JP5814660B2 - Charging member and manufacturing method thereof - Google Patents

Description

The present invention relates to a charging member used in an electrophotographic apparatus and a manufacturing method thereof.

  A conductive member typified by a conductive roller used in an electrophotographic apparatus generally has a conductive shaft core and a conductive layer provided on the outer periphery thereof. The conductive layer usually contains a binder resin and a conductive agent dispersed in the binder resin. Here, electronic conductive agents such as conductive metal oxide particles are known as conductive agents that can lower the electrical resistance of the conductive layer relatively easily. However, the electrical resistance of a conductive layer made conductive with an electronic conductive agent may vary greatly depending on the dispersion state of the electronic conductive agent in the conductive layer. In order to suppress the variation in electric resistance of the conductive layer and obtain a conductive member having stable quality, an electronic conductive agent having good dispersibility with respect to the binder resin constituting the conductive layer has been demanded.

  Patent Document 1 discloses a conductive inorganic material in which a sulfonic acid group having ionic conductivity is introduced into the surface of an inorganic powder by silane coupling treatment as an inorganic powder having low resistance and excellent uniform dispersibility in a resin. A powder is disclosed.

JP-A-10-007932

  The present inventors examined a conductive member provided with a conductive layer made conductive using the conductive inorganic powder according to Patent Document 1. As a result, the inorganic powder was excellent in dispersibility in the binder resin, and an effect of stabilizing the electric resistance of the conductive layer was recognized. However, with the diversification of the usage environment of electrophotographic apparatuses in recent years, the present inventors have recognized that it is necessary to further reduce the environmental dependency of electrical resistance for charging members. .

  Specifically, although it exhibits an appropriate electrical resistance value in a normal temperature and normal humidity (for example, temperature 25 ° C., relative humidity 50%) environment, in a low temperature and low humidity (for example, temperature 15 ° C., relative humidity 10%) environment, The electrical resistance value often increases.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a charging member in which the electrical resistance value is less dependent on the environment and can stably form a high-quality electrophotographic image even in various environments. Another object of the present invention is to provide an electrophotographic apparatus capable of stably forming a high-quality electronic image even under various environments.

The present invention relates to a charging member having a conductive shaft body and a conductive layer, the conductive layer including a binder resin and conductive particles, and the conductive particles are formed on the surface of the ion exchange group. And the molecular chain unit represented by the formula (1), and the ion exchange group and the molecular chain unit represented by the formula (1) are in contact with the reactive functional group on the surface of the particle serving as the base of the conductive particle. A charging member formed on the surface of the conductive particles by reaction .

  In formula (1), n is an integer of 1 or more.

Moreover, this invention is a manufacturing method of the charging member which has the electroconductive axial core body and conductive layer containing the following processes.
[1] A compound (A) having an ion exchange group, a compound (B) having a molecular chain unit represented by the formula (1), and particles (C) reactive with the above (A) and (B) Preparing a mixture of the materials to be included and forming a layer of the mixture on the outer periphery of the shaft core; and [2] forming the conductive layer by reacting and curing the mixture.

Furthermore, this invention is a manufacturing method of the charging member which has the electroconductive axial core body containing the following processes, and a conductive layer.
[1] A compound (A) having an ion exchange group, a compound (B) having a molecular chain unit represented by the formula (1), and particles (C) reactive with the above (A) and (B) Step of preparing conductive particles by mixing and reacting the materials to be included, and then [2] preparing a mixture of materials including the conductive particles and a binder resin, and forming a layer of the mixture on the outer periphery of the shaft core body And [3] curing the mixture to form a conductive layer.

  According to the present invention, it is possible to obtain a charging member that is less dependent on the environment of the electrical resistance value and can stably form a high-quality electrophotographic image even in various environments. In addition, according to the present invention, an electrophotographic apparatus capable of stably forming high-quality electrophotographic images under various environments can be obtained.

The schematic block diagram of the charging roller of this invention is shown. The schematic block diagram of the charging roller of this invention is shown. 1 is a schematic view of an electrophotographic apparatus using a charging roller of the present invention. 1 is a schematic view of a process cartridge using a charging roller of the present invention. The schematic block diagram of the charging roller of this invention is shown.

  The reason why the charging member of the present invention exhibits the above effect is that the counter ion of the ion exchange group can be stably dissociated by having the molecular chain unit represented by the formula (1) in the vicinity of the ion exchange group. It is estimated. The ion exchange group and the counter ion are bonded by an ionic bond. The oxygen atom of the unit represented by the formula (1) can donate electrons to these ion exchange groups or counter ions. Thereby, the ion binding force between the ion exchange group and the counter ion is lowered, and the counter ion is easily dissociated.

<Charging member>
The present invention will be described in detail below with a charging roller that is a roller-shaped charging member. FIG. 1 shows a schematic configuration diagram of the charging roller of the present invention. 101 is a conductive shaft core, and 102 is a conductive layer. In addition, as shown in FIG. 2, the conductive layer may be a multilayer such as 202 and 203. Furthermore, as shown in FIG. 5, a surface layer 504 that adds a function as a charging roller may be provided on the conductive layers 502 and 503.

[Conductive shaft core]
The conductive shaft core body has conductivity in order to supply power to the surface of the charging roller through the shaft core body.

[Conductive layer]
The conductive layer contains a binder resin and conductive particles. When there are a plurality of conductive layers as shown in FIGS. 2 and 5, at least one of the layers only needs to include a binder resin and conductive particles. Moreover, all the layers may contain binder resin and electroconductive particle.

  Examples of the structure of the conductive layer include the following two forms. As the “first form”, particles (C) serving as a base of conductive particles, a compound (A) having an ion exchange group, and a compound (B) having a molecular chain unit represented by the formula (1) Are mixed, the particles are reacted with both compounds, and a conductive layer is formed by the reaction product. In the first embodiment, the compound having a molecular chain unit represented by the formula (1) also serves as a binder resin. Moreover, you may add the 3rd component which can react with the said component other than the said component as needed. In the first embodiment, it is possible to minimize the components unnecessary for the expression of conductivity, and there is an advantage that the degree of freedom in design such as the mixing ratio of the compound (A) and the compound (B) is high. In the “second form”, conductive particles in which ion exchange groups and molecular chain units represented by the formula (1) are bonded to the surface of the base particle in advance are prepared, and the conductive particles are combined with a binder resin. In this mode, a conductive layer is formed by mixing.

  In formula (1), n is an integer of 1 or more.

(Conductive particles)
The conductive particle is a particle having an ion exchange group and a molecular chain unit represented by the formula (1) on the surface thereof. Such conductive particles react, for example, a compound (A) having an ion exchange group and a compound (B) having a molecular chain unit represented by the formula (1) with the compounds (A) and (B). It can be prepared by reacting with particles (C) having properties. In addition to the above components, a third component capable of reacting with the above components may be added as necessary.

(Particle (C))
The particle (C) is a particle that becomes a base of conductive particles. The base particles are stable without melting and dissolving in the binder resin of the conductive layer, the compound (A) having an ion exchange group, and the compound (B) having a molecular chain unit represented by the formula (1). Is required. Any material may be used regardless of whether it is an inorganic compound or an organic compound as long as the above characteristics can be satisfied.

  Examples of inorganic compounds include metal oxides such as silica, titanium oxide, aluminum oxide, and zinc oxide. Examples of the organic compound include resin particles. Specifically, resin particles such as an acrylic resin, a urethane resin, a styrene resin, a fluorine resin, and a phenol resin can be used.

The particle size of the base material is preferably 0.05 μm or more and 30 μm or less in order to ensure necessary dispersibility. Moreover, it is preferable that a specific surface area is large so that many compounds (A) and a compound (B) can react on the particle | grain surface. The specific surface area is preferably 50 m ² / g or more. When it is 50 m ² / g or more, a large number of the compounds (A) and the compounds (B) can be bonded, and the range for adjusting the bonding ratio of the compounds (A) and the compounds (B) is widened. Can be used in various environments.

  The reactive functional group on the surface of the particles serving as a base reacts with the compound (A) and the compound (B) to be bonded. However, when the surface of the particle does not have a sufficient number of reaction parts due to the material of the base particle, the particle surface may be poor in reactivity. In such a case, in order to advance the reaction efficiently, the base particle may be subjected to a surface treatment to replace the reactive site with a highly reactive functional group, or to increase the highly reactive functional group. preferable. A known method can be used as a method for surface treatment of the base particles, but a coupling agent capable of introducing various functional groups from the viewpoint of reactivity with the compound (A) and the compound (B). Treatment is preferred.

  The coupling agent is selected so that it can efficiently react with the terminal reaction part of the compound (A) and the compound (B). For example, when the reaction part of a compound (A) and a compound (B) is an epoxy group, it processes with the coupling agent which has an amino group. Generally, it is preferable to treat with a coupling agent having an amino group, an epoxy group, a mercapto group, or an isocyanate group because it can efficiently react with various reaction units. Although various coupling agents can be used as the coupling agent, a silane coupling agent is preferably used. Specifically, the following are mentioned as a coupling agent which has an amino group. N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane. Examples of the coupling agent having an epoxy group include the following. 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycid Xylpropyltriethoxysilane. Examples of the coupling agent having a mercapto group include 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane. Examples of the coupling agent having an isocyanate group include 3-isocyanatopropyltriethoxysilane.

(Compound (A))
The compound (A) having an ion exchange group has a reactive functional group at the terminal opposite to the terminal which is an ion exchange group. Examples of ion exchange groups include sulfonic acid groups, phosphonic acid groups, carboxyl groups, and quaternary ammonium bases. It is more preferable that the ion exchange group is a quaternary ammonium base or a sulfonic acid group because the electric resistance value of the conductive layer can be set to a desired value even when the amount of conductive particles added is small.

  The reactive functional group of the compound (A) makes it easy to react with the parent particle (C). It is preferable to use a material that easily reacts with a functional group on the particle surface as a base and bonds firmly. For example, an epoxy group, an amino group, a mercapto group, an isocyanate group, a hydroxyl group, chlorine, etc. are mentioned. Compound (A) is preferably added in an amount of 0.2 parts by mass or more and 15 parts by mass or less with respect to 100 parts by mass in total of the binder resin and conductive particles forming the conductive layer. Necessary electrical conductivity can be expressed within this range. Examples of the compound having such an ion exchange group include glycidyltrimethylammonium, chloromethylsulfonic acid, 4-aminomethylbenzenesulfonic acid, chloromethylphosphonic acid, aminomethylphosphonic acid, choline chloride and the like.

(Compound (B))
The compound (B) having the molecular chain unit represented by the formula (1) may be any compound as long as it has this unit and has a reactive functional group at the terminal. In the case where the structure of the conductive layer is the first form, it can also serve as an effect as a binder resin. Examples of the compound (B) include compounds having units derived from polyethylene glycol in the molecular chain. N in the formula (1) may be 1 or more, but is preferably 9 or less. When n is 9 or less, the crystallinity does not become too strong, so that conductivity is easily developed. The proportion of the unit of formula (1) in the conductive layer is preferably 5% by mass or more and 80% by mass or less. Within this range, the conductivity can be appropriately controlled without the crystallinity becoming too high. More preferably, it is 20 mass% or more and 60 mass% or less.

  As the reactive functional group in the compound (B), it is preferable to use a reactive functional group that easily reacts with the functional group on the surface of the base particle to bond strongly. Moreover, it is preferable to have a highly reactive functional group at both ends of the molecular chain unit represented by the formula (1). Thereby, it becomes possible to couple | bond with the particle | grains (C) used as a base | substrate in the both ends of a compound (A), and can raise the intensity | strength of a conductive layer. Preferred functional groups include, for example, epoxy groups, amino groups, mercapto groups, isocyanate groups, hydroxyl groups, chlorine and the like.

  Taking the above structure into consideration, particularly preferred compounds (B) include polyethylene glycol diglycidyl ether having an epoxy group at both ends, 2,2- (ethylenedioxy) bisethylamine having an amino group at both ends, Examples include polyethylene glycol having hydroxyl groups at both ends.

(binder)
In the case where the structure of the conductive layer is the second form, the binder may be any of rubber, elastomer, resin and the like. Specific examples of the rubber include the following. Ethylene-propylene-diene copolymer (EPDM), polybutadiene, natural rubber, polyisoprene, styrene-butadiene rubber (SBR), chloroprene (CR), acrylonitrile-butadiene rubber (NBR), silicone rubber, urethane rubber, epichlorohydride Rubber. Specific examples of the elastomer include the following. Butadiene resin (RB); polystyrene-based polymer materials such as polystyrene, styrene-butadiene-styrene elastomer (SBS), styrene-vinyl acetate copolymer; polyolefin-based polymer materials such as polyethylene (PE) and polypropylene (PP); Polyester polymer materials; Polyurethane polymer materials; Acrylic polymer materials such as acrylic resins and butadiene-acrylonitrile copolymers; Thermoplastic elastomers such as PVC and RVC. Moreover, the mixture which combined these 1 type (s) or 2 or more types may be sufficient. As the resin, a resin such as a thermosetting resin or a thermoplastic resin is used. Specifically, urethane resin, fluorine resin, silicone resin, acrylic resin, polyamide resin, and the like can be given.

[Surface layer]
The charging roller can be provided with a surface layer as required. The surface layer is provided for the purpose of preventing dirt, for example, in order to satisfy the functionality required for the charging roller. As the material for the surface layer, known materials can be used, and examples thereof include a binder, a conductive agent, a roughening agent, and insulating inorganic fine particles.

  As the binder, a resin such as a thermosetting resin or a thermoplastic resin is used. Specifically, urethane resin, fluorine resin, silicone resin, acrylic resin, polyamide resin, and the like can be given. As the conductive agent, conductive particles such as carbon black, graphite, conductive titanium oxide, and conductive metal oxide of conductive tin oxide, or the conductive particles may be used as long as the effects of the present invention are not impaired. Conductive particles combined with particles can be used. Moreover, the resin particle which comprises the electrically conductive layer of this invention can also be used. A desired electrical resistance value can be obtained by appropriately dispersing these conductive particles in the surface layer.

  The roughening agent can form minute irregularities on the surface of the charging member, and can improve the charging uniformity. Fine irregularities on the surface are particularly effective for the DC charging method. As the roughening material, it is preferable to use fine particles made of a polymer compound such as urethane fine particles, silicone fine particles, and acrylic fine particles.

[Method of manufacturing charging member]
The charging member of the present invention can be produced, for example, by the following “Method 1” and “Method 2”.

  Method 1 is a method including the following steps. [1] A compound (A) having an ion exchange group, a compound (B) having a molecular chain unit represented by the formula (1), and particles (C) reactive with the above (A) and (B) Preparing a mixture of the materials to be included and forming a layer of the mixture on the outer periphery of the shaft core; and [2] forming the conductive layer by reacting and curing the mixture.

  Method 2 is a method including the following steps. [1] A compound (A) having an ion exchange group, a compound (B) having a molecular chain unit represented by the formula (1), and particles (C) reactive with the above (A) and (B) Step of preparing conductive particles by mixing and reacting the materials to be included, and then [2] preparing a mixture of materials including the conductive particles and a binder resin, and forming a layer of the mixture on the outer periphery of the shaft core body And [3] curing the mixture to form a conductive layer.

  According to Method 1, the base particles (C), the compound (A) having an ion exchange group, and the compound (B) having a unit represented by the formula (1) are more uniformly dispersed in the conductive layer. it can.

  In Method 1 and Method 2, an adhesive may be applied in advance to the outer periphery of the shaft core body to improve the adhesion with the conductive layer or the like. For mixing the materials, a known dispersion apparatus using beads such as a sand mill, a paint shaker, a dyno mill, and a pearl mill can be suitably used. Examples of a method for forming a mixture layer on the outer periphery of the shaft core include a method in which the mixture is applied as a coating solution by a known method such as a dipping method, a spray method, or a roll coating method.

<Electrophotographic device>
FIG. 3 is a schematic view of an electrophotographic apparatus using the charging roller of the present invention. A charging roller 302 for charging the electrophotographic photosensitive member 301, a latent image forming device 308 for performing exposure, a developing device 303 for developing the toner image, a transfer device 305 for transferring to the transfer material 304, and a transfer toner on the electrophotographic photosensitive member are collected. A cleaning device 307 for fixing the toner image, a fixing device 306 for fixing the toner image, and the like. The electrophotographic photoreceptor 301 is a rotary drum type having a photosensitive layer on a conductive substrate. The electrophotographic photosensitive member 301 is rotationally driven in the direction of the arrow at a predetermined peripheral speed (process speed).

  The charging roller 302 is placed in contact with the electrophotographic photosensitive member 301 by being pressed with a predetermined force. The charging roller 302 is driven to rotate in accordance with the rotation of the electrophotographic photosensitive member 301, and applies a predetermined DC voltage from the charging power source 313 to charge the electrophotographic photosensitive member 301 to a predetermined potential.

  As the latent image forming apparatus 308 that forms a latent image on the electrophotographic photosensitive member 301, for example, an exposure apparatus such as a laser beam scanner is used. An electrostatic latent image is formed by performing exposure corresponding to image information on the uniformly charged electrophotographic photosensitive member 301. The developing device 303 has a contact type developing roller disposed in contact with the electrophotographic photosensitive member 301. The toner electrostatically processed to the same polarity as the charged polarity of the photosensitive member is reversely developed to visualize and develop the electrostatic latent image into a toner image.

  The transfer device 305 has a contact-type transfer roller. The toner image is transferred from the electrophotographic photosensitive member 301 to a transfer material 304 such as plain paper. The transfer material 304 is transported by a paper feed system having a transport member. The cleaning device 307 includes a blade-type cleaning member and a collection container. After the transfer, the transfer residual toner remaining on the electrophotographic photosensitive member 301 is mechanically scraped and collected. Here, it is also possible to remove the cleaning device 307 by adopting a simultaneous development cleaning system in which the developing device 303 collects the transfer residual toner. The fixing device 306 is configured by a heated roll or the like, fixes the transferred toner image on the transfer material 304, and discharges the toner image outside the apparatus.

<Process cartridge>
As shown in FIG. 4, it is also possible to use a process cartridge in which an electrophotographic photosensitive member 301, a charging roller 302, a developing device 303, a cleaning device 307, and the like are integrated and designed to be detachable from the image forming apparatus.

  Hereinafter, the present invention will be described specifically by way of examples. In addition, the evaluation method of the charging roller in the embodiment is as follows.

[1. (Measurement of electrical resistance)
In N / N environment (temperature 23 ° C., humidity 50% RH) or L / L environment (temperature 15 ° C., humidity 10% RH), the charging roller is brought into contact with the metal drum (load at both ends of 4.9 N on one side) A voltage of DC 200V was applied between the cored bar and the metal drum, and the current value was measured. Thereby, the electric resistance value of the charging roller was calculated.

[2. (Image evaluation)
The charging roller obtained in the example or the comparative example was attached to the apparatus shown below, and image evaluation was performed. As an electrophotographic laser printer, an LBP5400 manufactured by Canon Inc. modified for high speed was used, the output speed of the recording medium was 250 mm / sec, and the image resolution was 600 dpi. All image evaluations were performed in an L / L environment (temperature 15 ° C., humidity 10% RH), and a halftone image (an image that draws a horizontal line with a width of 1 dot and an interval of 2 dots in the direction perpendicular to the rotation direction of the photoconductor). Output was done. Evaluation was made according to the following criteria.
A: No horizontal stripe image.
B: A slight horizontal streak-like line can be seen in part.
C: A slight horizontal streak-like line can be seen on the entire surface.
D: Severe horizontal streak-like line is seen and is conspicuous.

<Manufacture example A1-A8> Manufacture of particle | grains 1-particle 8 used as a base body These manufacture examples are the manufacture example of particle | grains 1-particle 8 used as a base | substrate used in order to form the electroconductive layer of a 1st form. It is.

  Particles (raw materials) and a silane coupling agent shown in Table 1 were prepared, and each particle was treated with a silane coupling agent according to the following procedure. A silane coupling agent solution having a concentration of 40% by mass was prepared in advance using isopropyl alcohol (IPA) / water = 95/5 (mass ratio) as a solvent. First, the particles were put into a Henschel mixer. Subsequently, the silane coupling agent solution was dropped while rotating the mixer. After confirming that the silane coupling agent solution was uniformly coated on the surface of the particles, the particles were taken out of the mixer and dried at 80 ° C. for 1 hour. Thus, particles 1 to 8 serving as a base were obtained.

Examples 1 to 38 and Comparative Examples 1 and 2
A charging roller was prepared and evaluated by the following method.

(1. Preparation of rubber composition)
The types and amounts of materials shown in Table 2 below were mixed with an open roll to prepare an unvulcanized rubber composition.

(2. Creation of conductive elastic roller)
A cylindrical rod having a total length of 252 mm and an outer diameter of 6 mm prepared by electroless nickel plating on the surface of free-cutting steel was prepared as a conductive shaft core (core metal). A conductive adhesive was applied to a portion excluding both ends 11 mm of the conductive shaft core using a roll coater. As the adhesive, a conductive hot melt type was used.

  Next, a crosshead extruder having a core bar supply mechanism and an elastic roller discharge mechanism is prepared. A die having an inner diameter of 9.0 mm is attached to the crosshead, and the extruder and the crosshead are set to 80 ° C. The conveyance speed was adjusted to 60 mm / sec. Under these conditions, an unvulcanized rubber composition was supplied from an extruder to obtain a metal core whose surface was coated with the unvulcanized rubber composition. Next, the core metal coated with the unvulcanized rubber composition was put into a hot air vulcanization furnace at 170 ° C. and heated for 60 minutes. Thereafter, the end portion of the conductive layer was cut and removed so that the length of the elastic layer was 228 mm. Finally, the surface of the elastic layer was polished with a rotating grindstone. As a result, a conductive elastic roller having a diameter of 8.4 mm and a center diameter of 8.5 mm at positions of 90 mm from the central portion to both end sides was obtained.

(3. Formation of conductive layer)
The materials shown in Table 1 and Table 3 were mixed at the mixing ratio and amount shown in Table 4, and diluted with methyl isobutyl ketone (MIBK) so that the solid content was 27% by mass to prepare a coating solution for the conductive layer. .

  This conductive layer coating solution is dipped on a conductive elastic roller once, air-dried at room temperature for 30 minutes or more, then dried in a hot air circulating dryer set at 90 ° C. for 1 hour, and further heated to 160 ° C. It dried for 1 hour with the set hot-air circulation dryer, and formed the conductive layer on the elastic layer. The dipping coating dipping time is 9 seconds, the dipping coating lifting speed is adjusted so that the initial speed is 20 mm / s, and the final speed is 2 mm / s. Between 20 mm / s and 2 mm / s is linear with respect to time. The speed was changed. In this way, charging rollers 1 to 38 and charging rollers 101 and 102 were produced. The evaluation results are shown in Table 12.

It was confirmed by the following method that the conductive particles had an ion exchange group and a molecular chain unit represented by the formula (1) on the surface. A portion including particles of the conductive layer of the charging roller prepared in Example 1 was cut out. The cut conductive layer was subjected to ultrasonic cleaning with an excessive amount of methanol for 30 minutes. Thereafter, the washed conductive layer was taken out and dried at room temperature. The dried conductive layer was analyzed using ²⁹ Si DD / MAS NMR, ²⁹ Si CP / MAS NMR, ¹³ C DD / MAS NMR, and ¹³ C CP / MAS NMR. As a result of the above analysis, it was confirmed that the conductive particles had a quaternary ammonium base and a molecular chain unit represented by the formula (1) on the surface.

<Manufacture example B1-B17> Manufacture of electroconductive particle 1-17 These manufacture examples are the manufacture examples of electroconductive particle used in order to form the electroconductive layer of a 2nd form. The materials shown in Table 1 and Table 3 were mixed in the mixing ratios and amounts shown in Table 5 below to obtain conductive particles 1-17. The obtained conductive particles were dried and pulverized.

Similarly to Example 1, the conductive particle 1 was confirmed by the following method to have an ion exchange group and a molecular chain unit represented by the formula (1) on the surface of the conductive particle. That is, the conductive particles 1 were subjected to ultrasonic cleaning for 30 minutes using an excessive amount of methanol. Thereafter, the washed conductive particles 1 were taken out and dried at room temperature. The dried conductive particles 1 were analyzed using ²⁹ Si DD / MAS NMR, ²⁹ Si CP / MAS NMR, ¹³ C DD / MAS NMR, and ¹³ C CP / MAS NMR. As a result of the above analysis, it was confirmed that the conductive particles had a quaternary ammonium base and a molecular chain unit represented by the formula (1) on the surface.

<Manufacture example C1-C4> Manufacture of binder resin 1-4 These manufacture examples are manufacture examples of binder resin used in order to form the conductive layer of a 2nd form.

(Production Example C1: Production of Binder Resin 1)
Methyl isobutyl ketone was added to the caprolactone-modified acrylic polyol solution to adjust the solid content to 18% by mass. Binder resin 1 was manufactured by mixing the materials shown in Table 6 below including 555.6 parts by mass of this solution (solid content: 100 parts by mass). At this time, the mixture of the block HDI and the block IPDI was added so that “NCO / OH = 1.0”.

(Production Example C2: Production of Binder Resin 2)
The materials shown in Table 7 below were mixed with an open roll to produce binder resin 2.

(Production Example C3: Production of binder resin 3)
A binder resin 3 made of a two-pack type liquid silicone rubber was prepared, which was used by mixing the liquid A and liquid B having the composition shown in Table 8 below in an approximately 1: 1 ratio. Liquid A is an addition-type silicone rubber composition in which a platinum-based catalyst of material 3 is added to and mixed with a mixture of material 1 and material 2. Liquid B is an addition-type silicone rubber composition in which the cross-linking agent of material 4 and material 5 are added to the mixture of material 1 and material 2 and mixed.

(Production Example C4: Production of binder resin 4)
The materials shown in Table 9 below were mixed with an open roll to produce a binder resin 4.

[Examples 39 to 54 and Comparative Examples 3 and 4]
As shown in Table 10, conductive particles were added to the binder resin 1 and dispersed for 24 hours using a paint shaker disperser to prepare a conductive paint. The prepared paint was applied to the surface of the conductive elastic roller obtained in the same manner as in Example 1 by the same method as in Example 1 to obtain charging rollers 39 to 54 and charging rollers 103 and 104. The evaluation results are shown in Table 12.

[Examples 55-58 and Examples 65-68]
As shown in Table 10, conductive particles were added to the binder resin 2 or the binder resin 4 and mixed with an open roll. A conductive elastic roller was obtained in the same manner as in “2. Production of conductive elastic roller” in Example 1, using each of the eight types of compositions obtained. In this embodiment, the conductive elastic layer corresponds to the “conductive layer” of the present invention.

  On the other hand, methyl isobutyl ketone was added to the caprolactone-modified acrylic polyol solution to adjust the solid content to 18% by mass. A mixed solution was prepared using the materials shown in Table 11 below including 555.6 parts by mass of this solution (solid content: 100 parts by mass). At this time, the mixture of the block HDI and the block IPDI was added so that “NCO / OH = 1.0”.

  Next, 210 g of the above mixed solution and 200 g of glass beads having an average particle diameter of 0.8 mm as a medium were mixed in a 450 mL glass bottle and dispersed for 24 hours using a paint shaker disperser. After dispersion, 5.44 parts by mass of crosslinked acrylic particles “MR50G” (trade name, manufactured by Soken Chemical Co., Ltd.) as resin particles were added (an equivalent of 20 parts by weight with respect to 100 parts by weight of acrylic polyol), and then 30 more. Dispersed for a minute to obtain a coating material for forming the surface layer.

  This surface layer-forming coating material was dipped on a conductive elastic roller once, air-dried at room temperature for 30 minutes or more, then dried in a hot air circulating dryer set at 90 ° C. for 1 hour, and further set at 160 ° C. It dried for 1 hour with the hot air circulation dryer, and formed the surface layer on the conductive layer. The dipping coating dipping time is 9 seconds, the dipping coating lifting speed is adjusted so that the initial speed is 20 mm / s, and the final speed is 2 mm / s. Between 20 mm / s and 2 mm / s is linear with respect to time. The speed was changed. The charging rollers 55-58 and 65-68 were obtained by the above procedure. The evaluation results are shown in Table 12.

[Examples 59 to 64]
As shown in Table 10, conductive particles were added to the binder resin 3 to obtain six types of liquid silicone rubber compositions. As the shaft core body, a SUS cored bar made of nickel, further coated with an adhesive, and baked was used. This shaft core was placed in a mold, and each liquid silicone rubber composition was mixed in the apparatus and then injected into a cavity formed in a mold preheated to 120 ° C. Subsequently, the mold was heated at 120 ° C. to cure and cure the silicone rubber, and after cooling, the mold was removed to obtain a conductive elastic roller. Further, a surface layer was formed in the same manner as in Example 55 to obtain charging rollers 59 to 64. The evaluation results are shown in Table 12.

101: conductive shaft core 102: conductive layer 201: conductive shaft core 202: conductive layer 203: conductive layer 301: electrophotographic photosensitive member 302: charging roller 303: developing device 304: transfer material 305: transfer device 306: fixing device 307: cleaning device 308: latent image forming device 309: pre-charging exposure device 310: elastic regulating blade 311: toner supply roller 312: developing power source 313: charging power source 314: transfer power source 401: toner seal 501 : Conductive shaft core 502: Conductive layer 503: Conductive layer 504: Surface layer

Claims (5)

A charging member having a conductive shaft core and a conductive layer,
The conductive layer includes a binder resin and conductive particles, and the conductive particles have an ion exchange group and a molecular chain unit represented by the formula (1) on the surface thereof .
The ion exchange group and the molecular chain unit represented by the formula (1) are formed on the surface of the conductive particle by reaction with the reactive functional group on the surface of the particle serving as a base of the conductive particle. Charging member characterized by:

[In Formula (1), n is an integer greater than or equal to 1. ].   The charging member according to claim 1, wherein the ion exchange group is a sulfonic acid group or a quaternary ammonium base. The charging member according to claim 1 , wherein the reactive functional group is an amino group, an epoxy group, or a mercapto group. A method for producing a charging member having a conductive shaft core and a conductive layer, including the following steps:
[1] A compound (A) having an ion exchange group, a compound (B) having a molecular chain unit represented by the formula (1), and particles (C) reactive with the above (A) and (B) Preparing a mixture of materials comprising and forming a layer of the mixture on the outer periphery of the shaft core;
[2] A step of forming a conductive layer by reacting and curing the mixture.

[In Formula (1), n is an integer greater than or equal to 1. ]. A method for producing a charging member having a conductive shaft core including the following steps and a conductive layer:
[1] A compound (A) having an ion exchange group, a compound (B) having a molecular chain unit represented by the formula (1), and particles (C) reactive with the above (A) and (B) Mixing the materials comprising and reacting to prepare conductive particles, then
[2] A step of preparing a mixture of materials containing the conductive particles and a binder resin, and forming a layer of the mixture on the outer periphery of the shaft core,
[3] A step of curing the mixture to form a conductive layer.

[In Formula (1), n is an integer greater than or equal to 1. ].

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