JP3677999B2 - Endless belt for electrophotographic apparatus and manufacturing method thereof - Google Patents

Description

【００２９】
下記のシアノ化合物０．５重量部、
【００３０】
【化２】

【００３１】
２，６−ジターシャリブチルヒドロキシトルエン（ＢＨＴ）８重量部および、バインダーとして、ポリカーボネート樹脂（三菱化学（株）製、「ノバレックス」（商標）７０３０Ａ）１００重量部を１，４−ジオキサン１０００重量部に溶解させた液をフィルムアプリケーターにより塗布し、乾燥後の膜厚が１７μｍになるように電荷輸送層を設けた。
一方、断面が図２（Ｂ）に示すような３ｍｍ×１ｍｍの直方体で、１ｍｍ×０．２ｍｍの凹部を平行して２本有する形状の型窪を有する型板にシリコンゴム（東レダウコーニングシリコーン（株）製ＳＥ９１５５）を充填して硬化し、細帯状のガイド用リブを成形した。
その接着面に前記と同じシリコンゴムを塗布して凹部に充填すると共に接着面に塗布した。
【００３２】
これを前記感光体シートの両側縁に沿って添着した。そのまま静置したところ１０分後には接着剤の硬化が進行し、少しの力ではずれなくなった。
ガイド用リブを接合した感光体シートはその両端縁を超音波シール機で融着して無端ベルト状感光体を得た。
これを市販のカラー電子複写機に充填して６０，０００枚の複写試験を行ったが色ずれは生じなかった。
【００３３】
比較例１
ガイド用リブの接合面に凹部を形成することなく平坦面とした外は実施例１と全く同じ操作を行った。
その結果、ガイド用リブを基材に添着して２０分後では、まだ接着剤の硬化が不充分で僅かな力で剥離、ずれが生じた。ずれが生じない程度に硬化するまでに３５分間を要した。
【図面の簡単な説明】
【図１】本発明無端ベルトの実施例を示す一部切欠き斜視図。
【図２】本発明に使用するガイド用リブの各種例を示す縦断面図。
【図３】本発明に使用するガイド用リブの他の例を示す縦断面図。
【図４】接着剤を塗布したときのガイド用リブの縦断面図。
【図５】無端ベルト状感光体を示す側面図。
【図６】中間転写ベルトを示す側面図。
【図７】無端ベルトを駆動するロールを示す一部切欠き斜視図。
【図８】無端ベルトを駆動するロールの他の例を示す１部切欠側面図。
【符号の説明】
１ 無端ベルト
２ 基材
３ ガイド用リブ
３ａ 凸部
３ｂ 凹部
４ 両面感圧接着テープ
５ 接着剤
２０ 無端ベルト状電子写真感光体
３０ 中間転写ベルト
３２，３５ ロール[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endless belt used in an electrophotographic apparatus and a manufacturing method thereof. More particularly, the present invention relates to an endless belt for an electrophotographic apparatus that has a rib for preventing meandering and can stably run for a long period of time, and a method for manufacturing the endless belt with high productivity.
[0002]
[Prior art]
In recent years, electrophotographic image forming methods have been widely used in copying machines, printers, and the like because high-quality images can be obtained immediately. As the core photoreceptor, an endless belt-shaped electrophotographic photoreceptor is widely used because of its flexible properties and a high degree of freedom in arrangement in the apparatus.
The endless belt-like photoreceptor 20 is formed by laminating a metal layer on a synthetic resin film and cutting a photoreceptor sheet on which a photoreceptor layer such as a charge generation layer and a charge transport layer is formed to a predetermined size. As shown in FIG. 5, both ends thereof are fused and formed in an annular shape using an ultrasonic sealing machine or the like, and used as an image forming mechanism. Reference numeral 21 denotes a charger, 22 denotes an exposure optical system, 23 denotes a developing unit, 24 denotes a cleaner, 25 denotes a transfer charger, and 26 denotes a transfer sheet.
[0003]
In the electrophotographic apparatus, an intermediate transfer belt 30 is used as shown in FIG. The intermediate transfer belt 30 temporarily transfers the image developed by the developing unit 23 onto the photosensitive drum 20 a onto the intermediate transfer belt 30 and transfers it again to the paper 26.
Thus, the endless belt-like electrophotographic photosensitive member 20 or the intermediate transfer belt 30 has a problem that meandering occurs during running.
For this reason, as shown in FIG. 7, the endless belt such as the endless belt-shaped photoconductor 20 is joined with a rib material made of a rubber-like flexible material along the side edge of the back surface of the annular base material 20 for guiding. The rib 31 is formed, and the rib 31 is fitted into the groove 33 of the roll 32 to travel, thereby preventing meandering.
[0004]
However, since the guide rib 31 is repeatedly bent every time it goes around the outer periphery of the drive roll 32, a soft material is used. In order to increase productivity, the guide rib 31 is formed on the side edge of the substrate with the soft material. A technique for efficiently forming the rib-like body is required.
Conventionally, as a rib forming method, on the back surface of a film-like substrate, a mold plate in which long groove-shaped depressions penetrating the front and back are overlapped, and the long groove is filled with silicon rubber or the like, and the rib-shaped body is directly on the film-like body. The method of forming is taken.
[0005]
However, in the case of directly forming the rib-like body, it is necessary to fix the template so that it does not move until the filled rib material is cured, and the production efficiency cannot be increased.
In addition, a method of separately forming a rib body and joining the formed rib body to a film-like body using a double-sided pressure-sensitive adhesive tape or an adhesive is also employed.
However, when a double-sided pressure-sensitive adhesive tape is used, there is a problem that the adhesive strength is likely to be lowered by long-term use.
[0006]
In addition, when bonding using a reaction curable adhesive, for example, a room temperature curable silicone rubber adhesive, it is necessary to increase the thickness of the adhesive layer in order to obtain adhesive strength. If the thickness is increased, the progress of the curing reaction will be slow, and it will be necessary to hold the initial adhesive strength until it reaches the specified value so that no deviation will occur. There was a problem of low production efficiency.
[0007]
[Problems to be solved by the invention]
The present invention makes it possible to quickly and accurately carry out the bonding process by quickly obtaining the required initial bonding strength in bonding the film-like body and the rib body, and to stably travel even in long-term use. An endless belt for a photographic apparatus and a method for producing the endless belt with high productivity are provided.
[0008]
[Means of order to solve the problems]
The present invention has been made as a result of intensive studies from such a viewpoint,
(1) In an endless belt in which a flexible film-like base material is formed in an annular shape and a guide rib made of a flexible material is joined along the inner peripheral edge, a concave portion is formed on the adhesive surface of the guide rib. An endless belt for an electrophotographic apparatus , wherein the concave portion is filled with a reactive adhesive and bonded thereto; and
(2) In the manufacturing method of an endless belt in which a flexible film-like base material is formed in an annular shape and a guide rib made of a flexible material is joined along a side edge of the inner periphery thereof, the guide rib is bonded. The present invention provides a method for producing an endless belt for an electrophotographic apparatus , wherein a concave portion is formed on the surface, and the concave portion is filled with a reactive adhesive and adhered.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1, the endless belt 1 of the present invention forms a flexible film-like base material 2 in an annular shape. In the present invention, a sheet and a film are used as synonyms and are not distinguished by film thickness. And
An example in which the endless belt 1 is used for an electrophotographic photosensitive member will be described. A photosensitive sheet is used as the flexible film-like substrate 2, and a photosensitive layer is formed on a conductive support in the photosensitive sheet.
The conductive support preferably has a biaxially stretched film laminated with a metal layer. The material of the biaxially stretched film is a linear polyester resin such as polyethylene terephthalate or polybutylene terephthalate, or a polyolefin resin such as polyethylene or polypropylene. Polyvinyl chloride resin and the like can be mentioned. From the viewpoint of mechanical strength, dimensional stability, etc., linear polyester resin, particularly polyethylene terephthalate is preferable.
[0010]
In addition, the thickness of a resin film is about 50-150 micrometers normally.
Moreover, as a metal of the metal vapor deposition layer which comprises an electroconductive support body, although copper, nickel, zinc, aluminum, etc. are mentioned, Among these, aluminum is preferable.
In addition, the thickness of the metal vapor deposition layer is usually about 400 to 1000 mm, and the vapor deposition onto the resin film is performed by a known vapor deposition method such as electrothermal heating melt vapor deposition, in-beam vapor deposition, or ion plating. Made. Moreover, as a metal layer, metal foil, such as aluminum foil and nickel foil, and the laminate film which laminated | stacked these metals can be used. In this case, the metal foil is preferably 5 μm or less.
[0011]
A well-known barrier layer as commonly used can be provided between the conductive support and the photoreceptor layer. As the barrier layer, for example, an organic layer such as polyvinyl alcohol, casein, polyvinyl pyrrolidone, polyacrylic acid, celluloses, gelatin, starch, polyurethane, polyimide, polyamide, etc. is used. Inorganic particles may be added.
The photoreceptor layer may be a single layer type including a charge generation material and a charge transport material, or may be a function separation type in which a charge generation layer and a charge transport layer are laminated. The function separation type photoreceptor is described below as an example.
[0012]
As the charge generation material used in the charge generation layer, any known charge generation material can be used, such as phthalocyanine, azo dye, quinacridone, polycyclic quinone, pyrylium salt, thiapyrylium salt, indigo, dioindigo, anthanthrone, pyranthrone, cyanine. And various organic pigments and dyes. Among these, metal-free phthalocyanine, copper indium chloride, gallium chloride, tin, oxytitanium, zinc, vanadium, and other metals, or oxides and chloride coordinated phthalocyanines are preferable.
[0013]
As the binder for the charge generation layer, a resin such as polyacetal such as polyvinyl butyral, polyvinyl acetate, or phenoxy resin can be used.
The thickness of the charge generation layer is usually 0.1 μm to 1 μm, preferably 0.15 μm to 0.6 μm. The content of the charge generating material used here is 20 to 300 parts by weight, preferably 50 to 200 parts by weight, based on 100 parts by weight of the binder resin.
As the charge transport material in the charge transport layer, low molecular weight compounds such as various pyrazoline derivatives, oxazole derivatives, hydrazone derivatives, stilbene derivatives, and arylamines can be used.
[0014]
A binder resin is blended together with these charge transport materials. Preferred binder resins include, for example, vinyl polymers such as polymethyl methacrylate, polystyrene, polyvinyl chloride, and copolymers thereof, polycarbonate, polyester, polysulfone, polyether, polyketone, phenoxy, epoxy, silicone resin, and the like. These partially crosslinked cured products are also used.
Furthermore, the charge transport layer may contain various additives such as an antioxidant and a sensitizer. The thickness of the charge transport layer is 10 to 40 μm, preferably 10 to 30 μm.
[0015]
The photoreceptor sheet thus obtained is cut to a predetermined size and then joined at both ends. As a bonding method, a heat seal bar or an ultrasonic fusion device can be used even when bonding is performed using an adhesive.
As will be described later, guide ribs may be provided before joining both ends.
When the endless belt of the present invention is used as an intermediate transfer belt, the resin composition of the flexible film-like substrate 2 is not limited to any one of a thermoplastic resin, a thermosetting resin, or rubber. Since a thermoplastic resin or a thermoplastic elastomer can be continuously extruded, it is desirable in terms of production cost.
[0016]
Thermoplastic resins include polyethylene (high density, medium density, low density, linear low density), propylene ethylene block or random copolymer, rubber or latex component such as ethylene / propylene copolymer rubber, styrene / butadiene rubber , Styrene / butadiene / styrene block copolymer or hydrogenated derivatives thereof, polybutadiene, polyisobutylene, polyamide, polyamideimide, polyacetal, polyarylate, polycarbonate, polyphenylene ether, modified polyphenylene ether, polyimide, liquid crystalline polyester, polyethylene terephthalate, Polysulfone, Polyethersulfone, Polyphenylene sulfide, Polybisamide triazole, Polybutylene terephthalate, Polyetherimide, Polyethylene Teretherketone, acrylic, polyvinylidene fluoride, polyvinyl fluoride, ethylene tetrafluoroethylene copolymer, polychlorotrifluoroethylene, tetrafluoroethylene hexafluoropropylene copolymer, tetrafluoroethylene perfluoroalkyl vinyl ether copolymer, poly One of tetrafluoroethylene, fluororubber, alkyl acrylate copolymer, polyester ester copolymer, polyether ester copolymer, polyether amide copolymer, olefin copolymer, polyurethane copolymer, or these Are used.
[0017]
Particularly preferred resins for intermediate transfer belts include polyvinylidene fluoride, polyvinyl fluoride, ethylene tetrafluoroethylene copolymer, polychlorotrifluoroethylene, tetrafluoroethylene hexafluoropropylene copolymer, and tetrafluoroethylene perfluoroalkyl vinyl ether copolymer. Polymers, fluororesins such as polytetrafluoroethylene and fluororubbers are also preferred to prevent contamination from toners, etc. Also, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polyester ester copolymer, polyether ester copolymer An ester-based thermoplastic resin or thermoplastic elastomer such as a coalescence is preferable because the electrical resistance value has little fluctuation in electrical resistance and is stable.
[0018]
Moreover, you may adjust an electrical resistance by adding a conductive filler to these materials. As the conductive filler, at least one selected from carbon black, graphite, carbon fiber, metal powder, conductive metal oxide, organic metal oxide, organic metal compound, organic metal salt, conductive polymer, etc., or the number thereof Those consisting of a mixture of seeds are preferred. Among these, carbon black is particularly preferable. Examples of the carbon black include carbon blacks such as acetylene black, furnace black, and channel black. In order not to impair the appearance of the film, acetylene black having excellent dispersibility is preferred.
[0019]
The blending amount of carbon black varies depending on the type of carbon black, but in the case of acetylene black, 3 to 25 parts by weight is preferable with respect to 100 parts by weight of the thermoplastic resin, and in the case of ketjen black, 1 to 10 parts by weight is preferable. preferable. If it is less than the above range, the conductivity is poor, and if it is above the above range, the appearance of the product is deteriorated and the material strength is lowered, which is not preferable.
The resin composition may contain various additional components that are blended in a normal resin composition as long as the object of the present invention is not impaired. Such components include antioxidants, lubricants, mold release agents and the like.
[0020]
These intermediate transfer belt materials can be obtained by forming a flat sheet using a T die or an annular die, cutting it into a predetermined size, and then joining both ends. For the joining, the means described for the endless belt-like photoreceptor can be used.
Moreover, it is also possible to form a seamless tube by forming into a cylindrical shape by an internal mandrel method using an annular die and cutting it into a predetermined length.
As shown in FIG. 1, along the side edge of the base material 2 having a predetermined width obtained in this way, a preliminarily formed narrow strip-shaped body is joined to form a guide rib 3. Is done.
[0021]
The material of the guide rib 3 is not particularly limited as long as it is flexible and flexible, but an elastomer having a hardness according to JIS K7215 (A type) of 60 degrees or less, preferably 50 degrees or less is preferable. Specifically, neoprene rubber, urethane rubber, butyl rubber, silicone rubber and the like are preferable. Of these, silicone rubber is preferred because of its adhesion to the substrate 2, electrical insulation, environmental properties such as moisture resistance, solvent resistance, ozone resistance, and heat resistance. Silicone rubber is preferably a one-component room-temperature curing type due to workability, formability, damage to the base material, etc., and further deformed by gravity in the shaped state before curing due to the dimensional accuracy of the obtained guide It is preferable to have semi-fluidity that does not occur. As a solvent capable of dissolving the silicone rubber before curing, an alcohol-based solvent is desirable because it does not damage the belt base material in terms of safety. Specifically, ethyl alcohol and isopropanol are used.
[0022]
The cross-sectional shape of the guide rib 3 is not particularly limited, but generally the cross-sectional shape is rectangular, rectangular, triangular, or trapezoidal as shown in FIG.
Therefore, in the present invention, the convex portion 3a and the concave portion 3b are formed on the bonding surface of the guide rib 3, and the bonding surface has a concavo-convex structure.
The cross-sectional structure of the recess 3b is not particularly limited and can be an arbitrary cross-sectional shape, and can be a recess that is enlarged inside as shown in FIG.
The depth of the recess 3b is generally 0.1 mm or more, preferably about 0.2 to 3 mm.
The recess 3b is generally formed in a groove shape that is continuous in the length direction, but may be formed intermittently according to the purpose. Further, two or more can be provided in parallel as shown in FIG.
[0023]
In addition, as shown in FIG. 3, it is also preferable to attach a double-sided pressure-sensitive adhesive tape 4 to the adhesive surface of the convex portion 3a because the adhesive strength can be increased. The double-sided pressure-sensitive adhesive tape 4 may be affixed to the entire convex portions 3a, 3a of the guide rib 3 as shown in FIG. 3 (A), or may be attached to a part thereof as shown in FIG. 3 (B). It may be affixed.
When joining the guide rib 3 to the film-like substrate 2, as shown in FIG. 4, a reactive adhesive 5 is applied to the adhesive surface of the guide rib 3, and the concave portion 3b is filled with the adhesive 5. And applied to the adhesive surface of the convex portion 3a.
[0024]
A reactive adhesive is used as the adhesive, and a urethane adhesive, an acrylic adhesive, a silicon adhesive, an epoxy adhesive, or the like can be used.
The guide ribs 3 filled with the adhesive 5 are attached along both side edges of the back surface of the film-like substrate 2, and the guide ribs 3 are formed by curing the adhesive.
The guide rib 3 may be joined to the base material 2 after joining both end portions of the base material 2 to form an annular shape. Also, the guide ribs 3 are guided to the flat base material 2 before joining the both end portions. After joining the rib 3, both ends of the base material 2 may be joined to form an annular shape.
[0025]
According to the present invention, since the adhesive is attached to the concave portion 3b of the guide rib 3 while being filled with the adhesive, the adhesion becomes strong, and the adhesive on the surface of the convex portion 3a has a small film thickness, so that the predetermined thickness is obtained. The initial adhesive strength can be obtained quickly.
Further, when the double-sided pressure-sensitive adhesive tape 4 is applied as shown in FIGS. 3A and 3B, the base material 2 and the guide ribs are provided by the double-sided pressure-sensitive adhesive tape 4 even before the adhesive is cured. In order to fix 3, the guide rib 3 is not displaced and can be joined to an accurate position.
The endless belt 1 of the present invention can be used as the endless belt-like photosensitive member 20 shown in FIG. 5 or as the intermediate transfer belt 30 shown in FIG. 6, and as shown in FIG. It can be driven using a roll 35 having tapered rings 34, 34.
[0026]
【Example】
The present invention will be described more specifically with reference to the following examples and comparative examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In the following examples, “part” means “part by weight”.
Example 1
Add 30 parts of n-propanol to 1.6 parts of oxytitanium phthalocyanine showing a strongest peak at a flag angle (2θ ± 0.2 °) of 27.3 ° in a powder X-ray diffraction spectrum by Cu-Kα ray, The mixture was pulverized with a sand grind mill for 6 hours and finely dispersed. The dispersion obtained here was composed of 8 parts of a 5% methanol solution of polyvinyl butyral (manufactured by Denka Co., Ltd., trade name # 6000-C) and the exemplified polyester resin (2) (weight average molecular weight 7.8 × 10 ³ ). In addition to 8 parts of a 5% methanol solution, the mixture was further diluted with methanol to finally produce a dispersion having a solid content concentration of 3.0%.
[0027]
Next, this dispersion was applied onto an aluminum deposition surface deposited on a biaxially stretched polyester film having a thickness of 75 μm by a bar coater so that the thickness after drying was 0.4 μm to provide a charge generation layer. . Next, on the charge generation layer, 60 parts by weight of the following hydrazone compound [A] as a charge transport material:
[Chemical 1]

[0029]
0.5 part by weight of the following cyano compound,
[0030]
[Chemical formula 2]

[0031]
2,6-ditertiarybutylhydroxytoluene (BHT) 8 parts by weight and, as a binder, 100 parts by weight of a polycarbonate resin (manufactured by Mitsubishi Chemical Corporation, “Novalex” (trademark) 7030A), 1000 parts by weight of 1,4-dioxane The solution dissolved in the part was applied with a film applicator, and a charge transport layer was provided so that the film thickness after drying was 17 μm.
On the other hand, a silicone rubber (Toray Dow Corning Silicone) is formed on a mold plate having a shape of a rectangular parallelepiped having a cross section of 3 mm × 1 mm as shown in FIG. 2B and having two recesses of 1 mm × 0.2 mm in parallel. SE9155 manufactured by Co., Ltd.) was filled and cured to form a strip-shaped guide rib.
The same silicon rubber as described above was applied to the adhesive surface to fill the recesses and applied to the adhesive surface.
[0032]
This was affixed along both side edges of the photoreceptor sheet. When it was allowed to stand as it was, curing of the adhesive progressed after 10 minutes, and it did not deviate with a little force.
The photoreceptor sheet with the guide ribs bonded thereto was fused at both ends by an ultrasonic sealer to obtain an endless belt-like photoreceptor.
This was filled in a commercially available color electronic copying machine and a 60,000 copy test was conducted, but no color shift occurred.
[0033]
Comparative Example 1
Exactly the same operation as in Example 1 was performed except that the concave surface was not formed on the joint surface of the guide rib and the surface was flat.
As a result, 20 minutes after attaching the guide ribs to the base material, the adhesive was still insufficiently cured, and peeling and displacement occurred with a slight force. It took 35 minutes to cure to such an extent that no deviation occurred.
[Brief description of the drawings]
FIG. 1 is a partially cutaway perspective view showing an embodiment of an endless belt of the present invention.
FIG. 2 is a longitudinal sectional view showing various examples of guide ribs used in the present invention.
FIG. 3 is a longitudinal sectional view showing another example of the guide rib used in the present invention.
FIG. 4 is a longitudinal sectional view of a guide rib when an adhesive is applied.
FIG. 5 is a side view showing an endless belt-like photoconductor.
FIG. 6 is a side view showing an intermediate transfer belt.
FIG. 7 is a partially cutaway perspective view showing a roll for driving an endless belt.
FIG. 8 is a partial cutaway side view showing another example of a roll for driving an endless belt.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Endless belt 2 Base material 3 Guide rib 3a Convex part 3b Concave part 4 Double-sided pressure sensitive adhesive tape 5 Adhesive 20 Endless belt-shaped electrophotographic photoreceptor 30 Intermediate transfer belts 32, 35 Roll

Claims (6)

In an endless belt in which a flexible film-like base material is formed in an annular shape and a guide rib made of a flexible material is joined along the inner peripheral edge, a concave portion is formed on the adhesive surface of the guide rib. An endless belt for an electrophotographic apparatus , wherein the recess is filled with a reactive adhesive and adhered thereto .   The endless belt for an electrophotographic apparatus according to claim 1, wherein the endless belt is an endless belt-shaped electrophotographic photosensitive member.   The endless belt for an electrophotographic apparatus according to claim 1, wherein the endless belt is an intermediate transfer belt of an electrophotographic apparatus. In a manufacturing method of an endless belt in which a flexible film-like base material is formed in an annular shape and a guide rib made of a flexible material is joined along an inner peripheral side edge thereof, a concave portion is formed on an adhesive surface of the guide rib. A process for producing an endless belt for an electrophotographic apparatus , wherein the concave portion is filled with a reactive adhesive and adhered.   The method for producing an endless belt for an electrophotographic apparatus according to claim 4, wherein the reactive adhesive is a silicon-based adhesive. Claim 4 or 5 method of manufacturing an endless belt for an electrophotographic apparatus according performed impregnated with two-sided pressure sensitive adhesive tape to a part even without least guide ribs adhesive surface.

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