JP5049627B2 - Ultraviolet curable conductive composition, electrophotographic apparatus member, electroconductive roll for electrophotographic apparatus, and electroconductive belt for electrophotographic apparatus - Google Patents

Description

  The present invention relates to an ultraviolet curable conductive composition, a member for electrophotographic equipment, a conductive roll for electrophotographic equipment, and a conductive belt for electrophotographic equipment.

  In recent years, electrophotographic apparatuses such as copying machines, printers, and facsimiles that employ an electrophotographic system have been widely used. In these electrophotographic apparatuses, a photosensitive drum is usually incorporated.

  Around the photosensitive drum, various conductive rolls such as a charging roll, a developing roll, a toner supply roll and a transfer roll are disposed. In addition to the conductive roll, a conductive belt such as a transfer belt is also provided inside the electrophotographic apparatus.

  The conductive roll usually has one or more conductive elastic layers on the outer periphery of the cored bar. As the conductive elastic layer material, a rubber-based conductive composition in which a conductive agent or a filler is blended with rubber such as silicone rubber or hydrin rubber has been the mainstream.

  Recently, as shown in Patent Document 1, for example, it has been proposed to use an ultraviolet curable resin paint as a conductive elastic layer material.

JP 2006-184895 A

  However, the rubber-based conductive composition that has been widely used as the conductive elastic layer material has the following problems.

  That is, in recent years, electrophotographic equipment has been improved in speed and image quality. For this reason, members for electrophotographic equipment such as conductive rolls incorporated therein are also required to have characteristics sufficient for high speed and high image quality.

  For example, in order to reduce stress on the toner, the conductive elastic layer of the conductive roll is required to have a low hardness. In addition, the conductive elastic layer of the conductive roll is required to have good sag resistance in order to ensure a nip width with respect to the photosensitive drum and to supply a stable charge.

  When silicone rubber is used, the hardness can be reduced, and good sag resistance can be obtained. However, in this case, an electronic conductive agent must be kneaded into the rubber in order to impart conductivity. Therefore, the dispersibility of the electronic conductive agent is poor, and the electric resistance tends to be uneven.

  On the other hand, since hydrin rubber is semiconductive, it is easy to make electric resistance uniform. However, hydrin rubber is high in hardness and has poor sag resistance.

  As described above, it has been difficult to obtain a conventional rubber-based conductive composition having a low hardness, a set resistance, and a good uniformity in electrical resistance.

  In addition, the rubber-based conductive composition basically needs to be molded by molding, extrusion molding, or the like. As a result, mold costs and mold maintenance costs are incurred, resulting in high manufacturing costs. Moreover, in order to make extrusion easy, it is necessary to fill with a high amount of filler, which prevents a reduction in hardness and deteriorates the settling resistance.

  The present invention has been made in view of the above circumstances, and the problem to be solved by the present invention is an ultraviolet curing capable of forming a cured product having a low hardness, a settling resistance, and an excellent electrical resistance uniformity. It is to provide a type conductive composition.

In order to solve the above problems, the ultraviolet curable conductive composition according to the present invention is:
(A) One or more photopolymerizable monomers selected from the following (a1) and (a2);
(A1) Monofunctional first photopolymerizable monomer having an ethylene oxide unit introduced into the molecular structure (a2) A monofunctional first photopolymerizable monomer having an ethylene oxide unit introduced into the molecular structure and having a urethane bond 2 photopolymerizable monomer (B) containing a photopolymerization initiator,
Further containing a polyfunctional photopolymerizable monomer having an ethylene oxide unit introduced into the molecular structure;
The gist is that the content of the component (A) in the polymerization component contained in the composition is 60% by weight or more.

  Here, the ultraviolet curable conductive composition may further contain (C) an ion conductive agent.

  Moreover, the said 2nd photopolymerizable monomer is good in the said ethylene oxide unit being introduce | transduced through the said urethane bond.

  The first photopolymerizable monomer and the second photopolymerizable monomer may be monofunctional (meth) acrylate.

  At this time, the polyfunctional photopolymerizable monomer preferably has a molecular weight in the range of 200 to 20,000.

  The polyfunctional photopolymerizable monomer is preferably a polyfunctional (meth) acrylate.

  Moreover, the durometer type A hardness after hardening of the said composition is good in the range of 0-50.

  The gist of the member for an electrophotographic apparatus according to the present invention is that it has a portion formed by curing the ultraviolet curable conductive composition.

  A conductive roll for electrophotographic equipment according to the present invention is characterized by having a layer formed by curing the ultraviolet curable conductive composition.

  The electroconductive belt for electrophotographic equipment according to the present invention is summarized as having a layer formed by curing the ultraviolet curable conductive composition.

The ultraviolet curable conductive composition according to the present invention contains (A) a specific amount of one or more photopolymerizable monomers selected from the following (a1) and (a2).
(A1) A monofunctional first photopolymerizable monomer having an ethylene oxide unit introduced into the molecular structure (a2) A monofunctional first photopolymerizable monomer having an ethylene oxide unit introduced into the molecular structure and having a urethane bond Two-photopolymerizable monomer

  Therefore, a cured product obtained by curing this composition is excellent in low hardness, resistance to stickiness, and uniformity of electrical resistance as compared with a molded product made of a conventional silicone rubber-based or hydrin rubber-based conductive composition.

  Moreover, the said ultraviolet curable conductive composition has as a main component the photopolymerizable monomer which is low molecular weight compared with a polymer. Therefore, the viscosity can be reduced, and the handleability and the like are good.

  Moreover, the said ultraviolet curable conductive composition does not have a rubber kneading | mixing process at the time of the manufacture like the conventional rubber-type conductive composition. Therefore, the contamination defect by rubber kneading can be eliminated.

  Moreover, the said ultraviolet curable conductive composition can be shape | molded by the coating method irrespective of a shaping | molding die. Therefore, mold costs, mold maintenance costs, etc. do not occur, and the manufacturing cost can be reduced accordingly.

  Here, when the said ultraviolet curable conductive composition contains the (C) ionic conductive agent, it becomes easy to adjust the electrical resistance of hardened | cured material.

  When the ultraviolet curable conductive composition contains the component (a2), a strong urethane bond is introduced into the cured product. Therefore, it becomes easy to ensure the strength and elongation of the cured product.

  In addition, when the first photopolymerizable monomer and the second photopolymerizable monomer are monofunctional (meth) acrylates, there are relatively many types, and the range of material selection is widened. Therefore, it becomes easy to adjust the balance of the viscosity of the composition that is an uncured product, the hardness of the cured product, the degree of stickiness, and the electrical resistance.

  Moreover, when the said ultraviolet curable conductive composition further contains the polyfunctional photopolymerizable monomer into which the ethylene oxide unit was introduce | transduced in the molecular structure, it becomes easy to improve a lettuce resistance.

  In particular, when the molecular weight of the polyfunctional photopolymerizable monomer is in the range of 200 to 20000, a significant increase in viscosity is easily suppressed.

  In addition, when the polyfunctional photopolymerizable monomer is a polyfunctional acrylate, the number of types is relatively large, and the range of material selection is widened. Therefore, it becomes easy to adjust the degree of stickiness.

  When the durometer type A hardness after curing of the composition is in the range of 0 to 50, for example, when applied to the conductive elastic layer of the conductive roll for electrophotographic equipment, the stress on the toner can be reduced. There are advantages such as being easy to contribute to higher image quality and higher durability.

  On the other hand, the electrophotographic apparatus member according to the present invention has a portion formed by curing the ultraviolet curable conductive composition.

  Therefore, if this is applied to a conductive elastic layer such as various conductive rolls and conductive belts used in electrophotographic equipment, for example, the conductive roll is excellent in low hardness, sag resistance, and uniformity of electrical resistance. A conductive belt is obtained.

  Hereinafter, the ultraviolet curable conductive composition according to the present embodiment (hereinafter sometimes referred to as “the present composition”) and the electrophotographic apparatus member according to the present embodiment will be described.

1. The present composition The present composition contains (A) a photopolymerizable monomer and (B) a photopolymerization initiator as essential components. Hereinafter, each component will be described in detail.

  In the present composition, the component (A) comprises one or more selected from (a1) the first photopolymerizable monomer and (a2) the second photopolymerizable monomer.

  (A1) The first photopolymerizable monomer is a monofunctional photopolymerizable monomer in which an ethylene oxide unit is introduced into the molecular structure.

  In addition to the ethylene oxide unit, the first photopolymerizable monomer may have one or more other units introduced into the molecular structure.

  Examples of the other unit include, for example, an alkylene oxide unit having 3 to 20 carbon atoms, a trimethylolpropane unit, a pentaerythritol unit, an ethylhexyl carbitol unit, a glycerin unit, a nonylphenol unit, a paracumylphenol unit, a bisphenol A unit, Examples include units containing cyclic unsaturated structures such as styrene oxide units, isocyanuric acid units, bisphenol F units, phthalic acid units, and phenoxy units.

  As content of the ethylene oxide unit in a 1st photopolymerizable monomer, from a viewpoint of becoming easy to make the electrical resistance of hardened | cured material low, Preferably it exists in the range of 1 to 98 weight%, More preferably, it is 20 to 98. It is good to be in the range of wt%, more preferably in the range of 40 to 98 wt%.

  In addition, content of an ethylene oxide unit can be measured using NMR (nuclear magnetic resonance apparatus) etc., for example. This also applies to monomers and oligomers described later.

  The first photopolymerizable monomer is a compound having one functional group in the monomer. Specific examples of the functional group include an acryloyl group, a methacryloyl group, an allyl group, a vinyl group, a thiol group, a vinyl ether group, an epoxy group, a glycidyl ether group, and a group having an intramolecular double bond. Can do.

  As the first photopolymerizable monomer, there are comparatively many types and a wide range of material selection, and it is easy to adjust the viscosity of the composition, the hardness of the cured product, the degree of stickiness, the electric resistance, etc. Therefore, monofunctional acrylates and monofunctional methacrylates in which ethylene oxide units are introduced into the molecular structure are preferred. More preferably, it is a monofunctional acrylate.

  Specific examples of the first photopolymerizable monomer include, for example, phenoxyethylene oxide modified acrylate (Chemical Formula 1 in Table 1), nonylphenol ethylene oxide modified acrylate (Chemical Formula 2 in Table 1), methoxyethylene oxide modified acrylate (Table 1). Chemical formula 3 etc.), ethoxyethylene oxide modified acrylate (Chemical formula 4 etc. in Table 1), 2-ethylhexyl ethylene oxide modified acrylate (Chemical formula 5 etc. in Table 1), butoxyethylene oxide modified acrylate (Chemical formula 6 etc. in Table 1), ethylene oxide modified cresol acrylate ( Examples of the chemical formula 7 in Table 1). These can be used alone or in combination of two or more.

  On the other hand, the (a2) second photopolymerizable monomer is a monofunctional photopolymerizable monomer having an ethylene oxide unit introduced into the molecular structure and a urethane bond.

  This second photopolymerizable monomer is different from the first photopolymerizable monomer (a1) which does not have a urethane bond in that it has a urethane bond. In addition to the ethylene oxide unit, one or more other units may be introduced into the molecular structure, the content of the ethylene oxide unit, and the type of the functional group are described in the first of (a1). The same as the photopolymerizable monomer.

  When this composition contains this (a2) component, a strong urethane bond is introduce | transduced in the hardened | cured material by this composition. Therefore, it becomes easy to improve mechanical properties such as strength and elongation of the cured product.

  From the viewpoint of compatibility with the first photopolymerizable monomer, conductivity, and the like, the second photopolymerizable monomer preferably has an ethylene oxide unit introduced through a urethane bond.

  As the second photopolymerizable monomer, there are relatively many types and a wide range of material selection, and it is easy to adjust the viscosity of the composition, the hardness of the cured product, the degree of stickiness, the electrical resistance, etc. Therefore, monofunctional acrylates and monofunctional methacrylates in which ethylene oxide units are introduced into the molecular structure and have a urethane bond are preferable. More preferably, it is a monofunctional acrylate.

  A monofunctional (meth) acrylate having a urethane bond, for example, reacts a monomer containing a hydroxyl group and a (meth) acryloyl group with an isocyanate to synthesize an acrylate-added isocyanate, and an ethylene oxide unit in the molecular structure. It can be obtained, for example, by reacting with the contained polyol.

  At the time of synthesis, one or more of various urethanization catalysts, chain extenders, amines, stabilizers, fillers and the like can be added as necessary.

  Specific examples of the monomer containing a hydroxyl group and a (meth) acryloyl group include, for example, 2 hydroxyethyl acrylate, 2 hydroxypropyl acrylate, 4 hydroxybutyl acrylate, 2 hydroxy 3 phenoxypropyl acrylate, and 2 hydroxy 3 acryloyloxypropyl. Examples thereof include hydroxy acrylate such as acrylate. These can be used alone or in combination of two or more.

  Specific examples of the isocyanate include tolylene diisocyanate, 4,4, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and methylene bis 4 cyclohexyl diisocyanate. These can be used alone or in combination of two or more. In addition, a modified product of the above isocyanate or a prepolymerized material may be used.

  Specific examples of the polyol containing an ethylene oxide unit in the molecular structure include polyethylene glycol, diethylene glycol, ethylene oxide-modified polypropylene glycol, and the like. These can be used alone or in combination of two or more.

  The synthesis only needs to be finally a monofunctional (meth) acrylate, and together with the ethylene oxide unit, it is possible to connect an isocyanate and copolymerize with another polyol. Examples of the copolymer component include silicone polyols, fluorine polyols, carbonate polyols, polyols that do not contain ethylene oxide units in the molecular structure, and the like. These may be used alone or in combination of two or more.

  Specific examples of the second photopolymerizable monomer include monomers represented by chemical formula 8, chemical formula 9, chemical formula 10, chemical formula 11 and the like in Table 2. These can be used alone or in combination of two or more.

  According to the above (A) photopolymerizable monomer, an ethylene oxide unit can be introduced into the side chain of the polymer which is a cured product.

  Here, from the viewpoint of making the composition low in hardness, good in set resistance and uniformity in electrical resistance after curing, the present composition is composed of the component (A) in the polymerization component contained in the composition. Content is 60 weight% or more.

  The content of the component (A) is preferably 65% by weight or more, more preferably 70% by weight, from the viewpoints of lowering the altitude and lowering the electric resistance.

  In addition, although the said polymerization component is specifically the said (A) component contained in this composition, when a monomer other than (A) component and an oligomer component are added, these are also contained.

  The present composition may contain other photopolymerizable monomers and photopolymerizable oligomers in addition to the component (A).

  Examples of other components include polyfunctional photopolymerizable monomers in which ethylene oxide units are introduced into the molecular structure and polyfunctional photopolymerizable oligomers in which ethylene oxide units are introduced into the molecular structure. can do. In the case of containing this, the settling resistance of the cured product can be improved.

  In addition to the ethylene oxide unit, one or more other units may be introduced into the molecular structure, and the type of functional group conforms to (A) the photopolymerizable monomer.

  The polyfunctional photopolymerizable monomer / oligomer is a compound having two or more functional groups in the molecule. The number of functional groups is not particularly limited, but the larger the number, the better the anti-sagging effect.

  The polyfunctional photopolymerizable monomer / oligomer has a molecular weight (number average molecular weight in the case of an oligomer), preferably from 200 to 200, from the viewpoint of suppressing an increase in the viscosity of the composition and improving the handleability. It is good in the range of 20000, More preferably, it exists in the range of 500-10000, More preferably, it exists in the range of 1000-5000.

  Specific examples of the polyfunctional photopolymerizable monomer / oligomer include, for example, ethylene oxide diacrylate, ethylene oxide-modified glycerin triacrylate, ethylene oxide-modified pentaerythritol tetraacrylate, ethylene oxide propylene oxide-modified diacrylate, and isocyanuric acid ethylene oxide-modified triacrylate. Examples thereof include polyfunctional (meth) acrylates in which ethylene oxide units are introduced into the molecular structure, such as diethylene glycol diglycidyl ether diacrylate and ethylene oxide-modified trimethylolpropane triacrylate. These can be used alone or in combination of two or more.

  Moreover, as another component, the monofunctional photopolymerizable monomer in which the ethylene oxide unit is not introduce | transduced in molecular structure can be illustrated, for example.

  In addition, the point which may be introduce | transduced into molecular structure 1 type (s) or 2 or more types other than an ethylene oxide unit, and the kind of functional group apply to (A) photopolymerizable monomer.

  Specific examples of the monofunctional photopolymerizable monomer in which no ethylene oxide unit is introduced into the molecular structure include, for example, 2-hydroxy-3-phenoxypropyl acrylate, methacrylate-modified silicone, perfluorooctylethyl acrylate, and 2-methacryloyllo. Monofunctional (meth) acrylates with no ethylene oxide units introduced into the molecular structure, such as ethyl acid phosphate, 2-acryloyloxyethyl acid phosphate, dimethylaminoethyl methacrylate, acryloyloxyethyl hexahydrophthalimide, nonylphenol propylene oxide modified acrylate, etc. It can be illustrated. These can be used alone or in combination of two or more.

  Examples of other components include various photopolymerizable oligomers. When it contains this, it can contribute to the improvement of the mechanical strength of hardened | cured material, etc.

  Specific examples of the photopolymerizable oligomer include, for example, epoxy such as bisphenol A acrylate, bisphenol F acrylate, bisphenol S acrylate, and phenol novolac acrylate from the viewpoints of curability, chemical resistance, heat resistance, adhesiveness, and the like. (Meth) acrylate: Urethane (meth) acrylate such as polyester urethane acrylate, polyether urethane acrylate, aromatic urethane acrylate, aliphatic urethane acrylate from the viewpoint of flexibility, abrasion resistance, adhesiveness, etc. Polyester (meth) acrylates such as PEA acrylate, PBA acrylate, PHA acrylate and carbonate acrylate from the viewpoint of low viscosity and physical property balance; Polyether (meth) acrylates such as pyrene glycol acrylate, polytetramethylene glycol acrylate, PEG acrylate, and caprolactone acrylate; polybutadiene (meth) acrylates such as butadiene acrylate from the viewpoint of water resistance and chemical resistance; viewpoints such as weather resistance Examples thereof include silicone (meth) acrylates such as silicone acrylate. These can be used alone or in combination of two or more. Moreover, these various oligomers are good in the range whose functional group number is about 1-15.

  Thus, this composition can use together photopolymerizable monomers and oligomers other than the said (A) component. When these are used, it is possible to adjust the hardness, amount of set, electrical resistance, mechanical properties, etc. of the resulting cured product by adjusting the type and amount of other components used. However, these contents occupied in the polymerization component contained in this composition are less than 40 weight% in total.

  Next, this composition contains the (B) photoinitiator as an essential component.

  The photopolymerization initiator is not particularly limited, and any photopolymerization initiator can be used as long as it can be normally used.

  Specific examples of the photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, 2-methylbenzoin, benzyl, benzyldimethylketal, diphenyl sulfide, and tetramethylthiuram monosulfide. , Diacetyl, eosin, thionine, mihira-ketone, anthracene, anthraquinone, acetophenone, α-hydroxyisobutylphenone, p-isopropylαhydroxyisobutylphenone, α · α 'dichloro-4-phenoxyacetophenone, 1-hydroxy-1-cyclohexylacetophenone 2,2-dimethoxy-2-phenylacetophenone, methylbenzoyl formate, 2-methyl-1- [4- (methylthio) phenyl] .2.morpholino-propene, thioxanthone , Benzophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 1-hydroxy-cyclohexyl-phenyl-ketone, benzophenone, 2-methyl-1- [4 -(Methylthio) phenyl] -2-monforinopropanone 1,2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone 1,2-hydroxy-2-methyl-1-phenyl- Propan-1-one, 2,4,6-trimethylbenzoyldiphenyl-phosphine oxide, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, Bis (cyclopentadienyl) -bis (2,6-difluoro-3- (pyryl) titanium), -Hydroxy-2-methyl-1-phenylpropan-1-one, bisacylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, (η5-2,4-cyclopentadien-1-yl ) [(1,2,3,4,5,6-η)-(1-methylethyl) benzene] -iron (1 +)-hexafluorophosphate (1-) and the like. These can be used alone or in combination of two or more.

  The lower limit of the content of the photopolymerization initiator is preferably 0.01 parts by weight or more, more preferably 0.1 parts by weight or more, and more preferably 100 parts by weight or more with respect to 100 parts by weight of the polymerization component contained in the composition. More preferably, it is 1 part by weight or more.

  On the other hand, the upper limit of the content of the photopolymerization initiator is preferably 50 parts by weight or less, more preferably 10 parts by weight or less with respect to 100 parts by weight of the polymerization component contained in the composition. .

  Next, this composition is good to further contain (C) an ionic conductive agent as a preferred additive component.

  The ionic conductive agent is not particularly limited, and any ionic conductive agent can be used as long as it can be used in the field of electrophotographic equipment.

Specific examples of the ionic conductive agent include, for example, quaternary ammonium perchlorate represented by chemical formula 12 (in the chemical formula 12, R ₁ , R ₂ , R ₃ , and R _{4 each} have 1 carbon atom) A borate represented by the formula (13): a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group, a decyl group, a phenyl group, or a xylyl group; In the chemical formula 13, R ₁ , R ₂ , R ₃ and R ₄ are alkyl groups having 1 to 18 carbon atoms, such as methyl group, ethyl group, propyl group, butyl group, hexyl group, phenyl group, xylyl group, etc. M ^{n +} is an alkali metal ion or alkaline earth metal ion, and represents lithium ion, sodium ion, potassium ion, calcium ion, etc.). These may be used alone or in combination.

(Chemical Formula 12)

(Chemical Formula 13)

  The lower limit value of the content of the ionic conductive agent is preferably 0.01 parts by weight or more, more preferably 0.1 parts by weight or more, and even more based on 100 parts by weight of the polymerization component contained in the composition. The amount is preferably 1 part by weight or more.

  On the other hand, the upper limit of the content of the ionic conductive agent is preferably 50 parts by weight or less, more preferably 10 parts by weight or less, with respect to 100 parts by weight of the polymerization component contained in the composition.

  In addition to the above, the present composition is a light stabilizer, a viscosity modifier, an anti-aging agent, a processing aid, a lubricant, a flame retardant, a plasticizer, and a foaming agent, as long as the object of the present invention is not impaired. In addition, one or more kinds of various additives such as a filler, a crosslinking agent, a crosslinking aid, a dispersant, an antifoaming agent, and a pigment may be contained.

  The composition described above has a viscosity (25 ° C.) of preferably 100,000 mPa · s or less, more preferably 10,000 mPa · s or less, from the viewpoint of good handleability. From the standpoint of excellent coating properties and the like, it is even more preferably 5000 mPa · s or less.

  In addition, a cured product obtained by curing the composition with ultraviolet rays is likely to contribute to, for example, reduction of noise generated during rotation and reduction of toner stress when used in a conductive roll for an electrophotographic apparatus. From this point of view, the durometer type A hardness is preferably in the range of 0 to 50, more preferably in the range of 0 to 40, and even more preferably in the range of 0 to 30.

  As a manufacturing method of this composition mentioned above, for example, (A) a photopolymerizable monomer which is an essential component, (B) a photopolymerization initiator, and (C) an ionic conductive agent or other optional components to be contained as necessary. Examples include a method in which the components are weighed so as to have a desired composition (however, the content of component (A) is 60% by weight or more), and these are mixed by a mixing means such as a stirrer or a sand mill. it can. In addition, you may perform a defoaming process etc. after mixing during mixing.

2. Electrophotographic apparatus member The electrophotographic apparatus member according to the present embodiment has a portion formed by curing the composition.

  Specific examples of the electrophotographic apparatus member include various conductive rolls such as a charging roll, a developing roll, a toner supply roll, and a transfer roll, and a conductive belt such as a transfer belt.

  In the conductive roll, one or two or more conductive layers are laminated on the outer periphery of the conductive shaft.

  Any conductive shaft material may be used as long as it has conductivity. In general, examples include solid bodies made of metal such as iron, stainless steel, and aluminum, and a cored bar made of a hollow body.

  As a specific layer structure of the conductive roll, a three-layer structure in which an intermediate layer such as a base layer and a resistance adjustment layer and a surface layer are sequentially stacked on the outer periphery of the conductive shaft, a base layer, and a surface layer are sequentially stacked 2 Examples of the layer structure can be given.

  Here, the conductive roll may have a conductive layer formed by curing the present composition at any position in the laminated structure. All the layers in the laminated structure may be conductive layers formed by curing the present composition. Moreover, when it has two or more electroconductive layers formed by hardening this composition, the composition of each electroconductive layer may be the same, or may each differ.

  The laminated thickness of the conductive roll is not particularly limited, but is preferably 0.1 from the viewpoint of reducing the diameter so as to be advantageous for downsizing of an image forming apparatus incorporating the conductive roll. -5 mm, more preferably 0.5-4 mm, and still more preferably 1-3 mm.

  The thickness of the base layer is usually about 0.1 to 3 mm. The thickness of the intermediate layer is usually about 0.1 to 1 mm. The thickness of the surface layer is usually about 1 μm to 20 μm.

  Specific examples of a material for forming a conductive layer other than the conductive layer according to the present composition include, for example, epichlorohydrin rubber, NBR, silicone rubber, EPDM, amide resin, cellulose resin, and acrylic resin. Resin, urethane resin, fluorine resin, etc., conductivity imparting agents such as electronic conducting agents and ionic conducting agents, and further, if necessary, one or two foaming agents, crosslinking agents, surface conditioning agents, plasticizers, etc. Examples include compositions added with more than one species. These may be used alone or in combination.

  The conductive layer obtained by curing the composition is coated with the composition by various coating methods such as dipping method, roll coating method, spray coating method, etc., and an ultraviolet irradiation device is applied to the applied composition. Thus, it can be formed by irradiating with a predetermined amount of ultraviolet rays for a predetermined time to be cured. The above application may be repeated once or twice or more.

  For example, when applying the present composition to the base layer, exemplify a method of immersing the conductive shaft in a storage tank storing the present composition, and then irradiating it with ultraviolet rays and curing it. Can do.

  In addition, for example, when the present composition is applied to an intermediate layer, a surface layer, etc., the present composition is stored in the same manner as described above for a roll body in which a conductive layer as a lower layer is formed on a conductive shaft. A method of immersing in a storage tank and pulling it up and irradiating it with ultraviolet rays, a method of applying this composition to the surface of the underlying conductive layer by a roll coating method, etc., and irradiating it with ultraviolet rays and curing it Can be illustrated.

  In addition, as a method of forming a conductive layer using another conductive layer material that does not depend on the present composition, although depending on the state of the material, a casting method, an extrusion method, a dipping method, a roll coating method, etc. Is mentioned.

  On the other hand, the conductive belt has one or two or more conductive layers on the surface of the substrate.

  In the conductive belt, either the base material or the conductive layer may be formed from a cured product of the present composition, and both the base material and the conductive layer are formed from the cured product of the present composition. May be.

  The base material and the conductive layer can be formed using a casting method, an extrusion method, a dipping method, a roll coating method, etc., depending on the state of the material.

  Hereinafter, the present invention will be described in detail using examples.

1. Preparation of conductive compositions according to Examples and Comparative Examples (Examples 1 to 23, Comparative Examples 1 to 8)
Various materials were weighed so that the blending ratios (units are parts by weight) shown in Tables 3 to 7 described later, and after stirring and mixing with a stirrer, they were allowed to stand at room temperature for 24 hours (for defoaming). By doing this, the ultraviolet curable conductive composition which concerns on Examples 1-23 and Comparative Examples 1-8 was prepared.

In addition, the various materials used at the time of preparation of these compositions are as follows.
(A) (EO-containing + monofunctional) photopolymerizable monomer (a1)
・ Phenoxyethylene oxide-modified acrylate (1) [manufactured by Toagosei Co., Ltd., “Aronix M102”]
-Phenoxyethylene oxide modified acrylate (2) [Shin Nakamura Chemical Co., Ltd., "NK ester AMP-60G"]
・ Methoxyethylene oxide modified acrylate [manufactured by Kyoeisha Chemical Co., Ltd., “Light acrylate 130A”]
-Nonylphenol ethylene oxide modified acrylate [manufactured by Kyoeisha Chemical Co., Ltd., "Light acrylate NP-4EA"]

(A2)
・ Polypropylene glycol (PPG) -urethane acrylate (1)
60.2 g of tolylene diisocyanate [Mitsui Chemicals Polyurethane Co., Ltd., “Cosmonate T100”] and 2hydroxyethyl acrylate [Osaka Organic Chemical Co., Ltd. “HEA”] 39.8 g were charged into a reaction vessel. The reaction was carried out at 80 ° C. for 8 hours to synthesize acrylate-added isocyanate.
Separately, 12.7 g of the obtained acrylate-added isocyanate and polypropylene glycol [containing 10% by weight of ethylene oxide unit, bifunctional, molecular weight 2000, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., “Hiflex D2000”] The reaction vessel was put in and reacted at 80 ° C. for 8 hours to synthesize monofunctional polypropylene glycol (PPG) -urethane acrylate (1).
In addition, when NCO% was measured after the synthesis, the remaining NCO was 0.5% or less, and it was confirmed that the synthesis reaction was completed.
Polyethylene glycol-urethane acrylate In the synthesis of the above polypropylene glycol (PPG) -urethane acrylate (1), polyethylene glycol (PEG) [containing 100% by weight of ethylene oxide unit, bifunctional, molecular weight 2000, manufactured by Sanyo Chemical Co., Ltd., Polyethylene glycol (PEG) -urethane acrylate was synthesized in the same manner except that PEG-2000 "] was used.

(EO-containing + multifunctional) photopolymerizable monomer / ethylene oxide modified diacrylate (bifunctional) [manufactured by Shin-Nakamura Chemical Co., Ltd., “NK Ester A-1000”]
・ Ethylene oxide modified glycerin triacrylate (trifunctional) [manufactured by Shin-Nakamura Chemical Co., Ltd., NK Ester A-GLY20EO]
・ Ethylene oxide-modified pentaerythritol tetraacrylate (tetrafunctional) [manufactured by Daicel UC Corporation, “Ebecryl 40”]

Photopolymerizable oligomer / carbonate diacrylate (bifunctional) [Shin Nakamura Chemical Co., Ltd., “NK Oligo UA-512”]
・ Butadiene diacrylate (bifunctional) [Shin Nakamura Chemical Co., Ltd., “NK Oligo UA511”]
Ester diacrylate (bifunctional) [Shin Nakamura Chemical Co., Ltd., "UA122P"]
Bisphenol A diacrylate (bifunctional) [Daicel UC Corporation, “Ebecryl 3700”]
・ Tetramethylene glycol diacrylate (trifunctional) [manufactured by Shin-Nakamura Chemical Co., Ltd., “UA160TM”]

(EO-free + monofunctional) photopolymerizable monomer, 2-hydroxy-3phenoxypropyl acrylate [manufactured by Kyoeisha Chemical Co., Ltd., "Epoxy ester M-600A"]
・ Polypropylene glycol (PPG) -urethane acrylate (2)
In the synthesis of the above-mentioned polypropylene glycol (PPG) -urethane acrylate (1), except that polypropylene glycol [bifunctional, molecular weight 2000, manufactured by Asahi Glass Urethane Co., Ltd., “Exenol 2020”] which does not contain an ethylene oxide unit was used Polypropylene glycol (PPG) -urethane acrylate (2) was synthesized.
-Methacrylate modified silicone [Shin-Etsu Chemical Co., Ltd., "X22-164B"]
Perfluorooctyl ethyl acrylate [manufactured by Kyoeisha Chemical Co., Ltd., “Light acrylate FA108”]

(B) Photopolymerization initiator [“Irgacure 189” manufactured by Ciba Specialty Chemicals Co., Ltd.]

(C) Ionic conductive agent, trimethyloctadecyl ammonium perchlorate

(Comparative Example 9)
100 parts by weight of conductive millable silicone rubber compound (Momentive Performance Materials Japan GK, “XE23-A4902”) and peroxide cross-linking agent (Momentive Performance Materials Japan GK, TC-8) A silicone rubber conductive composition according to Comparative Example 9 was prepared by kneading 1.5 parts by weight with a kneader.

(Comparative Example 10)
100 parts by weight of epichlorohydrin rubber (ECO) (manufactured by Daiso Corporation, “Epichromer CG102”), 1 part by weight of stearic acid (manufactured by Kao Corporation, “Lunac S-30”), and two types of zinc oxide ( 5 parts by weight of Mitsui Kinzoku Kogyo Co., Ltd., 3 parts by weight of an acid acceptor (manufactured by Kyowa Chemical Industry Co., Ltd., “DHT-4A”), 1.5 wt. Of powder sulfur (manufactured by Tsurumi Chemical Co., Ltd.) Parts, 1.5 parts by weight of a thiazole vulcanization accelerator (Ouchi Shinsei Chemical Co., Ltd., “Noxeller DM”), and a thialium vulcanization accelerator (Ouchi Shinsei Chemical Co., Ltd., “ A hydrin rubber-based conductive composition was prepared by kneading 0.5 parts by weight of Noxeller TS ") and 1 part by weight of trimethyloctadecyl ammonium perchlorate with a kneader.

2. Characteristics Evaluation of Conductive Compositions According to Examples and Comparative Examples Next, characteristics evaluation of each obtained conductive composition was performed as follows.

(viscosity)
The viscosity at 25 ° C. of the conductive compositions (liquid) according to Examples 1 to 23 and Comparative Examples 1 to 8 was measured with a B-type viscometer (manufactured by Tokimec Co., Ltd., “VISCOMETER DVL-B2”).

(hardness)
Sheets having a thickness of about 1 mm, a length of 100 mm, and a width of 100 mm were coated with the ultraviolet curable conductive compositions according to Examples 1 to 23 and Comparative Examples 1 to 8 on a glass plate by a bar coating method, and irradiated with ultraviolet rays. And a large test piece (a cylindrical cured product having a diameter of 29 mm and a thickness of 12.5 mm) defined in JIS K6262. At this time, the distance between the UV lamp (mercury lamp type) of the UV irradiation machine (“IUGRAPH Co., Ltd.“ UB031-2A / BM ”) and each coated composition was 200 mm, and the UV irradiation was performed for 30 seconds (integrated light quantity 120 mW / cm ² ).

  On the other hand, the rubber-based conductive compositions according to Comparative Example 9 and Comparative Example 10 were molded and cross-linked by pressing (Comparative Example 9 was 150 ° C. for 45 minutes, Comparative Example 10 was 160 ° C. for 30 minutes) and thickened. A sheet-like molded product having a length of about 1 mm, a length of 100 mm, and a width of 100 mm, and a large-sized test piece (a cylindrical molded product having a diameter of 29 mm and a thickness of 12.5 mm) defined in JIS K6262.

  Next, durometer type A hardness was measured for each obtained cylindrical cured product / molded product in accordance with JIS K6253.

(Compression set)
In order to examine the settling resistance, the compression set (compression rate 25%) after being held at 70 ° C. for 168 hours was measured in accordance with JIS K6262 using each of the above-mentioned columnar cured products and molded products.

(Volume resistivity and volume resistivity variation)
A 10 mm square electrode was formed on the surface of each sheet-like cured product / molded product, and the volume resistivity when 100 V was applied was measured. In addition, the electrical resistance value at 10 points was measured with an electrode having a diameter of 1 mm (Ω · cm), and the difference in electrical resistance between the maximum value (R _max ) and the minimum value (R _min ) was defined as (logR _max −logR _min ). This was determined as the volume resistance variation.

(Breaking strength, breaking elongation)
In accordance with JIS K6251, the breaking strength and breaking elongation of each cured product / molded product were measured using No. 2 dumbbell test pieces.

  Tables 3 to 7 collectively show the blending ratios and characteristic evaluation results of the conductive compositions according to Examples and Comparative Examples.

  Comparing Tables 3 to 7 reveals the following. That is, the molded article using the silicone rubber-based conductive composition according to Comparative Example 9 has a durometer type A hardness of 50 or less and a relatively low hardness. Moreover, the value of compression set (C.S.) is also low, and the settling resistance is also good. However, the volume resistance variation was large and the electric resistance was non-uniform.

  The molded article using the hydrin rubber-based conductive composition according to Comparative Example 10 had small variations in volume resistance and uniform electrical resistance. However, the durometer type A hardness exceeded 50 and was relatively high. Moreover, the value of the compression set (C.S.) was high, and the settling resistance was also poor.

  On the other hand, the hardened | cured material by the ultraviolet curable conductive composition which concerns on Examples 1-23 satisfy | fills the requirements prescribed | regulated by this invention. Therefore, it was confirmed that it had a low hardness and excellent resistance to settling and uniformity of electrical resistance compared to a molded product made of a silicone rubber-based or hydrin rubber-based conductive composition.

  Moreover, when Examples 1-23 which are the same ultraviolet curable conductive compositions and Comparative Examples 1-8 are compared, the following will be understood.

  That is, the compositions of Comparative Examples 1 to 3 are mainly composed of a monofunctional photopolymerizable monomer in which no ethylene oxide unit is introduced into the molecular structure. Therefore, the hardened | cured material of Comparative Examples 1-3 was high in electrical resistance compared with others, and it was difficult to aim at low resistance.

  The compositions of Comparative Examples 4 to 5 contain (a1) a monofunctional photopolymerizable monomer in which ethylene oxide units are introduced into the molecular structure. However, the proportion is less than the amount specified in the present application. Therefore, the hardened | cured material of Comparative Examples 4-5 was not able to achieve reduction in hardness. Moreover, the cured product of Comparative Example 4 also had high electrical resistance.

  The compositions of Comparative Examples 6 to 8 contain a photopolymerizable oligomer as a main component. For this reason, the viscosity increased rapidly, and the handleability deteriorated extremely. Moreover, the hardened | cured material of Comparative Examples 6-8 was extremely hardened, and the electrical resistance also became very high.

  On the other hand, the hardened | cured material of the composition of Examples 1-23 which satisfy | fills the requirements prescribed | regulated to this invention is compared with the hardened | cured material of the composition of Comparative Examples 1-8 which does not satisfy | fill the requirements prescribed | regulated to this invention. As a result, it was confirmed that the balance of low hardness, sag resistance, and uniformity of electrical resistance was excellent. In addition, the compositions of Examples 1 to 23 that satisfy the requirements defined in the present invention had a viscosity of 10,000 mPa · s or less and good handleability.

  Moreover, when Examples are compared, the following can be understood. That is, according to Examples 1-4, it turns out that there exists a tendency for hardened | cured material to become low hardness and low electrical resistance, so that an acrylic equivalent becomes large. However, it can be seen that the settling resistance and mechanical properties tend to deteriorate.

  However, according to Examples 5-6, it turns out that the mechanical characteristic of hardened | cured material can be improved by using the photopolymerizable monomer which has a urethane bond in molecular structure. It can also be seen that increasing the amount of ethylene oxide units introduced into the photopolymerizable monomer tends to lower the electrical resistance.

  In addition, according to Example 7, by using a monofunctional photopolymerizable monomer having a relatively large amount of ethylene oxide units, it is possible to secure an intermediate resistance region without adding (C) an ion conductive agent. I understand that there is.

  Moreover, according to Examples 8-11, it turns out that the settling resistance of hardened | cured material improves by further containing the polyfunctional photopolymerizable monomer in which the ethylene oxide unit is introduce | transduced in molecular structure.

  Moreover, according to Examples 12-13, it turns out that the mechanical characteristic of hardened | cured material can be improved by using the photopolymerizable monomer which has a urethane bond in molecular structure. It can also be seen that increasing the amount of ethylene oxide units introduced into the photopolymerizable monomer tends to lower the electrical resistance.

  Moreover, according to Examples 15-16, when a polyfunctional photopolymerizable monomer is contained, it turns out that it is easy to improve the settling resistance of hardened | cured material, so that there are many functional groups.

  Moreover, according to Examples 17-23, as a polymerization component in a composition, in addition to a specific amount of the component (A), a photopolymerizable oligomer or a monofunctional compound in which no ethylene oxide unit is introduced into the molecular structure. It turns out that a photopolymerizable monomer can be mixed.

  In this case, it can be seen that it is better to mix a silicone system from the viewpoint of reducing the hardness. From the standpoint of obtaining good resistance to sag, it can be seen that it is better to mix an ester. From the viewpoint of improving the mechanical strength, it can be seen that it is better to mix carbonates.

  That is, from these, in addition to the photopolymerizable monomer of component (A), by mixing photopolymerizable monomers and oligomers having various skeletons as necessary, the hardness of the cured product, resistance to settling, mechanical properties It turns out that intensity etc. can be adjusted according to aim.

4). Production of Development Roll, Charging Roll, and Transfer Belt for Electrophotographic Equipment Next, using the conductive compositions according to Examples 9, 10, 11, 12, and 13 and Comparative Examples 9 and 10 produced above, electrophotography A developing roll, a charging roll, and a transfer belt for equipment were prepared.

<Preparation of developing roll>
100 parts by weight of H-NBR (36% acrylonitrile, manufactured by LANXESS, “THEBAN B3850”), 0.5 parts by weight of stearic acid (manufactured by Kao Corporation, “Lunac S-30”), zinc Hana (ZnO) 5 parts by weight, dithiocarbamate vulcanization accelerator (Ouchi Shinsei Chemical Co., Ltd., “Noxeller BZ-P”) 1 part by weight, sulfenamide vulcanization accelerator (Ouchi) Shinsei Chemical Industry Co., Ltd., "Noxeller CZ-G" 2 parts by weight, carbon black (Electrochemical Industry Co., Ltd., "Denka Black HS100") 40 parts by weight, powder sulfur (Tsurumi Chemical Industry Co., Ltd.) 1) parts by weight and 800 parts by weight of MEK were blended and dispersed using a sand mill to prepare an intermediate layer material.

  100 parts by weight of a polyurethane elastomer (manufactured by Nippon Polyurethane Co., Ltd., “Nipporan 2304”), 20 parts by weight of isocyanate (manufactured by Dainippon Ink & Chemicals, Inc., “Bernock D750”), and 800 parts by weight of MEK are blended, A surface layer material was prepared by performing a dispersion treatment using a sand mill.

(Example 1G)
A core made of stainless steel (SUS304) having a diameter of 10 mm was immersed in a container filled with the ultraviolet curable conductive composition according to Example 9, and irradiated with ultraviolet rays immediately after being pulled up (irradiated for 30 seconds with a light amount of 120 mW / cm ² ) and the adhered composition was cured (dip coating method). The above operation was repeated 10 times to form a base layer having a thickness of 5 mm on the outer periphery of the cored bar.

  Next, the surface layer material was coated on the outer periphery of the base layer by a roll coating method, and heat-treated at 150 ° C. for 30 minutes to form a surface layer having a thickness of 6 μm.

  Thus, a two-layer developing roll according to Example 1G was produced.

(Example 2G)
Using the casting method, the silicone rubber-based conductive composition according to Comparative Example 9 was molded on the outer periphery of the cored bar, and heat-treated at 170 ° C. for 1 hour to form a base layer having a thickness of 5 mm.

Next, the base layer was immersed in a container filled with the ultraviolet curable conductive composition according to Example 11, and immediately after the base layer was pulled up, it was irradiated with ultraviolet light (irradiated for 30 seconds, light amount 120 mW / cm ² ) and adhered. The composition was cured (dip coating method). The above operation was repeated once to form an intermediate layer having a thickness of 10 μm on the outer periphery of the base layer.

  Next, the surface layer material was applied to the outer periphery of the intermediate layer by a roll coating method, and heat-treated at 150 ° C. for 30 minutes to form a surface layer having a thickness of 6 μm.

  Thus, a three-layer developing roll according to Example 2G was produced.

(Comparative Example 1G)
Using the casting method, the silicone rubber-based conductive composition according to Comparative Example 9 was molded on the outer periphery of the cored bar, and heat-treated at 170 ° C. for 1 hour to form a base layer having a thickness of 5 mm.

  Next, the intermediate layer material was applied to the outer periphery of the base layer by a roll coating method, and heat-treated at 150 ° C. for 30 minutes, thereby forming an intermediate layer having a thickness of 10 μm.

  Next, the surface layer material was applied to the outer periphery of the intermediate layer by a roll coating method, and heat-treated at 150 ° C. for 30 minutes to form a surface layer having a thickness of 6 μm.

  Thus, a three-layer developing roll according to Comparative Example 1G was produced.

<Preparation of charging roll>
313 parts by weight of a fluorine-modified acrylic binder (Dainippon Ink & Chemicals, “Defenser TR230K”), 50 parts by weight of a fluororesin (manufactured by Atofina Japan, “Kyner 7201”), and conductive titanium oxide An acrylic surface layer material was prepared by blending 100 parts by weight (Ishihara Techno Co., Ltd., “Typaque ET300W”) and 200 parts by weight of MEK, and dispersing the mixture using a sand mill.

Example 1T
A core metal having a diameter of 6 mm was immersed in a container filled with the ultraviolet curable conductive composition according to Example 10, and immediately after being pulled up, irradiated with ultraviolet rays (irradiated for 30 seconds, light amount 120 mW / cm ² ) and adhered. The resulting composition was cured (dip coating method). The above operation was repeated 10 times to form a 1.75 mm thick base layer on the outer periphery of the cored bar.

  Next, the acrylic surface layer material was applied to the outer periphery of the base layer by a roll coating method, and heat-treated at 120 ° C. for 30 minutes to form a surface layer having a thickness of 6 μm.

  Thus, a two-layered charging roll according to Example 1T was produced.

Example 2T
Using the extrusion method, the hydrin rubber-based conductive composition according to Comparative Example 10 was extruded on the outer periphery of the metal core, and heat-treated at 180 ° C. for 1 hour to form a base layer having a thickness of 1.74 mm.

Next, the base layer was immersed in a container filled with the ultraviolet curable conductive composition according to Example 12, and immediately after being pulled up, irradiated with ultraviolet rays (irradiated for 30 seconds, light amount 120 mW / cm ² ) and adhered. The composition was cured (dip coating method). The above operation was performed once to form an intermediate layer having a thickness of 100 μm on the outer periphery of the base layer.

  Subsequently, the acrylic surface layer material was applied to the outer periphery of the intermediate layer by a roll coating method, and a heat treatment was performed at 120 ° C. for 30 minutes to form a surface layer having a thickness of 6 μm.

  Thus, a charging roll having a three-layer structure according to Example 2T was produced.

(Comparative Example 1T)
A base layer having a thickness of 1.75 mm was formed by extruding the hydrin rubber-based conductive composition according to Comparative Example 10 on the outer periphery of the core metal by an extrusion method, followed by heat treatment at 180 ° C. for 1 hour.

  Next, the acrylic surface layer material was applied to the outer periphery of the base layer by a roll coating method, and heat-treated at 120 ° C. for 30 minutes to form a surface layer having a thickness of 6 μm.

  Thus, a two-layered charging roll according to Comparative Example 1G was produced.

<Preparation of transfer belt>
100 parts by weight of fluororesin (manufactured by Daikin Industries, Ltd., “Neofuron VT100”), 10 parts by weight of carbon black (manufactured by Denki Kagaku Kogyo Co., Ltd., “Denka Black HS100”), and 200 parts by weight of acetone are blended. The base layer material was prepared by a dispersion treatment using a ring mill.

  100 parts by weight of an acrylic silicone binder (manufactured by Toagosei Co., Ltd., “Cymac US350”), 10 parts by weight of carbon black (manufactured by Denki Kagaku Kogyo Co., Ltd., “Denka Black HS100”), and 400 parts by weight of toluene And surface layer material was prepared by carrying out dispersion processing using a ring mill.

(Example 1B)
The cylindrical mold was dipped in a container filled with the base material and pulled up, and then the adhered composition was dried at 120 ° C. for 30 minutes (dip coating method). The above operation was repeated twice to form a 150 μm thick base layer.

Next, the base layer was immersed in a container filled with the ultraviolet curable conductive composition according to Example 13, and immediately after the substrate was pulled up, it was irradiated with ultraviolet rays (irradiated for 30 seconds, light amount 120 mW / cm ² ) and adhered. The composition was cured (dip coating method). The above operation was performed once to form a surface layer having a thickness of 100 μm on the surface of the base layer.

  Thus, a transfer belt having a two-layer structure according to Example 1B was produced.

(Comparative Example 1B)
A cylindrical mold was dipped in the container filled with the base material and pulled up, and then the adhered composition was dried (dip coating method). The above operation was repeated twice to form a 150 μm thick base layer.

  Next, the base layer was immersed in the container filled with the surface layer material and pulled up, and then the adhered composition was dried with hot air at 120 ° C. for 30 minutes (dip coating method). The above operation was performed once to form a surface layer having a thickness of 10 μm on the surface of the base layer.

  Thus, a transfer belt having a two-layer structure according to Comparative Example 1B was produced.

5. Evaluation of developing roll, charging roll, transfer belt <Evaluation of developing roll and charging roll>
(Roll surface hardness)
The hardness of each roll surface was measured using “Asker Rubber Hardness Tester Type A” manufactured by Kobunshi Keiki Co., Ltd.

(Roll resistance)
The metal drum and each roll were brought into line contact, each roll was rotated at 200 rpm, and the electrical resistance in a state where 1000 V was applied was measured to obtain a roll resistance.

(Slip amount)
A metal plate was pressed against the surface of each roll, deformed at a constant displacement of 50 μm, held at 50 ° C. for 168 hours, and the amount of settling after release was measured.

(Image evaluation)
Each roll is incorporated in the cartridge of a color laser printer (Developing Roll / Canon, “LBP-2510”, Charging Roll / Ricoh, “IPSIO CX-3000”), and a solid image in the initial state Was output. About the obtained image, the presence or absence of the image dark unevenness was confirmed visually. A case where there was no unevenness in image density was rated as “good”, and a case where unevenness in image density occurred was rated as “bad”.

(Evaluation of sticking out image)
Each roll after measuring the amount of sag was incorporated into the cartridge, a solid image was output, and the presence or absence of stagnation was visually evaluated. The case where no stalege was present was evaluated as “good”, and the case where stalege was generated was evaluated as “bad”.

(Durability evaluation)
Each roll was incorporated into a cartridge of a commercially available color laser printer, and after 10000 halftone images were output in a low-temperature and low-humidity environment of 15 ° C. × 10% RH, a solid image was output. About the obtained image, the presence or absence of the image dark unevenness was confirmed visually. A case where there was no unevenness in image density was rated as “good”, and a case where unevenness in image density occurred was rated as “bad”.

<Evaluation of transfer belt>
(Belt surface hardness)
The hardness of each belt surface was measured using “Micro rubber hardness meter MD-1 type A” manufactured by Kobunshi Keiki Co., Ltd.

(Belt resistance)
In accordance with JIS K6271 double ring electrode method, the electrical resistance was measured to obtain a belt resistance.

(Image evaluation)
Each belt was incorporated in a cartridge of a commercially available color laser printer, a solid image was output, and transfer defects due to abnormal discharge were visually confirmed. The case where the transfer failure due to the abnormal discharge occurred was evaluated as “good”, and the case where the transfer failure due to the abnormal discharge occurred was determined as “bad”.

(Durability evaluation)
Each belt was incorporated into a cartridge of a commercially available color laser printer (“Imagio MPC2500” manufactured by Ricoh Co., Ltd.), and 10,000 halftone images were taken out in a low temperature and low humidity environment of 15 ° C. × 10% RH. Later, a solid image was output. About the obtained image, the presence or absence of the image dark unevenness was confirmed visually. A case where there was no unevenness in image density was rated as “good”, and a case where unevenness in image density occurred was rated as “bad”.

  Tables 8 to 10 show the evaluation results of the developing roll, the charging roll, and the transfer belt according to Examples and Comparative Examples.

  According to Tables 8 to 10, the developing roll, the charging roll, and the transfer belt using the conductive composition according to the examples are all excellent in low hardness, set resistance, and uniformity in electrical resistance. It was confirmed that both can contribute to high image quality.

  The embodiments and examples of the present invention have been described above, but the present invention is not limited to the above-described embodiments and examples, and various modifications can be made without departing from the spirit of the present invention. is there.

Claims (10)

(A) One or more photopolymerizable monomers selected from the following (a1) and (a2);
(A1) Monofunctional first photopolymerizable monomer having an ethylene oxide unit introduced into the molecular structure (a2) A monofunctional first photopolymerizable monomer having an ethylene oxide unit introduced into the molecular structure and having a urethane bond 2 photopolymerizable monomer (B) containing a photopolymerization initiator,
Further containing a polyfunctional photopolymerizable monomer having an ethylene oxide unit introduced into the molecular structure;
Content of the said (A) component which occupies for the polymerization component contained in the said composition is 60 weight% or more, The ultraviolet curable conductive composition characterized by the above-mentioned. The ultraviolet curable conductive composition according to claim 1, further comprising (C) an ion conductive agent.   The ultraviolet curable conductive composition according to claim 1 or 2, wherein the second photopolymerizable monomer has the ethylene oxide unit introduced through the urethane bond.   4. The ultraviolet curable conductive composition according to claim 1, wherein the first photopolymerizable monomer and the second photopolymerizable monomer are monofunctional (meth) acrylates. 5. 5. The ultraviolet curable conductive composition according to claim 1, wherein the polyfunctional photopolymerizable monomer has a molecular weight in the range of 200 to 20,000. 6. The ultraviolet curable conductive composition according to claim 1, wherein the polyfunctional photopolymerizable monomer is a polyfunctional (meth) acrylate. The ultraviolet curable conductive composition according to any one of claims 1 to 6 , wherein the durometer type A hardness after curing of the composition is in the range of 0 to 50. An electrophotographic apparatus member having a portion formed by curing the ultraviolet curable conductive composition according to claim 1 . A conductive roll for an electrophotographic apparatus, having a layer formed by curing the ultraviolet curable conductive composition according to claim 1 . A conductive belt for an electrophotographic apparatus having a layer formed by curing the ultraviolet curable conductive composition according to claim 1 .