JP2010066305A - Resin composition for endless belt of electrophotographic apparatus and endless belt for electrophotographic apparatus using the composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition for an endless belt of an electrophotographic apparatus, wherein the belt is flexible and excellent picture quality is obtained. <P>SOLUTION: The composition for the endless belt of the electrophotographic apparatus contains the following components (A) and (B). The (A)component is a polytetramethylene glycol diglycidyl ether and the (B) component is a cationic photopolymerization initiator. The compounding ratio of the component (B) is in a range from 0.01 to 10 pts.wt. based on 100 pts.wt. of the component (A). The cationic photopolymerization initiator of the (B) component is at least one compound selected from a group consisting of aromatic iodonium salt, aromatic sulfonium salt, aromatic phosphonium salt and ferrocene. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for an endless belt for electrophotographic equipment and an endless belt for electrophotographic equipment using the same, and more specifically, an intermediate transfer belt for electrophotographic equipment such as electrophotographic copying machines, printers, and facsimiles. The present invention relates to a resin composition used as a layer forming material such as a conveyor belt and an endless belt for electrophotographic equipment using the same.

In general, in electrophotographic equipment adopting electrophotographic technology such as full color LBP (laser beam printer) and full color PPC (plain paper copier), for applications such as toner image transfer, paper transfer conveyance, and photoreceptor substrate, Endless belts (seamless belts) are frequently used. As such an endless belt, for example, a belt using a semiconductive polyamideimide film in which a conductive carbon black is contained in a polyamideimide resin as an intermediate transfer belt has been proposed (for example, Patent Document 1, Patent Document 1). 2).
Japanese Patent No. 3218199 JP 2001-354854 A

  However, the intermediate transfer belt using the polyamide-imide resin described in Patent Documents 1 and 2 has a rigid molecular structure, and has high rigidity and poor flexibility. It is hard to deform along. Therefore, it is difficult for the toner on the intermediate transfer belt to follow the irregularities on the surface of the paper, and the transfer efficiency of the toner onto the paper is poor and the image quality is poor. In particular, the worse the paper (recycled paper or the like), the greater the unevenness of the surface of the paper, and the tendency for the image quality to be inferior.

  The present invention has been made in view of such circumstances, and provides a resin composition for an endless belt of an electrophotographic apparatus and an endless belt for an electrophotographic apparatus using the same, which is flexible and can obtain excellent image quality. Is the purpose.

In order to achieve the above object, the first gist of the present invention is a resin composition for an endless belt of an electrophotographic apparatus containing the following components (A) and (B).
(A) Polytetramethylene glycol diglycidyl ether.
(B) Photocationic polymerization initiator.

The present invention also provides an endless belt for an electrophotographic apparatus in which a surface layer is formed on the outer periphery of a base layer directly or via another layer, and at least one layer excluding the base layer includes the following (A) and (B The second gist is an endless belt for an electrophotographic apparatus comprising an ultraviolet cured product of a resin composition containing a component.
(A) Polytetramethylene glycol diglycidyl ether.
(B) Photocationic polymerization initiator.

  That is, the inventors of the present invention have made extensive studies to solve the above problems, and in the course of the research, a resin composition containing polytetramethylene glycol diglycidyl ether and a photocationic polymerization initiator is used as an electrophotographic apparatus. Recalling that it is used for endless belt applications. The polytetramethylene glycol diglycidyl ether is an epoxy compound having a polyoxytetramethylene structure in the main chain and exhibits high elasticity like rubber. Therefore, when the resin composition is used as a layer forming material other than the base layer, such as an intermediate layer (elastic layer) or a surface layer of an endless belt for electrophotographic equipment, the resin composition is excellent in flexibility. As a result, the endless belt such as the intermediate transfer belt is deformed along the unevenness of the surface of the paper, so that the transfer efficiency of the toner to the paper is improved and excellent image quality can be obtained. The present invention has been reached.

  Thus, the resin composition for an endless belt of the electrophotographic apparatus of the present invention contains polytetramethylene glycol diglycidyl ether and a photocationic polymerization initiator. The polytetramethylene glycol diglycidyl ether is an epoxy compound having a polyoxytetramethylene structure in the main chain and exhibits high elasticity like rubber. Therefore, when the resin composition is used as a layer forming material other than the base layer, such as an intermediate layer (elastic layer) or a surface layer of an endless belt for electrophotographic equipment, the resin composition is excellent in flexibility. Since the intermediate transfer belt is deformed along the irregularities on the surface of the paper, the transfer efficiency of the toner to the paper is improved, and excellent image quality can be obtained. Therefore, it is possible to obtain an excellent image quality even when using rough paper having large irregularities on the surface of the paper. Moreover, since the above-mentioned resin composition is cured by ultraviolet irradiation, a drying step after applying the resin composition becomes unnecessary, and an endless structure having a constituent layer (intermediate layer, surface layer) with a high crosslinking rate in a short time. The belt can be manufactured. Furthermore, since a drying step is not necessary, adverse effects on belt performance due to variations in drying conditions can be eliminated.

  Further, when the blending ratio of the cationic photopolymerization initiator is in the range of 0.01 to 10 parts by weight with respect to 100 parts by weight of the polytetramethylene glycol diglycidyl ether, crosslinking by ultraviolet irradiation is sufficiently achieved. .

  Furthermore, when the photocationic polymerization initiator is at least one selected from the group consisting of aromatic iodonium salts, aromatic sulfonium salts, aromatic phosphonium salts, and ferrocene, cations are easily generated by irradiation with ultraviolet rays. The terminal ethylene oxide of tetramethylene glycol diglycidyl ether is ring-opened so that the polymerization can be performed satisfactorily.

  Next, embodiments of the present invention will be described in detail.

  The resin composition for an endless belt of the electrophotographic apparatus of the present invention (hereinafter abbreviated as “resin composition”) comprises polytetramethylene glycol diglycidyl ether (component A) and a photocationic polymerization initiator (component B). Can be obtained.

  The polytetramethylene glycol diglycidyl ether (component A) used in the resin composition preferably has a number average molecular weight (Mn) in the range of 130 to 6000, particularly preferably a number average molecular weight (Mn) of 400 to 3000. It is a range. That is, if the number average molecular weight (Mn) of the A component is too small, the hardness is difficult to decrease and the flexibility of the endless belt is difficult to obtain. Conversely, if the number average molecular weight (Mn) of the A component is too large, This is because the processability is likely to deteriorate due to the high viscosity or wax state.

  Next, as a photocationic polymerization initiator (component B) used together with the polytetramethylene glycol diglycidyl ether (component A), a cation is generated by ultraviolet irradiation, and the polytetramethylene glycol diglycidyl ether (component A) is used. Those having the action of initiating polymerization of are used, and for example, aromatic iodonium salts, aromatic sulfonium salts, aromatic phosphonium salts, ferrocene and the like are preferable. These may be used alone or in combination of two or more.

  Examples of the aromatic 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 hexafluoroantimonate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium tetrafluoroborate, diphenyliodonium hexafluorophosphate, diphenyliodonium Hexafluoroantimonate, diphenyliodonium tetrafluoroborate, and the like. These may be used alone or in combination of two or more.

  Examples of the aromatic 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. These may be used alone or in combination of two or more.

  Examples of the aromatic phosphonium salt include tetraphenylphosphonium hexafluorophosphate, tetraphenylphosphonium hexafluoroantimonate, and tetraphenylphosphonium tetrafluoroborate. These may be used alone or in combination of two or more.

Further, as the ferrocene, for example, eta ⁵ - cyclopentadienyl eta ⁵ - cumenyl - iron (II) hexafluorophosphate, eta ⁵ - cyclopentadienyl eta ⁵ - cumenyl - iron (II) hexafluoroantimonate sulfonates, eta ⁵ - cyclopentadienyl eta ⁵ - cumenyl - iron (II) tetrafluoroborate and the like. These may be used alone or in combination of two or more.

  The blending ratio of the photocationic polymerization initiator (component B) is 0.01 to 10 parts with respect to 100 parts by weight of the polytetramethylene glycol diglycidyl ether (component A) (hereinafter abbreviated as “part”). A range is preferable, and a range of 0.1 to 5 parts is particularly preferable. That is, if the blending ratio of the B component is too small, crosslinking by ultraviolet irradiation is not sufficiently performed. Conversely, if the blending ratio of the B component is too large, the B component may bleed.

  The resin composition of the present invention includes carbon black, graphite, potassium titanate, iron oxide, ions in addition to the polytetramethylene glycol diglycidyl ether (component A) and the photocationic polymerization initiator (component B). Conductive agents such as conductive agents (quaternary ammonium salts, borates, surfactants, etc.), fillers, coloring agents, curing agents, curing accelerators, etc. may be added as necessary. Absent. And the resin composition of this invention can be prepared, for example by mixing each said component with the stirrer etc. which have a stirring blade.

  The resin composition of the present invention thus obtained is used as a layer forming material for endless belts (seamless belts) such as intermediate transfer belts and conveying belts in electrophotographic apparatuses such as electrophotographic copying machines, printers, and facsimiles. Can do. The resin composition of the present invention is suitably used as a layer other than the base layer of an endless belt for electrophotographic equipment, for example, an intermediate layer material and a surface layer material. That is, the base layer of the endless belt is required to have a certain degree of rigidity. However, when the base layer is formed using the resin composition of the present invention, the rigidity required for the endless belt cannot be obtained because of the flexibility. Therefore, the resin composition of the present invention cannot be used as a base layer material for an endless belt for electrophotographic equipment.

  As an endless belt for electrophotographic equipment of the present invention (hereinafter abbreviated as “endless belt”), for example, an intermediate layer 2 is formed on the outer peripheral surface of a base layer (base layer) 1 as shown in FIG. One having a three-layer structure in which a surface layer 3 is formed on the outer peripheral surface is exemplified. And in this invention, it is the biggest characteristics that layers (intermediate layer 2, surface layer 3) other than the said base layer 1 consist of the ultraviolet curing body of the resin composition containing the above-mentioned A component and B component. .

  Examples of the main component of the material (base layer material) for forming the base layer 1 of the endless belt according to the present invention include polyamideimide (PAI) resin, polyethersulfone (PES) resin, fluorine-based resin, and polyimide resin. These may be used alone or in combination of two or more. Among these, PAI resin is preferable in that it exhibits flex resistance and uniform electrical resistance.

  The PAI resin can be produced, for example, by an acid chloride method, an isocyanate method, or the like.

  Examples of the acid component used for the production of the PAI resin include trimellitic acid and its anhydride or acid chloride, as well as benzene-1,2,4,5-tetracarboxylic acid (pyromellitic acid), biphenyltetracarboxylic acid. , Biphenyl sulfone tetracarboxylic acid, benzophenone tetracarboxylic acid, biphenyl ether tetracarboxylic acid, ethylene glycol bis trimellitate, propylene glycol bis trimellitate, etc., and their anhydrides, oxalic acid, adipic acid, malonic acid, sebatin Aliphatic dicarboxylic acids such as acid, azelaic acid, dodecanedicarboxylic acid, dicarboxypolybutadiene, dicarboxypoly (acrylonitrile-butadiene), dicarboxypoly (styrene-butadiene), 1,4-cyclohexanedicarboxylic acid , 1,3-cyclohexanedicarboxylic acid, 4,4'-dicyclohexylmethanedicarboxylic acid, dimer acid and other alicyclic dicarboxylic acids, terephthalic acid, isophthalic acid, diphenylsulfone dicarboxylic acid, diphenyl ether dicarboxylic acid, naphthalenedicarboxylic acid and other fragrances Group dicarboxylic acids. These may be used alone or in combination of two or more. Among these, trimellitic anhydride is preferably used in terms of reactivity, heat resistance, solubility, and the like.

  Examples of the diamine or diisocyanate used in the production of the PAI resin include aliphatic diamines such as ethylenediamine, propylenediamine, and hexamethylenediamine, and diisocyanates thereof, 1,4-cyclohexanediamine, 1,3-cyclohexanediamine, and isophorone. Diamines, alicyclic diamines such as 4,4'-dicyclohexylmethanediamine, and diisocyanates thereof, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4-diaminodiphenyl ether, 4,4 ' -Aromatic diamines such as diaminodiphenylsulfone, benzidine, o-tolidine, 2,4-tolylenediamine, 2,6-tolylenediamine, xylylenediamine, and their diisocyanates And the like. These may be used alone or in combination of two or more. Of these, 4,4'-diaminodiphenylmethane and its diisocyanate, 2,4-tolylenediamine and its diisocyanate, o-tolidine and its diisocyanate, isophoronediamine, in terms of heat resistance, mechanical properties, solubility, etc. And its diisocyanate are preferably used.

  The PAI resin preferably has a number average molecular weight (Mn) in the range of 10,000 to 50,000, particularly preferably Mn in the range of 15,000 to 40,000. That is, if the Mn of the PAI resin is too small, the tear strength is lowered and the durability is deteriorated. Conversely, if the Mn of the PAI resin is too large, the solution viscosity becomes high and the workability tends to deteriorate. .

  As the base layer material, a conductive filler may be used together with the main components such as the PAI resin.

Examples of the conductive filler include conductive powders such as carbon black and graphite, metal powders such as aluminum powder and stainless steel powder, conductive zinc oxide (c-ZnO), and conductive titanium oxide (c-TiO ₂ ). , Conductive metal oxides such as conductive iron oxide (c-Fe ₃ O ₄ ) and conductive tin oxide (c-SnO ₂ ), quaternary ammonium salts, phosphate esters, sulfonates, aliphatic polyvalent Examples thereof include ionic conductive agents such as alcohol and aliphatic alcohol sulfate salts. These may be used alone or in combination of two or more.

  Further, the base layer material may contain an organic solvent such as DMF, DMAC, toluene, acetone, NMP, or a filler, if necessary, together with the above components.

  For the base layer material, for example, a PAI resin, a conductive filler, an organic solvent, and a filler are appropriately blended as necessary and mixed with a stirring blade, and then a ring mill, a ball mill, a sand mill or the like is used. And then dispersed.

  Next, a material for forming the intermediate layer 2 (material for the intermediate layer) formed on the outer peripheral surface of the base layer 1 will be described. When the said intermediate | middle layer 2 consists of an ultraviolet curing body of the resin composition containing the above-mentioned A component and B component, the above-mentioned resin composition of this invention is used as a material for intermediate | middle layers. Examples of the intermediate layer material other than the resin composition include a thermoplastic resin and a rubber elastic layer material.

  Examples of the thermoplastic resin include fluorine resins such as polyvinylidene fluoride (PVDF), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), and ethylene-tetrafluoroethylene copolymer (ETFE), and polyethylene-based resins. Resin, polystyrene resin, acrylic resin, polycarbonate (PC) resin, polyamide resin, EVA (ethylene-vinyl acetate copolymer) resin, EEA (ethylene-ethyl acrylate copolymer) resin, etc. It is done. These may be used alone or in combination of two or more. Among these, it is preferable to use a fluorine-based resin such as PVDF from the viewpoint of excellent flame retardancy.

  Further, as the rubber elastic layer material, for example, a vulcanization accelerator, a solvent, a processing aid, an anti-aging agent and the like can be used together with a rubber material and a vulcanizing agent as necessary. Note that the conductive elastic filler as described above may be blended in the rubber elastic layer material.

  Examples of the rubber material include chlorinated polyethylene rubber (CPE) and chloroprene rubber (CR) from the viewpoint of flame retardancy. Among these, the optimum material is selected according to the electrical characteristics, elasticity, and durability required for each intermediate transfer belt.

  Next, the forming material (surface layer material) of the surface layer 3 formed on the outer peripheral surface of the intermediate layer 2 will be described. When the surface layer 3 is composed of the ultraviolet cured product of the resin composition containing the aforementioned component A and component B, a material for which the surface modifier is added to the resin composition of the present invention is used as the material for the surface layer. Used.

  Examples of the surface modifier include fluorine compounds and silicone oil. These may be used alone or in combination of two or more.

  The blending ratio of the surface modifier is preferably in the range of 0.1 to 20 parts, particularly preferably 0.5 to 10 parts with respect to 100 parts of the polytetramethylene glycol diglycidyl ether (component A). It is a range.

  Examples of the material for the surface layer other than the resin composition include a silicone resin, a fluorine resin, a urethane resin, an acrylic resin, and a polyamide resin. These may be used alone or in combination of two or more. Among these, liquid or solvent-soluble types are preferably used in consideration of normal workability. In addition, for the purpose of preventing dirt, improving the strength of the coating film, or improving the adhesion, a modified resin material may be used, for example, a modified acrylic resin. As this modified acrylic resin, those having the molecular structure of the acrylic resin as a base and modified with other resins or resin components are preferable. For example, a silicone-modified acrylic resin is preferably used.

  Examples of the silicone-modified acrylic resin include a silicone graft acrylic resin. The silicone graft acrylic resin is preferably a resin obtained by graft polymerization of a silicone resin to an acrylic resin (main chain). Specific examples of the silicone-grafted acrylic resin include Saimak US-350 manufactured by Toagosei Co., Ltd.

  In addition, as the material for the surface layer, the resin material is subjected to resin crosslinking using a resin crosslinking agent such as isocyanate resin, amino resin, phenol resin, xylene resin, or a photosensitive monomer or polymer. An ultraviolet curable material mixed with a photopolymerization initiator may be used.

  The surface layer material can be prepared, for example, by appropriately blending a modified acrylic resin and an organic solvent such as DMF, toluene, and acetone and mixing with a stirring blade. In order to form each layer with high accuracy, it is preferable to use different types of organic solvents as materials for forming adjacent layers. That is, it is preferable to use different types of organic solvents for the surface layer material and organic solvents for the intermediate layer material.

  The endless belt of the present invention is not limited to the three-layer structure shown in FIG. 1, and may have a two-layer structure in which the surface layer 3 is directly formed on the surface of the base layer 1, for example. Further, the intermediate layer 2 between the base layer 1 and the surface layer 3 is not limited to one layer, and may be two or more layers. However, at least one layer excluding the base layer 1 needs to be made of an ultraviolet cured product of a resin composition containing the A component and the B component.

  Next, the method for producing the endless belt of the present invention will be specifically described.

(1) An endless belt (see FIG. 1) having a three-layer structure in which an intermediate layer 2 is formed on an outer peripheral surface of a base layer 1 and a surface layer 3 is formed on the outer peripheral surface. The manufacturing method of the endless belt currently formed using the resin composition of.

(Preparation of base layer material)
Prepare a reaction vessel equipped with a stirrer, nitrogen introduction tube, thermometer, and cooling tube, mix a predetermined amount of MDI and acid components such as trimellitic anhydride, N-methyl-2-pyrrolidone (NMP), N , N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAC), γ-butyrolactone, etc. are charged with a polar solvent and stirred for a predetermined time (preferably 1 hour) under a nitrogen stream with a predetermined temperature (preferably Is raised to 130 ° C., reacted at a predetermined temperature (preferably 130 ° C.) for a predetermined time (preferably about 5 hours), and then the reaction is stopped to prepare a solvent for PAI resin. Next, a conductive filler such as carbon black, an organic solvent such as NMP, and a filler are appropriately blended in the solvent of the PAI resin as necessary, and mixed with a stirring blade, followed by a ring mill, a ball mill. The base layer material is prepared by dispersing using a sand mill or the like.

(Preparation of intermediate layer material)
It can be prepared according to the method for producing the resin composition of the present invention described above. That is, together with the polytetramethylene glycol diglycidyl ether (component A) and the cationic photopolymerization initiator (component B), a conductive agent such as carbon black, a filler, a colorant, a curing agent, a curing accelerator, and the like are necessary. The intermediate layer material is prepared by adding them appropriately according to the above and mixing these components with a stirrer having a stirring blade.

(Preparation of surface layer material)
A surface-layer material is prepared by appropriately blending a modified acrylic resin and an organic solvent such as DMF and mixing with a stirring blade.

(Production of endless belt)
First, a mold (cylindrical base) is prepared, and the base layer material is spray coated on the surface to form the base layer 1 on the surface of the mold. This is heated and heated for a predetermined time (preferably 2 hours) from room temperature (25 ° C.) to 250 ° C. Next, the intermediate layer material is spray-coated on the surface of the base layer 1, and an ultraviolet ray irradiator (for example, UB031- manufactured by Igraphic Co., Ltd.) is rotated while the mold is rotated at a predetermined rotational speed (preferably 100 rpm). 2A / BM) or the like to irradiate the coating liquid (interlayer material) with ultraviolet rays to form the intermediate layer 2 made of an ultraviolet cured body of the coating liquid (intermediate layer material). At this time, the distance between the ultraviolet lamp (for example, mercury lamp type) of the ultraviolet irradiator and the intermediate layer 2 is usually 100 to 300 mm, preferably 200 mm, and the ultraviolet irradiation time is usually 30 seconds to 30 mm. Minutes, preferably about 1 minute. Subsequently, the surface layer material is spray coated on the surface of the intermediate layer 2 and dried at 100 to 300 ° C. for 0.5 to 6 hours. Thereafter, by blowing air between the base layer 1 and the mold (cylindrical base body), the cylindrical base body is extracted, an intermediate layer (elastic layer) 2 is formed on the surface of the base layer 1, and a surface layer is formed on the outer peripheral surface thereof. An endless belt (see FIG. 1) having a three-layer structure in which 3 is formed is produced. In addition, the formation method of the said surface layer 3 is not limited to the said spray coating method, For example, you may form by the dipping method etc.

(2) An endless belt (see FIG. 1) having a three-layer structure in which the intermediate layer 2 is formed on the outer peripheral surface of the base layer 1 and the surface layer 3 is formed on the outer peripheral surface. The manufacturing method of the endless belt currently formed using the resin composition.

(Preparation of base layer material)
A base layer material is prepared according to the method for producing an endless belt described in (1) above.

(Preparation of intermediate layer material)
Along with rubber materials such as chloroprene rubber (CR) and vulcanizing agents, vulcanization accelerators, solvents, processing aids, anti-aging agents, conductive agents, etc. are blended as necessary, and these are mixed using a Banbury mixer. An intermediate layer material is prepared by kneading.

(Preparation of surface layer material)
It can be prepared according to the method for producing the resin composition of the present invention described above. That is, in addition to the polytetramethylene glycol diglycidyl ether (component A) and the photocationic polymerization initiator (component B), a surface modifier such as a fluorine-based compound or silicone oil is blended, and if necessary, carbon black Conductive agents such as fillers, colorants, curing agents, curing accelerators, etc. are appropriately added, and these components are mixed with a stirrer having a stirring blade to obtain a surface layer material (coating liquid). Prepare.

(Production of endless belt)
The base layer 1 is formed according to the method for producing an endless belt (1). That is, first, a mold (cylindrical base body) is prepared, and the base layer material is spray coated on the surface to form the base layer 1 on the surface of the mold. This is heated and heated for a predetermined time (preferably 2 hours) from room temperature (25 ° C.) to 250 ° C. Next, the intermediate layer material is spray coated on the surface of the base layer 1 and dried at 100 to 300 ° C. for 0.5 to 6 hours. Next, the surface layer material is spray-coated on the surface of the intermediate layer 2, and an ultraviolet ray irradiator (for example, UB031- manufactured by Eye Graphic Co., Ltd.) is rotated while the mold is rotated at a predetermined rotation speed (preferably 100 rpm). 2A / BM) or the like to irradiate the surface layer material (coating liquid) with ultraviolet rays to form the surface layer 3 made of an ultraviolet cured body of the coating liquid (surface layer material). At this time, the distance between the ultraviolet lamp (for example, mercury lamp type) of the ultraviolet irradiator and the surface layer 3 is usually 100 to 300 mm, preferably 200 mm, and the ultraviolet irradiation time is usually 30 seconds to 30 minutes. Preferably, it is about 1 minute. Thereafter, by blowing air between the base layer 1 and the mold (cylindrical base body), the cylindrical base body is extracted, an intermediate layer (elastic layer) 2 is formed on the surface of the base layer 1, and a surface layer is formed on the outer peripheral surface thereof. An endless belt (see FIG. 1) having a three-layer structure in which 3 is formed is produced.

(3) An endless belt (see FIG. 1) having a three-layer structure in which the intermediate layer 2 is formed on the outer peripheral surface of the base layer 1 and the surface layer 3 is formed on the outer peripheral surface. However, the manufacturing method of the endless belt currently formed using the resin composition of this invention.

(Preparation of base layer material)
A base layer material is prepared according to the method for producing an endless belt described in (1) above.

(Preparation of intermediate layer material)
An intermediate layer material (resin composition) is prepared in accordance with the process for producing an endless belt described in (1) above.

(Preparation of surface layer material)
A surface layer material (resin composition) is prepared in accordance with the method for producing an endless belt described in (2) above.

(Production of endless belt)
The base layer 1 and the intermediate layer 2 are formed in accordance with the method for producing an endless belt (1). Next, the surface layer material is spray-coated on the surface of the intermediate layer 2, and an ultraviolet ray irradiator (for example, UB031- manufactured by Eye Graphic Co., Ltd.) is rotated while the mold is rotated at a predetermined rotation speed (preferably 100 rpm). 2A / BM) or the like to irradiate the coating liquid (surface layer material) with ultraviolet rays to form the surface layer 3 made of an ultraviolet cured body of the coating liquid (surface layer material). At this time, the distance between the ultraviolet lamp (for example, mercury lamp type) of the ultraviolet irradiator and the surface layer 3 is usually 100 to 300 mm, preferably 200 mm, and the ultraviolet irradiation time is usually 30 seconds to 30 minutes. Preferably, it is about 1 minute. Thereafter, by blowing air between the base layer 1 and the mold (cylindrical base body), the cylindrical base body is extracted, an intermediate layer (elastic layer) 2 is formed on the surface of the base layer 1, and a surface layer is formed on the outer peripheral surface thereof. An endless belt (see FIG. 1) having a three-layer structure in which 3 is formed is produced.

(4) A process for producing an endless belt having a two-layer structure in which a surface layer 3 is directly formed on the outer peripheral surface of a base layer 1, wherein the surface layer 3 is formed using the resin composition of the present invention.

(Preparation of base layer material)
A base layer material is prepared according to the method for producing an endless belt described in (1) above.

(Preparation of surface layer material)
A surface layer material (resin composition) is prepared in accordance with the method for producing an endless belt described in (2) above.

(Production of endless belt)
The base layer 1 is formed according to the method for producing an endless belt (1). Next, the surface layer material is spray-coated on the surface of the base layer 1, and an ultraviolet ray irradiator (for example, UB031-2A manufactured by Eye Graphic Co., Ltd.) is rotated while the mold is rotated at a predetermined rotational speed (preferably 100 rpm). / BM) or the like to irradiate the coating liquid (surface layer material) with ultraviolet rays to form the surface layer 3 made of an ultraviolet cured body of the coating liquid (surface layer material). At this time, the distance between the ultraviolet lamp (for example, mercury lamp type) of the ultraviolet irradiator and the surface layer 3 is usually 100 to 300 mm, preferably 200 mm, and the ultraviolet irradiation time is usually 30 seconds to 30 minutes. Preferably, it is about 1 minute. Thereafter, by blowing air between the base layer 1 and a mold (cylindrical base body) or the like, the cylindrical base body is extracted, and an endless belt having a two-layer structure in which the surface layer 3 is formed on the surface of the base layer 1 is manufactured.

  As described above, when the resin composition of the present invention is used as a layer forming material other than the base layer 1 such as the intermediate layer 2 or the surface layer 3 of the endless belt, when the intermediate layer 2 or the surface layer 3 is formed, There is an advantage that an endless belt can be produced in a short time since such a drying process or a heat treatment is not required.

Whether or not the intermediate layer 2 and the surface layer 3 of the endless belt of the present invention are made of a cured product of the resin composition of the present invention is analyzed by, for example, ¹³ C-NMR, ¹ H-NMR, IR, gas chromatography or the like. This can be confirmed by analysis using an instrument.

  Although the thickness of each layer of the endless belt of the present invention is appropriately set according to the use of the belt, the thickness of the base layer 1 is usually in the range of 30 to 300 μm, and preferably in the range of 50 to 200 μm. The thickness of the intermediate layer 2 is preferably in the range of 30 to 5000 μm, particularly preferably in the range of 50 to 200 μm. The thickness of the surface layer 3 is preferably in the range of 0.1 to 30 μm, particularly preferably in the range of 0.5 to 20 μm. The endless belt of the present invention preferably has an inner peripheral length of 500 to 2500 mm and a width of about 150 to 600 mm. That is, if the size is set within the above range, the size is appropriate for use in an electrophotographic copying machine.

  In the endless belt of the present invention, the elastic modulus of the base layer 1 is preferably in the range of 1000 to 10000 MPa, particularly preferably in the range of 3000 to 8000 MPa, from the viewpoint of durability.

  Next, examples will be described together with comparative examples. However, the present invention is not limited to these examples.

  First, prior to the examples and comparative examples, the following materials were prepared.

[Epoxy compound A (component A)]
Polytetramethylene glycol diglycidyl ether (number average molecular weight: 950) (Epogosei PT, manufactured by Yokkaichi Chemical Co., Ltd.)

[Epoxy compound a]
Polybutadiene epoxide (Daicel Chemical Industries, Epolide PB3600)
[Epoxy compound b]
Polyethylene glycol diglycidyl ether (manufactured by Nagase ChemteX Corporation, EX-931)
[Epoxy compound c]
(3,4-epoxycyclohexenyl) methyl-3 ', 4'-epoxycyclohexene carboxylate (Daicel Chemical Industries, Celoxide 2021P)
[Epoxy compound d]
ε-caprolactone-modified 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate (Daicel Chemical Industries, Celoxide 2081)

[Photocationic polymerization initiator A (component B)]
Aromatic sulfonium salt (manufactured by San Apro, CPI-100P)
[Photocationic polymerization initiator B (component B)]
Aromatic iodonium salt (Ciba Japan, IRGACURE250)

[Surface modifier]
Epoxy-modified silicone oil (manufactured by Chisso Corporation, FM-0521, Mn: 5000, one end type)

  Next, a resin composition was prepared as follows using each of the above materials.

[Preparation of Resin Compositions A to C, a to d]
The components shown in Table 1 below were blended in the proportions shown in the same table, and these were mixed with a stirrer having stirring blades to prepare a resin composition.

  Using the thus obtained resin compositions A to C and a to d, each characteristic was evaluated according to the following criteria. These results are also shown in Table 1 above.

[Hardness (Martens hardness)]
Each resin composition (used for the coating layer of the endless belt) is bar-coated on the release polyester sheet so that the film thickness is constant, and an ultraviolet irradiator (UB031-2A / BM, manufactured by Eye Graphic Co., Ltd.) is used. By irradiating with ultraviolet rays, a resin sheet (thickness 30 μm) having the same form as the coating layer of the endless belt was obtained. The distance between the sheet and the ultraviolet irradiator was 200 mm, and the irradiation time was 1 minute (integrated light amount: 120 mW / cm ² ). The Martens hardness of the surface of the obtained sheet (N / mm ^2), was measured using a Fischerscope H100 (manufactured by Fischer Co.). The indentation condition at the time of the measurement was to push in with a load up to 2 mN over 5 seconds, and then release the load up to 0 mN over 5 seconds.

[Rebound resilience]
Each resin composition is poured into a cylindrical glass mold having a straight diameter of 28 mm and a height of 12 mm, and the resin composition is cured by irradiating ultraviolet rays from the outside of the mold, and then demolded. As a result, a measurement sample (sample) was obtained. At the time of the ultraviolet irradiation, the distance between the ultraviolet lamp (mercury lamp type) of the ultraviolet irradiator (UB031-2A / BM, manufactured by Eye Graphic Co., Ltd.) and the resin composition in the mold is 200 mm, and irradiation is performed for 3 minutes ( UV accumulated light amount 360 mW / cm ²⁾ and the. And about the said sample, the resilience elastic modulus (%) was measured according to JIS-K-6255. A rebound resilience value of 60% or more indicates excellent elasticity.

  From the results of Table 1, the resin compositions A to C had low hardness and high rebound resilience. In the resin compositions A to C, the same excellent effects as the resin compositions A to C were also obtained when the proportion of the photocationic polymerization initiator was changed to 0.01 parts and 10 parts.

  On the other hand, since the resin compositions a to d have high hardness and low rebound resilience, the transfer efficiency of the toner to paper deteriorates even when used for the intermediate layer or surface layer of the intermediate transfer belt. Can not get good image quality.

  Next, an endless belt was produced using the resin composition.

[Example 1]
(Preparation of base layer material)
In a reaction vessel equipped with a stirrer, a nitrogen introducing tube, a thermometer, and a cooling tube, 50 parts of MDI (manufactured by Nippon Polyurethane Industry Co., Ltd., Millionate MT, Mn: 250.06), 38 parts of trimellitic anhydride, and NMP solvent 164 The mixture was heated to 130 ° C. over 1 hour with stirring under a nitrogen stream, reacted for about 5 hours at 130 ° C., and then the reaction was stopped, and a PAI-NMP solution (PAI: 30% by weight) was added. Prepared. Next, 3 parts of carbon black (manufactured by Cabot Japan, Show Black N220) was mixed with this PAI-NMP solution, mixed with a stirring blade, and then dispersed with a ball mill to prepare a base layer material.

(Preparation of intermediate layer material)
The previously prepared resin composition A (see Table 1) was used.

(Preparation of surface layer material)
100 parts of silicone graft acrylic resin (Saimak US-350, manufactured by Toagosei Co., Ltd.) and 500 parts of toluene solvent were blended and mixed with a stirring blade to prepare a surface layer material.

(Production of endless belt)
First, a mold (cylindrical base body) was prepared, and the base layer material was spray coated on the surface to form a base layer on the surface of the mold. This was heated and heated for 2 hours from normal temperature (25 ° C.) to 250 ° C. Next, the intermediate layer material is spray-coated on the surface of the base layer, and a coating solution (UB031-2A / BM manufactured by Eye Graphic Co., Ltd.) is used while rotating the mold at 100 rpm. The intermediate layer material was irradiated with ultraviolet rays to form an intermediate layer made of an ultraviolet cured material of the coating liquid (interlayer material). At this time, the distance between the UV lamp (mercury lamp type) of the UV irradiator and the intermediate layer was 200 mm, and the UV irradiation time was 1 minute (integrated light quantity 120 mW / cm ² ). Subsequently, the surface layer material was spray-coated on the surface of the intermediate layer, and this was dried at 120 ° C. for 1 hour. After that, by blowing air between the base layer and the mold (cylindrical base body), the cylindrical base body is extracted, and an intermediate layer (elastic layer) (thickness: 100 μm) is formed on the surface of the base layer (thickness: 100 μm). Further, an endless belt (see FIG. 1) having a three-layer structure in which a surface layer (thickness: 5 μm) was formed on the outer peripheral surface was produced.

[Example 2, Comparative Examples 1 to 4]
As the intermediate layer material, the resin composition shown in Table 2 below was used in place of the resin composition A of Example 1. Then, an endless belt was produced in the same manner as in Example 1 except that this intermediate layer material was used.

Example 3
(Preparation of base layer material)
A base layer material was prepared in the same manner as the base layer material of Example 1.

(Preparation of intermediate layer material)
100 parts of chloroprene rubber (Denka Chloroprene A-30, manufactured by Denki Kagaku Kogyo Co., Ltd.), 1.5 parts of vulcanizing agent (manufactured by Sanshin Chemical Industry Co., Ltd., Sunseller 22C), carbon black (Ketjen Black International Co., Ltd., Ketjen) EC) 2 parts were kneaded and then dissolved in MEK solvent to prepare an intermediate layer material.

(Preparation of surface material)
The previously prepared resin composition C (see Table 1) was used.

(Production of endless belt)
First, a mold (cylindrical base body) was prepared, and the base layer material was spray coated on the surface to form a base layer on the surface of the mold. This was heated and heated for 2 hours from normal temperature (25 ° C.) to 250 ° C. Next, the intermediate layer material was spray coated on the surface of the base layer, and this was dried at 120 ° C. for 1 hour. Next, the surface layer material is spray coated on the surface of the intermediate layer, and the coating liquid (UB031-2A / BM manufactured by Eye Graphic Co., Ltd.) is used while rotating the mold at 100 rpm. Surface layer material) was irradiated with ultraviolet rays to form a surface layer made of an ultraviolet cured body of the coating liquid (surface layer material). In this case, the above-described ultraviolet ray irradiation device of the ultraviolet lamps (mercury lamp type), the distance between the surface layer is at 200 mm, the irradiation time of ultraviolet rays was 1 minute (integrated quantity of light 120 mW / cm ^2). After that, by blowing air between the base layer and the mold (cylindrical base body), the cylindrical base body is extracted, and an intermediate layer (elastic layer) (thickness: 100 μm) is formed on the surface of the base layer (thickness: 100 μm). Further, an endless belt (see FIG. 1) having a three-layer structure in which a surface layer (thickness: 5 μm) was formed on the outer peripheral surface was produced.

Example 4
(Preparation of base layer material)
A base layer material was prepared in the same manner as the base layer material of Example 1.

(Preparation of surface material)
The previously prepared resin composition C (see Table 1) was used.

(Production of endless belt)
First, a mold (cylindrical base body) was prepared, and the base layer material was spray coated on the surface to form a base layer on the surface of the mold. This was heated and heated for 2 hours from normal temperature (25 ° C.) to 250 ° C. Next, the surface layer material is spray-coated on the surface of the base layer, and the coating liquid (surface layer) is applied using an ultraviolet irradiation machine (UB031-2A / BM manufactured by Eye Graphic Co., Ltd.) while rotating the mold at 100 rpm. The surface layer made of an ultraviolet cured material of the coating liquid (surface layer material) was formed. At this time, the distance between the ultraviolet lamp (mercury lamp type) of the ultraviolet irradiator and the surface layer was 200 mm, and the ultraviolet irradiation time was 1 minute (integrated light amount 120 mW / cm ² ). Thereafter, air is blown between the base layer and the mold (cylindrical base body) to extract the cylindrical base body, and a surface layer (thickness: 20 μm) is formed on the surface of the base layer (thickness: 100 μm). An endless belt was prepared.

  Using the endless belts of Examples and Comparative Examples thus obtained, each characteristic was evaluated according to the following criteria. These results are also shown in Table 2 above.

[Bench durability test]
Two metal rollers having a diameter of 13 mm were prepared, and one metal roller was fixed on the table in a state where an endless belt (width 150 mm) was stretched between the two metal rollers. Next, the other metal roller that is not fixed to the table is placed at the end of the table, and 2 kg of weight is suspended from both ends of the metal roller (total load 4 kg), and the laboratory environment (25 ° C × 40%), the endless belt was rotated. Then, the cumulative number of revolutions until a crack was confirmed on the endless belt was measured.

[Uniformity of electrical resistance]
Volume electrical resistivity at eight locations on the inner peripheral side of the endless belt equally divided in the circumferential direction was measured according to JIS K6911, and the variation between the maximum value and the minimum value was displayed in digits. The applied voltage was 10V. In the evaluation, “◯” indicates that the variation is 0.5 digits or less, “△” indicates that the variation exceeds 0.5 digits and is 1 digit or less, and “X” indicates that the variation exceeds 1 digit.

[Real machine image evaluation]
Each endless belt was attached to a full-color PPC, and 1000 images were evaluated for evaluation, and the presence or absence of image defects such as defective cleaning and transfer to the endless belt was evaluated. In the evaluation, “◯” indicates no image defect and “x” indicates an image defect.

  From the results of Table 2 above, all the products of the examples were excellent in durability and uniformity of electrical resistance, and image quality was improved because there was no image defect. As described above, in the resin compositions A to C, when the resin composition in which the blending ratio of the photocationic polymerization initiator was changed to 0.01 part and 10 parts was used, the same excellent as the example product The effect was obtained.

  On the other hand, the products of Comparative Examples 1 to 4 were remarkably inferior in durability, inferior in electrical resistance uniformity, and inferior in image quality.

  The resin composition of the present invention is used as a layer forming material other than a base layer, such as an intermediate layer and a surface layer, in an endless belt for an electrophotographic apparatus such as an intermediate transfer belt and a conveyance belt.

It is a fragmentary sectional view which shows an example of the endless belt for electrophotographic apparatuses of this invention.

Explanation of symbols

1 base layer 2 intermediate layer 3 surface layer

Claims (7)

A resin composition for an endless belt of an electrophotographic apparatus, comprising the following components (A) and (B):
(A) Polytetramethylene glycol diglycidyl ether.
(B) Photocationic polymerization initiator.   The resin composition for an endless belt for an electrophotographic apparatus according to claim 1, wherein the blending ratio of the component (B) is in the range of 0.01 to 10 parts by weight with respect to 100 parts by weight of the component (A).   3. The electrophotography according to claim 1, wherein the photocationic polymerization initiator as the component (B) is at least one selected from the group consisting of aromatic iodonium salts, aromatic sulfonium salts, aromatic phosphonium salts, and ferrocene. Resin composition for endless belts of equipment. An endless belt for an electrophotographic apparatus having a surface layer formed on the outer periphery of a base layer directly or via another layer, wherein at least one layer excluding the base layer contains the following components (A) and (B): An endless belt for electrophotographic equipment, comprising an ultraviolet cured product of the composition.
(A) Polytetramethylene glycol diglycidyl ether.
(B) Photocationic polymerization initiator.   A base layer, an intermediate layer formed on the outer peripheral surface of the base layer, and a surface layer formed on the outer peripheral surface of the intermediate layer, wherein at least one of the intermediate layer and the surface layer contains the components (A) and (B) The endless belt for an electrophotographic apparatus according to claim 4, comprising an ultraviolet-cured product of the resin composition.   The endless belt for an electrophotographic apparatus according to claim 4 or 5, wherein a blending ratio of the component (B) is in a range of 0.01 to 10 parts by weight with respect to 100 parts by weight of the component (A).   7. The cationic photopolymerization initiator as the component (B) is at least one selected from the group consisting of aromatic iodonium salts, aromatic sulfonium salts, aromatic phosphonium salts, and ferrocenes. An endless belt for an electrophotographic apparatus according to Item.

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