Belt member for electrophotographic apparatus

Abstract

The present invention provides a belt member for an electrophotographic device, which, for long-term storage, suppresses the occurrence of wrinkles and bends, suppresses the sliding noise of a cleaning blade, and has a good appearance and good adhesion between a surface layer and a base layer. The belt member (10) for an electrophotographic device has a surface layer (14) on the outer peripheral surface of a cylindrical base layer (12), and the surface layer (14) is configured as a cured body of a resin composition containing 100 parts by mass of a fluororesin having a hydroxyl group, with respect to 100 parts by mass of the fluororesin having a hydroxyl group. The present invention relates to an adhesive composition comprising: 10-30 parts by mass of an isocyanate curing agent having isocyanate groups at both ends and having a molecular weight of 600-4000 g / mol, or 5-18 parts by mass of an isocyanate curing agent having an isocyanate group at a single end; from 5 parts by mass to 10 parts by mass (inclusive) of a fluorine-based surfactant; and 1.0-5 parts by mass (inclusive) of a silane coupling agent having an amino group or an isocyanate group.

Description

Technical Field

[0001] The present invention relates to a belt member for an electrophotographic device, and more particularly to a belt member for an electrophotographic device such as a conveyor belt or an intermediate transfer belt. Background Art

[0002] In belt components such as conveyor belts and intermediate transfer belts of electronic photographic equipment, as technologies for improving sliding properties with cleaning scrapers, there are known technologies for laminating polyimide-based coatings on the surface of polyimide-based base layers, laminating fluorine tubes, and laminating thermosetting fluorine resins to which silicone-based lubricants are added.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2008-094605

[0006] Patent Document 2: Japanese Patent Application Publication No. 2011-073804

[0007] Patent Document 3: International Publication No. 2022 / 071224 Summary of the invention

[0008] Problem that the invention aims to solve

[0009] The belt member is subjected to a force in a tensile direction through a biaxial process. Therefore, in the case of long-term storage or long-term use, wrinkles and bends may occur on the surface of the belt member, resulting in poor paper conveying during use. In addition, since the belt member abuts against the cleaning blade, sliding noises may be generated between the belt member and the cleaning blade as abnormal noises due to long-term use. Furthermore, in the belt member, if the adhesion between the base layer and the surface layer is insufficient, there is a risk of peeling of the surface layer.

[0010] The problem to be solved by the present invention is to provide a belt member for an electrophotographic device which can suppress the generation of wrinkles and bends during long-term storage and use, suppress the sliding noise of a cleaning blade, improve the appearance, and improve the adhesion between the surface layer and the base layer.

[0011] Means used to solve problems

[0012] The belt member for an electrophotographic device according to the present invention comprises a cylindrical base layer and a surface layer formed on the outer peripheral surface of the base layer, the base layer contains at least one of polyimide and polyamideimide, and the surface layer is constituted as a cured product of a resin composition containing a fluororesin having a hydroxyl group, an isocyanate curing agent, a fluorine-based surfactant, and a silane coupling agent having an amino group or an isocyanate group, the isocyanate curing agent having isocyanate groups at both ends and having a molecular weight of 600 g / mol or more and 4000 g / mol or less, and with respect to 100 parts by mass of the fluororesin, the isocyanate curing agent is 10 parts by mass or more and 30 parts by mass or less, the fluorine-based surfactant is 5 parts by mass or more and 10 parts by mass or less, and the silane coupling agent is 1.0 parts by mass or more and 5 parts by mass or less.

[0013] In addition, another belt member for an electrophotographic device involved in the present invention comprises a cylindrical base layer and a surface layer formed on the outer peripheral surface of the base layer, the base layer contains at least one of polyimide and polyamideimide, and the surface layer is constituted as a cured product of a resin composition containing a fluororesin having a hydroxyl group, an isocyanate curing agent, a fluorine-based surfactant, and a silane coupling agent having an amino group or an isocyanate group, the isocyanate curing agent having an isocyanate group at one end, and the isocyanate curing agent is 5 parts by mass or more and 18 parts by mass or less, the fluorine-based surfactant is 5 parts by mass or more and 10 parts by mass or less, and the silane coupling agent is 1.0 parts by mass or more and 5 parts by mass or less, relative to 100 parts by mass of the fluororesin.

[0014] The fluorine content of the fluorine-based surfactant is preferably 10% by mass or more and 30% by mass or less. The dynamic friction coefficient and static friction coefficient after 500 wear tests are preferably 0.5 or less.

[0015] (1) The belt member for an electrophotographic apparatus according to the present invention comprises a cylindrical base layer and a surface layer formed on the outer peripheral surface of the base layer, the base layer containing at least one of polyimide and polyamideimide, and the surface layer being a cured product of a resin composition containing a fluororesin having a hydroxyl group, an isocyanate curing agent, a fluorine-based surfactant, and a silane coupling agent having an amino group or an isocyanate group, the isocyanate curing agent having isocyanate groups at both ends and having a molecular weight of 600 g / mol to 4000 g / mol, and the amount of the isocyanate curing agent being 10 parts by mass to 30 parts by mass, the amount of the fluorine-based surfactant being 5 parts by mass to 10 parts by mass, and the amount of the silane coupling agent being 1.0 parts by mass to 5 parts by mass.

[0016] (2) In addition, another belt member for an electrophotographic device involved in the present invention comprises a cylindrical base layer and a surface layer formed on the outer peripheral surface of the base layer, the base layer contains at least one of polyimide and polyamide-imide, and the surface layer is constituted as a cured product of a resin composition containing a fluororesin having a hydroxyl group, an isocyanate curing agent, a fluorine-based surfactant, and a silane coupling agent having an amino group or an isocyanate group, the isocyanate curing agent having an isocyanate group at one end, and the isocyanate curing agent is 5 parts by mass or more and 18 parts by mass or less, the fluorine-based surfactant is 5 parts by mass or more and 10 parts by mass or less, and the silane coupling agent is 1.0 parts by mass or more and 5 parts by mass or less, based on 100 parts by mass of the fluororesin.

[0017] (3) In the above (1) or (2), the fluorine content of the fluorine-based surfactant is preferably 10 mass % or more and 30 mass % or less.

[0018] (4) In any one of the above (1) to (3), the dynamic friction coefficient and the static friction coefficient after 500 wear tests are preferably 0.5 or less.

[0019] Effects of the Invention

[0020] According to the belt member for an electrophotographic device involved in the present invention, the surface layer is constituted by a cured product of a resin composition containing a fluororesin having a hydroxyl group, an isocyanate curing agent, a fluorine-based surfactant, and a silane coupling agent having an amino group or an isocyanate group, the isocyanate curing agent having isocyanate groups at both ends and having a molecular weight of 600 g / mol or more and 4000 g / mol or less, and the isocyanate curing agent is 10 parts by mass or more and 30 parts by mass or less, the fluorine-based surfactant is 5 parts by mass or more and 10 parts by mass or less, and the silane coupling agent is 1.0 parts by mass or more and 5 parts by mass or less, so that the generation of wrinkles and bends can be suppressed during long-term storage and use, the sliding sound of the cleaning blade can be suppressed, the appearance can be improved, and the adhesion between the surface layer and the base layer can be improved.

[0021] In addition, according to another belt member for an electrophotographic device involved in the present invention, the surface layer is constituted by a cured product of a resin composition containing a fluororesin having a hydroxyl group, an isocyanate curing agent, a fluorine-based surfactant, and a silane coupling agent having an amino group or an isocyanate group, the isocyanate curing agent having an isocyanate group at one end, and the isocyanate curing agent is 5 parts by mass or more and 18 parts by mass or less, the fluorine-based surfactant is 5 parts by mass or more and 10 parts by mass or less, and the silane coupling agent is 1.0 parts by mass or more and 5 parts by mass or less, relative to 100 parts by mass of the fluororesin. Therefore, the generation of wrinkles and warps can be suppressed during long-term storage and use, the sliding sound of the cleaning blade can be suppressed, the appearance can be improved, and the adhesion between the surface layer and the base layer can be improved.

[0022] If the isocyanate curing agent has isocyanate groups at both ends and has a molecular weight of 600 g / mol or more and 4000 g / mol or less, the surface layer becomes soft and wrinkles and warps can be suppressed during long-term storage and use.

[0023] In addition, when the isocyanate curing agent has an isocyanate group at one end, the surface layer becomes soft and the occurrence of wrinkles and warps can be suppressed during long-term storage and use.

[0024] Furthermore, when the fluorine content of the fluorine-based surfactant is 10% by mass or more and 30% by mass or less, the sliding property of the surface layer is improved, and the effect of suppressing the sliding noise of the cleaning blade is excellent.

[0025] Furthermore, when the dynamic friction coefficient and the static friction coefficient after 500 abrasion tests are 0.5 or less, the surface layer has excellent sliding properties and the effect of suppressing the sliding noise of the cleaning blade is excellent. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a perspective view schematically showing a belt member for an electrophotographic apparatus according to one embodiment of the present invention.

[0027] Figure 2 yes Figure 1 A sectional view of a belt member for an electrophotographic apparatus is shown. DETAILED DESCRIPTION

[0028] The belt member for an electrophotographic device according to the present invention (hereinafter, sometimes simply referred to as a belt member) is described in detail. The belt member comprises an elastic layer and a surface layer formed on the outer peripheral surface of the elastic layer. The belt member is preferably used as an endless belt such as an intermediate transfer belt, a paper transfer conveyor belt, a fixing belt, etc., used in an electrophotographic device such as a copier, a printer, a fax, etc. that adopts an electrophotographic method.

[0029] Figure 1A belt member according to one embodiment of the present invention is shown. Figure 2 express Figure 1 A cross-sectional view of the belt member is shown.

[0030] The belt member 10 includes a cylindrical base layer 12 and a surface layer 14 formed on the outer peripheral surface of the base layer 12. The belt member 10 is configured as an endless belt.

[0031] The base layer 12 becomes the base material of the belt component 10. The base layer 12 is formed into a cylindrical shape and has a seamless structure without seams in the circumferential direction. The base layer 12 contains at least one of polyimide and polyamide-imide. Polyimide and polyamide-imide can also be functionally modified. Polyimide and polyamide-imide have excellent rigidity and durability, so they can be preferably used as the constituent material of the base layer 12 of the belt component 10. In particular, it is preferred to use polyimide to constitute the base layer 12. As long as the base layer 12 contains at least one of polyimide and polyamide-imide as the main component, it may also contain other components such as additives. As additives, conductive agents such as carbon black and graphite, fillers such as calcium carbonate, release agents, flame retardants, leveling agents, defoaming agents, etc. can be listed.

[0032] The thickness of the base layer 12 is not particularly limited. The thickness of the base layer 12 is preferably, for example, 50 μm or more and 60 μm or more, and preferably 90 μm or less and 80 μm or less.

[0033] The surface layer 14 is constituted as a cured product of a resin composition containing a fluororesin having a hydroxyl group, an isocyanate curing agent, a fluorine-based surfactant, and a silane coupling agent having an amino group or an isocyanate group.

[0034] Fluororesin is the main component constituting the surface layer 14 and plays a role as a binder polymer. Fluororesin is not particularly limited as long as it can be used as a coating. Examples of fluororesin include fluoroethylene vinyl ether copolymer (FEVE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene resin (PCTFE), etc. Fluororesin having a hydroxyl group can be cured by reacting with a carbamate of an isocyanate curing agent.

[0035] Isocyanate curing agent functions as a curing agent for fluororesin having a hydroxyl group. As isocyanate curing agent, monoisocyanate and polyisocyanate can be listed. Isocyanate curing agent can be an isocyanate curing agent having isocyanate groups (functional groups) at both ends, or an isocyanate curing agent having isocyanate groups (functional groups) at one end. It is preferred that an isocyanate curing agent be used that has an effect on the softening of the cured product.

[0036] For isocyanate curing agents having isocyanate groups at both ends, isocyanate curing agents with relatively large molecular weights are preferred. In particular, if the distance between crosslinks becomes larger, it can be more helpful to soften the cured body. From this viewpoint, in isocyanate curing agents having isocyanate groups at both ends, the molecular weight is preferably 600g / mol or more. More preferably, it is 1000g / mol or more, further preferably 1500g / mol or more, and particularly preferably 2000g / mol or more. On the other hand, if the molecular weight of the isocyanate curing agent having isocyanate groups at both ends is too large, the sliding sound of the cleaning blade tends to become larger. Therefore, as the molecular weight of the isocyanate curing agent having isocyanate groups at both ends, it is preferably 4000g / mol or less. More preferably, it is 3500g / mol or less, and further preferably 3000g / mol or less. For the molecular weight of the isocyanate curing agent, the molecular weight of the oligomer or polymer is represented by the number average molecular weight.

[0037] As the isocyanate curing agent having isocyanate groups at both ends, an NCO-terminated urethane prepolymer obtained by reacting polyisocyanate with a polyol may be used.

[0038] Examples of the polyisocyanate include diphenylmethane diisocyanate (MDI), polymethylene polyphenylene polyisocyanate (polymeric MDI), crude MDI (c-MDI) which is a mixture of MDI and polymeric MDI, dicyclohexylmethane diisocyanate (hydrogenated MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), trimethylhexamethylene diisocyanate (TMHDI), isophorone diisocyanate (IPDI), o-toluidine diisocyanate (TODI), naphthalene diisocyanate (NDI), xylylene diisocyanate (XDI), p-phenylene diisocyanate (PDI), lysine diisocyanate (LDI), dimethyl diisocyanate (DDI), MDI ureate, HDI ureate, TDI ureate as a polymer, and modified products thereof obtained by ureidation, biuretation, allophanation, carbodiimidation, urethanation, etc., and the like. As the polyisocyanate, from the viewpoint of imparting flexibility, easiness of reaction, and the like, aliphatic polyisocyanates such as HDI are preferred.

[0039] Examples of the polyol include polyester polyol, polyether polyol, polycaprolactone polyol, polycarbonate polyol, etc. As the polyol, polyether polyol is particularly preferred from the viewpoint of stability (hydrolyzability) in a high-temperature and high-humidity environment.

[0040] Examples of the polyester polyol include polyethylene adipate (PEA), polybutylene adipate (PBA), polyhexylene adipate (PHA), and a copolymer of ethylene adipate and butylene adipate (PEA / BA).

[0041] Examples of the polyether polyol include polypropylene glycol (PPG), polytetramethylene glycol (PTMG), ethylene oxide-modified polyols thereof, and polyethylene glycol (PEG).

[0042] Polycarbonate polyol (polycarbonate diol) is obtained by polymerizing a low molecular carbonate compound using an alkylene glycol as a monomer. Examples of the alkylene glycol as a monomer include 1,6-hexanediol, 1,5-pentanediol, 1,4-butanediol, and cyclohexanedimethanol.

[0043] In the resin composition, the content of the isocyanate curing agent having an isocyanate group at both ends is 10 parts by mass or more and 30 parts by mass or less relative to 100 parts by mass of the fluororesin. If the content of the isocyanate curing agent having an isocyanate group at both ends is less than 10 parts by mass relative to 100 parts by mass of the fluororesin, the flexibility is insufficient, and wrinkles and bends are generated in the surface layer 14 due to long-term storage and use. In addition, from this viewpoint, the content of the isocyanate curing agent having an isocyanate group at both ends is more preferably 15 parts by mass or more. On the other hand, if the isocyanate curing agent having an isocyanate group at both ends is too much, the sliding sound of the cleaning blade becomes larger. Therefore, relative to 100 parts by mass of the fluororesin, the content of the isocyanate curing agent having an isocyanate group at both ends is less than 30 parts by mass. In addition, from this viewpoint, the content of the isocyanate curing agent having an isocyanate group at both ends is more preferably less than 25 parts by mass, and further preferably less than 20 parts by mass.

[0044] Since the isocyanate curing agent having an isocyanate group at one end is not an isocyanate curing agent that forms a crosslinked structure with the fluororesin having a hydroxyl group, it can further contribute to the softening of the cured product by performing a urethane reaction. From this viewpoint, there is no particular limitation on the molecular weight of the isocyanate curing agent having an isocyanate group at one end.

[0045] Examples of the isocyanate curing agent having an isocyanate group at one terminal include aliphatic or aromatic monoisocyanates.

[0046] In the resin composition, the content of the isocyanate curing agent having an isocyanate group at one end is 5 parts by mass or more and 18 parts by mass or less relative to 100 parts by mass of the fluororesin. If the content of the isocyanate curing agent having an isocyanate group at one end is less than 5 parts by mass relative to 100 parts by mass of the fluororesin, the flexibility is insufficient, and wrinkles and bends are generated in the surface layer 14 due to long-term storage and use. In addition, from this viewpoint, the content of the isocyanate curing agent is more preferably 7 parts by mass or more. On the other hand, if there are too many isocyanate curing agents having an isocyanate group at one end, the sliding sound of the cleaning blade becomes larger. Therefore, relative to 100 parts by mass of the fluororesin, the content of the isocyanate curing agent having an isocyanate group at one end is less than 18 parts by mass. In addition, from this viewpoint, the content of the isocyanate curing agent having an isocyanate group at one end is more preferably less than 15 parts by mass.

[0047] Fluorine-based surfactants improve the slippage of the surface of the surface layer 14. Fluorine-based surfactants are composed of compounds having fluorine-containing groups. Preferably, the side chain of the compound has a fluorine-containing group. As the above-mentioned compound, polymers having fluorine-containing groups, acrylic fluorine copolymers, acrylic fluorine-acrylic copolymers, acrylic fluorine-acrylic silicone-acrylic copolymers, perfluoropolyethers, perfluoropolyether alcohols, etc. can be cited. As polymers, there are no particular restrictions, and from the viewpoints of compatibility with the fluorine coating containing the above-mentioned fluororesins, (meth) acrylic polymers are preferably used.

[0048] As the fluorine-containing group, an organic group containing fluorine can be cited. As the organic group containing fluorine, a fluoroalkyl group having 1 to 20 carbon atoms can be cited. The fluoroalkyl group can be a perfluoroalkyl group in which all hydrogen atoms of the alkyl group are substituted by fluorine atoms, or a fluoroalkyl group in which part of the hydrogen atoms of the alkyl group are substituted by fluorine atoms. Among them, a perfluoroalkyl group is preferred from the viewpoint of being easily localized on the surface of the surface layer 14.

[0049] Examples of the fluoroalkyl group having 1 to 20 carbon atoms include a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a nonafluorobutyl group, a perfluorohexyl group, a trifluoroethyl group, a pentafluoropropyl group, and a heptafluorobutyl group.

[0050] The (meth)acrylic polymer refers to a copolymer of (meth)acrylate, a copolymer of (meth)acrylamide, a copolymer of (meth)acrylate and (meth)acrylamide, etc. For example, a copolymer having an organic group containing fluorine can be obtained by copolymerizing a (meth)acrylate having an organic group containing fluorine and a (meth)acrylate having an organic group not containing fluorine.

[0051] The (meth)acrylic polymer may also contain copolymerizable non-modified (meth)acrylates and non-modified (meth)acrylamide as copolymerization components. As non-modified (meth)acrylates, alkyl (meth)acrylates, hydroxyalkyl (meth)acrylates, etc. may be cited. As alkyl (meth)acrylates, methyl (meth)acrylates, ethyl (meth)acrylates, propyl (meth)acrylates, butyl (meth)acrylates, 2-ethylhexyl (meth)acrylates, etc. may be cited. As hydroxyalkyl (meth)acrylates, hydroxyethyl (meth)acrylates, hydroxypropyl (meth)acrylates, hydroxybutyl (meth)acrylates, etc. may be cited. Among them, from the viewpoints of copolymerization reactivity, methyl (meth)acrylate is preferred.

[0052] As copolymerizable non-modified (meth)acrylamide, (meth)acrylamide, alkyl (meth)acrylamide, hydroxyalkyl (meth)acrylamide, etc. can be cited. As alkyl (meth)acrylamide, methyl (meth)acrylamide, ethyl (meth)acrylamide, propyl (meth)acrylamide, butyl (meth)acrylamide, 2-ethylhexyl (meth)acrylamide, etc. can be cited. As hydroxyalkyl (meth)acrylamide, hydroxyethyl (meth)acrylamide, hydroxypropyl (meth)acrylamide, hydroxybutyl (meth)acrylamide, etc. can be cited. Among them, from the viewpoint of copolymerization reactivity, methyl (meth)acrylamide is preferred.

[0053] From the viewpoint that the fluorine-based surfactant is easily biased on the surface of the surface layer 14, and the effect of improving the slipperiness of the surface is excellent, the fluorine content of the fluorine-based surfactant is preferably 10% by mass or more. More preferably, it is 15% by mass or more. In addition, from the viewpoint that the effect of making the appearance of the surface layer 14 good is excellent, the fluorine content of the fluorine-based surfactant is preferably 30% by mass or less. More preferably, it is 25% by mass or less. The fluorine content of the fluorine-based surfactant can be measured by GC-MS analysis, NMR analysis, etc.

[0054] In the resin composition, the content of the fluorine-based surfactant is 5 parts by mass or more and 10 parts by mass or less relative to 100 parts by mass of the fluorine resin. If the content of the fluorine-based surfactant is less than 5 parts by mass relative to 100 parts by mass of the fluorine resin, the effect of improving the sliding property of the surface is insufficient, and the sliding sound of the cleaning blade becomes larger. In addition, from this viewpoint, the content of the fluorine-based surfactant is more preferably 7 parts by mass or more. On the other hand, if the content of the fluorine-based surfactant exceeds 10 parts by mass relative to 100 parts by mass of the fluorine resin, defects are generated on the surface of the coating film, and the appearance of the surface of the surface layer 14 deteriorates. In addition, from this viewpoint, the content of the fluorine-based surfactant is more preferably 8 parts by mass or less.

[0055] The silane coupling agent improves the adhesion between the base layer 12 and the surface layer 14. The silane coupling agent has an amino group or an isocyanate group in order to form a bond with both the base layer 12 and the surface layer 14.

[0056] Examples of the silane coupling agent (amine-based) having an amino group include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, and N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane.

[0057] In the resin composition, the content of the silane coupling agent is 1.0 mass parts or more and 5 mass parts or less relative to 100 mass parts of the fluororesin. If the content of the silane coupling agent is less than 1.0 mass parts relative to 100 mass parts of the fluororesin, the adhesion between the base layer 12 and the surface layer 14 is insufficient. In addition, from this viewpoint, the content of the silane coupling agent is more preferably 2 mass parts or more. On the other hand, if the content of the silane coupling agent exceeds 5 mass parts relative to 100 mass parts of the fluororesin, wrinkles and bends are generated in the surface layer 14 due to long-term storage and use. In addition, from this viewpoint, the content of the silane coupling agent is more preferably 3 mass parts or less.

[0058] The resin composition constituting the surface layer 14 may also contain other components such as additives in addition to fluororesins, isocyanate curing agents, fluorine-based surfactants, and silane coupling agents. Examples of additives include conductive agents, fillers, mold release agents, flame retardants, leveling agents, and defoaming agents.

[0059] In addition, the surface layer 14 is formed into a cured body of the above-mentioned resin composition, and the dynamic friction coefficient and the static friction coefficient after 500 wear tests are preferably 0.5 or less. The dynamic friction coefficient and the static friction coefficient can be adjusted by the selection of fluorine-based surfactants, the adjustment of the content, the selection of isocyanate curing agents, the adjustment of the content, etc. The dynamic friction coefficient and the static friction coefficient of the surface layer 14 can be measured using a friction wear meter.

[0060] The thickness of the surface layer 14 is not particularly limited. By making it relatively thin, it is easy to suppress the generation of wrinkles and bends in the surface layer 14 for long-term storage and use. From this point of view, the thickness of the surface layer 14 is preferably 60 μm or less. More preferably, it is 50 μm or less. In addition, from the viewpoint of being easier to exert the effect of the surface layer 14, the thickness of the surface layer 14 is preferably 20 μm or more. More preferably, it is 30 μm or more.

[0061] The belt component 10 can be manufactured as follows. First, a base layer 12 is formed. Regarding the base layer 12, a base layer forming material in the form of a coating using a solvent or the like is applied to the outer peripheral surface of a cylindrical or columnar mold and dried. Heat treatment can also be performed as needed. As coating methods, dip coating, dispenser coating (nozzle coating), roller coating, ring coating, etc. can be listed. Next, a resin composition for the surface layer is applied to the surface of the formed base layer 12 and cured to form a surface layer 14. At this time, as needed, the curing of the resin composition can be promoted by heat treatment. For the coating of the resin composition, various techniques similar to those listed in the above section regarding the formation of the base layer 12 can be used. Finally, as long as the mold is removed, a belt component 10 with a surface layer 14 formed on the outer peripheral surface of the base layer 12 can be obtained.

[0062] According to the belt component 10 constructed as above, the surface layer 14 is constituted as a cured product of a resin composition comprising a fluororesin having a hydroxyl group, an isocyanate curing agent, a fluorine-based surfactant, and a silane coupling agent having an amino group or an isocyanate group, and each component is blended in a specific amount, thereby suppressing the generation of wrinkles and bends during long-term storage and use, suppressing the sliding sound of the cleaning scraper and making the appearance good, and making the adhesion between the surface layer 14 and the base layer 12 good.

[0063] In the resin composition, the isocyanate curing agent contributes to the softening of the surface layer 14. Thus, the generation of wrinkles and bends can be suppressed for long-term storage and use. If the isocyanate curing agent has isocyanate groups at both ends and its molecular weight is 600 g / mol or more and 4000 g / mol or less, the surface layer 14 becomes soft, and the generation of wrinkles and bends can be suppressed for long-term storage and use. In addition, if the isocyanate curing agent has an isocyanate group at one end, the surface layer 14 becomes soft, and the generation of wrinkles and bends can be suppressed for long-term storage and use.

[0064] In the resin composition, the fluorine-based surfactant contributes to the sliding property of the surface. Thus, the effect of suppressing the sliding sound of the cleaning blade is improved. In addition, if the fluorine content of the fluorine-based surfactant is 10% by mass or more and 30% by mass or less, the sliding property of the surface layer 14 is improved, and the effect of suppressing the sliding sound of the cleaning blade is excellent. There is a risk that the sliding property of the surface will deteriorate due to the softening of the surface layer 14, but in the resin composition, since the fluorine-based surfactant that improves the sliding property of the surface is added, the deterioration of the sliding property of the surface caused by the softening of the surface layer 14 is suppressed.

[0065] In the resin composition, the silane coupling agent contributes to the adhesion between the surface layer 14 and the base layer 12. The silane coupling agent may deteriorate the flexibility of the surface layer 14, but since the isocyanate curing agent that softens the surface layer 14 is added to the resin composition, the deterioration of flexibility caused by the silane coupling agent is suppressed, and the generation of wrinkles and warps can be suppressed for long-term storage and use.

[0066] Example

[0067] Hereinafter, the present invention will be described in detail using Examples and Comparative Examples. The present invention is not limited to the following Examples.

[0068] <Synthesis of fluorinated surfactants>

[0069] The raw materials of the composition shown in Table 1 and methyl isobutyl ketone (MIBK) were placed in a 0.5 L flask so that the solid content was 50%. After nitrogen bubbling for 5 minutes while stirring the contents of the flask, the temperature of the internal liquid was maintained at 100° C. and a polymerization reaction was carried out for 10 hours. Thereafter, MIBK was added to the flask so that the solid content was 30%, and copolymer solutions were obtained as fluorine-based surfactants <1> to <5>.

[0070] The following raw materials were used for the synthesis of the fluorine-based surfactant. The fluorine concentration (F concentration) is a concentration calculated from the amount of each raw material used.

[0071] ·MMA: Methyl methacrylate (manufactured by Tokyo Chemical Industry) (molecular weight: 100.12)

[0072] ·BMA: Butyl methacrylate (manufactured by Tokyo Chemical Industry) (molecular weight: 128.17)

[0073] ·2-(Perfluorohexyl)ethyl acrylate (manufactured by Daikin Chemicals Sales Co., Ltd.) (molecular weight: 418.15)

[0074] · Initiator (free radical polymerization initiator): 1,1'-azobis(cyclohexane-1-carbonitrile) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) (molecular weight: 244.34)

[0075] Table 1

[0076]

[0077] *Contains F acrylate: 2-(perfluorohexyl)ethyl acrylate

[0078] <Synthesis of Isocyanate Curing Agent <5>>

[0079] A four-necked flask equipped with a stirrer, a thermometer, a circulating cooling tube, a nitrogen blowing tube, and a dropping funnel was placed in a nitrogen atmosphere, and 60 g of HDI (hexamethylene diisocyanate) (manufactured by Tokyo Chemical Industry) and 62.5 g of a divalent polyether polyol ("PREMINOL G-5000" manufactured by Asahi Glass, number average molecular weight 5000) (equivalent ratio of isocyanate group / hydroxyl group 30 / 1) were added, and stirred under a nitrogen atmosphere. The temperature in the reactor was maintained at 160° C. for 3 hours. Then, the temperature of the reaction liquid was lowered, and unreacted HDI was removed using a thin film evaporator. The number average molecular weight of the obtained dual-terminal isocyanate polymer (isocyanate curing agent <5>) was 5000.

[0080] Other materials for forming the surface layer are as follows.

[0081] Fluorine resin: "campefluo EX" manufactured by Kansai Paint

[0082] · Isocyanate curing agent <1>: Uniroyal "Adiprene bl-16" (number average molecular weight 2000-3000)

[0083] Isocyanate curing agent <2>: CORONATE 2412 manufactured by Nippon Polyurethane (number average molecular weight 600-2000)

[0084] ・Isocyanate curing agent <3>: Millionat e 0”(Molecular weight 296)

[0085] ・Isocyanate curing agent <4>: DIC manufactured "BURNOCK DB-980K" (molecular weight 504)

[0086] Silane coupling agent: Shin-Etsu Chemical Co., Ltd. "KBM-903"

[0087] <Preparation of surface layer forming composition>

[0088] The surface layer forming composition was prepared by mixing the respective components in parts by mass shown in Tables 2 to 4.

[0089] <Production of belt components>

[0090] A coating liquid containing polyimide ("HCI-1300" manufactured by Hitachi Chemical Industries) was applied to the surface of a cylindrical mold by dip coating, and heated at 120°C for 30 minutes, 150°C for 10 minutes, 200°C for 10 minutes, 250°C for 10 minutes, and 350°C for 10 minutes to form a base layer (thickness 70 μm). Next, a surface layer forming composition was applied to the surface of the base layer by dip coating, and heated and cured at 160°C for 30 minutes to form a surface layer having the thickness described in Tables 2 to 4. Next, the mold was removed to produce a belt member.

[0091] The produced belt members were evaluated for the following bending, sliding noise, appearance, and adhesion. In addition, the friction coefficient of the surface of the produced belt member was measured.

[0092] (bending)

[0093] The produced belt member was set in a paper conveying unit ("WF-C20590" manufactured by Seiko Epson) and left for 5 days under an environment of 32.5°C × 90% RH. Thereafter, the belt member was rotated 1 / 4, and the case where the height of the deflection generated at the position where the rotating shaft was in contact before the rotation was 0.7 mm or less was rated as "◎", the case where it was more than 0.7 mm and less than 0.9 mm was rated as "○", and the case where it was more than 0.9 mm was rated as "×".

[0094] (Slide sound)

[0095] The produced belt member was set in a paper conveying unit ("WF-C20590" manufactured by Seiko Epson), and the belt member was rotated at a peripheral speed of 420 mm / sec. The case where no sliding sound was generated due to contact with the cleaning blade for more than 250 hours was marked as "◎", the case where sliding sound was generated during more than 200 hours and less than 250 hours was marked as "○", and the case where sliding sound was generated within 200 hours was marked as "×".

[0096] (Appearance)

[0097] In the process of producing the belt member, the surface layer forming composition was applied to the base layer, and the case where defects occurred on the coating surface during the curing reaction at 160°C for 30 minutes was marked as "×", and the case where no defects (sinking, cracking, wrinkling, bubbles, bleeding) occurred was marked as "○".

[0098] (Adhesion)

[0099] A 1 mm square × 50 grid incision was made on the surface of the tape component, and an adhesive tape ("P-422" manufactured by Nitto Denko) was pasted. When only the tape was peeled off, the case where the grids on the surface were not peeled off at all was marked as "◎", the case where the number of peeled grids was 1 was marked as "○", and the case where the number of peeled grids was 2 or more was marked as "×" (grid method).

[0100] (Coefficient of friction)

[0101] A belt member was placed on the base of a tribometer ("Triboster 500" manufactured by Kyowa Interface Science Co., Ltd.), and a wear test was performed 500 times on the surface side of the belt member at a speed of 2.5 mm / s using a wire indenter. The static friction coefficient and dynamic friction coefficient at the 500th time were measured.

[0102]

[0103]

[0104]

[0105] In Comparative Example 1, the content of the isocyanate curing agent in the surface layer forming composition was too little, and the surface of the belt member was bent. In Comparative Example 2, the content of the isocyanate curing agent in the surface layer forming composition was too much, and the sliding sound was not suppressed. In Comparative Example 3, the isocyanate curing agent in the surface layer forming composition had functional groups at both ends and its molecular weight was small, so the surface of the belt member was bent. In Comparative Example 4, the isocyanate curing agent in the surface layer forming composition had functional groups at both ends and its molecular weight was large, so the sliding sound was not suppressed. In Comparative Example 5, the isocyanate curing agent in the surface layer forming composition had a functional group at one end, the content of the isocyanate curing agent was too much, and the sliding sound was not suppressed.

[0106] In Comparative Example 6, the content of the fluorine-based surfactant in the surface-forming composition is small, so the effect of improving the sliding property of the surface is poor, and the sliding sound is not suppressed. In Comparative Example 7, the content of the fluorine-based surfactant in the surface-forming composition is large, so defects are generated on the surface of the coating film when the surface layer is formed, and the appearance is poor. In Comparative Example 8, the content of the silane coupling agent in the surface-forming composition is small, so the adhesion between the base layer and the surface layer is poor. In Comparative Example 9, the content of the silane coupling agent in the surface-forming composition is large, so the surface of the belt member is bent. In Comparative Example 10, the surface-forming composition does not contain a fluorine-based surfactant, so the sliding property of the surface is poor, and the sliding sound is not suppressed. In Comparative Example 11, the surface-forming composition does not contain a silane coupling agent, so the adhesion between the base layer and the surface layer is poor.

[0107] On the other hand, in the embodiment, the composition for forming the surface layer comprises a fluororesin having a hydroxyl group, an isocyanate curing agent, a fluorine-based surfactant, and a silane coupling agent having an amino group or an isocyanate group, each component is a specific amount, the isocyanate curing agent has an isocyanate group at both ends, and its molecular weight is 600 g / mol or more and 4000 g / mol or less, or the isocyanate curing agent has an isocyanate group at one end. Moreover, according to the embodiment, the occurrence of surface bending of the belt member is suppressed, the sliding sound of the cleaning blade is suppressed, no defects are observed on the coating surface when the surface layer is formed, the appearance is good, and the adhesion between the surface layer and the base layer is excellent.

[0108] Moreover, according to Example 1, Example 2, and Example 7, it can be seen that if the content of the isocyanate curing agent having isocyanate groups at both ends is 15 parts by mass or more and 25 parts by mass or less relative to 100 parts by mass of the fluororesin, the effect of suppressing the bending of the surface of the belt member is excellent. In addition, according to Example 1, Example 8, and Example 9, it can be seen that if the thickness of the surface layer is 20 μm or more and 50 μm or less, the effect of suppressing the bending of the surface of the belt member is more excellent. In addition, according to Example 1, Example 10, Comparative Example 3, and Comparative Example 4, it can be seen that if the molecular weight of the isocyanate curing agent having isocyanate groups at both ends is 2000 to 4000, the effect of suppressing the bending of the surface of the belt member and the effect of suppressing the sliding sound are more excellent.

[0109] As mentioned above, although embodiment of this invention is described in detail, this invention is not limited to the said embodiment, Various changes can be made within the range which does not deviate from the summary of this invention.

[0110] Description of Reference Numerals

[0111] 10: belt component; 12: base layer; 14: surface layer.

Claims

1. A belt member for an electrophotographic device, wherein: The belt member for an electrophotographic apparatus comprises a cylindrical base layer and a surface layer formed on an outer peripheral surface of the base layer. The base layer contains at least one of polyimide and polyamide-imide, The surface layer is constituted of a cured product of a resin composition comprising a fluororesin having a hydroxyl group, an isocyanate curing agent, a fluorine-based surfactant, and a silane coupling agent having an amino group or an isocyanate group. The isocyanate curing agent has isocyanate groups at both ends and has a molecular weight of 600 g / mol or more and 4000 g / mol or less. The isocyanate curing agent is 10 parts by mass to 30 parts by mass, the fluorine-based surfactant is 5 parts by mass to 10 parts by mass, and the silane coupling agent is 1.0 parts by mass to 5 parts by mass, relative to 100 parts by mass of the fluororesin.

2. A belt member for an electrophotographic device, wherein: The belt member for an electrophotographic apparatus comprises a cylindrical base layer and a surface layer formed on an outer peripheral surface of the base layer. The base layer contains at least one of polyimide and polyamide-imide, The surface layer is constituted of a cured product of a resin composition comprising a fluororesin having a hydroxyl group, an isocyanate curing agent, a fluorine-based surfactant, and a silane coupling agent having an amino group or an isocyanate group. The isocyanate curing agent has an isocyanate group at one end, The isocyanate curing agent is 5 parts by mass to 18 parts by mass, the fluorine-based surfactant is 5 parts by mass to 10 parts by mass, and the silane coupling agent is 1.0 parts by mass to 5 parts by mass, relative to 100 parts by mass of the fluororesin.

3. The belt member for an electrophotographic apparatus according to claim 1 or 2, wherein The fluorine content of the fluorine-based surfactant is 10 mass % or more and 30 mass % or less.

4. The belt member for an electrophotographic apparatus according to any one of claims 1 to 3, wherein The dynamic friction coefficient and the static friction coefficient after 500 wear tests were 0.5 or less.

5. The belt member for an electrophotographic apparatus according to any one of claims 1 to 4, wherein The fluorine content of the fluorine-based surfactant is 10% by mass or more and 30% by mass or less, The dynamic friction coefficient and the static friction coefficient after 500 wear tests were 0.5 or less.

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