JP2007322601A - Conductive roller and image forming apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conductive roller which does not require a drying step, and is manufactured in a short time, whose variance in characteristic is small, which is excellent in the slidability of its surface and is manufactured even under atmosphere. <P>SOLUTION: The conductive roller is equipped with cured substance composed by cationically polymerizing a material mixture containing a cationic polymerized compound, at least a kind of compound selected from a group composed of a fluorine containing compound and a silicon containing compound, and an optical cationic polymerization initiator by UV irradiation. It is desirable to use a compound having an oxirane ring and vinyl ether as the cationic polymerized compound. It does not matter whether the fluorine containing compound and the silicon containing compound have cationic polymerizable property or non-cationic polymerizable property. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a conductive roller and an image forming apparatus using the conductive roller, and in particular, does not require a drying step, can be manufactured in a short time, has small variations in characteristics, and has excellent surface slipperiness. Relates to a conductive roller that can be manufactured even in the atmosphere, and an image forming apparatus including the conductive roller as a developing roller, a charging roller, or the like.

  In an electrophotographic image forming apparatus such as a copying machine or a printer, as a developing method for visualizing a latent image by supplying toner to a photosensitive drum or the like holding a latent image and attaching the toner to the latent image on the photosensitive drum. A pressure development method is known. In the pressure development method, for example, after the photosensitive drum is charged to a constant potential, an electrostatic latent image is formed on the photosensitive drum by an exposure machine, and further, a developing roller carrying toner is placed on the electrostatic latent image. Development is performed by bringing the toner into contact with the latent image on the photosensitive drum in contact with the held photosensitive drum.

  In addition, the corona discharge method has been conventionally used for charging the photosensitive drum. However, in the corona discharge method, it is necessary to apply a high voltage of 6 to 10 kV, which is not preferable from the viewpoint of ensuring the safety of the apparatus. Furthermore, since harmful substances such as ozone are generated during corona discharge, it is not preferable from the viewpoint of environment. On the other hand, a contact charging method has been proposed in which a charging roller is brought into contact with the photosensitive drum and a voltage is applied between the photosensitive drum and the charging roller to charge the photosensitive drum.

  Since the developing roller and the charging roller must be rotated while being securely held in contact with the photosensitive drum, silicone rubber, acrylonitrile-butadiene rubber (NBR) is provided on the outer periphery of a shaft made of a highly conductive material such as metal. ), Ethylene-propylene-diene rubber (EPDM), epichlorohydrin rubber (ECO), an elastic layer made of a conductive elastic body in which carbon black or metal powder is dispersed in an elastomer such as polyurethane, or a foamed body obtained by foaming these. The structure is formed. In some cases, a resin coating layer is further formed on the surface of the elastic layer for the purpose of controlling the chargeability and adhesion to the toner and preventing contamination of the photosensitive drum by the elastic layer.

  In addition to the developing roller and the charging roller, a toner supply roller for supplying toner to the developing roller, a transfer roller for transferring the toner attached to the latent image on the photosensitive drum to a recording medium, and the photosensitive drum after transfer A conductive roller having a structure in which an elastic layer is formed on the outer periphery of the shaft as described above and a coating layer is further formed on the surface of the elastic layer is used for a cleaning roller for removing toner remaining on the surface. It has been.

  By the way, conventionally, the coating layer of the conductive roller is prepared by dipping the roller body composed of the shaft and the elastic layer into a solvent-based or water-based coating liquid, or spraying the coating liquid on the roller body. It is formed by drying and curing with heat or hot air. However, in this case, since a long drying time is required, a long drying line is required for mass production. Moreover, since the heat curing of the coating liquid requires a long curing time, there is a problem in productivity. In addition, the coating layer is required to have subtle electrical conductivity and surface condition due to its functions, but the quality distribution of the coating layer is greatly affected by variations in temperature distribution and air volume in the drying line. There was also a problem.

  On the other hand, JP 2002-310136 A (Patent Document 1) discloses radical generating photopolymerization as a technique for forming a coating layer with a stable quality in a short time without requiring a long drying line. There has been proposed a technique in which an ultraviolet curable coating liquid containing an initiator is applied to the outer surface of a roller body and cured to form a coating layer.

JP 2002-310136 A

  However, as a result of investigations by the present inventors, the coating layer material described in JP-A No. 2002-310136 has a curing reaction that is inhibited by oxygen. There is a problem that the layer material is not cured or only partially cured, and the adhesiveness of the coating layer surface is increased. Therefore, it is necessary to perform the curing in an inert gas atmosphere such as nitrogen. In this case, there are problems such as an increase in manufacturing cost and a complicated manufacturing process.

  Also, conductive rollers with a coating layer formed by ultraviolet irradiation on the surface have high frictional resistance on the roller surface, so that depending on the conditions of use, the roller surface may wear, the coating layer may peel off, or toner filming There was a problem that occurred. For this reason, there has been a problem that when an image forming apparatus incorporating such a conductive roller is used for a long time, an image defect is likely to occur.

  Therefore, the object of the present invention is to solve the above-mentioned problems of the prior art, and can be manufactured in a short time without the need for a drying process, with small variations in characteristics, excellent surface slipperiness, and manufacture even in the atmosphere. It is an object of the present invention to provide a conductive roller that can be used. Another object of the present invention is to provide an image forming apparatus provided with such a conductive roller and capable of stably forming a good image.

  As a result of diligent studies to achieve the above object, the present inventors used a cation-generating photopolymerization initiator instead of a radical-generating photopolymerization initiator as a photopolymerization initiator, and used it as a resin raw material. By using a cationically polymerizable compound and further using a fluorine-containing compound and / or a silicon-containing compound, a cured product can be formed in a short time by irradiation with ultraviolet rays even in the atmosphere, and the cured product has excellent surface slipperiness. As a result, the present invention has been completed.

  That is, the conductive roller of the present invention is prepared by cationic polymerization of a raw material mixture containing a cationically polymerizable compound, at least one selected from the group consisting of a fluorine-containing compound and a silicon-containing compound, and a photocationic polymerization initiator by ultraviolet irradiation. It is characterized by comprising a cured product.

  In the conductive roller of the present invention, the cationic polymerizable compound is preferably a compound having an oxirane ring and vinyl ether. Here, as a compound which has the said oxirane ring, an epoxy compound and an oxetane compound are preferable.

  In a preferred example of the conductive roller of the present invention, the raw material mixture contains at least one selected from the group consisting of a cationic polymerizable fluorine-containing compound and a cationic polymerizable silicon-containing compound.

  In another preferred embodiment of the conductive roller of the present invention, the raw material mixture contains at least one selected from the group consisting of a non-cationically polymerizable fluorine-containing compound and a non-cationically polymerizable silicon-containing compound.

  In another preferred embodiment of the conductive roller of the present invention, the raw material mixture is at least one selected from the group consisting of a cationic polymerizable fluorine-containing compound and a cationic polymerizable silicon-containing compound, and a non-cation polymerizable And at least one selected from the group consisting of fluorine-containing compounds and non-cationically polymerizable silicon-containing compounds.

  The conductive roller of the present invention preferably further includes a shaft member, and a layer made of the cured product is disposed on the outer periphery of the shaft member.

  The conductive roller of the present invention includes a shaft member, an elastic layer disposed on the outer side in the radial direction of the shaft member, and a coating layer disposed on the outer side in the radial direction of the elastic layer. It is also preferred that the layer consists of the cured product.

  Here, the shaft member is preferably a metal and resin solid body, a metal and resin hollow body, and a composite in which a resin base material is disposed on the outer periphery of the metal solid body.

  An image forming apparatus according to the present invention includes the above-described conductive roller.

  According to the present invention, there is provided a cured product obtained by cationic polymerization of a raw material mixture containing a cation-generating photopolymerization initiator, a cationic polymerizable compound, a fluorine-containing compound and / or a silicon-containing compound by ultraviolet irradiation. Thus, it is possible to provide a conductive roller that can be manufactured in a short time without requiring a drying step, has small variations in characteristics, has excellent surface slipperiness, and can be manufactured even in the atmosphere. Further, it is possible to provide an image forming apparatus that can stably form a good image using such a conductive roller.

<Conductive roller>
Hereinafter, the conductive roller of the present invention will be described in detail with reference to the drawings. 1 is a cross-sectional view of an example of the conductive roller of the present invention, FIG. 2 is a cross-sectional view of another example of the conductive roller of the present invention, and FIG. 3 is a shaft of the conductive roller of the present invention. FIG. 4 is a cross-sectional view of an example of a metal or resin hollow body that can be used as a member. FIG. 4 shows a resin base material disposed on the outer periphery of a metal solid body that can be used as a shaft member in the conductive roller of the present invention. It is sectional drawing of an example of the composite_body | complex formed.

  The conductive roller of the present invention is obtained by cationically polymerizing a raw material mixture containing a cationically polymerizable compound, at least one selected from the group consisting of a fluorine-containing compound and a silicon-containing compound, and a photocationic polymerization initiator by ultraviolet irradiation. It comprises the hardened | cured material which becomes. In the raw material mixture, the cationic photopolymerization initiator can generate cations upon irradiation with ultraviolet rays. In the raw material mixture, the cationically polymerizable compound can be polymerized by cations generated from the photocationic polymerization initiator. Here, since generation of cations by ultraviolet irradiation and initiation of polymerization by the generated cations are not inhibited by oxygen, the curing of the raw material mixture proceeds sufficiently even in the air. Therefore, the conductive roller of the present invention can be manufactured even in the atmosphere. Further, the cured product does not need to be dried and has a short curing time, so that it can be produced in a short time and has little variation in characteristics.

  Furthermore, since the raw material mixture contains a fluorine-containing compound and / or a silicon-containing compound, the cured product has low surface energy and excellent surface slipperiness. Excellent. Further, the cured product is excellent in toner releasability and can reliably prevent toner filming.

The cationic photopolymerization initiator used in the raw material mixture has a function of generating a cation by ultraviolet irradiation and initiating polymerization of the cationically polymerizable compound. Examples of the photocationic polymerization initiator include iodonium salts, sulfonium salts, phosphonium salts, ferrocene and the like. Examples of the iodonium salt include 4-methylphenyl-4- (2-methylpropyl) phenyliodonium hexafluorophosphate, 4-methylphenyl-4- (2-methylpropyl) phenyliodonium hexafluoroantimonate, 4-methylphenyl- 4- (2-methylpropyl) phenyliodonium tetrafluoroborate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium hexafluorophosphate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium hexafluoro Antimonate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium tetrafluoroborate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, diphenyliodoniumtetraf Examples of the sulfonium salt include triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrafluoroborate, bis [4- (diphenylsulfonio) phenyl] sulfide bishexafluorophosphate. Bis [4- (diphenylsulfonio) phenyl] sulfide bishexafluoroantimonate, bis [4- (diphenylsulfonio) phenyl] sulfide bistetrafluoroborate, and the like. Examples of the phosphonium salt include tetraphenylphosphonium hexa Fluorophosphate, tetraphenylphosphonium hexafluoroantimonate, tetraphenylphosphonium tetrafluoroborate, etc. The Sen, eta ⁵ - cyclopentadienyl eta ⁵ - cumenyl - iron (II) hexafluorophosphate, eta ⁵ - cyclopentadienyl eta ⁵ - cumenyl - iron (II) hexafluoroantimonate, eta ⁵ - And cyclopentadienyl-η ⁵ -cumenyl-iron (II) tetrafluoroborate. These photocationic polymerization initiators may be used alone or in a combination of two or more.

  As the cationically polymerizable compound used in the raw material mixture, a compound having an oxirane ring and vinyl ether are preferable. Here, as a compound which has an oxirane ring, an epoxy compound and an oxetane compound are preferable. Examples of the vinyl ether include methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, t-butyl vinyl ether, triethylene glycol divinyl ether, and the like. These cationically polymerizable compounds may be used alone or in combination of two or more.

  The epoxy compound that can be used in the raw material mixture has one or more, preferably two or more epoxy groups. Examples of the epoxy compound include (3,4-epoxycyclohexyl) methyl-3 ′, 4′-epoxycyclohexylcarboxylate, ε-caprolactone-modified (3,4-epoxycyclohexyl) methyl-3 ′, 4′-epoxycyclohexylcarboxyl. In addition to alicyclic epoxy compounds such as chelates, 1,2-epoxy-4-vinylcyclohexane, 1,2: 8,9-diepoxy limonene, dodecyl glycidyl ether, tridecyl glycidyl ether, polyethylene glycol diglycidyl ether, polypropylene Glycol diglycidyl ether, neopentyl glycol diglycidyl ether, trimethylolpropane triglycidyl ether, tripropylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl Ether, glycerin triglycidyl ether, bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, epoxy novolac resin, cresol novolac epoxy resin, epoxidized polybutadiene, etc. It is done. Among these, alicyclic epoxy compounds are preferable. These epoxy compounds may be used individually by 1 type, and may mix and use 2 or more types.

  The oxetane compound (that is, a 4-membered cyclic ether compound) that can be used in the raw material mixture has one or more, preferably two or more oxetane rings. When the said raw material mixture contains an oxetane compound, the speed | rate of the hardening reaction by ultraviolet irradiation can be improved. Examples of the oxetane compound include 3-ethyl-3-hydroxymethyloxetane, 3-ethyl-3-phenoxymethyloxetane, 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane, and 3-ethyl-3-cyclohexyl. Oxymethyl oxetane, bis (3-ethyl-3-oxetanylmethyl) ether, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene (ie, xylylene oxetane), and the like Of these, bis (3-ethyl-3-oxetanylmethyl) ether and 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene are preferable. These oxetane compounds may be used individually by 1 type, and 2 or more types may be mixed and used for them.

  The blending amount of the photocationic polymerization initiator in the raw material mixture is preferably in the range of 0.01 to 5 parts by mass with respect to 100 parts by mass of the cationically polymerizable compound. When the blending amount of the cationic photopolymerization initiator is less than 0.01 parts by mass, the raw material mixture may not be sufficiently cured by ultraviolet irradiation. On the other hand, when it exceeds 5 parts by mass, the proportion of the expensive cationic photopolymerization initiator is too high. This increases the cost of blending the raw material mixture.

  The fluorine-containing compound and silicon-containing compound used in the raw material mixture may be cationically polymerizable or non-cationically polymerizable, and in any case, the resulting cured product has a small surface energy, Since the surface slipperiness is excellent, the toner releasability is excellent, and the occurrence of toner filming can be prevented. In addition, when using a cationically polymerizable fluorine-containing compound or a silicon-containing compound in the raw material mixture, there is no need to use a separate cationically polymerizable compound, that is, a cationically polymerizable fluorine-containing compound and a cationically polymerizable silicon. A conductive roller provided with a cured product obtained by cationic polymerization of a raw material mixture containing at least one selected from the group consisting of contained compounds and a cationic photopolymerization initiator by ultraviolet irradiation is also an example of the conductive roller of the present invention. is there. In addition, non-cationically polymerizable fluorine-containing compounds and silicon-containing compounds tend to be unevenly distributed on the surface side because they have lower surface energy than compounds that do not contain fluorine and silicon. The releasability of is improved. Furthermore, even if the content of the non-cationically polymerizable fluorine and / or silicon-containing compound in the raw material mixture is reduced, the fluorine and / or silicon-containing compound is unevenly distributed on the surface side. The moldability can be sufficiently maintained, and the content of expensive fluorine and / or silicon-containing compounds can be reduced. The fluorine content in the fluorine-containing compound is preferably in the range of 0.05 to 76% by mass, more preferably in the range of 0.08 to 76% by mass, and particularly preferably in the range of 0.1 to 76% by mass. The silicon content in the silicon-containing compound is preferably in the range of 0.01 to 40% by mass, more preferably in the range of 0.05 to 35% by mass, and particularly preferably in the range of 0.1 to 30% by mass.

  Examples of the cationic polymerizable fluorine-containing compound include 3-perfluorobutyl-1,2-epoxypropane, 3-perfluoropentyl-1,2-epoxypropane, 3-perfluorohexyl-1,2-epoxypropane, Such as 3-perfluoroheptyl-1,2-epoxypropane, 3-perfluorooctyl-1,2-epoxypropane, 1,4-bis (2 ′, 3′-epoxypropyl) -perfluoro-n-butane, etc. Fluorine-containing epoxy compounds; 2,2,3,3,4-pentafluorooxetane, 2,2,3,3,4,4-hexafluorooxetane, 3-methyl-3- [1,1,2,3 , 3,3-Hexafluoropropyloxymethyl] oxetane, 3-ethyl-3- [1,1,2,3,3,3-hexafluoropropyloxymethyl] oxetane, 3-methyl-3- [1,1 , 2,2,3,3,3-heptafluoropropyloxymethyl] oxy Cetane, 3-ethyl-3- [1,1,2,2,3,3,3-heptafluoropropyloxymethyl] oxetane, 3-methyl-3-[{1- (1-trifluoromethyl-2, 2,2-trifluoroethyl) -1,2,2,3,3,3-hexafluoropropyl} oxymethyl] oxetane, 3-ethyl-3-[{1- (1-trifluoromethyl-2,2 , 2-trifluoroethyl) -1,2,2,3,3,3-hexafluoropropyl} oxymethyl] oxetane, 3-methyl-3- [1,3,4,4,4-pentafluoro-1 , 3-Bis (trifluoromethyl) -2- (heptafluoroisopropyl) butyloxymethyl] oxetane, 3-ethyl-3- [1,3,4,4,4-pentafluoro-1,3-bis (tri Fluoromethyl) -2- (heptafluoroisopropyl) butyloxymethyl] oxetane, 3-methyl-3- [1- (1,1,2,2,2-pentafluoroethyl) -2-trifluoro Romethyl-1,2,3,3,3-pentafluoropropyloxymethyl] oxetane, 3-ethyl-3- [1- (1,1,2,2,2-pentafluoroethyl) -2-trifluoromethyl -1,2,3,3,3-pentafluoropropyloxymethyl] oxetane, 3-methyl-3- [1,2,3,4,4,4-hexafluoro-1,3-bis (trifluoromethyl) ) -2- (Heptafluoroisopropyl) butyloxymethyl] oxetane, 3-ethyl-3- [1,2,3,4,4,4-hexafluoro-1,3-bis (trifluoromethyl) -2- (Heptafluoroisopropyl) butyloxymethyl] oxetane, 3-methyl-3- [1,2,3-trifluoroethenyloxymethyl] oxetane, 3-ethyl-3- [1,2,3-trifluoroethenyloxymethyl ] Oxetane, 3-methyl-3- [1-pentafluoroethyl-2,2-bis (trifluoromethyl) ester Nyloxymethyl] oxetane, 3-ethyl-3- [1-pentafluoroethyl-2,2-bis (trifluoromethyl) ethenyloxymethyl] oxetane, 3-methyl-3- [1,2-difluoro-2 -Trifluoromethylethenyloxymethyl] oxetane, 3-ethyl-3- [1,2-difluoro-2-trifluoromethylethenyloxymethyl] oxetane, 3-methyl-3- [1-trifluoromethyl-2 , 2-Bis (heptafluoroisopropyl) ethenyloxymethyl] oxetane, 3-ethyl-3- [1-trifluoromethyl-2,2-bis (heptafluoroisopropyl) ethenyloxymethyl] oxetane, 3-methyl- 3- [2-Fluoro-1,2-bis (trifluoromethyl) ethenyloxymethyl] oxetane, 3-ethyl-3- [2-fluoro-1,2-bis (trifluoromethyl) ethenyloxymethyl] Oxetane And fluorine-containing oxetane compounds.

Examples of the cation polymerizable silicon-containing compound include both-terminal glycidyl ether-type silicones, both-end alicyclic epoxy-type silicones, and these silicones include, for example, the following formula (I):
_{A-Si (CH 3) 2} -O- [Si (CH 3) 2 -O] n -Si (CH 3) 2 -A ··· (I)
[Wherein, A is an alicyclic epoxy group such as a glycidyl group or a (3,4-epoxycyclohexyl) methyl group, and n is the number of repeating units]. Specifically, examples of the both-terminal glycidyl ether type silicone include product names “X-22-163A”, product names “X-22-163B”, and product names “X-22-163C” manufactured by Shin-Etsu Silicone Co., Ltd. Examples of the both-terminal alicyclic epoxy type silicone include “X-22-169AS” manufactured by Shin-Etsu Silicone Co., Ltd.

  Examples of the non-cationically polymerizable fluorine-containing compound include compounds derived from fluoroolefins, fluoro (meth) acrylates, fluorine-containing (meth) acrylate resins, fluorine-containing olefin resins, and the like.

  Fluoroolefins used in the compounds derived from the above-mentioned fluoroolefins include vinyl fluoride, vinylidene fluoride, trifluoroethylene, tetrafluoroethylene, hexafluoropropene, (perfluorobutyl) ethylene, (perfluorohexyl) Ethylene, (perfluorooctyl) ethylene, (perfluorodecyl) ethylene, chlorotrifluoroethylene, 1-methoxy- (perfluoro-2-methyl-1-propene), 1,4-divinyloctafluorobutane, 1,6 -Divinyldodecafluorohexane, 1,8-divinylhexadecafluorooctane and the like.

  Examples of the fluoro (meth) acrylates include 2,2,2-trifluoroethyl acrylate, 2,2,3,3,3-pentafluoropropyl acrylate, 2- (perfluorobutyl) ethyl acrylate, 3- (par Fluorobutyl) -2-hydroxypropyl acrylate, 2- (perfluorohexyl) ethyl acrylate, 3- (perfluorohexyl) -2-hydroxypropyl acrylate, 2- (perfluorooctyl) ethyl acrylate, 3- (perfluorooctyl) ) -2-hydroxypropyl acrylate, 2- (perfluorodecyl) ethyl acrylate, 2- (perfluoro-3-methylbutyl) ethyl acrylate, 3- (perfluoro-3-methylbutyl) -2-hydroxypropyl acrylate, 2- (Perfluoro-5-methylhexyl) ethyl acrylate, 3- (perfluoro- -Methylhexyl) -2-hydroxypropyl acrylate, 2- (perfluoro-7-methyloctyl) ethyl acrylate, 3- (perfluoro-7-methyloctyl) -2-hydroxypropyl acrylate, 1H, 1H, 3H-tetra Fluoropropyl acrylate, 1H, 1H, 5H-octafluoropentyl acrylate, 1H, 1H, 7H-dodecafluoroheptyl acrylate, 1H, 1H, 9H-hexadecafluorononyl acrylate, 1H-1- (trifluoromethyl) trifluoroethyl Acrylate, 1H, 1H, 3H-hexafluorobutyl acrylate, 2,2,2-trifluoroethyl methacrylate, 2,2,3,3,3-pentafluoropropyl methacrylate, 2- (perfluorobutyl) ethyl methacrylate, 3 -(Perfluorobutyl) -2-hydroxypropylme Chryrate, 2- (perfluorohexyl) ethyl methacrylate, 3- (perfluorohexyl) -2-hydroxypropyl methacrylate, 2- (perfluorooctyl) ethyl methacrylate, 3-perfluorooctyl-2-hydroxypropyl methacrylate, 2- (Perfluorodecyl) ethyl methacrylate, 2- (perfluoro-3-methylbutyl) ethyl methacrylate, 3- (perfluoro-3-methylbutyl) -2-hydroxypropyl methacrylate, 2- (perfluoro-5-methylhexyl) ethyl Methacrylate, 3- (perfluoro-5-methylhexyl) -2-hydroxypropyl methacrylate, 2- (perfluoro-7-methyloctyl) ethyl methacrylate, 3- (perfluoro-7-methyloctyl) -2-hydroxypropyl Methacrylate, 1H, 1H, 3H-Tetraph Oropropyl methacrylate, 1H, 1H, 5H-octafluoropentyl methacrylate, 1H, 1H, 7H-dodecafluoroheptyl methacrylate, 1H, 1H, 9H-hexadecafluorononyl methacrylate, 1H-1- (trifluoromethyl) trifluoroethyl Methacrylate, 1H, 1H, 3H-hexafluorobutyl methacrylate and the like can be mentioned.

  As the fluorine-containing (meth) acrylate-based resin, a perfluoroalkyl ester and a partially fluorinated alkyl ester of (meth) acrylic acid, and a perfluoroalkyl group or a partially fluorinated alkyl group are linked through an organic linking group. In addition to homopolymers of fluorine-containing (meth) acrylates such as (meth) acrylic acid esters, the fluorine-containing (meth) acrylates and alkyl esters of (meth) acrylic acid such as methyl, ethyl, butyl, octyl and dodecyl; Examples thereof include copolymers with fluorine-free (meth) acrylates such as hydroxyalkyl esters such as hydroxyethyl and hydroxybutyl.

  Examples of the fluorine-containing olefin resin include polyvinylidene fluoride, polytetrafluoroethylene, vinylidene fluoride-tetrafluoroethylene copolymer, ethylene-tetrafluoroethylene copolymer, vinylidene fluoride-tetrafluoroethylene-hexafluoropropylene Examples thereof include an original copolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, a vinylidene fluoride-hexafluoropropylene copolymer, a polyvinyl fluoride, a polyvinyl fluoride ether, and a vinyl fluoride ether-tetrafluoroethylene copolymer.

  Examples of the non-cationically polymerizable silicon-containing compound include silicone oils, (meth) acryloxyalkylsilanes, silicon-containing (meth) acrylate resins, silicone resins, alkoxysilanes, and the like.

  As the silicone oils, general silicone oils can be used. The silicone oils may have a (meth) acryloyloxy group at the terminal. Commercially available products can be used as the silicone oils. For example, product names “X-22-164A”, product names “X-22-164B”, and product names “X-22-” manufactured by Shin-Etsu Chemical Co., Ltd. 164C ", product name" X-24-8201 ", product name" X-22-174DX ", product name" X-22-2426 ", product number" BX16-152B "manufactured by Toray Dow Corning Silicone Co., Ltd., product number" BY16-152 ", product number" BX2-152C ", product number" BX16-122A ", etc. can be used.

  Examples of the (meth) acryloxyalkylsilanes include 3-methacryloxypropyldichloromethylsilane, 3-acryloxypropyldimethoxymethylsilane, 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyldimethoxymethylsilane, 3- And methacryloxypropyltrimethoxysilane, 3-methacryloxypropyldiethoxymethylsilane, and 3-methacryloxypropyltriethoxysilane. As the (meth) acryloxyalkylsilanes, commercially available products can be used. For example, product numbers “LS-2080”, “LS-2826”, “LS-2827” manufactured by Shin-Etsu Chemical Co., Ltd., “LS-3375”, “LS-3380”, “LS-4548”, “LS-5118”, and the like can be used.

  Examples of the silicon-containing (meth) acrylate resin include a silicon-containing (meth) acrylate homopolymer such as a polysiloxane group-containing (meth) acrylate, the silicon-containing (meth) acrylate, and (meth) acrylic acid. Examples thereof include alkyl esters such as methyl, ethyl, butyl, octyl and dodecyl; and copolymers with (meth) acrylates not containing silicon such as hydroxyalkyl esters such as hydroxyethyl and hydroxybutyl. The copolymer further has a (meth) acrylic acid perfluoroalkyl ester and partially fluorinated alkyl ester, and a perfluoroalkyl group or partially fluorinated alkyl group linked via an organic linking group (meth). A small amount of a fluorine-containing (meth) acrylate such as an acrylate ester may be copolymerized.

  The silicone resin is, for example, a polymer having a three-dimensional network structure obtained by hydrolyzing and polymerizing organochlorosilanes. A trifunctional monomer such as methyltrichlorosilane and phenyltrichlorosilane is a main monomer, It is produced by combining bifunctional monomers such as dimethyldichlorosilane and diphenyldichlorosilane and monofunctional monomers such as chlorosilane.

  Examples of the alkoxysilanes include silicates such as methyl silicate, ethyl silicate, propyl silicate, and butyl silicate, and polymers thereof.

  In the raw material mixture, the total content of the fluorine-containing compound and the silicon-containing compound is preferably in the range of 0.5 to 10 parts by mass with respect to 100 parts by mass of the cationic polymerizable compound. If the total content of the fluorine-containing compound and the silicon-containing compound is less than 0.5 parts by mass, the slipperiness of the surface of the conductive roller may not be sufficiently improved. It may be lowered and peeling may occur.

  In order to impart conductivity to the cured product, a conductive agent may be added to the raw material mixture, and as the conductive agent, a carbon-based electronic conductive agent, an ionic conductive agent, and a transparent conductive agent are preferable. Carbon-based electronic conductive agents include conductive carbon such as ketjen black and acetylene black, carbon black for rubber such as SAF, ISAF, HAF, FEF, GPF, SRF, FT, and MT, and color for which oxidation treatment has been applied. Examples thereof include carbon black, pyrolytic carbon black, natural graphite, and artificial graphite. In addition, as the ionic conductive agent, tetraethylammonium, tetrabutylammonium, dodecyltrimethylammonium, hexadecyltrimethylammonium, benzyltrimethylammonium, modified fatty acid dimethylethylammonium and the like perchlorate, chlorate, hydrochloride, bromate , Iodate, borofluoride, sulfate, ethyl sulfate, carboxylate, sulfonate, etc. ammonium salt; alkali metal such as lithium, sodium, potassium, calcium, magnesium, alkaline earth metal Examples include chlorate, chlorate, hydrochloride, bromate, iodate, borofluoride, sulfate, trifluoromethyl sulfate, sulfonate, and the like. In addition, as the transparent conductive agent, fine particles of metal oxide such as ITO, tin oxide, titanium oxide, and zinc oxide; fine particles of metal such as nickel, copper, silver, germanium: conductive titanium oxide whisker, conductive barium titanate Examples thereof include conductive whiskers such as whiskers. The blending amount of the conductive agent is preferably 20 parts by mass or less, more preferably 0.01 to 20 parts by mass, and still more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the cationic polymerizable compound. When using a carbon-based electronic conductive agent, it is preferable to add a sensitizer from the viewpoint of sufficiently curing the raw material mixture by irradiation with ultraviolet rays. Examples include butoxyanthracene.

  The conductive roller of the present invention includes a shaft member 2 as in the conductive roller 1 shown in FIG. 1, and a layer (cured material layer 3) made of the cured product is disposed on the outer periphery of the shaft member 2. It is preferable. Further, the conductive roller of the present invention, like the conductive roller 1 shown in FIG. 2, includes a shaft member 2, an elastic layer 4 disposed on the outer side in the radial direction of the shaft member 2, and the elastic layer 4. It is also preferable that the coating layer 5 is provided on the radially outer side, and the coating layer 5 is made of the cured product.

  In the conductive roller of the present invention, the shaft member 2 is not particularly limited as long as it has good conductivity. Even if it is a solid body made of metal or resin as shown in FIGS. A hollow body made of metal or resin as shown in FIG. 4 may be used, or a composite body in which a resin base material is disposed on the outer periphery of a metal solid body as shown in FIG. 3 includes a cylindrical portion 2A and a pair of shaft portions 2B located at both ends of the cylindrical portion 2A. The composite shown in FIG. 4 includes a metal solid body 2C and the metal body 2C. It consists of a resin base material 2D disposed on the outer periphery of the solid body 2C. In addition, the shaft member 2 can be reduced in weight by using resin for a part or all of the shaft member 2. Therefore, even if the outer diameter of the shaft member 2 is increased, an increase in the mass of the shaft member 2 can be sufficiently suppressed.

  Examples of the material for the metal solid body and the metal hollow body include iron, stainless steel, and aluminum. The resin solid body, the resin hollow body, and the resin base material 2D may be made of polyacetal, polyamide 6, polyamide 6/6, polyamide 12, polyamide 4/6, polyamide 6/10, polyamide 6/12, Polyamide 11, Polyamide MXD6, Polybutylene terephthalate, Polyphenylene oxide, Polyphenylene sulfide, Polyethersulfone, Polycarbonate, Polyimide, Polyamideimide, Polyetherimide, Polysulfone, Polyetheretherketone, Polyethylene terephthalate, Polyarylate, Liquid crystal polymer, Polytetrafluoro Examples include ethylene, polypropylene, ABS resin, polystyrene, polyethylene, melamine resin, phenol resin, and silicone resin. Among these, polyacetal, polyamide 6/6, polyamide MXD6, polyamide 6/12, polybutylene terephthalate, polyphenylene ether, polyphenylene sulfide, and polycarbonate are preferable. These resins may be used alone or in combination of two or more.

  In addition, when using resin for the said shaft member 2, it is preferable to ensure sufficient electroconductivity by adding and disperse | distributing a electrically conductive agent to resin. Here, as the conductive agent dispersed in the resin, carbon black powder, graphite powder, carbon fiber, metal powder such as aluminum, copper and nickel, metal oxide powder such as tin oxide, titanium oxide and zinc oxide, conductive glass A powdered conductive agent such as powder is preferred. These electrically conductive agents may be used individually by 1 type, and may be used in combination of 2 or more type. Although the compounding quantity of this electrically conductive agent is not restrict | limited in particular, The range of 5-40 mass% is preferable with respect to the whole resin, and the range of 5-20 mass% is still more preferable.

  When the conductive roller of the present invention has the elastic layer 4 as shown in FIG. 2, the elastic layer 4 includes an elastomer and, if necessary, other components such as a conductive agent. Examples of the elastomer used for the elastic layer include polyurethane, silicone rubber, butyl rubber, ethylene-propylene-diene rubber (EPDM), acrylonitrile-butadiene rubber (NBR), natural rubber, styrene-butadiene rubber (SBR), chloroprene rubber, acrylic rubber, Examples include epichlorohydrin rubber (ECO), ethylene-vinyl acetate copolymer (EVA), and mixtures thereof. In the elastic layer, the elastomer may be used as a foam by chemically foaming the elastomer using a foaming agent, or mechanically entraining and foaming air like a polyurethane foam.

  Examples of the conductive agent used for the elastic layer include an ionic conductive agent and an electronic conductive agent. Examples of ionic conducting agents include tetraethylammonium, tetrabutylammonium, dodecyltrimethylammonium, hexadecyltrimethylammonium, benzyltrimethylammonium, and modified fatty acid dimethylethylammonium perchlorate, chlorate, hydrochloride, bromate, iodine Ammonium salts such as acid salts, borofluoride salts, sulfate salts, ethyl sulfate salts, carboxylate salts, sulfonate salts; alkali metals such as lithium, sodium, potassium, calcium, magnesium, and perchloric acids of alkaline earth metals Salt, chlorate, hydrochloride, bromate, iodate, borofluoride, sulfate, trifluoromethyl sulfate, sulfonate, and the like. Conductive carbon such as acetylene black, SAF, I Carbon black for rubber such as AF, HAF, FEF, GPF, SRF, FT, MT, carbon black for color with oxidation treatment, pyrolytic carbon black, natural graphite, artificial graphite, antimony-doped tin oxide, ITO, oxidation Metal oxides such as tin, titanium oxide and zinc oxide, metals such as nickel, copper, silver and germanium, conductive polymers such as polyaniline, polypyrrole and polyacetylene, carbon whiskers, graphite whiskers, titanium carbide whiskers, conductive potassium titanate Examples include whiskers, conductive barium titanate whiskers, conductive titanium oxide whiskers, and conductive zinc oxide whiskers.

The elastic layer preferably has a resistance value of 10 ³ to 10 ¹⁰ Ωcm, more preferably 10 ⁴ to 10 ⁸ Ωcm, depending on the blending of the conductive agent. If the resistance value of the elastic layer is less than 10 ³ Ωcm, the electric charge may leak to the photosensitive drum or the like, or the conductive roller itself may be broken by voltage, and if it exceeds 10 ¹⁰ Ωcm, the ground cover tends to occur. The hardness of the elastic layer is not particularly limited, but is preferably 80 degrees or less in terms of Asker C hardness, more preferably 20 to 70 degrees.

  The conductive roller of the present invention can be produced, for example, by applying the raw material mixture to the outer surface of a roller body formed by forming an elastic layer on the outer periphery of the shaft member and then irradiating with ultraviolet rays. Examples of the method for applying the raw material mixture include a spray method, a roll coater method, a dipping method, and a die coating method. Examples of the light source used for ultraviolet irradiation include a mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a metal halide lamp, and a xenon lamp. The conditions for ultraviolet irradiation are appropriately selected according to the components, composition, coating amount, and the like contained in the raw material mixture, and the irradiation intensity and the integrated light amount may be adjusted as appropriate.

  The conductive roller of the present invention described above can be used as a developing roller, a charging roller, a toner supply roller, a transfer roller, a paper feed roller, a cleaning roller, a fixing pressure roller, and the like of an image forming apparatus.

<Image forming apparatus>
The image forming apparatus of the present invention includes the above-described conductive roller, and preferably includes the conductive roller as at least one of the developing roller and the charging roller. The image forming apparatus of the present invention is not particularly limited except that the conductive roller is used, and can be manufactured by a known method.

  The image forming apparatus of the present invention will be described in detail below with reference to the drawings. FIG. 5 is a partial cross-sectional view of an example of the image forming apparatus of the present invention. The image forming apparatus of the illustrated example supplies a photosensitive member 6 holding an electrostatic latent image, a charging roller 7 that is positioned in the vicinity (upward in the drawing) of the photosensitive member 6 and charges the photosensitive member 6, and toner 8. A toner supply roller 9, a developing roller 10 disposed between the toner supply roller 9 and the photosensitive member 6, a stratifying blade 11 provided in the vicinity of the developing roller 10 (upward in the drawing), and a photosensitive member. 6 is provided with a transfer roller 12 located in the vicinity (lower in the drawing) 6 and a cleaning roller 13 disposed adjacent to the photoreceptor 6. The image forming apparatus of the present invention can further include a known component (not shown) that is usually used in the image layer forming apparatus.

  In the illustrated image forming apparatus, the charging roller 7 is brought into contact with the photosensitive member 6 and a voltage is applied between the photosensitive member 6 and the charging roller 7 to charge the photosensitive member 6 to a constant potential. Then, an electrostatic latent image is formed on the photoreceptor 6 by an exposure machine (not shown). Next, the photosensitive member 6, the toner supply roller 9, and the developing roller 10 rotate in the direction of the arrow in the drawing, so that the toner 8 on the toner supply roller 9 is sent to the photosensitive member 6 through the developing roller 10. It is done. The toner 8 on the developing roller 10 is adjusted to a uniform thin layer by the stratifying blade 11 and rotates while the developing roller 10 and the photosensitive member 6 are in contact with each other, so that the toner 8 is transferred from the developing roller 10 to the photosensitive member 6. It adheres to the electrostatic latent image and the latent image becomes visible. The toner 8 attached to the latent image is transferred to a recording medium such as paper by the transfer roller 12, and the toner 8 remaining on the photosensitive member 6 after the transfer is removed by the cleaning roller 13. Here, in the image forming apparatus of the present invention, at least one of the charging roller 7, the toner supply roller 9, the developing roller 10, the transfer roller 12 and the cleaning roller 13, preferably at least the charging roller 7 and the developing roller 10. On the other hand, an excellent image can be stably formed by using the conductive roller of the present invention described above.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

<Preparation of base material using urethane as elastic layer>
After adding 1.6 parts by weight of conductive carbon and 0.15 parts by weight of dibutyltin dilaurate to 100 parts by weight of a trifunctional and 9,000 molecular weight polyether polyol obtained by adding propylene oxide to glycerin and stirring sufficiently, the mixture is stirred for 20 minutes under reduced pressure. This was defoamed and used as a polyol component. The hydroxyl value of the polyol component was 19 mgKOH / g. On the other hand, polypropylene glycol-modified polymeric MDI having an NCO content of 11% was degassed for 20 minutes while stirring under reduced pressure, and this was used as an isocyanate component. The polyol component and isocyanate component are mixed at a high speed of 3000 rpm with a two-component casting machine so that the ratio of the polyol component to the isocyanate component is 101.75 / 13.70 (isocyanate index: 103). Was poured into a cylindrical mold set with a cored bar of φ6 mm, and heated and cured in a hot air circulating oven at 90 ° C. for 60 minutes. A urethane roller with a cored bar was taken out from the cylindrical mold to obtain a base material (roller body) having urethane as an elastic layer.

<Preparation of substrate using UV resin as elastic layer>
Conductive roller base material made of polybutylene terephthalate (PBT) resin with an outer diameter of 17.0 mm inserted with a metal shaft with an outer diameter of 6.0 mm, 60 parts by mass of urethane acrylate oligomer UV3700B [manufactured by Nippon Synthetic Chemical Co., Ltd.], acrylate monomer MTG- A [methoxytriethylene glycol acrylate, manufactured by Kyoeisha Chemical Co., Ltd.] 40 parts by mass, photoinitiator IRGACURE651 [2,2-dimethoxy-1,2-diphenylethane-1-one, Ciba Specialty Chemicals Co., Ltd. )] 1 part by weight, ion conductive agent MP100 [polyol complex salt of sodium perchlorate, manufactured by Akishima Chemical Co., Ltd.] 2 parts by weight of elastic layer material was applied by a die coater to a thickness of 1500 μm, and in a nitrogen atmosphere While rotating, UV irradiation was performed at a UV irradiation intensity of 700 mW / cm ² for 5 seconds to obtain a base material (roller body) having a UV resin as an elastic layer.

(Examples 1-13 and Comparative Examples 1-6)
A coating layer raw material mixture (coating liquid) having the composition shown in Tables 1 to 4 was applied to the outer peripheral surface of the base material obtained as described above with a roll coater at a thickness of 10 μm, and manufactured by Ushio Electric Co., Ltd. Using a UniCure UVH-0252C apparatus, ultraviolet rays (UV) were irradiated in the atmosphere at a UV irradiation intensity of 700 mW / cm ² for 5 seconds to form a coating film layer to obtain a conductive roller. The presence or absence of adhesiveness of the coating layer of the obtained conductive roller was confirmed. The obtained conductive roller was incorporated into an image forming apparatus as a developing roller or a charging roller and printed 10,000 sheets, and then the presence or absence of peeling of the coating layer, image characteristics, and presence of toner filmin were examined. These results are shown in Tables 1 to 4.

* 1 Made by Daicel-Cytech, (3,4-epoxycyclohexyl) methyl-3 ', 4'-epoxycyclohexylcarboxylate, epoxy equivalent = 128-145
* 2 Kyoeisha Chemical Co., Ltd., 1,6-hexanediol diglycidyl ether, epoxy equivalent = 140-160
* 3 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, manufactured by Toagosei Co., Ltd.
* 4 Kyoeisha Chemical, urethane acrylate oligomer
* 5 Kyoeisha Chemical Co., Ltd., 1,6-hexanediol diacrylate
* 6 Shin-Etsu silicone, alicyclic epoxy silicone on both ends, epoxy equivalent = 500
* 7 Shin-Etsu Silicone, both ends glycidyl ether type silicone, epoxy equivalent = 950
* 8 Shin-Etsu Silicone, both ends glycidyl ether type silicone, epoxy equivalent = 2700
* 9 Made from NOF, block copolymer
* 10 Kyoeisha Chemical, special silicone
* 11 Made by Daikin Chemical, 3-perfluorobutyl-1,2-epoxypropane
* 12 Made by Daikin Chemicals, 1,4-bis (2 ', 3'-epoxypropyl) -perfluoro-n-butane
* 13 Made from NOF, block copolymer
* 14 Aromatic sulfonium salt, manufactured by Sanshin Chemical Co., Ltd.
* 15 Bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, manufactured by Ciba Specialty Chemicals Co., Ltd.

  From Examples 1 to 13, by irradiating a raw material mixture containing a cationic polymerizable compound, a photocationic polymerization initiator, a fluorine-containing compound and / or a silicon-containing compound with ultraviolet rays, the raw material mixture is cured by cationic polymerization even in the air. As a result, a non-adhesive coating layer is formed and the surface slipperiness is excellent, so that it can be seen that even when incorporated in an image forming apparatus, toner filming does not occur and a good image can be formed.

  On the other hand, from Comparative Examples 1-2 and 4-5, when the raw material mixture containing no cationically polymerizable compound is irradiated with ultraviolet rays in the atmosphere, the raw material mixture is not sufficiently cured, and an adhesive coating layer is formed. You can see.

  Further, from Comparative Examples 3 and 6, when a raw material mixture containing no fluorine and / or silicon-containing compound was irradiated with ultraviolet rays in the atmosphere, a non-adhesive coating layer was formed, but toner filming occurred. , You can see that image defects occur.

It is sectional drawing of an example of the electroconductive roller of this invention. It is sectional drawing of the other example of the electroconductive roller of this invention. It is sectional drawing of an example of the metal or resin hollow body which can be used as a shaft member for the electroconductive roller of this invention. It is sectional drawing of an example of the composite_body | complex which arrange | positions the resin base material in the outer periphery of the metal solid body which can be used as a shaft member for the electroconductive roller of this invention. 1 is a partial cross-sectional view of an example of an image forming apparatus of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Conductive roller 2 Shaft member 2A Cylindrical part 2B Shaft part 2C Metal solid body 2D Resin base material 3 Hardened | cured material layer 4 Elastic layer 5 Coating layer 6 Photoconductor 7 Charging roller 8 Toner 9 Toner supply roller 10 Developing roller 11 Layering Blade 12 Transfer roller 13 Cleaning roller

Claims (10)

A cationically polymerizable compound;
At least one selected from the group consisting of fluorine-containing compounds and silicon-containing compounds;
An electroconductive roller provided with the hardened | cured material formed by cationically polymerizing the raw material mixture containing a photocationic polymerization initiator by ultraviolet irradiation.   The conductive roller according to claim 1, wherein the cationic polymerizable compound is at least one selected from the group consisting of a compound having an oxirane ring and vinyl ether.   The conductive roller according to claim 2, wherein the compound having an oxirane ring is at least one selected from the group consisting of an epoxy compound and an oxetane compound.   The conductive roller according to claim 1, wherein the raw material mixture includes at least one selected from the group consisting of a cationic polymerizable fluorine-containing compound and a cationic polymerizable silicon-containing compound.   The conductive roller according to claim 1, wherein the raw material mixture contains at least one selected from the group consisting of a non-cationically polymerizable fluorine-containing compound and a non-cationically polymerizable silicon-containing compound. The raw material mixture is
At least one selected from the group consisting of a cationic polymerizable fluorine-containing compound and a cationic polymerizable silicon-containing compound;
The conductive roller according to claim 1, comprising at least one selected from the group consisting of a non-cationically polymerizable fluorine-containing compound and a non-cationically polymerizable silicon-containing compound.   The conductive roller according to claim 1, further comprising a shaft member, wherein a layer made of the cured product is disposed on an outer periphery of the shaft member.   A shaft member; an elastic layer disposed radially outward of the shaft member; and a coating layer disposed radially outward of the elastic layer, wherein the coating layer is made of the cured product. The conductive roller according to claim 1.   8. The shaft member is a metal or resin solid body, a metal or resin hollow body, or a composite body in which a resin base material is disposed on an outer periphery of a metal solid body. Or the conductive roller of 8.   An image forming apparatus using the conductive roller according to claim 1.

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