JP5994322B2 - Method for manufacturing charging member - Google Patents

Description

  The present invention relates to a charging member, a charging device, a process cartridge, and a pixel forming apparatus.

  An image forming apparatus using an electrophotographic method, for example, charges a surface of a photosensitive member by bringing a charging roll into contact with an image holding member (photosensitive member), and forms an electrostatic latent image using a laser or the like that modulates an image signal. Thereafter, the electrostatic latent image is developed with a developer containing toner to form a toner image. A transferred image is obtained by electrostatically transferring the toner image to the recording material medium via an intermediate transfer member.

  Regarding the charging roll, for example, in Patent Document 1, 10 to 50 parts by mass of a sulfur-free and chlorine-free sub is contained with respect to 100 parts by mass of the rubber component containing epichlorohydrin rubber copolymerized with allyl glycidyl ether. The vulcanizing agent contains 1 to 3 parts by mass of dipentamethylene thiuram tetrasulfide, 1 to 3 parts by mass of a thiuram disulfide compound and 0.5 to 1.5 parts by mass of a morpholinodithio compound, and the amount of sulfur added is 0. A conductive rubber composition characterized in that it is 2 parts by mass or less and a conductive roller whose elastic layer is made of a vulcanized product of the conductive rubber composition are disclosed.

  In Patent Document 2, in a conductive rubber roller in which a rubber layer is formed on a conductive core material, the rubber material of the rubber layer is acrylonitrile butadiene rubber, epichlorohydrin rubber, polyethylene oxide-polypropylene oxide-allyl glycidyl ether ternary copolymer. When composed of a polymer and the total mass is 100, the total of thiuram accelerator (A) and thiazole accelerator (B) for the rubber material is 1.0 part by mass <A + B <5.0 parts by mass And a conductive rubber roller characterized in that the mass ratio is 1.0 <A / B <4.5.

JP 2002-173594 A JP 2006-58537 A

  An object of the present invention is to provide a charging member having an elastic layer in which variation in vulcanization is suppressed.

In order to achieve the above object, the following invention is provided.
The invention according to claim 1, on a conductive support, epichlorohydrin - ethylene oxide - with allyl glycidyl ether copolymer rubber, of at least one organic vulcanizing agent and at least one vulcanization accelerator vulcanization system the rubber composition comprising a blend, wherein the epichlorohydrin - ethylene oxide - respective reaction starting temperature determined from vulcanization curve of each one of allyl glycidyl ether copolymer rubber and the vulcanizing system formulation, the rubber The pre-vulcanization temperature before vulcanizing the composition and the vulcanization temperature when vulcanizing the rubber composition satisfy the following formula (1), and each one of the vulcanized compounds: A process of forming an elastic layer by vulcanization under the condition that the melting point of the above satisfies the following formula (2):
The manufacturing method of the charging member which has this.
Formula (1): Pre-vulcanization temperature <reaction initiation temperature <vulcanization temperature Formula (2): Melting point of vulcanized compound <vulcanization temperature In the invention of claim 2, the organic vulcanizing agent is organic sulfur. The method for producing a charging member according to claim 1, wherein the charging member is a vulcanizing agent.
The invention according to claim 3, wherein the rubber composition, before Symbol include 4,4'-dithiodimorpholine as organic vulcanizing agent, thiazole vulcanization accelerators and thiuram vulcanization accelerator as the vulcanization accelerator The manufacturing method of the charging member of Claim 1 or Claim 2 containing this.

According to invention of Claim 1, the manufacturing method of the charging member which has an elastic layer by which the variation in vulcanization | cure was suppressed compared with the case where an elastic layer does not satisfy | fill said Formula (1) and (2) is provided.
According to the invention of claim 3, wherein the rubber composition is epichlorohydrin - ethylene oxide - compared with a case that does not contain the above any one as allyl glycidyl ether copolymer rubber及 beauty vulcanization formulation, vulcanized variation A method for producing a charging member having an elastic layer in which the suppression is suppressed is provided.

It is a figure which shows an example of the vulcanization curve of the test based on JISK6300-2. It is a schematic sectional drawing which shows an example of the charging member which concerns on this embodiment. It is a schematic sectional drawing which shows the other example of the charging member which concerns on this embodiment. It is a schematic block diagram which shows an example of the charging device provided with the charging member which concerns on this embodiment. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an exemplary embodiment. It is a schematic block diagram which shows the other example of the image forming apparatus which concerns on this embodiment. It is a schematic block diagram which shows the other example of the image forming apparatus which concerns on this embodiment. It is a schematic block diagram which shows an example of the process cartridge which concerns on this embodiment.

  Hereinafter, embodiments of a charging member, a charging device, a process cartridge, and an image forming apparatus according to the present invention will be described in detail.

[Charging member]
The charging member according to the present embodiment includes a conductive support, it is disposed on the conductive support, epichlorohydrin - ethylene oxide - with allyl glycidyl ether copolymer rubber, of at least one organic vulcanizing agent and at least one a species of the vulcanization and accelerator consisting agent vulcanization formulation, elastic layer formed by vulcanizing the rubber composition containing the epichlorohydrin - ethylene oxide - the allyl glycidyl ether copolymer rubber vulcanizing Each reaction start temperature obtained from a vulcanization curve with one of each of the vulcanized compounds, a temperature before vulcanization of the rubber composition, and a vulcanization when the rubber composition is vulcanized The hourly temperature satisfies the following formula (1), and each of the vulcanized compounds has an elastic layer in which one melting point satisfies the following formula (2).
Formula (1): Pre-vulcanization temperature <reaction start temperature <vulcanization temperature Formula (2): Melting point of vulcanized compound <vulcanization temperature The charging member according to the present embodiment has the above-described configuration. The variation in vulcanization in the elastic layer is suppressed. The reason why the variation in vulcanization in the elastic layer is suppressed is assumed as follows.

  For example, an elastic layer of a charging roll that is an example of a charging member is widely made of a rubber material. In forming the elastic layer, the raw materials such as rubber materials are generally kneaded, molded, vulcanized, and polished. In the vulcanization step, heat is applied to the rubber raw material and each compounding agent, so that the rubber raw material is made into a rubber elastic body by a crosslinking reaction. For crosslinking reaction, sulfur crosslinking (vulcanization) is widely used.

Originally, it is desirable to vulcanize at a desired temperature condition in the vulcanization process, but the rubber raw material and each compounding agent are also subjected to heat stress in the kneading and molding processes which are the previous processes. In kneading, each rubber compounding material is mixed and dispersed by applying shearing force to the rubber raw material and each compounding agent, so the kneading material generates heat and the temperature rise is avoided even if it is cooled. Absent.
Generally, the temperature at the time of kneading is the rubber temperature at the time of kneading. From the rubber vulcanization characteristics of the kneaded product of the rubber raw material and each compounding agent according to the vibration vulcanization tester described in JIS K6300-2, However, it is confirmed that it is not vulcanized at the kneading temperature, that is, there is no change in torque. However, the temperature inside the kneaded rubber is usually higher than that near the surface that can be monitored, and the vulcanization characteristics of the rubber raw material and the single vulcanized material (vulcanized compound) Unlike the vulcanization characteristics of the whole product, vulcanization may start at a low temperature. That is, a part of the vulcanized material may react alone with the rubber component before the vulcanization step such as the kneading step.

  When vulcanization with a part of the vulcanized material is started, the vulcanization state is different between a portion where vulcanization is started and a portion where vulcanization is slow. Moreover, the blending balance of the vulcanized materials is lost, and the vulcanization reaction by the originally intended blending cannot be obtained. When a vulcanization reaction different from the target occurs in this way, variations in electrical resistance and hardness, bleed and bloom in which the compound and its reaction by-products precipitate on the surface of the elastic layer, deterioration of compression set, and the like occur. Such deterioration (defects) in the characteristics of the elastic layer is largely caused by rubber vulcanization.

  Also in the molding process, although it varies depending on the method, it is affected by the thermal history, and the method of performing molding and vulcanization in separate processes has a great influence. In the molding process, it is necessary to plasticize the rubber kneaded material to some extent by heat. The temperature for plasticization is set lower than the vulcanization start temperature of the rubber kneaded product, but since rubber generates a large amount of heat due to shearing, the rubber kneaded product is locally or temporarily higher than the plasticizing temperature at the time of molding. May become hot. For example, when a rubber kneaded material is moved, filling a mold, shearing with a screw, passing through a narrow flow path such as a die. When unintentional vulcanization with a part of the vulcanized material starts with such heat generation, the rubber kneaded product increases in viscosity over time, causing defects in the molding process.

On the other hand, in this embodiment, epichlorohydrin - ethylene oxide - to temperature at which the reaction is initiated with the respective one of allyl glycidyl ether copolymer rubber and vulcanizing formulation (reaction starting temperature), the rubber composition mixing step The temperature before the vulcanization process such as the molding process (temperature before vulcanization) is lowered, and the temperature in the vulcanization process (temperature during vulcanization) is increased. That is, by satisfying the formula (1), unintentional vulcanization by a part of the vulcanized material before the vulcanization process is suppressed, and in the vulcanization process, each vulcanized compound is sufficiently combined with the rubber component. The reaction will result in vulcanization.

In addition, by setting the vulcanization temperature higher than the melting point of each vulcanization compound, that is, by satisfying the above formula (2), the vulcanization compound becomes liquid at the time of vulcanization and becomes uniform in the rubber. In addition, the vulcanization is carried out over a wide range and substantially uniformly.
That is, it is considered that the variation in vulcanization is effectively suppressed by forming the elastic layer so as to satisfy the formulas (1) and (2). And by using the charging member having the elastic layer formed in this way, variations in electrical resistance and hardness, bleed and bloom, and deterioration of compression set are suppressed, and an image forming apparatus provided with such a charging member By forming an image with, image defects such as image unevenness and streaks that are considered to be caused by variations in vulcanization of the elastic layer are suppressed.

(Layer structure)
As long as the charging member according to the present embodiment includes a conductive support and at least an elastic layer formed on the conductive support, the layer configuration is not particularly limited. For example, other layers such as one or more intermediate layers and surface layers may be formed on the outer peripheral surface of the elastic layer. In addition, a conductive agent may be added to the constituent material in order to obtain a desired electrical resistance for each layer.

  Hereinafter, as an example of the charging member according to this embodiment, the conductive support of the charging roll, the adhesive layer, the elastic layer, the surface layer, and the like will be described in more detail. The constituent materials of these layers are charged in other shapes. You may use similarly about a member.

FIG. 2 is a schematic configuration diagram illustrating a cross section in a direction (radial direction) perpendicular to the axis of the charging roll according to the present embodiment. A charging roll 30 </ b> A shown in FIG. 2 includes an adhesive layer 32, an elastic layer 33, and a surface layer 35 in this order on a conductive support 31.
FIG. 3 shows another example of the charging roll according to this embodiment. The charging roll 30B shown in FIG. 3 includes an adhesive layer 32, an elastic layer 33, an intermediate layer 34, and a surface layer 35 in this order on a conductive support 31.

(Conductive support)
The conductive support 31 functions as an electrode and a support member of the charging member (charging rolls 30A and 30B). “Conductivity” in the conductive support 31 means that the resistance value is 1 × 10 ⁴ Ω or less, and examples of the conductive support 31 include metals such as aluminum, copper alloy, and stainless steel, or alloys. An iron plated with chromium, nickel or the like, for example, a free cutting steel as shown in JIS G4804 made of a material plated with chromium, nickel or the like is used. The plating may be formed by an electrolytic plating method or an electroless plating method, and is not limited.

(Adhesive layer)
The material for forming the adhesive layer 32 is not particularly limited as long as it is a material that adheres to the conductive support 31 and the elastic layer 33, for example, polyolefin, chlorine rubber, acrylic, epoxy, polyurethane, nitrile. Rubber type, vinyl chloride type, vinyl acetate type, polyester type, phenol type, silicone type and the like are used. From the viewpoint of adhesiveness with the vulcanized rubber composition forming the elastic layer 33, polyolefin and phenol are particularly desirable.
The adhesive layer 32 may have a single layer configuration or a combination of a plurality of layers.

  The adhesive layer 32 is made of carbon black such as conductivity imparted ketjen black or acetylene black; pyrolytic carbon, graphite; various conductive metals or alloys such as aluminum, copper, nickel, stainless steel; tin oxide, indium oxide. , Titanium oxide, tin oxide-antimony oxide solid solution, various conductive metal oxides such as tin oxide-indium oxide solid solution; conductive materials on the surface of insulating materials; powders, polymer materials such as liquid rubber added You may do it.

(Elastic layer)
The elastic layer 33, epichlorohydrin - ethylene oxide - with allyl glycidyl ether copolymer rubber, a rubber composition containing a vulcanizing system formulation comprising at least one organic vulcanizing agent and at least one vulcanization accelerator It is formed by vulcanization (crosslinking). Then, the elastic layer 33, the epichlorohydrin - ethylene oxide - allyl glycidyl ether copolymer rubber and the vulcanizing system formulation of each of the reaction initiation temperature determined from vulcanization curve of each one, the rubber composition The pre-vulcanization temperature before vulcanization and the vulcanization temperature when vulcanizing the rubber composition satisfy the following formula (1), and each of the vulcanization-type compounds has a melting point of It forms so that Formula (2) may be satisfy | filled.
Formula (1): Pre-vulcanization temperature <reaction initiation temperature <temperature at vulcanization Formula (2): Melting point of vulcanized compound <temperature at vulcanization

- epichlorohydrin - ethylene oxide - allyl glycidyl ether copolymer rubber -
The elastic layer in this embodiment, as unvulcanized rubber materials, epichlorohydrin having the main chain and / or side chain double bonds - using allyl glycidyl ether copolymer rubber - ethylene oxide.
In particular, epichlorohydrin-ethylene oxide-allyl glycidyl ether copolymer rubber is desirable from the viewpoint of resistance uniformity for a charging roll that requires semiconductivity. Other desirable materials include isoprene rubber, chloroprene rubber, styrene-butadiene rubber, butadiene rubber, acrylonitrile-butadiene copolymer rubber (NBR), natural rubber, and blended rubbers thereof.

The rubber composition used in this embodiment, the unvulcanized epichlorohydrin - ethylene oxide - as allyl glycidyl ether copolymer rubber vulcanization (crosslinking) is to vulcanization formulations, at least one organic vulcanizing agent and at least Contains one vulcanization accelerator. For the purpose of promoting the function of the vulcanizing agent, a vulcanization accelerating aid such as zinc oxide and stearic acid may be included, but the vulcanizing accelerating agent itself is combined with a rubber component to form a crosslinked structure. It is not included, and is not included in the vulcanized compound in this embodiment.

-Organic vulcanizing agent-
As a vulcanizing agent used for forming the elastic layer in the present embodiment, an organic vulcanizing agent such as organic sulfur is used instead of an inorganic substance such as inorganic sulfur. Organic sulfur tends to have a higher reaction initiation temperature with the rubber component than inorganic sulfur, and the relationship of formula (1) is satisfied.
Examples of the organic vulcanizing agent include 4,4′-dithiodimorpholine, dipentamethylene thiuram tetrasulfide, and the like. In order to function stably as a vulcanizing agent regardless of the formulation, the function as a vulcanization accelerator is Low 4,4′-dithiodimorpholine is desirable.

The amount of the organic vulcanizing agent is not particularly limited, addition of the organic vulcanizing agent, epichlorohydrin - ethylene oxide - allyl glycidyl ether copolymer rubber, it is sufficient be selected according to the type of vulcanization accelerator, bleeding, Bloom, and in view of compression set, the amount of the vulcanizing agent is epichlorohydrin - ethylene oxide - preferably not more than 5 parts by mass or more 0.5 parts by mass with respect to allyl glycidyl ether copolymer rubber 100 parts by weight.

-Vulcanization accelerator-
Vulcanization of the rubber component is possible with only a vulcanizing agent, but a vulcanization accelerator is necessary for sufficient vulcanization and shortening of the vulcanization time. In order to develop the desired vulcanization characteristics, several kinds of vulcanization accelerators may be combined.

  Vulcanization accelerators include aldehyde-ammonia, aldehyde-amine, thiourea, guanidine, thiazole, sulfenamide, thiuram, dithiocarbamate, and xanthate. In order to achieve high productivity, it is desirable to use thiazole and thiuram in combination. Further, it is desirable that the dithiocarbamate system has the same structure as the thiuram system.

  Examples of thiazole vulcanization accelerators include 2-mercaptobenzothiazole, di-2-benzothiazolyl disulfide, zinc salt of 2-mercaptobenzothiazole, cyclohexylamine salt of 2-mercaptobenzothiazole, 2- (N, N -Diethylthiocarbamoylthio) benzothiazole, 2- (4′-morpholinodithio) benzothiazole and the like, and di-2-benzothiazolyl disulfide is desirable.

  Examples of the thiuram vulcanization accelerator include tetramethyl thiuram monosulfide, tetramethyl thiuram disulfide, tetraethyl thiuram disulfide, tetrabutyl thiuram disulfide, dipentamethylene thiuram tetrasulfide, tetrabenzyl thiuram disulfide and the like. Tetramethylthiuram disulfide and tetraethylthiuram disulfide are desirable from the viewpoint of vulcanization start temperature, vulcanization speed, bleed, bloom, and compression set.

The blending amount of the vulcanization accelerator is not particularly limited, but from the viewpoint of bleed, bloom, and compression set, the blending amount of the vulcanization accelerator is preferably 2 to 4 times (mass ratio) of the vulcanizing agent.
In the case of using a thiazole type and a thiuram type together as a vulcanization accelerator, the amount of the thiazole type is preferably 0.8 to 2 times (mass ratio) of the thiuram type.

-Conductive agent-
The rubber composition for forming the elastic layer according to this embodiment may contain a conductive agent. As the conductive agent, an electronic conductive agent or an ionic conductive agent is used.
Examples of electronic conductive agents include carbon blacks such as ketjen black and acetylene black; pyrolytic carbon, graphite; various conductive metals or alloys such as aluminum, copper, nickel, and stainless steel; tin oxide, indium oxide, titanium oxide And various conductive metal oxides such as tin oxide-antimony oxide solid solution and tin oxide-indium oxide solid solution;

Examples of ionic conductive agents include perchlorates and chlorates such as tetraethylammonium and lauryltrimethylammonium; alkali metals such as lithium and magnesium; perchlorates and chlorates of alkaline earth metals ;
In addition, a electrically conductive agent may be used independently and may be used in combination of 2 or more type.

  The amount of the conductive agent added is not particularly limited, but in the case of the electronic conductive agent, the amount is preferably in the range of 1 part by mass to 30 parts by mass with respect to 100 parts by mass of the rubber component. It is more desirable that the range be 25 parts by mass or less. On the other hand, in the case of the ionic conductive agent, it is desirable that it is in the range of 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the rubber component, and 0.5 to 3.0 parts by mass. The following range is more desirable.

-Pre-vulcanization temperature-
And before vulcanization temperature in the present embodiment, epichlorohydrin - and the allyl glycidyl ether copolymer rubber, of at least one organic vulcanizing agent and at least one vulcanization accelerator vulcanization formulation - ethylene oxide It is the temperature which the rubber composition containing contains before the vulcanization process. The temperature before vulcanization is usually the highest during the kneading of the rubber composition. In this embodiment, the temperature during the kneading of the rubber composition may be regarded as the temperature before vulcanization. Specifically, the temperature may be measured by inserting a thermometer into the rubber kneaded material immediately after the kneading.

  In addition, when the temperature is higher when the rubber kneaded material is filled into a mold, sheared by a screw, or passed through a narrow channel such as a die, the temperature at these stages is higher than the temperature at the time of kneading. Is measured as the pre-vulcanization temperature.

In the present embodiment, the vulcanization temperature, epichlorohydrin - ethylene oxide - lower than the reaction starting temperature of the allyl glycidyl ether copolymer rubber and a vulcanizing system formulation alone. Before vulcanization temperature, rubber epichlorohydrin contained in the composition - ethylene oxide - Depending on the combination of allyl glycidyl ether copolymer rubber and vulcanizing formulation, ensuring unintended vulcanization before the vulcanization process From the viewpoint of suppression, it is desirably 20 ° C. or more lower than the reaction start temperature of the vulcanized compound, and more desirably 30 ° C. or more.
For example, cooling during kneading is performed at a lower temperature. In particular, cooling while thinning rubber with an open roll is preferable because of high cooling efficiency. In addition, the temperature before vulcanization can be kept low by previously cooling the material before kneading.

-Turning temperature-
The vulcanization temperature in the present embodiment is the temperature of the rubber composition when the rubber composition is heated and crosslinked. For example, the kneaded rubber composition is vulcanized (crosslinked) with a molding machine. In this case, the temperature of the mold may be regarded as the vulcanization temperature. Alternatively, when the kneaded rubber composition is molded and then heated by a heating means such as an oven to be vulcanized (crosslinked), the heating temperature by the heating means may be regarded as the vulcanization temperature.

-Reaction start temperature of vulcanized compound-
The reaction starting temperature of vulcanization formulations in this embodiment, the unvulcanized epichlorohydrin - ethylene oxide - to a mixture of respectively singly allyl glycidyl ether copolymer rubber and vulcanizing formulation, JISK6300- The test is performed using the vibration vulcanization tester described in 2, and is obtained based on the vulcanization curve.
FIG. 1 shows an example of a vulcanization curve based on a test using a vibration vulcanization tester described in JIS K6300-2 for a rubber composition. In FIG. 1, MH represents the maximum torque, ML represents the minimum torque, ME represents the difference between the maximum torque and the minimum torque (MH-ML), and t90 represents the time for the torque to reach 90% ME. When a torque is applied to the rubber composition in the present embodiment while being heated at a constant temperature, as shown in FIG. 1, the torque decreases to reach the minimum torque (ML) in the initial stage, and the time elapses. Along with this, vulcanization (crosslinking) proceeds and the torque starts to increase, and when the crosslinking is completed, the maximum torque (MH) is reached.

Epichlorohydrin - ethylene oxide - to a mixture of allyl glycidyl ether copolymer rubber and (unvulcanized) respectively one single vulcanization formulation, tested by oscillating vulcanization tester according to JISK6300-2 If the, the temperature and time reaction is initiated by the type of curing system formulation are different, vulcanizing formulation using epichlorohydrin - ethylene oxide - heated at a temperature above that reacts with allyl glycidyl ether copolymer rubber By continuing to apply torque in this state, the reaction (crosslinking) starts, and an increase in torque is observed in the vulcanization curve as shown in FIG.

Epichlorohydrin - ethylene oxide - to a mixture of the respective singly allyl glycidyl ether copolymer rubber and vulcanizing formulation, except for changing the heating temperature was measured vulcanization characteristics under the same conditions, the torque is continuously The temperature when starting to rise is recognized as the reaction start temperature of the vulcanized compound. For example, when the rubber composition used in the present embodiment contains two or more vulcanization accelerators, the reaction start temperature is measured for each vulcanization accelerator. The same applies when two or more organic vulcanizing agents are included.

The reaction starting temperature of the vulcanization system formulation in the present embodiment are merely qualitative, epichlorohydrin if it is possible to identify the reaction starting temperature by the test based on JISK6300-2 - ethylene oxide - allyl glycidyl ether copolymer rubber There are no particular restrictions on the amount of the vulcanized compound blended. For example, in order to reflect the vulcanization characteristics of each vulcanization compound in the rubber composition used for forming the elastic layer, an epichlorohydrin-ethylene oxide-allyl glycidyl ether copolymer rubber contained in the rubber composition used for forming the elastic layer is used. What is necessary is just to employ | adopt the compounding quantity of each vulcanization-type compound with respect to the system, respectively.

In addition, when calculating | requiring the reaction start temperature of each vulcanization | cure type | system | group compound in this embodiment, reaction (bridge | crosslinking) does not start in the elapsed time similar to the rubber composition for forming an elastic layer, but a vulcanization type The time at which the reaction starts varies depending on the type of the compound, and the reaction may start after a time longer than the time at which the reaction of the rubber composition starts.
Kneading time when obtaining the reaction starting temperature of the vulcanization system formulation in the present embodiment, epichlorohydrin - ethylene oxide - may be appropriately set according to the type of allyl glycidyl ether copolymer rubber and vulcanizing system formulation However, for example, in the case where the rubber composition is kneaded while being heated and cross-linked, if the time until reaching 90% ME (tc90) shown in FIG. Therefore, in the present embodiment, when determining the reaction start temperature of each vulcanized compound, kneading is carried out until a time 10 times tc90 in the vulcanization characteristics of the rubber composition, during which the torque starts to rise continuously. The temperature at this time may be the reaction start temperature of the vulcanized compound. For example, the vulcanization curve shown in FIG. 1 certifies that the reaction has started at time A.

  In addition, since the reaction start temperature does not depend on the blending amount of the vulcanized material, the elastic layer after crosslinking the rubber composition usually has an unreacted vulcanized compound remaining. The reaction initiation temperature can be measured by extracting from the cross section of the elastic layer and specifying each vulcanization compound.

-Thickness-
The thickness of the elastic layer 33 is not particularly limited and may be selected according to the application. For example, when the charging roll used for charging the electrophotographic photosensitive member (image holding member) in the image forming apparatus is set to 0.5 mm to 5 mm.

(Middle layer)
The intermediate layer 34 is provided as necessary for resistance adjustment when the electric resistance of the elastic layer 33 is low. Although it does not restrict | limit especially as a polymeric material at the time of comprising the intermediate | middle layer 34, Epichlorohydrin- ethylene oxide-allyl glycidyl ether copolymer rubber is desirable. Other desirable materials include isoprene rubber, chloroprene rubber, styrene-butadiene rubber, butadiene rubber, acrylonitrile-butadiene copolymer rubber (NBR), natural rubber, and blended rubbers thereof.

(Surface layer)
The surface layer 35 prevents the surface of the charging member from being contaminated by a developer component, paper powder, or the like when used in a bleed-out block of a composition from an inner layer such as an elastic layer or an intermediate layer, or in an electrophotographic apparatus. Therefore, it is provided as necessary, and is formed from a composition obtained by mixing a conductive material and various particles with a polymer material.
The polymer material constituting the surface layer 35 is not particularly limited. For example, polyamide, polyurethane, polyvinylidene fluoride, tetrafluoroethylene copolymer, polyester, polyimide, silicone resin, acrylic resin, polyvinyl butyral, ethylene tetrafluoroethylene Examples thereof include copolymers, melamine resins, fluororubbers, epoxy resins, polycarbonates, polyvinyl alcohol, cellulose, polyvinylidene chloride, polyvinyl chloride, polyethylene, and ethylene vinyl acetate copolymers.

  The above polymer materials may be used alone or in combination of two or more. The number average molecular weight of the polymer material is preferably in the range of 1,000 to 100,000, and more preferably in the range of 10,000 to 50,000.

Examples of the conductive agent that can be included in the surface layer 35 include a conductive agent used for the elastic layer 33.
Examples of the particles that can be included in the surface layer 35 include metal oxides such as silicon oxide, aluminum oxide, and barium titanate, or composite metal oxides, and polymer powders such as tetrafluoroethylene and vinylidene fluoride. However, it is not particularly limited to these.

  The addition amount of the conductive agent and various particles in the surface layer 35 is not particularly limited, but is preferably in the range of 1 part by mass to 50 parts by mass with respect to 100 parts by mass of the polymer material. It is more desirable that the amount be in the range of parts by mass or less.

  Next, a charging device, a process cartridge, and an image forming apparatus including the charging roll according to the present embodiment will be described.

[Charging device]
The charging device according to the present embodiment is not particularly limited as long as it includes a charging roll having the elastic layer 33 described above. FIG. 4 is a schematic configuration diagram illustrating an example of a charging device including the charging roll according to the present embodiment. The charging device 100 according to the present embodiment includes a charging roll 30 for charging a member to be charged (for example, an image carrier), and a cleaning roll 40 disposed in contact with the outer peripheral surface of the charging roll 30. .
In the charging device 100 according to this embodiment, the member to be charged (for example, the image holding member) is charged by the charging roll 30 while the surface of the charging roll 30 is cleaned by the cleaning roll 40.

The charging roll 30 has the elastic layer 33 described above on a conductive support 31.
The cleaning roll 40 has an outer peripheral surface formed as an elastic layer made of rubber or the like. For example, the cleaning roll 40 may be in contact with the outermost layer of the charging roll 30 in a freely detachable state. When the cleaning roll 40 comes into contact with the charging roll 30, the cleaning roll 40 is disposed in a state of being pressed against the charging roll 30, and rotates with the rotation of the charging roll 30. Thereby, generation | occurrence | production of the scratches to the charging roll 30 etc. is prevented.

  The cleaning roll 40 may be installed so as to be reciprocally movable in the axial direction of the charging roll 30. Thereby, when cleaning is not required (for example, when the image forming apparatus is stopped for a long time), the cleaning roll 40 is placed away from the charging roll 30, and the surface of the charging roll 30 is substantially Clean evenly.

[Image forming apparatus]
An image forming apparatus according to the present embodiment includes an image holding member and the above-described charging member, and charging means that charges the surface of the image holding member by bringing the charging member into contact with the surface of the image holding member. An electrostatic latent image forming unit that forms an electrostatic latent image on the surface of the charged image carrier, and a toner image obtained by developing the electrostatic latent image formed on the surface of the image carrier with a developer containing toner. Developing means, transfer means for transferring the toner image formed on the surface of the image carrier to a recording medium, and fixing means for fixing the toner image transferred to the recording medium.

(First embodiment)
FIG. 5 is a cross-sectional view schematically showing a basic configuration of the image forming apparatus according to the first embodiment. An image forming apparatus 200 shown in FIG. 5 includes an electrophotographic photosensitive member 207 as an image holding member, a charging device 208 that charges the electrophotographic photosensitive member 207, a power source 209 connected to the charging device 208, and a charging device 208. An exposure device 206 that exposes a charged electrophotographic photosensitive member 207 to form a latent image, a developing device 211 that develops the latent image formed by the exposure device 206 with toner, and forms a toner image, and a developing device 211 A transfer device 212 that transfers the toner image formed by the above to a recording medium (image output medium) 500, a cleaning device 213 that removes residual toner and the like on the electrophotographic photosensitive member 207, and a static eliminator 214 that removes residual charges. And a fixing device 215 for fixing the toner image transferred to the recording medium. In some cases, the static eliminator 214 is not provided.

  The charging device 208 is of a type (contact charging method) in which a charging roll is brought into contact with the surface of the electrophotographic photosensitive member 207 to charge the surface of the photosensitive member 207, and the above-described charging device of this embodiment is used. .

  As the exposure apparatus 206, an optical system apparatus that exposes a light source such as a semiconductor laser, an LED (light emitting diode), and a liquid crystal shutter on the surface of the electrophotographic photosensitive member 207 in a desired image-like manner is used.

The developing device 211 contains a developer containing toner.
The toner includes, for example, a binder resin and a colorant. Examples of the binder resin include homopolymers and copolymers such as styrenes, monoolefins, vinyl esters, α-methylene aliphatic monocarboxylic acid esters, vinyl ethers, vinyl ketones, and the like. As the binder resin, polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyethylene And polypropylene. Furthermore, polyester, polyurethane, epoxy resin, silicone resin, polyamide, modified rosin, paraffin wax, and the like can also be mentioned.

  Coloring agents include magnetic powders such as magnetite and ferrite, carbon black, aniline blue, calcoil blue, chrome yellow, ultramarine blue, dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, and lamp black. Rose Bengal, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 57: 1, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 17, C.I. I. Pigment blue 15: 1, C.I. I. Pigment Blue 15: 3 is a typical example.

  The toner may be internally added or externally added with known additives such as a charge control agent, a release agent, and other inorganic particles.

Typical examples of the release agent include low molecular weight polyethylene, low molecular weight polypropylene, Fischer-Tropsch wax, montan wax, carnauba wax, rice wax, and candelilla wax.
Known charge control agents are used, but azo metal complex compounds, metal complex compounds of salicylic acid, and resin type charge control agents containing polar groups are used.

  As other inorganic particles, small-diameter inorganic particles having an average primary particle size of 40 nm or less are used for the purpose of powder flowability, charge control, etc., and if necessary, larger diameters are used to reduce adhesion. These inorganic or organic particles may be used in combination. As these other inorganic particles, known ones are used.

  In addition, the surface treatment of the small-diameter inorganic particles is effective because the dispersibility becomes high and the effect of increasing the powder fluidity increases.

  As a method for producing the toner used in the exemplary embodiment, a polymerization method such as an emulsion polymerization aggregation method or a dissolution suspension method is desirably used because high shape controllability can be obtained. In addition, a manufacturing method may be performed in which the toner obtained by the above method is used as a core, and agglomerated particles are further adhered and heat-fused to give a core-shell structure.

  When the external additive is added, the toner and the external additive are mixed by a Henschel mixer or a V blender. In addition, when the toner is manufactured by a wet method, the toner may be added by a wet method.

  Note that the developer used in this embodiment may be a one-component system including only toner, or a two-component system including toner and carrier.

  The transfer device 212 is capable of supplying a current having a predetermined current density toward the electrophotographic photosensitive member when the toner image formed on the electrophotographic photosensitive member 207 is transferred to the recording medium 500. Is desirable.

  The cleaning device 213 is for removing residual toner adhering to the surface of the electrophotographic photosensitive member after the transfer process. The cleaned electrophotographic photosensitive member is repeatedly used for the image forming process described above. . As the cleaning device 213, in addition to a cleaning blade, brush cleaning, roll cleaning, and the like are used. Among these, it is desirable to use a cleaning blade. Examples of the material for the cleaning blade include urethane rubber, neoprene rubber, and silicone rubber.

  Further, the image forming apparatus of the present embodiment may further include a static eliminator 214 as shown in FIG. The neutralization device 214 performs neutralization by irradiating the electrophotographic photosensitive member 207 after transferring the toner image with light. As a result, when the electrophotographic photosensitive member is repeatedly used, the phenomenon that the residual potential of the electrophotographic photosensitive member 214 is brought into the next cycle is prevented, so that the image quality is further improved.

(Second Embodiment)
FIG. 6 is a cross-sectional view schematically showing the basic configuration of the image forming apparatus according to the second embodiment. The image forming apparatus 210 shown in FIG. 6 applies an intermediate transfer method, and after transferring the toner image formed on the electrophotographic photosensitive member 207 to the primary transfer member (intermediate transfer member) 212a, the primary transfer is performed. An intermediate transfer type transfer device for transferring to a recording medium (image output medium) 500 supplied between the member 212a and the secondary transfer member 212b is provided. A current having a predetermined current density can be supplied toward the photoconductor 207. Although not shown in FIG. 6, the image forming apparatus 210 may further include a static eliminator as in the image forming apparatus 200 shown in FIG. Other configurations of the image forming apparatus 210 are the same as those of the image forming apparatus 200.

(Third embodiment)
FIG. 7 is a cross-sectional view schematically showing a basic configuration of an image forming apparatus according to the third embodiment. An image forming apparatus 220 shown in FIG. 7 is an intermediate transfer type image forming apparatus. In the housing 400, four electrophotographic photosensitive members 401a to 401d (for example, the electrophotographic photosensitive member 401a is yellow and the electrophotographic photosensitive member 401b is magenta). The electrophotographic photosensitive member 401c can form an image of cyan and the electrophotographic photosensitive member 401d can form a black color) are arranged in parallel along the intermediate transfer belt 409.

  The electrophotographic photoconductors 401a to 401d mounted on the image forming apparatus 220 include, for example, hydroxygallium phthalocyanine having a maximum peak wavelength in a range of 810 nm to 839 nm in a spectral absorption spectrum in a wavelength region of 600 nm to 900 nm. An electrophotographic photoreceptor having a photosensitive layer to be contained is employed.

Each of the electrophotographic photosensitive members 401a to 401d can be rotated in a predetermined direction (counterclockwise on the paper surface), and charging rolls 402a to 402d, developing devices 404a to 404d, and primary transfer rolls along the rotation direction. 410a to 410d and cleaning blades 415a to 415d are arranged. Each of the developing devices 404a to 404d can supply toners of four colors of black, yellow, magenta, and cyan accommodated in toner cartridges 405a to 405d. These toners satisfy, for example, the condition that the average shape factor is 100 or more and 140 or less.
The primary transfer rolls 410a to 410d are disposed so as to be in contact with the electrophotographic photosensitive members 401a to 401d via the intermediate transfer belt 409, respectively.

  Further, a laser light source (exposure device) 403 is disposed at a predetermined position in the housing 400, and the laser light emitted from the laser light source 403 is irradiated onto the surfaces of the charged electrophotographic photoreceptors 401a to 401d. It is possible. Accordingly, charging, exposure, development, primary transfer, and cleaning are sequentially performed in the rotation process of the electrophotographic photosensitive members 401a to 401d, and the toner images of the respective colors are transferred onto the intermediate transfer belt 409 in an overlapping manner.

  The intermediate transfer belt 409 is supported by a driving roll 406, a back roll 408, and a tension roll 407 with a predetermined tension, and can rotate without causing deflection due to the rotation of these rolls. The secondary transfer roll 413 is disposed so as to contact the back roll 408 via the intermediate transfer belt 409. The intermediate transfer belt 409 that has passed between the back roll 408 and the secondary transfer roll 413 is cleaned by, for example, a cleaning blade 416 disposed in the vicinity of the drive roll 406 and then repeatedly used for the next image forming process. Is done.

  A tray (recording medium tray) 411 is provided at a predetermined position in the housing 400, and the recording medium 500 such as paper in the tray 411 is moved between the intermediate transfer belt 409 and the secondary transfer roll 413 by the transfer roll 412. Then, the paper is sequentially transferred between two fixing rolls 414 facing each other, and then discharged to the outside of the housing 400.

In the above description, the case where the intermediate transfer belt 409 is used as the intermediate transfer member has been described. However, the intermediate transfer member may have a belt shape like the intermediate transfer belt 409 or a drum shape. There may be.
Conventionally known resins are used as the resin material used as the base material of the intermediate transfer member in the belt shape. For example, polyimide resin, polycarbonate resin (PC), polyvinylidene fluoride (PVDF), polyalkylene terephthalate (PAT), ethylenetetrafluoroethylene copolymer (ETFE) / PC, ETFE / PAT, PC / PAT blend material, polyester Resin materials such as polyether ether ketone and polyamide, and resin materials using these as main raw materials. Furthermore, you may mix | blend and use a resin material and an elastic material.

  Further, when adopting a drum-shaped configuration as the intermediate transfer member, it is desirable to use a cylindrical substrate formed of aluminum, stainless steel (SUS), copper or the like as the substrate. An elastic layer is coated on the cylindrical base material as necessary, and a surface layer is formed on the elastic layer.

[Process cartridge]
The process cartridge according to the present embodiment includes an image carrier and a charging member such as the above-described charging roll that contacts the surface of the image carrier and charges the surface of the image carrier.
Further, the process cartridge according to the present embodiment is a means other than the above-described means, for example, a latent image forming means for forming a latent image on the surface of the charged image carrier, and a latent image formed on the surface of the image carrier. Developing means for forming a toner image by developing with toner, transfer means for transferring the developed toner image to the recording medium, fixing means for fixing the toner image transferred to the surface of the recording medium, remaining on the surface of the image carrier It may include at least one means such as a cleaning means for removing the toner.

  FIG. 8 is a diagram schematically showing an example of a process cartridge according to the present embodiment. The process cartridge 300 includes, together with the electrophotographic photosensitive member 207, a charging device 208, a developing device 211, a cleaning device (cleaning means) 213, an opening 218 for exposure, and an opening (not shown) for static elimination exposure. Are combined and integrated with a housing 219 having mounting rails 216.

  The process cartridge 300 is detachable from an image forming apparatus main body including other components (not shown) such as a transfer device 212 and a fixing device, and constitutes an image forming apparatus together with the image forming apparatus main body.

  Hereinafter, the present invention will be specifically described with reference to conductive charging rolls as examples, but the present invention is not limited to these examples.

<Example 1>
[Preparation of charging roll]
-Formation of adhesive layer-
After electroless nickel plating having a thickness of 5 μm, a conductive support made of SUM23L having a diameter of 8 mm and subjected to hexavalent chromic acid was prepared. A conductive support in which a mixture (composition for forming an adhesive layer) containing the following adhesive and conductive agent is mixed with a ball mill for 12 hours, and then an adhesive layer is formed on the surface of the conductive support with a thickness of 20 μm by brushing. A was obtained.

(Adhesive layer forming composition)
-Adhesive 100 parts by mass (polyolefin adhesive XJ-150: manufactured by Road Far East)
・ Conductive agent 2 parts by mass (Carbon Black Ketjen Black EC: Ketjen Black International)

-Formation of elastic layer-
A mixture (composition for forming an elastic layer) having the following composition was kneaded with a 55 L kneader, an elastic layer was formed on the surface of the conductive support A on which the adhesive layer was formed, using an injection molding machine, and vulcanized. Thereafter, an elastic roll A having a diameter of 12 mm was obtained by polishing.
The temperature at the time of kneading was defined as the temperature before crosslinking, and the temperature of the mold of the injection molding machine was defined as the temperature at crosslinking. In addition, the temperature at the time of kneading | mixing measured the temperature of depth 10cm by inserting a temperature probe into rubber | gum after completion | finish of kneading | mixing.

(Composition for elastic layer formation)
Rubber component 100 parts by mass (epichlorohydrin-ethylene oxide-allyl glycidyl ether copolymer rubber Hydrin T3106: manufactured by Nippon Zeon)
-Conductive agent (carbon black Asahi Thermal: manufactured by Asahi Carbon) 10 parts by mass-Conductive agent (Ketjen Black EC: manufactured by Lion) 2 parts by mass-Ionic conductive agent (lithium perchlorate) 1 part by mass-Vulcanizing agent 1.5 parts by mass (organic sulfur: 4,4′-dithiodimorpholine Balnock R: manufactured by Ouchi Shinsei Chemical Co., Ltd.)
-Vulcanization accelerator A 1.5 parts by mass (thiazole di-2-benzothiazolyl disulfide Noxeller DM-P: manufactured by Ouchi Shinsei Chemical Co., Ltd.)
・ 1.8 parts by mass of vulcanization accelerator B (thiuram-based tetraethylthiuram disulfide noxeller TET-G: manufactured by Ouchi Shinsei Chemical Co., Ltd.)
・ Vulcanization accelerator (1 type of zinc oxide: manufactured by Shodo Chemical Co., Ltd.) 3 parts by mass ・ Stearic acid 1.0 part by mass

-Formation of surface layer-
Dispersion A obtained by dispersing the following mixture (surface layer forming composition) with a bead mill was diluted with methyl ethyl ketone (MEK), dip-coated on the surface of the elastic roll A, and then at 180 ° C. for 30 minutes. Heat drying was performed to form a surface layer having a thickness of 7 μm, and a charging roll 1 was obtained.

(Surface layer forming composition)
・ 100 parts by mass of polymer material (saturated copolymer polyester resin solution Byron 30SS: manufactured by Toyobo Co., Ltd.)
-Curing agent 26.3 parts by mass (amino resin solution Super Becamine G-821-60: manufactured by DIC Corporation)
-Conductive agent 10 parts by mass (carbon black MONARCH1000: manufactured by Cabot Corporation)

[Evaluation]
In addition to measuring the reaction start temperature, pre-vulcanization temperature, and vulcanization temperature of the rubber component contained in the rubber composition used to form the elastic layer, the vulcanizing agent and the vulcanization accelerator, the elastic layer was formed. The Mooney viscosity increase, bleed / bloom, and the image quality when the produced charging roll was attached to the image forming apparatus to form an image were evaluated, and the results are shown in Table 1.

<Measurement of reaction start temperature of vulcanized compound>
Specifically, the reaction start temperature of each vulcanized compound was measured by the following method.
Epichlorohydrin - ethylene oxide - allyl glycidyl ether copolymer rubber to a mixture of each with one sole (unvulcanized) and vulcanization system formulation, 10x tc90 in vulcanization characteristics of the rubber composition at different temperatures Measurement was performed until time, and the temperature when the torque began to rise continuously during that time was defined as the reaction start temperature of the vulcanized compound. Even if the measurement temperature is raised and the temperature at which the rubber composition is normally vulcanized, if the reaction does not start, the amount of the vulcanized compound is insufficient, so increase the amount appropriately and measure. . Since the reaction start temperature is not easily dependent on the blending amount, no change is seen in the reaction start temperature even when the amount is increased. The measurement was performed using CURELASTOMETER V (manufactured by JSR).

<Mooney viscosity increase evaluation>
The increase in Mooney viscosity was evaluated by the following method.
The Mooney viscosity was measured after kneading and cooling and 3 days later, and the difference was taken as the Mooney viscosity increase. Mooney viscosity was measured under the following conditions in accordance with JIS K6300-1.
Type of rotor: L type Test temperature: 100 ° C
Preheating time: 1 minute Test time: 4 minutes Measurement was performed using ROTORLESS MOONEY RLM-3 (manufactured by Toyo Seiki Seisakusho Co., Ltd.).
As the Mooney viscosity increase is larger, the vulcanization reaction starts before the vulcanization step and the vulcanization proceeds.

<Bleed / Broom evaluation>
The elastic roll A was stored for 30 days under high temperature and high humidity (45 ° C., 95% RH), and the presence or absence of bleeding or blooming on the surface of the rubber roll was confirmed.
◎: No change ○: Minor bleed or bloom (level that is practically acceptable)
Δ: Partially bleed or bloom (practically problematic level)
×: Bleed or bloom on the entire surface

<Image quality evaluation>
-Image quality evaluation at high temperature and high humidity / low temperature and low humidity-
The charging roll 1 is mounted on a color copier DocuCentre-IV C5570: Fuji Xerox drum cartridge, in a low temperature and low humidity (10 ° C, 15% RH) environment and in a high temperature and high humidity (28 ° C, 85% RH) environment. The image quality was evaluated by 50%, 30%, and 0% halftone printing. The results are shown in Table 1.
A: Density unevenness, white spots, and color spots are not generated.
○: Minor density unevenness, white spots, color spots, and density increases due to lowering of the photoreceptor surface potential partially occur.
Δ: Minor density unevenness, white point, color point, density increase due to decrease in photoreceptor surface potential.
X: Density increase, white point, color point, density increase due to decrease in photoreceptor surface potential occurs.

-Image quality evaluation after storage at high temperature and high humidity-
The drum cartridge equipped with the charging roll 1 was stored in a high temperature and high humidity (45 ° C., 95% RH) environment for 30 days, and then the surface state was observed and the image quality was evaluated under the same conditions as described above.
A: There is no change in the surface state of the charging roll and the surface of the photoreceptor, and there is no problem in image quality.
○: There is a change in the surface state of the charging roll or the surface of the photoreceptor, but there is no problem in image quality.
Δ: There is a change to the surface state of the charging roll or the surface of the photosensitive member, and a slight defect in image quality is generated (a level at which there is no problem with output of about 10 sheets). Or minor axial streaks that may be caused by compression set or bleeding out.
X: There is a change to the surface state of the charging roll or the surface of the photosensitive member, and defects in image quality occur. Alternatively, axial streaks that may be caused by compression set or bleed-out are generated.

<Example 2>
[Preparation of charging roll]
-Formation of adhesive layer-
As in Example 1, a conductive support B having an adhesive layer formed around the conductive support was obtained.

-Formation of elastic layer-
An elastic layer B was obtained by forming an elastic layer in the same manner as in Example 1 except that the vulcanization accelerator B was changed as follows.
-Vulcanization accelerator B 1.3 parts by mass (thiuram-based tetramethylthiuram disulfide Noxeller TT-P: manufactured by Ouchi Shinsei Chemical Co., Ltd.)

-Formation of surface layer-
A surface layer was formed in the same manner as in Example 1 to obtain a charging roll 2.

[Evaluation]
Table 1 shows the results of various evaluations conducted in the same manner as in Example 1.

<Example 3>
[Preparation of charging roll]
-Formation of adhesive layer-
As in Example 1, a conductive support C in which an adhesive layer was formed around the conductive support was obtained.

-Formation of elastic layer-
Vulcanization accelerator B was changed as described below, vulcanization accelerator C was further added, kneading was performed while cooling with an open roll, and the temperature before vulcanization was set to 70 ° C. Other than this, an elastic layer was formed in the same manner as in Example 1, and an elastic roll C was obtained.

・ Vulcanization accelerator B 1.0 parts by mass (thiuram-based tetraethylthiuram disulfide Noxeller TET-G: manufactured by Ouchi Shinsei Chemical Co., Ltd.)
-Vulcanization accelerator C 0.4 parts by mass (thiuram dipentamethylene thiuram tetrasulfide noxeller TRA: manufactured by Ouchi Shinsei Chemical Co., Ltd.)

-Formation of surface layer-
A surface layer was formed in the same manner as in Example 1 to obtain a charging roll 3.

[Evaluation]
Table 1 shows the results of various evaluations conducted in the same manner as in Example 1.

<Comparative Example 1>
[Preparation of charging roll]
-Formation of adhesive layer-
The electroconductive support body a which formed the contact bonding layer similarly to Example 1 was obtained.

-Formation of elastic layer-
An elastic layer a was obtained by forming an elastic layer in the same manner as in Example 3 except that kneading was performed in the same manner as in Example 1.

-Formation of surface layer-
A surface layer was formed in the same manner as in Example 1 to obtain a charging roll 11.

[Evaluation]
Table 2 shows the results of various evaluations conducted in the same manner as in Example 1.

<Comparative example 2>
[Preparation of charging roll]
-Formation of adhesive layer-
The electroconductive support body b in which the contact bonding layer was formed similarly to Example 1 was obtained.

-Formation of elastic layer-
An elastic layer b was obtained by forming an elastic layer in the same manner as in Example 1 except that the vulcanization accelerator was changed as follows.

・ Vulcanization accelerator A 2.0 parts by mass (thiazole di-2-benzothiazolyl disulfide Noxeller DM-P: manufactured by Ouchi Shinsei Chemical Co., Ltd.)
・ Vulcanization accelerator B 1.0 part by mass (thiuram dipentamethylene thiuram tetrasulfide noxeller TRA: manufactured by Ouchi Shinsei Chemical Co., Ltd.)

-Formation of surface layer-
A surface layer was formed in the same manner as in Example 1 to obtain a charging roll 12.

[Evaluation]
Table 2 shows the results of various evaluations conducted in the same manner as in Example 1.

<Comparative Example 3>
[Preparation of charging roll]
-Formation of adhesive layer-
The electroconductive support body c in which the contact bonding layer was formed similarly to Example 1 was obtained.

-Formation of elastic layer-
An elastic layer c was obtained by forming an elastic layer in the same manner as in Example 1 except that the vulcanizing agent was changed as follows.
・ Vulcanizing agent (sulfur 200 mesh: manufactured by Tsurumi Chemical Co., Ltd.) 3.0 parts by mass

-Formation of surface layer-
A surface layer was formed in the same manner as in Example 1 to obtain a charging roll 13.

[Evaluation]
Table 2 shows the results of various evaluations conducted in the same manner as in Example 1.

<Comparative example 4>
-Formation of adhesive layer-
The electroconductive support body d in which the contact bonding layer was formed similarly to Example 1 was obtained.

-Formation of elastic layer-
An elastic layer d was obtained by forming an elastic layer in the same manner as in Example 1 except that the kneader cooling temperature at the time of kneading was raised and the rubber at the time of kneading was changed to 130 ° C.

-Formation of surface layer-
A surface layer was formed in the same manner as in Example 1 to obtain a charging roll 14.

[Evaluation]
Table 3 shows the results of various evaluations conducted in the same manner as in Example 1.

<Comparative Example 5>
-Formation of adhesive layer-
The electroconductive support body e which formed the contact bonding layer similarly to Example 1 was obtained.

-Formation of elastic layer-
An elastic layer e was obtained by forming an elastic layer in the same manner as in Example 1 except that the molding temperature was changed to 160 ° C.

-Formation of surface layer-
A surface layer was formed in the same manner as in Example 1 to obtain a charging roll 15.

[Evaluation]
Table 3 shows the results of various evaluations conducted in the same manner as in Example 1.

<Example 4>
-Formation of adhesive layer-
As in Example 1, a conductive support D in which an adhesive layer was formed around the conductive support was obtained.

-Formation of elastic layer-
An elastic layer D was obtained by forming an elastic layer in the same manner as in Example 1 except that the vulcanization accelerator B was not added.

-Formation of surface layer-
A surface layer was formed in the same manner as in Example 1 to obtain a charging roll 4.

[Evaluation]
Table 3 shows the results of various evaluations conducted in the same manner as in Example 1.

30, 30A, 30B ... charging roll (an example of a charging member), 31 ... conductive support, 32 ... adhesive layer, 33 ... elastic layer, 34 ... intermediate layer, 35 ... surface layer, 40 ... cleaning roll, 100 ... charging 200, 210, 220 ... image forming device, 207 ... electrophotographic photosensitive member (image holding member), 208 ... charging device, 209 ... power source, 210 ... exposure device, 211 ... developing device, 212 ... transfer device, 213 ... Cleaning device, 214 ... neutralizer, 215 ... fixing device, 216 ... mounting rail, 218 ... opening for exposure, 219 ... housing, 300 ... process cartridge, 400 ... housing, 401a to 401d ... electrophotographic photosensitive member, 402a ˜402d, charging roll, 403, laser light source (exposure device), 404a to 404d, developing device, 405a to 405d,. ,..., Drive roll, 407. Tension roll, 408. Back roll, 409 intermediate transfer belt, 410 a to 410 d, primary transfer roll, 411 tray (recording medium feeding means), 412 transfer roll, 413 ... secondary transfer roll, 414 ... fixing roll, 415a to 415d ... cleaning blade, 416 ... cleaning blade, 500 ... recording medium

Claims (3)

On a conductive support, epichlorohydrin - ethylene oxide - rubber composition comprising allyl glycidyl ether copolymer rubber, and a vulcanizing system formulation comprising at least one organic vulcanizing agent and at least one vulcanization accelerator things, said epichlorohydrin - ethylene oxide - respective reaction starting temperature determined from vulcanization curve of each one of allyl glycidyl ether copolymer rubber and the vulcanizing system formulation, prior to vulcanization of the rubber composition The vulcanization temperature of the rubber composition and the vulcanization temperature when the rubber composition is vulcanized satisfy the following formula (1), and one melting point of each of the vulcanized compounds has the following formula (2 ) To form an elastic layer by vulcanization under conditions satisfying
The manufacturing method of the charging member which has this.
Formula (1): Pre-vulcanization temperature <reaction initiation temperature <temperature at vulcanization Formula (2): Melting point of vulcanized compound <temperature at vulcanization   The method for manufacturing a charging member according to claim 1, wherein the organic vulcanizing agent is an organic sulfur vulcanizing agent. The rubber composition before Symbol organic vulcanizing agent include 4,4'-dithiodimorpholine, claim 1 or claim containing thiazole-based vulcanization accelerator and the thiuram based vulcanization accelerator as the vulcanization accelerator Item 3. A method for producing a charging member according to Item 2.

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