 to 99% by weight, and the fluorine resin component and / or the fluorine compound component is 50% by weight or less. , More specifically 0.1 to 50% by weight,
It is preferably 1 to 40% by weight. here,
When the urethane-modified acrylic component is less than 50% by weight,
Good electrical and mechanical properties peculiar to the urethane-modified acrylic resin may not be obtained, and if the amount of the fluororesin component and / or the fluorine compound component is too small, the effect on tack is not observed so much, while if too large, The potency does not change so much, which may cause inconvenience such as phase separation and deterioration of electric characteristics.

Although not particularly limited, silica powder can be added and compounded in the resin material forming the outermost resin layer, which reduces the contact area and reduces the adhesion (non-adhesiveness). ) May be improved. Further, in this resin material, a conductive agent can be added as necessary to adjust the resistance to a desired value. In this case, the conductive agent is not particularly limited, and various electronic conductive agents and various ionic conductive agents can be used. Although an agent can be used, a conductive powder such as carbon is particularly preferably used in the present invention. The electric resistance of the outermost resin layer is not particularly limited, but is usually 10 ⁶ to 10 ¹³ Ω · cm, particularly 10 ⁷ to 10
It is preferably ¹² Ω · cm.

The method for forming the outermost resin layer on the conductive member is not particularly limited, but a paint containing the above-mentioned components is prepared and the paint is applied to the conductive member by a dipping method or a spray method. The method is preferably used.

The thickness of the outermost resin layer is appropriately set according to the form of the conductive member and is not particularly limited, but is usually 50 μm or less, particularly preferably 2 to 30 μm. If it exceeds 50 μm, the outermost resin layer may be hardened and the flexibility of the outermost resin layer may be impaired.

If necessary, additives such as a crosslinking agent, a thickener, a thixotropy-imparting agent and a structural viscosity-imparting agent can be added to the resin composition forming the outermost resin layer.

The conductive member of the present invention may be one in which at least the surface of the member is formed of the outermost resin layer, and its form is roll-like or plate-like depending on the use and the configuration of the electrophotographic apparatus used. It may be in any suitable form such as a block, a sphere, or a brush, and is not particularly limited, but it is usually preferable to use a roll-shaped conductive roller having the outermost resin layer on the member surface. , For example,
As shown in FIG. 1A, a conductive roller in which an elastic layer 2 is formed on the outer circumference of a shaft 1 and the outermost resin layer 3 is formed on the elastic layer 2 can be exemplified.

In this case, a metal or plastic shaft can be used as the shaft 1.
The shaft 1 may be omitted depending on the form of the member and the mechanism of the electrophotographic apparatus in which the conductive member is used.

The elastic body forming the elastic layer 2 is not particularly limited as long as it is an elastic body capable of obtaining a good contact state with a mating member such as a photosensitive drum or transfer paper.
Known rubber or resin, or foams thereof (hereinafter,
"Form"). Specifically, polyurethane, silicone rubber, butadiene rubber, isoprene rubber, chloroprene rubber, styrene-butadiene rubber, ethylene-propylene rubber, polynorbornene rubber, styrene-butadiene-styrene rubber, epichlorohydrin rubber, acrylic rubber, nitrile rubber, etc. A rubber composition as a base rubber is exemplified.

By adding a conductive agent to the elastic layer 2, conductivity can be imparted or adjusted to a predetermined resistance value. The conductive agent is not particularly limited,
Lauryl trimethyl ammonium, stearyl methyl ammonium, octadodecyl trimethyl ammonium,
Hexadecyltrimethylammonium, modified fatty acid / dimethylethylammonium perchlorate, chlorate, borofluoride, sulfate, ethosulfate salt, benzyl bromide, benzyl chloride, etc. Cationic surfactant such as quaternary ammonium salt, aliphatic sulfonate, higher alcohol sulfate ester salt, higher alcohol ethylene oxide addition sulfate ester salt, higher alcohol phosphate ester salt, higher alcohol ethylene oxide addition phosphate ester salt, etc. anionic surfactants, higher alcohol ethylene oxide, polyethylene glycol fatty acid esters, polyhydric alcohol fatty acid antistatic agent such as a nonionic antistatic agents such as _{esters, NaClO 4, LiAsF 6, LiBF} 4, NaSC
Electrolytes such as metal salts of Group 1 of the periodic table such as Li ⁺ , Na ⁺ and K ⁺ such as N, KSCN and NaCl, or salts of NH ₄ ⁺ , and conductive carbon such as Ketjen black and acetylene black , SAF, ISAF, HAF, FE
Carbon for rubber such as F, GPF, SRF, FT, MT,
Oxidized carbon for color (ink), pyrolytic carbon, natural graphite, artificial graphite, antimony-doped tin oxide, titanium oxide, zinc oxide, nickel, copper, silver, and metal oxides such as germanium, polyaniline Conductive polymers such as polypyrrole and polyacetylene. In this case, the blending amount of these conductive agents is appropriately selected according to the type of composition and the type of conductive member and is not particularly limited, but usually the volume resistivity of the elastic layer is 10 ⁴ to 10 ^4. It is adjusted to ⁹ Ω · cm, preferably 10 ⁵ to 10 ⁷ Ω · cm.

The thickness of the elastic layer 2 is appropriately set according to the type, form, size, layer structure, etc. of the member and is not particularly limited, but will be described with reference to FIG. In the case of a roll-shaped conductive member as shown in FIG. 1 (B), it is usually preferably 2 to 30 mm, particularly preferably 3 to 20 mm.

Here, the outermost resin layer 3 is coated on the elastic layer 2 with a coating material of a resin material made of a urethane-modified acrylic resin containing the fluororesin component and / or the fluorine compound component as described above. When formed, the solvent used for the paint may be water-based or solvent-based.

If necessary, an intermediate resin layer 4 can be provided between the outermost resin layer 3 and the elastic layer 2 as shown in FIG. 1 (B). In this case, the resin forming the intermediate resin layer 4 is not particularly limited, but an aqueous resin is preferably used. As the water-based resin, any type may be used as long as the solvent is water, and there are water-soluble type, emulsion type, suspension type and the like, and a resin having active hydrogen such as carboxyl group, hydroxyl group and amino group is preferably used. . More specific examples include polyester-based, acrylic-based, urethane-based, and hot water-soluble systems such as polydioxolane. Among these, acrylic resin has a much smaller dielectric constant than urethane, nylon, etc., which have been widely used as a resin for conductive members, so that the electrostatic capacity also becomes smaller, and the electrical conductivity between the conductive member and the photoconductor due to the application of alternating current is reduced. It is particularly preferably used because the attractive force and repulsive force are reduced and the generation of charging noise is suppressed. Among the acrylic resins, a soap-free emulsion type one having a glass transition temperature of −50 to 10 ° C., a content ratio of a carboxyl group and a hydroxyl group of 2 to 5% by weight, has a good crosslinking effect and a low hardness. It is preferably used because it is possible.

A conductive agent may be added to the intermediate resin layer 4 to impart or adjust conductivity. In this case, as the conductive agent, the same conductive agents as those exemplified for the elastic layer 2 can be exemplified, but it is preferable to use carbon among them, and particularly, the oxygen content is 5% or more,
In particular, 7% or more, more preferably 9% or more,
Further, the pH is preferably 5 or more, particularly 6 or more, and further preferably 7 or more. That is, the oxygen content of ordinary carbon is about 0.1 to 3%, and there is some carbon that has been subjected to an oxidation treatment, but the oxygen content of this oxidation-treated carbon slightly increases. As a result, the pH tends to shift to the acidic side, and if the carbon is acidic, the stability may decrease when added to the water-based resin. On the other hand, the above-mentioned carbon maintains neutrality or alkalinity despite having a large oxygen content, and can be stably added to the water-based resin. Further, those obtained by adding a functional group such as a carboxyl group, a hydroxyl group or a ketone group to the surface of carbon and substituting a part of hydrogen contained in these groups with an alkali metal such as sodium are preferably used. In addition, this specific oxygen content and pH
When the outermost resin layer 3 is formed of a water-based paint, the carbon having a value is also suitably used as the carbon to be added to the outermost resin layer 3 as a conductive agent.

The intermediate resin layer 4 contains appropriate additives such as a film-forming aid, a pigment dispersant, a thickener, a leveling agent, a thixotropy-imparting agent, and a structural viscosity-imparting agent within the range not departing from its purpose. Can be added in an appropriate amount if necessary.

The intermediate resin layer 4 is preferably formed by using a water-based resin as described above, but it may contain a resin other than this water-based resin, and if necessary, this intermediate resin layer 4 It is also possible to form a plurality of intermediate resin layers 4.

The method for forming the intermediate resin layer 4 is not particularly limited, and a known dipping method, spray method, extrusion molding method, or the like can be adopted. Usually, a coating in which each component is dissolved or dispersed in a solvent is used. Is preferably used to form a coating film by a dipping method.

As described above, the conductive member of the present invention has the outermost resin layer 3 formed on the elastic layer 2 via the intermediate resin layer 4 or directly. In this case, suitable resistance as a conductive member is obtained in any layer structure and application.
Volume resistance is 10 ⁵ to 10 ¹¹ Ωc to obtain a good image
m is preferable, and particularly 10 ⁶ to 10 ¹⁰ Ωcm
Is preferred.

Here, in the conductive member of the present invention, the above outermost resin layer contains no conductive agent (when the outermost resin layer is mixed with the conductive agent, the conductive agent is excluded). Except for the above-mentioned conductive member), a voltage of 8 kV is applied to a corona discharger arranged at a distance of 1 mm from the surface of the outermost resin layer to generate corona discharge, and When charged, the maximum value of the surface potential after 0.3 seconds is 50 V or less, especially 35 V or less, and the surface potential after 10 seconds is 5 V or less, especially 3.5 V.
The surface potential characteristic is that As a result, it is possible to reliably prevent the occurrence of the above-mentioned "fog", particularly the "initial fog". Further, according to the conductive member of the present invention in which the outermost resin layer is formed, such surface potential characteristics can be easily achieved.

As a specific method for measuring the surface potential of the conductive member and evaluating the surface potential characteristics, for example, "Charge Roller Test System CRT2000" manufactured by QEA (Quality Engineering Associates, Inc.) in the United States is used. , As shown in FIG. That is,
The conductive member (conductive roller in the figure) on which the outermost resin layer is formed is used as a subject roller 21, and both ends of a shaft 22 of the subject roller 21 are fixed to a chuck 23, and a small scorotron discharger 24 and a surface electrometer are provided. 25 and the measuring unit 20 provided side by side with a predetermined distance from each other.
It is arranged facing the surface of No. 1 with a space of 1 mm,
The measurement unit 20 is moved from one end to the other end of the subject roller 21 at a constant speed while the subject roller 21 is kept stationary, and the surface potential of the subject roller 21 is measured while applying a surface charge to the subject roller 21. At this time, the moving speed of the measuring unit 20 may be adjusted to measure the “surface potential after 0.3 seconds” and the “surface potential after 10 seconds”. In this case, since the surface potential depends on temperature and humidity, the measurement is carried out in an atmosphere of normal temperature and normal humidity (22 ° C./50% RH) as standard conditions. The corona charge applied from the scorotron discharger 24 to the subject roller 21 is a negative charge, and the applied voltage is 8 kV as described above.

The conductive member of the present invention preferably has a small frictional resistance on the surface thereof, and although not particularly limited, a load of 100 gf is applied to a cloth of 100% cellulose, 30 g / m ² , 70 mesh. It is preferable that the friction coefficient with respect to the cloth when pressed against the surface is 0.5 or less, particularly 0.35 or less. This causes "fog",
In particular, it is possible to more reliably prevent the occurrence of "durable fog". Further, according to the conductive member of the present invention in which the outermost resin layer is formed, such surface friction characteristics can be easily achieved.

In this case, the friction coefficient can be measured by the measuring device shown in FIG. That is, the cellulose 10 is attached to the movable stage 52 provided on the base 51.
A 0%, 30 g / m ² , 70 mesh cloth (Bencott lint-free) 15 is fixed, and the conductive member 14 of the present invention to be evaluated is placed on the cloth 15 in a state of being contacted, and 100 gf is applied by the pressing means 53. Is applied to bring the cloth 15 and the conductive member 14 into pressure contact with each other, and in this state, the movable stage 52 is moved back and forth to move the friction speed 10
The cloth 15 and the conductive member 14 are frictionally moved at 0 mm / min, and the friction resistance at this time is measured by the load cell 54.
From the frictional resistance value above cloth (Bencott lint free)
The friction coefficient of the conductive member 14 with respect to 15 may be obtained.
In addition, as a friction partner material, cellulose 100%, 30 g
/ M ² , 70 mesh cloth (Bencott lint free)
The reason for selecting was that the surface properties of the conductive members such as the developing member, the transfer member, and the cleaning member were most correlated,
This is because the obtained measurement range of the friction coefficient was appropriate.

Further, the conductive member of the present invention is not particularly limited, but the contact angle with water on the member surface, that is, the surface of the outermost resin layer is 90 degrees or more, particularly 95 degrees or more. It is preferable that the problem of peeling of the coating film and the contamination of the mating member caused by the close contact with the mating member such as the photoconductor can be solved more reliably, and the conductive material of the present invention having the outermost resin layer is formed. According to the member, such a contact angle can be easily achieved.

[0056]

EFFECTS OF THE INVENTION The conductive member of the present invention can solve the problems of [initial fog / durable fog] and [OPC adhesion] described above, and can perform good developing operation, transfer operation, and cleaning even under severe conditions. The operation and the like can be reliably performed, and a good image can be stably obtained by using it as a developing member, a transfer member, a cleaning member, etc. of the electrophotographic apparatus.

[0057]

EXAMPLES The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[Example 1] (Developing member) A urethane-modified acrylic resin "EAU137B" (Asia Kogyo) was dissolved in a methyl ethyl ketone (MEK) solvent,
Furthermore, after adding 10 parts by weight of a fluororesin "MODIPER F200" (Nippon Oil & Fats Co., Ltd.) composed of a fluorine-acrylic block copolymer to 100 parts by weight of a urethane-modified acrylic resin, an isocyanate crosslinking agent was further added to NCO.
A paint A was prepared by adding the paint so that the index was 1.5. The contact angle between the sheet formed by drying the paint A and water and the water was 100 degrees.

An elastic layer (volume resistivity 10 ⁵ Ω) made of isoprene rubber having a resistance value adjusted by adding a conductive agent (carbon black) to the outer periphery of the metal shaft and having a thickness of 6 mm.
.Cm) to form an isoprene rubber roller.
By dipping this isoprene rubber roller in the coating material A and drying it, about 1 is applied onto the isoprene rubber elastic layer.
An outermost resin layer A having a thickness of 0 μm was formed to prepare a developing roller having the same layer structure as that shown in FIG.

The surface roughness of the obtained roller was 4.1 μm in terms of JIS ten-point average roughness Rz. In addition, when a voltage of 8 kV was applied to the corona discharger arranged with a distance of 1 mm from the roller surface to generate corona discharge and the surface was charged, the maximum surface potential after 0.3 seconds was reached. The value is 4 V, and the surface potential after 10 seconds is 0.35.
It was V. Further, using the measuring device shown in FIG. 3, this roller was subjected to a friction test using a cloth of 100% cellulose, 30 g / m ² , 70 mesh under the condition of temperature 22 ° C./humidity 50% RH. The coefficient was 0.16.

[Example 2] (Developing member) A urethane-modified acrylic resin "EAU137B" (Asia Kogyo Co., Ltd.) was dissolved in a MEK solvent, and a fluororesin "Kainer 7201" (Elf Atchem Co.) was added to 100 parts by weight of the urethane-modified acrylic resin. After adding 30 parts by weight, the isocyanate cross-linking agent has an NCO index of 1.
5 was added to prepare coating material B. This paint B
The contact angle between the sheet formed by drying and the water was 96 degrees.

An isoprene rubber roller similar to that used in Example 1 was dipped in the coating material B and dried to form an outermost resin layer B of about 10 μm on the isoprene rubber elastic layer of the roller.
To form a developing roller having the same layer structure as that shown in FIG.

The surface roughness of the obtained roller was 4.7 μm in JIS ten-point average roughness Rz. In addition, when a voltage of 8 kV was applied to the corona discharger arranged with a distance of 1 mm from the roller surface to generate corona discharge and the surface was charged, the maximum surface potential after 0.3 seconds was reached. The value is 19 V, and the surface potential after 10 seconds is 1.3.
It was 7V. Further, using the measuring device shown in FIG. 3, this roller was subjected to a friction test using a cloth of 100% cellulose, 30 g / m ² , 70 mesh under the condition of temperature 22 ° C./humidity 50% RH. The coefficient was 0.31.

[Example 3] (Developing member) A urethane-modified acrylic resin prepared by grafting an acrylic polymer obtained by polymerizing an acrylic monomer containing 80% by weight of a fluorine-containing acrylic monomer with respect to the total acrylic monomer to a urethane prepolymer. Was dissolved in a MEK solvent, and an isocyanate cross-linking agent was added thereto so that the NCO index was 1.5, whereby a coating C was prepared. The contact angle between the sheet formed by drying the coating material C and water and water was 96 °.

An isoprene rubber roller similar to that used in Example 1 was dipped in the above paint C and dried to form an outermost resin layer C of about 10 μm on the isoprene rubber elastic layer of the roller.
To form a developing roller having the same layer structure as that shown in FIG.

The surface roughness of the obtained roller was 3.7 μm in terms of JIS ten-point average roughness Rz. In addition, when a voltage of 8 kV was applied to the corona discharger arranged with a distance of 1 mm from the roller surface to generate corona discharge and the surface was charged, the maximum surface potential after 0.3 seconds was reached. The value is 5 V, and the surface potential after 10 seconds is 0.57.
It was V. Further, using the measuring device shown in FIG. 3, this roller was subjected to a friction test using a cloth of 100% cellulose, 30 g / m ² , 70 mesh under the condition of temperature 22 ° C./humidity 50% RH. The coefficient was 0.28.

[Comparative Example 1] (Developing member) Urethane-modified acrylic resin "EAU65B" (Asia Kogyo Co., Ltd.) was dissolved in a MEK solvent, and an isocyanate crosslinking agent was added with N.
A coating material D was prepared by adding it so that the CO index was 1.5. The contact angle between water and a sheet formed by drying this paint D was 84 degrees.

An isoprene rubber roller similar to that used in Example 1 was dipped in the above coating D and dried to form an outermost resin layer D of about 10 μm on the isoprene rubber elastic layer of the roller.
To form a developing roller having the same layer structure as that shown in FIG.

The surface roughness of the obtained roller was 3.3 μm in JIS ten-point average roughness Rz. In addition, when a voltage of 8 kV was applied to the corona discharger arranged with a distance of 1 mm from the roller surface to generate corona discharge and the surface was charged, the maximum surface potential after 0.3 seconds was reached. The value is 3 V, and the surface potential after 10 seconds is 0.17.
It was V. Further, using the measuring device shown in FIG. 3, this roller was subjected to a friction test using a cloth of 100% cellulose, 30 g / m ² , 70 mesh under the condition of temperature 22 ° C./humidity 50% RH. The coefficient was 1.52.

[Comparative Example 2] (Developing member) A fluororesin "LF710" (Asahi Glass Co., Ltd.) was dissolved in a MEK solvent, and an isocyanate cross-linking agent was added so that the NCO index became 1.5, to prepare a coating E. . The contact angle between the sheet formed by drying the coating material E and water was measured and found to be 98 degrees.

An isoprene rubber roller similar to that used in Example 1 was dipped in the coating material E and dried to form an outermost resin layer E of about 10 μm on the isoprene rubber elastic layer of the roller.
To form a developing roller having the same layer structure as that shown in FIG.

The surface roughness of the obtained roller was 3.8 μm in JIS ten-point average roughness Rz. In addition, when a voltage of 8 kV was applied to the corona discharger arranged with a distance of 1 mm from the roller surface to generate corona discharge and the surface was charged, the maximum surface potential after 0.3 seconds was reached. The value is 600 V, and the surface potential after 10 seconds is 42.
It was 0V. Further, using the measuring device shown in FIG. 3, this roller was subjected to a friction test using a cloth of 100% cellulose, 30 g / m ² , 70 mesh under the condition of temperature 22 ° C./humidity 50% RH. The coefficient was 0.31.

Regarding the developing rollers of Examples 1 to 3 and Comparative Examples 1 and 2, the OPC adhesion (adhesion) was performed by the following method.
Initial image fog, toner transportability, toner chargeability, image fog after endurance, and development roller abrasion were evaluated. The results are shown in Table 1.

[OPC adhesion (adhesion)] The roller to be tested was mounted as a developing roller on the printer cartridge shown in FIG. 2 and left for 1 week under the condition of 40 ° C./80% RH. The adhesion was examined. [Initial image fog] A roller to be tested is mounted as a developing roller on the printer cartridge shown in FIG. 2, a developing bias voltage is set to 400 V, a non-magnetic one-component toner having an average particle size of 7 μm is used, and a peripheral speed of 60 mm / sec. The image was reproduced by reversal development while rotating at a high speed, and the image quality (presence or absence of fog and degree) in each of the initial white background, halftone, and black background images was evaluated. [Toner Conveying Property] The roller to be tested is mounted as a developing roller on the printer cartridge shown in FIG.
The toner conveyance amount was investigated by rotating at a peripheral speed of / sec to form a uniform thin toner layer on the surface of the developing roller, sucking the thin toner layer, and measuring the weight. [Toner chargeability] A roller to be tested is mounted as a developing roller on the printer cartridge shown in FIG.
It was rotated at a peripheral speed of / sec to form a uniform thin toner layer on the surface of the developing roller. The thin toner layer was sucked and introduced into a Faraday gauge, and the amount of charge was measured. [Image Fogging After Durability] After the above-mentioned [initial image fogging] test, a durability test of 10,000 sheets was performed, and then the same image evaluation was performed. [Abrasion of Developing Roller] The tested roller after the durability test was taken out, and the surface of the roller was observed with a video microscope to evaluate the degree of scratches and abrasion.

[0075]

[Table 1] Evaluation criteria : Very good ○ △: Good △: Normal △ ×: Not very good ×: Poor

[Example 4] (Transfer member) Urethane-modified acrylic resin "EAU53B" (Asia Kogyo Co., Ltd.) was dissolved in a MEK solvent, and a fluororesin "MODIPER F200" (Nippon Yushi-Seiyaku Co., Ltd.) composed of a fluorine-acrylic block copolymer was further dissolved. After adding 15 parts by weight to 100 parts by weight of urethane-modified acrylic resin, 10 parts by weight of carbon powder and NC of isocyanate crosslinking agent are further added.
A paint F was prepared by adding O so that the O index was 1.5. The contact angle between the sheet formed by drying this coating material F and water was measured and found to be 98 degrees.

On the outer circumference of the metal shaft, a 6 mm-thick elastic layer (volume resistivity 10 ⁷ ) made of urethane foam whose resistance value was adjusted by adding a conductive agent (carbon black).
Ω · cm) to form a urethane foam roller. This urethane foam roller is dipped in the coating material F and dried to form an outermost resin layer F having a thickness of about 10 μm on the urethane foam elastic layer, as shown in FIG.
A transfer roller having a layer structure similar to that of was prepared.

A roller was prepared in the same manner except that the conductive agent carbon was not added to the outermost resin layer F.
When a voltage of 8 kV was applied to the corona discharger arranged at a distance of 1 mm from this roller surface to generate corona discharge and the surface was charged, the maximum value of the surface potential after 0.3 seconds was It was 3 V and the surface potential after 10 seconds was 0.29 V. Also, using the measuring device shown in FIG. 3, this roller was subjected to a friction test using a cloth of 100% cellulose, 30 g / m ² , 70 mesh under the condition of temperature 22 ° C./humidity 50% RH. The coefficient is 0.17
Met.

[Comparative Example 3] (Transfer member) Urethane-modified acrylic resin "EAU65B" (Asia Kogyo Co., Ltd.) was appropriately adjusted in concentration, and 8 parts by weight of carbon powder was added to 100 parts by weight of urethane-modified acrylic resin. The NCO index of the isocyanate cross-linking agent is 1.
A coating material G was prepared by adding the coating material so that the weight ratio became 5. The contact angle between the sheet formed by drying the paint G and water and the water was measured and found to be 87 degrees.

A urethane foam roller similar to that used in Example 4 was dipped in the coating material G and dried to form an outermost resin layer G having a thickness of about 10 μm on the urethane foam elastic layer of the roller. A transfer roller having the same layer structure as in (A) was prepared.

A transfer roller was prepared in the same manner except that the conductive agent carbon was not mixed in the outermost resin layer G, and a voltage of 8 kV was applied to a corona discharger arranged at a distance of 1 mm from the roller surface. When a voltage was applied to generate corona discharge to charge the surface, the maximum value of the surface potential after 0.3 seconds was 6 V, and the surface potential after 10 seconds was 0.
It was 31V. Also, using the measuring device shown in FIG.
A friction test was conducted on this roller under the conditions of temperature 22 ° C./humidity 50% RH using a cloth of 100% cellulose, 30 g / m ² , 70 mesh, and the friction coefficient was 0.88.

The transfer rollers of Example 4 and Comparative Example 3 were pressed against the photosensitive drum with a load of 1 kg, and the temperature was 50 ° C./humidity was 8
When left in an environment of 5% RH for 2 weeks, the roller of Example 4 did not have any particular problem, whereas Comparative Example 3
There was sticking and contamination between the roller and the photosensitive drum. Further, when both transfer rollers were set in a laser beam printer and 5,000 sheets of images were printed, no particular problem was observed with the roller of Example 4, but with the roller of Comparative Example 3, the toner on the roller surface was Due to stains, blank characters in the image and stains on the back surface of the transfer paper occurred.

[Embodiment 5] (Cleaning member) An elastic layer (1.0 × 10 ³ Ω · c) formed on the outer periphery of a metal shaft and made of conductive urethane foam having a thickness of 3 mm.
m), the following intermediate resin layer H having a thickness of 100 μm is formed, and further the outermost resin layer I having a thickness of 10 μm is formed on the intermediate resin layer H having the same layer structure as in FIG. 1B. Created a cleaning roller.

The intermediate resin layer H is formed by applying a coating material H in which carbon is added to an aqueous acrylic resin by a dipping method, and has a volume resistivity of 5 × 10 ^7.
Adjusted to Ω · cm. Outermost resin layer I Urethane-modified acrylic resin "EAU53B" (Asia Kogyo Co., Ltd.) was dissolved in MEK solvent, and fluororesin "LF2" was used.
00 "(Asahi Glass Co., Ltd.) is a urethane-modified acrylic resin 100
After adding 50 parts by weight to parts by weight, 30 parts by weight of carbon powder and an isocyanate cross-linking agent are added so that the NCO index becomes 1.5, to prepare a paint I. The paint I is prepared by a dipping method. It was formed by coating. Further, the contact angle between the sheet obtained by drying the above paint I and water was measured and found to be 93 degrees.

The surface roughness of the obtained roller was JIS ten-point average roughness Rz of 1.0 μm. Further, a roller was prepared in the same manner except that carbon as a conductive agent was not mixed with the outermost resin layer I, and a voltage of 8 kV was applied to a corona discharger arranged at a distance of 1 mm from the roller surface. Then, when corona discharge was generated to charge the surface, the maximum value of the surface potential after 0.3 seconds was 21V, and the surface potential after 10 seconds was 1.88V. Further, by using the measuring device shown in FIG.
Cellulose 100% at 2 ° C / humidity 50% RH 3
When a friction test was conducted using a cloth of 0 g / m ² , 70 mesh, the friction coefficient was 0.28.

When the above cleaning roller was mounted on a printer cartridge and left for 2 weeks in an environment of temperature 40 ° C./humidity 95% RH, sticking to the photosensitive drum was not observed. In addition, a good image was obtained when an image was printed using the cartridge, and a continuous image was obtained.
No image deterioration was observed even when 0 images were printed.

[Comparative Example 4] (Cleaning member) An intermediate resin layer H similar to that of Example 4 was formed on the surface of an elastic layer similar to that of Example 5, and the following outermost resin having a thickness of 10 μm was formed thereon. Layer J was formed to prepare a cleaning roller having the same layer structure as that shown in FIG.

Outermost resin layer J Urethane-modified acrylic resin "EAU151B" (Asia Kogyo Co., Ltd.) was dissolved in a MEK solvent, and a coating material J having an isocyanate cross-linking agent added so that the NCO index became 1.5 was applied by the dipping method. Formed. Also,
The contact angle between the sheet obtained by drying the above paint J and water was 85 °.

The surface roughness of the obtained roller was 0.5 μm in JIS ten-point average roughness Rz. In addition, when a voltage of 8 kV was applied to the corona discharger arranged at a distance of 1 mm from this roller surface to generate corona discharge and the surface was charged, the maximum surface potential after 0.3 seconds was reached. The value is 3 V, and the surface potential after 10 seconds is 0.23.
It was V. Further, using the measuring device shown in FIG. 3, this roller was subjected to a friction test using a cloth of 100% cellulose, 30 g / m ² , 70 mesh under the condition of temperature 22 ° C./humidity 50% RH. The coefficient was 1.21.

When the cleaning roller was attached to a printer cartridge and left for 2 weeks in an environment of temperature 40 ° C./humidity 95% RH, sticking to the photosensitive drum occurred. In addition, when an image was printed using the cartridge, one stripe pattern was contaminated in the lateral direction at the photosensitive drum cycle. Further, in the image display, white background fogging occurred due to poor cleaning.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view illustrating a conductive member according to the present invention.

FIG. 2 is a schematic view showing an example of an electrophotographic apparatus using the conductive member of the present invention.

FIG. 3 is a schematic view showing an example of a measuring device for measuring a friction coefficient on the surface of a conductive member.

FIG. 4 is a schematic view showing an example of an apparatus for measuring a surface charging potential characteristic of a conductive member.

[Explanation of symbols]

1 shaft 2 elastic layer 3 outermost resin layer 4 Intermediate resin layer 5 Photosensitive drum (latent image holder) 6 Developing roller (developing member) 7 Developing device 8 Transfer paper 9 Transfer roller (transfer member) 11 Cleaning roller (cleaning member) 12 Cleaning device 13 Fixer

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 15/16 103 G03G 15/16 103 21/10 C08L 27:12 // (C08L 75/04 G03G 21/00 312 27 : 12) F-term (reference) 2H071 BA43 DA08 DA09 DA13 2H077 AD06 EA15 FA12 FA22 FA27 2H134 HA01 HA02 HA03 HA05 HA17 HB20 KD04 2H200 GA49 HA02 HB12 HB22 HB45 HB46 HB47 JA01 MB01 MC05 MC08 NA01 4J002 BD2 043CK152BD1 GQ00

Claims (10)

[Claims] 1. A conductive member used in an electrophotographic apparatus, comprising an elastic layer and at least one formed on the elastic layer.
The outermost resin layer constituting the surface of the member comprises a urethane modified acrylic resin of 50% by weight or more and a fluorine resin component and / or a fluorine compound component of 50% by weight or less. A voltage of 8 kV is applied to a corona discharger arranged at a distance of 1 mm from the surface of the outermost resin layer, which is a conductive member made of a resin material and in which the outermost resin layer contains no conductive agent. When the outermost resin layer surface was charged by applying a corona discharge by applying the voltage, the maximum value of the surface potential after 0.3 seconds was 50%.
A conductive member having a voltage of V or less and a surface potential of 5 V or less after 10 seconds. 2. The content of urethane-modified acrylic resin in the resin material forming the outermost resin layer is 50 to 99.9% by weight, and the fluorine resin component and / or the fluorine compound component is 0.1 to 50% by weight. The conductive member according to claim 1, wherein 3. The conductive member according to claim 1, wherein the urethane modified acrylic resin contains a silicone component in an amount of 1 to 60% by weight. 4. Cellulose 100%, 30 g / m ² , 7
The friction coefficient with respect to the cloth of 0 mesh is 0.5 or less when the cloth is pressed against the cloth with a load of 100 gf.
The conductive member according to any one of 1 to 3. 5. The contact angle of the outermost resin layer surface with water is 9
The conductive member according to any one of claims 1 to 4, which is at least 0 degree. 6. The resin material forming the outermost resin layer comprises:
A bifunctional or higher functional isocyanate crosslinking agent is contained.
The conductive member according to any one of items 1 to 5. 7. A resin material for molding the outermost resin layer,
The conductive member according to any one of claims 1 to 6, which contains a conductive powder. 8. A developer is carried on the surface of the conductive member according to claim 1 to form a thin film of the developer, and the electrostatic latent image is held on the surface in this state. An electronic device comprising a developing device for visualizing the electrostatic latent image by bringing the developer into contact with the latent image carrier to adhere the developer to the electrostatic latent image on the surface of the latent image carrier. Photographic equipment. 9. A transfer device for charging the transfer paper with the conductive member according to claim 1, and transferring the developer from the electrostatic latent image visualized by the developer onto the transfer paper. An electrophotographic apparatus characterized by the following. 10. An electrophotographic apparatus comprising a cleaning device for removing the developer remaining on the latent image holding member by the conductive member according to claim 1. Description: