JP2017116685A - Conductive member for electrophotographic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive member for an electrophotographic apparatus, which has a low resistance, low hardness, low sinking property and excellent chargeability compared to the prior arts and suppresses contamination.SOLUTION: The conductive member for an electrophotographic apparatus includes a conductive elastic material layer composed of: a conductive first polymer phase 1 comprising at least one polymer; a non-conductive second polymer phase 2 comprising at least one polymer and present as separated from the first polymer phase; and an interfacial phase 3 present between the first polymer phase 1 and the second polymer phase 2 and containing a compatibilizer comprising at least one of or both of a structural component of the polymer included in the first polymer phase 1 and a structural component of the polymer included in the second polymer phase 2.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a conductive member for electrophotographic equipment.

  In electrophotographic apparatuses such as copying machines, printers, and facsimiles that employ an electrophotographic system, conductive rolls such as a charging roll, a developing roll, a transfer roll, and a toner supply roll are disposed around the photosensitive drum. Further, an endless belt (conductive belt) such as an intermediate transfer belt or a paper transfer conveyance belt is provided. These conductive members include a conductive elastic body layer made of an elastic body having conductivity.

JP 2005-115204 A

  In an electronic conductive system in which an electronic conductive agent is blended, there are problems of increased hardness and deterioration due to blended conductive particles. In addition, resistance unevenness due to poor dispersion of the conductive particles to be blended occurs, and there is a problem of deterioration in charging property. In an ionic conductive system in which an ionic conductive agent is blended, a polar polymer is required for the expression of ionic conductivity, and the higher the polarity, the harder and the elasticity of the polymer decreases.

  The problem to be solved by the present invention is to provide a conductive member for an electrophotographic apparatus that has low resistance, low hardness, low sag and excellent chargeability as compared with the prior art, and contamination is suppressed.

  In order to solve the above problems, a conductive member for an electrophotographic apparatus according to the present invention includes a conductive first polymer phase containing one or more polymers and one or more polymers, and the first polymer phase. A non-conductive second polymer phase that is present separately, a polymer component contained in the first polymer phase, and / or a polymer component contained in the second polymer phase And a compatibilizing agent comprising a polymer containing, and comprising a conductive elastic body layer composed of an interface phase existing between the first polymer phase and the second polymer phase. is there.

  The thickness of the interface phase is preferably in the range of 10 to 1000 nm. Within an arbitrary range of 5 μm □ of the conductive elastic layer, the area ratio of the first polymer phase to the total of the first polymer phase and the second polymer phase is within a range of 10 to 90%. preferable. The compatibilizing agent is preferably a polymer having at least one block selected from an acrylonitrile-butadiene copolymer block, a polyisoprene block, a block composed of a modified natural rubber component, and a block composed of a modified polyisoprene component. The compatibilizing agent may be composed of a polymer including both a constituent component of the polymer contained in the first polymer phase and a constituent component of the polymer contained in the second polymer phase.

  According to the conductive member for electrophotographic equipment according to the present invention, the conductive elastic layer has a conductive first polymer phase and a nonconductive second polymer phase, and the conductive elastic layer has a nonconductive phase. Therefore, low hardness and low sag, which cannot be obtained only by the conductive phase, are exhibited. The first polymer phase and the second polymer phase are uniformly dispersed (finely dispersed) at the toner size level by the compatibilizing agent, thereby exhibiting lower hardness and lower sag. In addition, since both phases are uniformly and finely dispersed, charge control at the toner size level is possible, resistance unevenness is suppressed, and excellent chargeability is exhibited. In addition, since the compatibilizer is present in the interface phase between the first polymer phase and the second polymer phase, the compatibilizer appearing on the surface of the conductive elastic layer is reduced, and contamination by the compatibilizer is suppressed. It is done.

  At this time, when the thickness of the interfacial phase is in the range of 10 to 1000 nm, low hardness and low sag characteristics due to the two phases of the conductive first polymer phase and the nonconductive second polymer phase are easily exhibited. .

  When the conductive first polymer phase and the non-conductive second polymer phase are present in a predetermined ratio within an arbitrary range of 5 μm □ of the conductive elastic layer, both phases are at the toner size level. In the case of (1) is uniformly dispersed (finely dispersed), lower hardness and lower sag are exhibited. Further, charge control at the toner size level is possible, resistance unevenness is suppressed, and excellent chargeability is exhibited.

  And if a compatibilizing agent consists of a specific polymer mentioned above, it will become still more low in hardness and low.

It is the external appearance schematic diagram (a) of the electroconductive apparatus roll for electrophotographic equipment which concerns on one Embodiment of this invention, and its AA sectional view (b). They are the external appearance schematic diagram (a) of the electroconductive apparatus electroconductive belt (endless belt) which concerns on one Embodiment of this invention, and its BB sectional drawing (b). It is a schematic diagram which shows the phase structure which expanded and showed the C1 part in FIG. 1, and the C2 part in FIG. It is the schematic diagram which showed the method to measure the area ratio of both the phases of the electroconductive 1st polymer phase in a conductive elastic body layer, and a nonelectroconductive 2nd polymer phase. It is a schematic diagram which shows the phase structure which concerns on another form. 3 is an enlarged cross-sectional photograph of a conductive elastic layer of Example 2. 3 is an enlarged cross-sectional photograph of a conductive elastic layer of Comparative Example 1.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  The electroconductive member for electrophotographic equipment according to the present invention (hereinafter sometimes referred to as the present electroconductive member) includes a conductive elastic layer made of an elastic body having conductivity. This conductive member is a conductive roll such as a charging roll, a developing roll, a transfer roll, and a toner supply roll used in an electrophotographic apparatus such as a copying machine, a printer, and a facsimile that employs an electrophotographic method, an intermediate transfer belt, paper It is suitable as an endless belt (conductive belt) such as a transfer conveyance belt.

  FIG. 1 shows a conductive roll for an electrophotographic apparatus according to an embodiment of the present invention, and FIG. 2 shows a conductive belt (an endless belt) for an electrophotographic apparatus according to an embodiment of the present invention. .

  As shown in FIG. 1, a conductive roll 10 for electrophotographic equipment according to an embodiment of the present invention (hereinafter simply referred to as a conductive roll 10) is disposed on a shaft body 12 and on the outer periphery of the shaft body 12. The conductive elastic body layer 14 is provided. The conductive elastic layer 14 is a base layer of the conductive roll 10, and a resistance adjustment layer, a surface layer, and the like may be provided on the outer periphery of the conductive elastic layer 14 as necessary.

  The shaft body 12 is not particularly limited as long as it has conductivity. Specific examples include solid bodies made of metal such as iron, stainless steel, and aluminum, and a cored bar made of a hollow body. You may apply | coat an adhesive agent, a primer, etc. to the surface of the shaft body 12 as needed. The adhesive, primer, etc. may be made conductive as necessary.

  As shown in FIG. 2, a conductive belt (endless belt) 20 for electrophotographic equipment (hereinafter sometimes simply referred to as a conductive belt 20) according to an embodiment of the present invention includes a conductive elastic layer 24. . The conductive elastic layer 24 is a base layer of the conductive belt 20, and a surface layer or the like may be provided on the outer periphery of the conductive elastic layer 24 as necessary.

  FIG. 3 shows an enlarged phase configuration of the C1 part in FIG. 1 and the C2 part in FIG. In this conductive member such as the conductive roll 10 and the conductive belt 20, the conductive elastic layer is separated from the conductive first polymer phase 1 and the first polymer phase 1 as shown in FIG. 3. The non-conductive second polymer phase 2 is present, and the interfacial phase 3 is present between the first polymer phase 1 and the second polymer phase 2.

  In FIG. 3, the conductive first polymer phase 1 is shown as a continuous phase (sea phase), and the nonconductive second polymer phase 2 is shown as a dispersed phase (discontinuous phase, island phase). The interfacial phase 3 is shown as a dispersed phase that continuously covers the periphery of the non-conductive second polymer phase 2. The interfacial phase 3 is a dispersed phase that continuously covers the entire periphery of the non-conductive second polymer phase 2 or a dispersed phase that continuously covers a part of the periphery of the non-conductive second polymer phase 2. There is.

  The conductive first polymer phase 1 contains one or more polymers. The one or more polymers are the first polymer phase 1 base polymer. The base polymer of the first polymer phase 1 may be a polar polymer, a nonpolar polymer, or a combination of a polar polymer and a nonpolar polymer. From the viewpoint of conductivity, it is preferable that the base polymer of the first polymer phase 1 is a polar polymer or includes a part of the polar polymer. When the base polymer of the first polymer phase 1 is a polar polymer, or includes a part of the polar polymer, a conductive agent is contained in the base polymer of the first polymer phase 1 if the desired conductivity is satisfied. May be dispersed, or may not be dispersed. As the conductive agent, an ionic conductive agent or an electronic conductive agent is used according to a conductive system (ionic conductive system or electronic conductive system). From the viewpoint of easily obtaining desired conductivity, it is preferable that the conductive agent is dispersed. When the base polymer of the first polymer phase 1 is a nonpolar polymer, or includes a part of the nonpolar polymer, the conductive polymer is contained in the base polymer of the first polymer phase 1 as long as the desired conductivity is satisfied. It is preferable that the agent is dispersed.

The conductive first polymer phase 1 is preferably made of a composition having a volume resistivity of 1 × 10 ⁸ Ω · cm or less from the viewpoint of conductivity. More preferably, the volume resistivity is 1 × 10 ⁶ Ω · cm or less, and still more preferably, the volume resistivity is 1 × 10 ⁵ Ω · cm or less. The volume resistivity of the composition constituting the conductive first polymer phase 1 is measured under a 23 ° C. and 53% RH environment in accordance with JIS K 6911 using a sheet sample obtained by molding into a sheet shape. can do. Moreover, it is preferable that the electroconductive 1st polymer phase 1 consists of a composition containing a electrically conductive agent from an electroconductive viewpoint.

  The non-conductive second polymer phase 2 contains one or more polymers. The one or more polymers are the second polymer phase 2 base polymer. The base polymer of the non-conductive second polymer phase 2 existing separately from the first polymer phase 1 is a polymer different from the base polymer of the first polymer phase 1. As long as the second polymer phase 2 is non-conductive, the base polymer of the second polymer phase 2 may be a polar polymer, a nonpolar polymer, or a polar polymer and a nonpolar polymer. A combination of these may be used. From the viewpoint of conductivity, it is preferable that the base polymer of the second polymer phase 2 is a nonpolar polymer or a part of the nonpolar polymer. As long as the second polymer phase 2 is non-conductive, a conductive agent may be dispersed in the base polymer of the second polymer phase 2, but from the viewpoint of conductivity, the base of the second polymer phase 2 It is preferable that the conductive agent is not dispersed in the polymer. Use of the electronic conductive agent necessary for the desired conductivity is not included in the non-conductive phase not functioning as the conductive phase when the electronic conductive agent is not mixed in the second polymer phase 2 but only in the first polymer phase 1. The amount can be reduced. Thereby, it is easy to make it low hardness and low cost.

  The nonconductive second polymer phase 2 preferably has a higher volume resistivity than the conductive first polymer phase 1 from the viewpoint of conductivity. The volume resistivity of the composition constituting the second polymer phase 2 is in accordance with JIS K 6911 using a sheet-like sample obtained by molding into a sheet shape, similarly to the composition constituting the first polymer phase 1. And can be measured in an environment of 23 ° C. and 53% RH. Moreover, it is preferable that the nonelectroconductive 2nd polymer phase 2 consists of a composition which does not contain a electrically conductive agent from an electroconductive viewpoint.

  In the conductive elastic layer, the conductive first polymer phase 1 has an increase in hardness due to the blended electronic conductive agent (conductive particles), a decrease in elastic recovery rate, and a deterioration in compression set. In addition, there is uneven resistance (deterioration of chargeability) due to poor dispersion of the blended electronic conductive agent (conductive particles). There is also a reduction in elasticity due to the polar polymer used. Therefore, when a conductive elastic body layer is constituted only by the conductive first polymer phase 1, low hardness and low sag are not satisfied.

  The non-conductive second polymer phase 2 has a smaller amount of conductive agent than that of the conductive first polymer phase 1 or no conductive agent. Further, the amount of the polar polymer used is smaller than that of the conductive first polymer phase 1, or the polar polymer is not used. For this reason, it is relatively excellent in flexibility. Then, the conductive elastic body layer has two phases of the conductive first polymer phase 1 and the nonconductive second polymer phase 2, and the nonconductive phase (second polymer phase 2) exists. , Low hardness and low sag, which cannot be obtained only by the conductive phase (first polymer phase 1), are exhibited. As the conductive phase (first polymer phase 1) and the non-conductive phase (second polymer phase 2) are finely dispersed, lower hardness and lower sag are exhibited.

  The polar polymer mentioned as the base polymer of the first polymer phase 1 and the second polymer phase 2 is a polymer having a polar group. Examples of the polar group include a chloro group, a nitrile group, a carboxyl group, and an epoxy group. Examples of the polar polymer include hydrin rubber, nitrile rubber (NBR), urethane rubber (U), acrylic rubber (a copolymer of acrylic ester and 2-chloroethyl vinyl ether, ACM), and chloroprene rubber (CR). Examples of hydrin rubber include epichlorohydrin homopolymer (CO), epichlorohydrin-ethylene oxide binary copolymer (ECO), epichlorohydrin-allyl glycidyl ether binary copolymer (GCO), epichlorohydrin-ethylene oxide-allyl glycidyl ether ternary. A copolymer (GECO) etc. are mentioned. These may be used alone as a polar polymer, or may be used in combination of two or more. Among these, hydrin rubber and nitrile rubber (NBR) are preferable from the viewpoint of lower resistance.

  The nonpolar polymer mentioned as the base polymer of the first polymer phase 1 or the second polymer phase 2 is a rubber having no polar group. Examples of the polar group include a chloro group, a nitrile group, a carboxyl group, and an epoxy group. Nonpolar polymers include natural rubber (NR), isoprene rubber (IR), hydrogenated isoprene rubber, butadiene rubber (BR), styrene-butadiene rubber (SBR), butyl rubber (IIR), ethylene-propylene rubber (EPM), Examples thereof include ethylene-propylene-diene terpolymer rubber (EPDM) and silicone rubber (Q). These may be used alone as a nonpolar polymer, or may be used in combination of two or more. Among these, natural rubber and isoprene rubber are preferable from the viewpoint of low hardness and easy reduction.

  As a more preferable combination of the base polymer (a) of the first polymer phase 1 and the base polymer (b) of the second polymer phase 2, (a) is hydrin rubber and / or nitrile rubber (NBR) (b ) Is natural rubber and / or isoprene rubber.

  The conductive first polymer phase 1 functions as a conductive phase. The non-conductive second polymer phase 2 functions as a flexible phase. The non-conductive second polymer phase 2 exists separately from the conductive first polymer phase 1. As described above, the conductive member is designed by separating the conductive phase and the flexible phase. In this case, for functional separation, different types of polymers are used for the conductive phase and the flexible phase so as not to mix with each other. Different types of polymers, especially combinations of polar and non-polar rubbers, are difficult to mix and phase separate. When the phase separation state is deteriorated, unevenness in the characteristics as a member increases.

  The interface phase 3 contains a compatibilizing agent. The compatibilizing agent has a role of a surfactant and prevents the phase separation of the first polymer phase 1 and the second polymer phase 2 from proceeding, for example, during the production process. Since the compatibilizing agent has an affinity for both phases that are not mixed with each other, the compatibilizing agent may be included in each phase. If the compatibilizing agent is contained in a large amount in the conductive first polymer phase 1 and the non-conductive second polymer phase 2, a large amount appears on the surface f (roll surface or belt surface) of the conductive member. Then, contamination such as toner fixation and sensitive material contamination is likely to occur. In the present conductive member, a compatibilizing agent that tends to be unevenly distributed between the first polymer phase 1 and the second polymer phase 2 is used. Thereby, the interface phase 3 is formed. Since the compatibilizing agent is present in the interface phase 3 between the first polymer phase 1 and the second polymer phase 2, the compatibilizing agent appearing on the surface f of the conductive elastic layer is reduced, and the compatibilizing agent is contaminated. Is suppressed.

  The compatibilizing agent is a polymer different from both the base polymer of the first polymer phase 1 and the base polymer of the second polymer phase 2. The compatibilizing agent is composed of a polymer containing either one or both of a constituent component of the polymer contained in the first polymer phase 1 and a constituent component of the polymer contained in the second polymer phase 2. Examples of the polymer component include an acrylonitrile-butadiene copolymer block, a polyisoprene block, a block composed of a modified natural rubber component, and a block composed of a modified polyisoprene component. The compatibilizer may be, for example, a polymer having one of the above-described polymer constituents, or may be a polymer having two or more. When the compatibilizing agent is a polymer having at least one block of the above-described polymer constituent components, the hardness and the spatiness are further reduced.

  Examples of the polymer having a block made of a modified natural rubber component include modified natural rubber. Examples of the modified natural rubber include epoxidized natural rubber, chlorinated natural rubber, and nitrified natural rubber (acrylonitrile natural rubber). Examples of the polymer having a block composed of a modified polyisoprene component include modified isoprene rubber. Examples of the modified isoprene rubber include epoxidized isoprene rubber, chlorinated isoprene rubber, nitrified isoprene rubber (acrylonitrile-ized isoprene rubber), maleic acid-modified isoprene rubber, and (meth) acrylic acid-modified isoprene rubber.

  The compatibilizing agent may be composed of a polymer containing both the constituent component of the polymer contained in the first polymer phase 1 and the constituent component of the polymer contained in the second polymer phase 2. Examples of such a polymer include a polymer having a block composed of a nitrile rubber component and a block composed of an isoprene rubber component.

  As the compatibilizing agent, one kind of the above-described polymers may be used alone, or two or more kinds may be used in combination. Among these, epoxidized natural rubber and epoxidized isoprene rubber are particularly preferable from the viewpoint of particularly excellent compatibilizing effect.

  The thickness of the interfacial phase 3 is preferably in the range of 10 to 1000 nm. The compatibilizer is in an appropriate amount, and the low hardness and low sag characteristics due to the two phases of the conductive first polymer phase 1 and the nonconductive second polymer phase 2 are easily exhibited. When the thickness of the interface phase 3 is sufficient, the amount of the compatibilizer can be reduced. The thickness of the interface phase 3 is more preferably in the range of 10 to 500 nm, more preferably in the range of 10 to 300 nm, and particularly preferably from the viewpoint that the low hardness and low sag characteristics due to the two phases are more easily exhibited. Is in the range of 10-200 nm. The thickness of the interfacial phase 3 can be adjusted by controlling the affinity of the compatibilizer for both phases (the first polymer phase 1 and the second polymer phase 2) and the blending amount.

  In the conductive elastic layer, the first polymer phase 1 and the second polymer phase 2 are preferably uniformly dispersed (finely dispersed). Since both phases are uniformly dispersed (finely dispersed) at the toner size level, lower hardness and lower sag are exhibited. Further, charge control at the toner size level is possible, resistance unevenness is suppressed, and excellent chargeability is exhibited.

  Specifically, the area ratio of the first polymer phase 1 to the total of the first polymer phase 1 and the second polymer phase 2 is within a range of 10 μm square (5 μm × 5 μm) of the conductive elastic layer. It is preferable to be within the range of 90%. In addition, the area ratio of the second polymer phase 2 is preferably within a range of 10 to 90%. Arbitrary means any place. The area ratio of both the first polymer phase 1 and the second polymer phase 2 is within an arbitrary range of 5 μm □. Specifically, as shown in FIG. 4, as shown in FIG. An arbitrary cross section is observed, an arbitrary 40 × 40 μm range in the cross section is divided into 64, 16 squares arranged in an oblique direction with diagonal lines are selected, and the first polymer phase 1 in each 5 × 5 μm square ( Alternatively, the area ratio of the second polymer phase 2) is measured, and 14 or more (8.5% or more) of the selected 16 cells is a corresponding value.

  When the area ratio of the first polymer phase 1 (conductive phase) is 10% or more within an arbitrary range of 5 μm □, the dispersibility of the first polymer phase 1 (conductive phase) becomes particularly good. If it does so, the influence of aggregation (dispersibility) of the electronic conductive agent in the 1st polymer phase 1 (conductive phase) will become especially small, and the dispersibility of the electronic conductive agent in a conductive elastic body layer will become especially favorable. As a result, resistance unevenness is further suppressed, and chargeability is particularly good. In addition, when the area ratio of the first polymer phase 1 (conductive phase) is 90% or less within an arbitrary range of 5 μm □, the first polymer phase 1 (conductive phase) is sufficiently small and the first polymer phase 1 (conductive) Phase) is dispersed in the toner size level. If it does so, the influence of aggregation (dispersibility) of the electronic conductive agent in the 1st polymer phase 1 (conductive phase) will become especially small, and the dispersibility of the electronic conductive agent in a conductive elastic body layer will become especially favorable. As a result, resistance unevenness is further suppressed, and chargeability is particularly good.

  When the area ratio of the conductive phase is in the range of 20 to 80% within an arbitrary range of 5 μm □ of the conductive elastic layer, the chargeability is further improved. Further, from the viewpoint of excellent chargeability, the area ratio of the conductive phase is more preferably in the range of 30 to 70%, and still more preferably in the range of 40 to 60%.

  Thus, in order to uniformly disperse (finely disperse) the first polymer phase 1 (conductive phase) and the second polymer phase 2 (non-conductive phase) at the toner size level, for example, the first polymer phase 1 The base polymer of the first polymer phase 1 (conductive phase) and the second polymer phase 2 (non-conductive phase) using a compatibilizing agent that improves the dispersibility of both the (conductive phase) and the second polymer phase 2 (non-conductive phase). It is conceivable to use a method such as adjusting the blending ratio of the base polymer of the conductive phase or kneading sufficiently to a desired degree of dispersion.

The conductive member preferably has a resistance in the range of 1 × 10 ² to 1 × 10 ⁹ Ω when 10 V is applied. It is easy to satisfy low hardness and low sag while ensuring the conductivity required for the electroconductive member for electrophotographic equipment. Low hardness and low sag are affected by an electronic conductive agent, a polar polymer, and the like that are blended to reduce resistance. From the viewpoint of conductivity, the resistance when 10 V is applied is more preferably 1 × 10 ⁷ Ω or less, and even more preferably 1 × 10 ⁶ Ω or less. From the viewpoint of low hardness and low sag, the resistance when 10 V is applied is more preferably 1 × 10 ³ Ω or more, and further preferably 1 × 10 ⁴ Ω or more.

  Examples of the ionic conductive agent include quaternary ammonium salts, quaternary phosphonium salts, borates, and surfactants. The content of the ionic conductive agent in the first polymer phase 1 (conductive phase) of the ionic conductive system is 0 with respect to 100 parts by mass of the base polymer of the first polymer phase 1 (conductive phase) from the viewpoint of low resistance, bleeding, and the like. It is preferable that it is in the range of 1 to 10 parts by mass. More preferably, it exists in the range of 0.5-5.0 mass parts.

  Examples of the electronic conductive agent include carbon black, graphite, potassium titanate, iron oxide, conductive titanium oxide, conductive zinc oxide, and conductive tin oxide. Among these, carbon black and graphite are preferable from the viewpoint of conductivity and the like. The content of the electronic conductive agent in the first polymer phase 1 (conductive phase) of the electronic conductive system is based on 100 parts by mass of the base polymer of the first polymer phase 1 (conductive phase) from the viewpoint of conductivity (low resistance) and the like. , 6 parts by mass or more is preferable. More preferably, it is 7 mass parts or more, More preferably, it is 8 mass parts or more. Moreover, it is preferable that it is 40 mass parts or less with respect to 100 mass parts of base polymers of the 1st polymer phase 1 (conductive phase) from viewpoints, such as low hardness and low sag. More preferably, it is 35 mass parts or less, More preferably, it is 30 mass parts or less.

  The conductive rubber elastic layer comprises a composition constituting the first polymer phase 1 (conductive phase), a composition constituting the second polymer phase 2 (non-conductive phase), and an interface phase 3 containing a compatibilizer. And a conductive composition containing at least a constituent composition. This conductive composition contains a vulcanizing agent (crosslinking agent), a vulcanization accelerator, a vulcanization aid (crosslinking aid), and the like as necessary. Further, one or more additives such as a bulking agent, a reinforcing agent, a processing aid, an antioxidant, a plasticizer, an ultraviolet absorber, and a lubricant can be contained.

  This conductive composition constitutes a composition constituting the first polymer phase 1 (conductive phase), a composition constituting the second polymer phase 2 (non-conductive phase), and an interface phase 3 containing a compatibilizing agent. And a vulcanizing agent (crosslinking agent), a vulcanization accelerator, a vulcanization aid (crosslinking aid), an additive, and the like, which are blended as necessary. Before preparing the conductive composition, the composition constituting the first polymer phase 1 (conductive phase) is premixed with a base polymer and a conductive agent and additives blended as necessary. Prepare. In addition, the composition constituting the second polymer phase 2 (non-conductive phase) is also prepared by mixing and kneading a base polymer and an additive to be blended as necessary before preparing the conductive composition. Prepare.

  The blend ratio of the base polymer (a) of the first polymer phase 1 (conductive phase) and the base polymer (b) of the second polymer phase 2 (non-conductive phase) is the same as that of the first polymer phase 1 (conductive phase) and the second polymer. From the standpoint that both phases 2 (non-conductive phase) are likely to be uniformly dispersed (finely dispersed) at the toner size level, the mass ratio is preferably in the range of a / b = 10/90 to 90/10. More preferably, it is in the range of a / b = 20/80 to 80/20, and further preferably in the range of a / b = 30/70 to 70/30.

  The blending amount of the compatibilizing agent is such that both the first polymer phase 1 (conductive phase) and the second polymer phase 2 (non-conductive phase) are easily dispersed (finely dispersed) at the toner size level. Within a range of 0.1 to 20 parts by mass with respect to a total of 100 parts by mass of the base polymer (a) of the first polymer phase 1 (conductive phase) and the base polymer (b) of the second polymer phase 2 (non-conductive phase) It is preferable that More preferably, it exists in the range of 0.5-15 mass parts, More preferably, it exists in the range of 1.0-10 mass parts.

  Examples of the vulcanizing agent (crosslinking agent) include sulfur and peroxide. Among the vulcanizing agents (crosslinking agents), a peroxide is more preferable from the viewpoint of being easily lowered. From the standpoint that the amount of the peroxide is easily reduced, the base polymer (a) of the first polymer phase 1 (conductive phase) and the base polymer (b) of the second polymer phase 2 (non-conductive phase) are used. It is preferable that it exists in the range of 0.5-7 mass parts with respect to a total of 100 mass parts. More preferably, it exists in the range of 1.0-5 mass parts.

  The peroxide as a vulcanizing agent (crosslinking agent) may be used by being supported on a carrier such as calcium carbonate. In this case, a carrier such as calcium carbonate remains in the conductive composition. As shown in FIG. 5, the carrier 4 such as calcium carbonate is collected in the first polymer phase 1 and the second polymer phase 2 by collecting the carrier 4 such as calcium carbonate in the interface phase 3 containing the compatibilizer. Therefore, the characteristics of the first polymer phase 1 and the second polymer phase 2 are more easily exhibited. Therefore, the type of the compatibilizing agent or the like is appropriately selected, and the carrier 4 such as calcium carbonate is collected in the interface phase 3 containing the compatibilizing agent.

The conductive elastic layer has excellent conductivity (low resistance), low hardness and low sag. From the viewpoint of conductivity, the resistance value of the conductive elastic body layer is preferably in the range of 1.0 × 10 ^{2 to} 1.0 × 10 ⁹ Ω. Moreover, it is preferable that MD-1 hardness of a conductive elastic body layer is 50 or less from a viewpoint of lower hardness than before. More preferably, it is 45 or less and 40 or less. From the viewpoint of lowering than before, the elastic recovery rate of the conductive rubber elastic layer is preferably 80% or more. More preferably, it is more than 80%, 85% or more, 90% or more. The MD-1 hardness is measured using a cantilever-type leaf spring type spring type hardness tester (manufactured by Kobunshi Keiki Co., Ltd., “Micro Rubber Hardness Tester MD-1 Type”). The MD-1 hardness measurement value is a value measured with a thickness of the polymer to be measured of 1 to 2 mm. The elastic recovery rate is measured using a microhardness meter (Fischer, Fischerscope H100C) in accordance with ISO14577-1.

  Although the thickness of a conductive elastic layer is not specifically limited, Usually, it forms in about 0.1-10 mm, Preferably it is 1-5 mm. The conductive elastic layer may be a solid non-foamed material or a foamed material such as a sponge.

  The conductive roll 10 can be manufactured as follows, for example. First, an adhesive composition is applied to the outer periphery of the shaft body 12 as necessary. Next, the conductive composition is formed into a layer on the outer periphery of the applied adhesive composition. The conductive composition can be molded by extrusion molding or molding. The conductive composition is crosslinked and cured by heating at the time of extrusion molding or molding. Thereby, the electroconductive roll 10 which has the electroconductive elastic body layer 14 in the outer periphery of the shaft body 12 is obtained.

  The outer periphery of the conductive elastic layer 14 is provided with surface characteristics (low friction, releasability, chargeability, etc.) of the conductive roll 10 to protect the surface of the conductive elastic layer 14 as necessary. For the purpose of, for example, a surface layer may be formed. Further, an intermediate layer such as a resistance adjusting layer for adjusting the resistance of the entire conductive roll 10 may be formed below the surface layer on the outer periphery of the conductive elastic layer 14.

  The main material for forming the surface layer is not particularly limited, and examples thereof include polyamide (nylon) -based, acrylic-based, urethane-based, silicone-based, and fluorine-based polymers. These polymers may be modified. Examples of the modifying group include an N-methoxymethyl group, a silicone group, and a fluorine group.

The surface layer, for imparting conductivity, carbon black, _{graphite, c-TiO 2, c-} ZnO, c-SnO 2 (c- means conductive.), Ion conductive agent (quaternary ammonium salt, Conventionally known conductive agents such as borates and surfactants can be appropriately added. Moreover, you may add various additives suitably as needed.

  In order to form the surface layer, a surface layer forming composition is used. The composition for surface layer formation consists of what contains the said main material, a electrically conductive agent, and the other additive contained as needed. Additives include lubricants, vulcanization accelerators, anti-aging agents, light stabilizers, viscosity modifiers, processing aids, flame retardants, plasticizers, foaming agents, fillers, dispersants, antifoaming agents, pigments, release agents. Examples include molds.

  From the viewpoint of adjusting the viscosity, the surface layer-forming composition is an organic solvent such as methyl ethyl ketone, toluene, acetone, ethyl acetate, butyl acetate, methyl isobutyl ketone (MIBK), THF, or DMF, or a water-soluble solution such as methanol or ethanol. A solvent such as a reactive solvent may be included as appropriate.

  The surface layer can be formed by a method such as coating the surface-forming composition on the outer periphery of the conductive elastic layer 14. As a coating method, various coating methods such as a roll coating method, a dipping method, and a spray coating method can be applied. The coated surface layer may be subjected to ultraviolet irradiation or heat treatment as necessary.

The thickness of the surface layer is usually set to 0.01 to 100 μm, 0.1 to 20 μm, or 0.3 to 10 μm. The volume resistivity of the surface layer is usually set to 10 ⁴ to 10 ⁹ Ω · cm, 10 ⁵ to 10 ⁸ Ω · cm, or 10 ⁶ to 10 ⁷ Ω · cm.

  Further, instead of forming the surface layer, surface modification may be performed on the intermediate layer such as the conductive elastic layer 14 or the resistance adjusting layer, so that the surface characteristics equivalent to the formation of the surface layer can be obtained. . Surface modification methods include UV or electron beam irradiation, surface layer unsaturated bonds and surface modifiers that can react with halogens, such as isocyanate groups, hydrosilyl groups, amino groups, halogen groups, thiol groups, etc. Examples thereof include a method of contacting with a compound containing a reactive group.

  The conductive belt 20 is formed by coating a conductive composition on the surface of a mold (cylindrical substrate) by a coating method such as spray coating, and heating the coating to a predetermined temperature (preferably 150 to 300 ° C.). It can be formed by drying for a time (preferably 3 to 6 hours). The outer periphery of the conductive elastic layer 24 is provided with surface characteristics (low friction, releasability, chargeability, etc.) of the conductive belt 20 that protect the surface of the conductive elastic layer 24 as necessary. For the purpose of, for example, a surface layer may be formed. Examples of the surface layer material include silicone resins, fluorine resins, urethane resins, acrylic resins, polyamide resins, and the like.

  As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of this invention. For example, in FIG. 1, the conductive elastic layer is shown as the base layer of the conductive roll, but may be a surface layer. Similarly, in FIG. 2, the conductive elastic layer is shown as the base layer of the conductive belt, but it may be a surface layer.

  In FIG. 3, the conductive first polymer phase 1 is shown as a continuous phase (sea phase), and the non-conductive second polymer phase 2 is shown as a dispersed phase (discontinuous phase, island phase). However, the first polymer phase 1 may be a dispersed phase (non-continuous phase, island phase), and the second polymer phase 2 may be a continuous phase (sea phase). In this case, the interfacial phase 3 is a dispersed phase that continuously covers the periphery of the conductive first polymer phase 1. Further, both the first polymer phase 1 and the second polymer phase 2 may be continuous phases (sea phases).

  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, this invention is not limited to this structure.

Details of the materials used are shown below.
Nitrile rubber (NBR): JSR "N237H"
Isoprene rubber (IR): “JSR IR2200” manufactured by JSR
・ Natural rubber (NR): International standard grade RSS1 ・ Epoxidized natural rubber (epoxidized NR): “EPOXYPRENE50” (50% modified product) manufactured by Muang Mai Guthrie Public Company Limited
Other modified epoxidized natural rubbers (epoxidized NR) were prepared with reference to WO2013 / 133380A1.
-Block copolymer of NBR and IR (NBIR): “Nipol DN1201” manufactured by Zeon Corporation
・ Ionic conductive agent: Tetrabutylammonium bromide, “TBAB-100” manufactured by Lion Akzo Co., Ltd.
Carbon black (electronic conductive agent): “Printex XE2B” manufactured by Degussa, BET specific surface area 950 (m ² / g)
・ Peroxide vulcanizing agent: “Park Mill D40” manufactured by NOF Corporation

(Examples 1-5, Comparative Examples 1-2)
<Preparation of conductive composition>
Each component was mix | blended with the compounding composition (mass ratio) shown in Table 1, and it stirred and mixed with the stirrer and prepared the electrically conductive composition.

<Preparation of conductive roll>
A core metal (diameter 6 mm) is set on the center axis of a molding die having a cylindrical molding cavity of 9 mm in diameter, and the conductive composition is injected into the molding die, and heated and crosslinked at 160 ° C. for 30 minutes. After cooling and demolding, a conductive elastic layer having a thickness of 1.5 mm was formed on the outer periphery of the cored bar. This produced the electroconductive roll.

  Observation of the phase structure, elastic recovery, MD-1 hardness, and resistance value of the conductive elastic layer of each conductive roll obtained were measured. In addition, the characteristics of each product such as setability, initial and durable fogging, image density, and toner fixing property were evaluated. These results are shown in Table 1. The set property is affected by the sagability of the conductive elastic layer. The initial fogging property is affected by the charging property (area ratio of each phase of the conductive elastic layer). The durability fogging property is affected by the hardness of the conductive elastic layer. The image density is affected by the resistance value (conductivity) of the conductive elastic layer.

  As a representative example, a cross-sectional photograph of the conductive elastic layer of the conductive roll of Example 2 is shown in FIG. 6, and a cross-sectional photograph of the conductive elastic layer of the conductive roll of Comparative Example 1 is shown in FIG. FIG. 6B is an enlarged photograph of a portion surrounded by a square in FIG. FIG. 6C is an enlarged photograph of a portion surrounded by a square in FIG. 6 and 7, the relatively light colored portion is the first conductive polymer phase, and the relatively dark portion is the non-conductive second polymer phase, as shown in FIG. The phase present around the second polymer phase is the interfacial phase. In the lower right of each photo, a scale is shown to indicate the size of the phase.

(Interfacial phase thickness)
An arbitrary cross section of the conductive elastic body layer was observed, and the thickness of the interface phase observed in an arbitrary 40 × 40 μm range in the cross section was measured.

(Area ratio)
Observe an arbitrary cross section of the conductive elastic layer, as shown in FIG. 4, divide an arbitrary 40 × 40 μm range in the cross section into 64, and select 16 cells arranged in an oblique direction with diagonal lines; Measure the area ratio of the first polymer phase (conductive phase) and the second polymer phase (non-conductive phase) within each 5 × 5 μm square, and 14 squares or more (8.5% or more) out of 16 squares Value. The case where the area ratio of the first polymer phase to the total of the first polymer phase and the second polymer phase is in the range of 10 to 90% was “◯”, and the outside of the range was “x”.

(Elastic recovery rate)
In accordance with ISO14577-1, the surface of the conductive elastic layer was measured under the following measurement conditions using a microhardness meter (Fischer scope H100C, manufactured by Fischer), and ηIT [%] was determined. That is, when a microhardness meter is used and the indenter is pushed into the material surface with a constant test load, the total mechanical work Wtotal of the dent shown during the indentation work is very small as the plastic deformation work Wplast of the dent. Only part is consumed. When the test load is unloaded, the remaining part is released as the elastic return deformation work Welast of the recess. If this mechanical work is defined as W = ∫Fdh, the relationship is as follows. The elastic recovery rate was 80% or more low, and less than 80% high.
ηIT [%] = Welast / Wtotal
However, Wtotal = Welast + Wplast
<Measurement conditions>
Indenter: Square-angled diamond indenter with a face angle of 136 ° Initial load: 0 mN
Maximum indentation load: 20mN (constant load)
Maximum load arrival time: 0.25 to 10 sec
Maximum load holding time: 5 sec
Drawing time: 0.25-10sec
Measurement temperature: 25 ° C

(MD-1 hardness (micro rubber hardness))
Conductive elasticity of each conductive roll held using a cantilever-type leaf spring type spring type hardness tester (manufactured by Kobunshi Keiki Co., Ltd., “Micro Rubber Hardness Tester MD-1”) Measurement was performed by bringing the tip of the push needle of the hardness tester into contact with the surface of the center portion in the axial direction of the body layer, further pressing the tester vertically with a load of 33.85 g, and immediately reading the scale. . An MD-1 hardness of 50 or less was defined as low hardness, and a hardness exceeding 50 was defined as high hardness.

(Resistance value)
With the both ends of the conductive roll pressed against the metal roll (diameter: 30 mm) with a predetermined load, the conductive roll was rotated by rotating the metal roll at a predetermined rotation speed. While maintaining this state (while rotating both the metal roll and the conductive roll), a voltage of 10 V is applied between the ends of the conductive roll and the metal roll, the value of the flowing current is measured, and the electric resistance value (roll Resistance: Ω) was obtained. When the resistance value exceeds 1 × 10 ⁹ Ω, the resistance is high, and when the resistance value is in the range of 1 × 10 ² Ω to 1 × 10 ⁹ Ω, the resistance is low.

(Set property)
The conductive roll was assembled to the cartridge, sealed, and left in a normal temperature and humidity environment for 14 days. Thereafter, the image was printed in a normal temperature and humidity environment. The case where a streak-like defect was seen in the drawing was judged as “failed” “x”, and the case where it was not seen was judged as “passed”. Further, the roundness of the conductive elastic layer was measured with Roncom, and the amount of sag from the dent amount from the roundness was measured. When the amount of sag is 5 μm or less, it is set as low, and when it is over 5 μm, it is set as high. Of the acceptable “◯” in the setting property, the case where the amount of sag was 2 μm or less was particularly good “◎”.

(Initial fogging)
A conductive roll was assembled in the cartridge, and a white solid image was printed. The density was measured with a white photometer, and the initial fog was good “◯” if it was within the range of 1.40 to 1.46 at any nine points, and it was judged as “bad” if it was outside the range. Among the good initial fogging “◯”, those with white light intensity in the range of 1.43 to 1.45 at any nine points were particularly good “◎”.

(Durable fogging)
The conductive roll was assembled in the cartridge, and allowed to stand for 12 hours or more in a low-temperature and low-humidity environment (15 ° C., humidity 10%). Then, in this environment, 10,000 sheets were endured with 5% printing. Thereafter, the density was measured with a white photometer, and if any nine points were in the range of 1.40 to 1.46, the durability fogging was good “◯”, and if it was out of the range, it was judged as “poor”. Among the “◯” with good durability fogging, those with white light intensity in the range of 1.43 to 1.45 at any nine points were particularly good “「 ”.

(Image density)
A conductive roll was assembled in the cartridge, and a black solid image was printed. The density was measured with a white photometer, and if it was within the range of 1.0 to 2.0 at any nine points, it was judged as “good”, and if it was out of the range, it was judged as “bad”. Among the images with good image density “◯”, those with white light intensity in the range of 1.3 to 1.6 at any 9 points were rated particularly good “「 ”.

(Toner adhesion)
The conductive roll was assembled to the cartridge, and only one page was printed with a solid image, and then left for 14 days in a normal temperature and humidity environment. Then, the conductive roll was taken out and the surface was air blown. The case where streaky toner sticking was found on the surface of the conductive roll was judged as “failed”, and the case where it was not seen was judged as “good”.

  In Comparative Example 1, as shown in FIG. 7, in the conductive elastic layer, the first polymer phase (conductive phase) and the second polymer phase (non-conductive phase) exist, but the interface phase does not exist. For this reason, in Comparative Example 1, toner adhesion (contamination) is not suppressed. Further, the area ratio of the first polymer phase (conductive phase) is large in an arbitrary range of 5 μm □ of the conductive elastic layer, and the first polymer phase (conductive phase) is not dispersed in the toner size level. For this reason, the dispersibility of the electronic conductive agent in the conductive elastic layer is poor due to the influence of the aggregation (dispersibility) of the electronic conductive agent in the first polymer phase (conductive phase). As a result, resistance unevenness occurs, charging property is poor, and initial fogging is not satisfactory. Further, the elastic recovery rate is low and the setability is not satisfied.

  On the other hand, in the example, as shown in FIG. 6, in the conductive elastic body layer, the first polymer phase (conductive phase) and the second polymer phase (non-conductive phase), as well as the first polymer phase (conductive phase) and the second polymer phase (non-conductive phase). An interfacial phase containing a compatibilizing agent exists between the two polymer phases (non-conductive phase). For this reason, in the embodiment, toner adhesion (contamination) is suppressed. Further, the area ratio of the first polymer phase (conductive phase) is in a desired range in an arbitrary range of 5 μm □ of the conductive elastic layer, and the first polymer phase (conductive phase) as shown in FIG. And the second polymer phase (non-conductive phase) are uniformly dispersed (finely dispersed) at the toner size level, so that the conductive elastic layer has excellent dispersibility of the conductive agent and excellent chargeability. Thereby, initial fogging is satisfied. In addition, since it has a low hardness, a low sag, and a low resistance, it also satisfies setability, image density and durability fogging.

  And from an Example, when the thickness of an interface phase exists in the range of 10-300 nm, it can be made low hardness and low sag.

  As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to the said Example at all, A various change is possible in the range which does not deviate from the summary of this invention.

1 First polymer phase (conductive phase)
2 Second polymer phase (non-conductive phase)
DESCRIPTION OF SYMBOLS 3 Interface phase 10 Conductive roll 12 for electrophotographic apparatuses Shaft body 14 Conductive elastic body layer 20 Conductive belt 24 for electrophotographic apparatuses Conductive elastic body layer

Claims (5)

A conductive first polymer phase containing one or more polymers;
A non-conductive second polymer phase containing one or more polymers and present separately from the first polymer phase;
A compatibilizing agent comprising a polymer containing one or both of a constituent component of the polymer contained in the first polymer phase and a constituent component of the polymer contained in the second polymer phase, and the first polymer phase And an interfacial phase present between the second polymer phase;
A conductive member for an electrophotographic apparatus, comprising a conductive elastic layer composed of:   The electroconductive member for electrophotographic equipment according to claim 1, wherein the thickness of the interfacial phase is in the range of 10 to 1000 nm.   Within an arbitrary range of 5 μm □ of the conductive elastic layer, an area ratio of the first polymer phase to a total of the first polymer phase and the second polymer phase is in a range of 10 to 90%. The electroconductive member for electrophotographic equipment according to claim 1, wherein the electroconductive member is electroconductive.   The compatibilizer is a polymer having at least one block selected from an acrylonitrile-butadiene copolymer block, a polyisoprene block, a block composed of a modified natural rubber component, and a block composed of a modified polyisoprene component. The electroconductive member for electrophotographic equipment according to any one of claims 1 to 3.   5. The compatibilizing agent comprises a polymer containing both a polymer component contained in the first polymer phase and a polymer component contained in the second polymer phase. The electroconductive member for electrophotographic equipment according to claim 1.