JP2005182003A - Electrophotographic endless belt, method for manufacturing electrophotographic endless belt, and electrophotographic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic endless belt excellent in uniformity of thickness and transfer performance and excellent also in durability, a method for manufacturing the electrophotographic endless belt, and an electrophotographic apparatus provided with the electrophotographic endless belt. <P>SOLUTION: In the electrophotographic endless belt having a resin layer composed of a polyamide-containing resin composition, the resin composition further contains a copolymer obtained by copolymerizing an olefin and an oxygen-containing heterocyclic compound, a curve (T-log<SB>10</SB>η curve) showing relationships between temperature of the resin composition and common logarithm of melt viscosity of the resin composition has a slow inclining region whose gradient (Δlog<SB>10</SB>η/ΔT) is -0.02 to 0 in the log<SB>10</SB>η range of log<SB>10</SB>1,000-log<SB>10</SB>8,000, a temperature range of the slow inclining region is ≥10°C, a maximum thickness of the resin layer is ≤115% of an average thickness of the resin layer, and a minimum thickness of the resin layer is ≥85% of the average thickness of the resin layer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electrophotographic endless belt such as an intermediate transfer belt or a transfer material conveying belt, a method for manufacturing an electrophotographic endless belt, and an electrophotographic apparatus having the electrophotographic endless belt.

  In addition to rigid drums, transfer material transport members and intermediate transfer members used in electrophotographic devices such as copiers and laser beam printers have flexible endless belts (seamless belts) (electrophotography) Endless belts (electrophotographic seamless belts) are used.

In recent years, color (full color, etc.) electrophotographic apparatuses have been put into practical use, and the demand for electrophotographic endless belts such as a transfer material conveying belt and an intermediate transfer belt is increasing.
In recent years, an endless belt having a layer (resin layer) made of a resin composition containing a resin has been widely used as an electrophotographic endless belt.

  As a resin used in this resin composition, for example, Japanese Patent Application Laid-Open No. 03-089357 (Patent Document 1) and Japanese Patent Application Laid-Open No. 05-345368 (Patent Document 2) disclose polycarbonate. No. 0-25232 (Patent Document 3) discloses an ethylene-tetrafluoroethylene copolymer (ETFE), and Japanese Patent No. 028445059 (Patent Document 4) discloses a polymer blend of polyalkylene terephthalate and polycarbonate. It is disclosed.

However, when these resins are used in an electrophotographic endless belt, there are the following problems.
For example, polycarbonate is not very high in crack resistance, and therefore, when an endless belt using the polycarbonate is repeatedly used, cracks are likely to occur and the life is short.
In addition, since the ethylene-tetrafluoroethylene copolymer is easy to be creeped, the endless belt using this is repeatedly used, so that the endless belt is extended and has a short life. As a method of reducing the amount of creep, there is a method of increasing the thickness of the endless belt. However, if the thickness of the endless belt is increased, the crack resistance is lowered. Also, there is a method to add a mechanism to change the tension applied to the endless belt according to the length of the endless belt to the mechanism that stretches the endless belt installed in the main body of the electrophotographic apparatus, thereby suppressing the harmful effects caused by the creep of the endless belt. In this case, however, the number of parts increases, leading to an increase in size and cost of the electrophotographic apparatus main body.
In addition, although polymer blends of polyalkylene terephthalate and polycarbonate are somewhat more resistant to cracking than polycarbonate, the actual situation is that they cannot fully meet the recent demands for higher image quality and higher durability. is there.

  As a method for solving these problems, there is a method in which polyamide having high toughness among engine plastics is used for an electrophotographic endless belt (for example, JP-A-11-352796 (Patent Document 5) and JP-A-2001-350347 (Patent Document)). Reference 6)).

Japanese Patent Laid-Open No. 03-089357 JP 05-345368 A Japanese Patent Publication No. 08-025232 Japanese Patent No. 02845059 Japanese Patent Application Laid-Open No. 11-352796 JP 2001-350347 A

However, since the change rate of the melt viscosity with respect to temperature is large in polyamide, the molding stability is lowered and the thickness unevenness is increased even if the molding conditions fluctuate. When an electrophotographic endless belt having a large thickness unevenness is used as an endless belt-shaped transfer member such as a transfer material conveying belt or an intermediate transfer belt, transferability is deteriorated. Specifically, transfer unevenness or transfer loss occurs in the output image.
An object of the present invention is to provide an electrophotographic endless belt having excellent thickness uniformity and transferability and excellent durability, a method for producing the electrophotographic endless belt, and an electrophotographic apparatus having the electrophotographic endless belt. It is to be.

The present invention relates to an electrophotographic endless belt having a resin layer made of a resin composition containing polyamide.
The resin composition further contains a copolymer obtained by copolymerization of a heterocyclic compound containing olefin and oxygen,
The curve (T-log ₁₀ η curve) showing the relationship between the temperature (T [° C.]) of the resin composition and the common logarithm (log ₁₀ η) of melt viscosity (η [Pa · s]) is log ₁₀ 1000. A log ₁₀ η range of ˜log ₁₀ 8000 has a slow slope region with a slope (Δlog ₁₀ η / ΔT) of −0.02 to 0, and the temperature range of the slow slope region is 10 ° C. or more,
The maximum value of the thickness of the resin layer is 115% or less of the average value of the thickness of the resin layer, and the minimum value of the thickness of the resin layer is 85% of the average value of the thickness of the resin layer The electrophotographic endless belt is characterized by the above.

The present invention also provides a method for producing an electrophotographic endless belt having a resin layer made of a resin composition containing polyamide, wherein the annular die is removed from the inside of an extruder connected to the annular die. A step of obtaining a cylindrical body of the resin composition by extruding to the outside of the extruder via, and a step of molding the resin layer of the electrophotographic endless belt using the cylindrical body of the resin composition In the method for producing an electrophotographic endless belt,
The resin composition further contains a copolymer obtained by copolymerization of a heterocyclic compound containing olefin and oxygen,
The curve (T-log ₁₀ η curve) showing the relationship between the temperature (T [° C.]) of the resin composition and the common logarithm (log ₁₀ η) of melt viscosity (η [Pa · s]) is log ₁₀ 1000. A log ₁₀ η range of ˜log ₁₀ 8000 has a slow slope region with a slope (Δlog ₁₀ η / ΔT) of −0.02 to 0, and the temperature range of the slow slope region is 10 ° C. or more,
The temperature of the resin composition when extruding the resin composition is within the temperature range of the gently inclined region. Further, the present invention is an electrophotographic apparatus having the electrophotographic endless belt or the electrophotographic endless belt manufactured by the manufacturing method.

  According to the present invention, an electrophotographic endless belt excellent in thickness uniformity and transferability and excellent in durability, a method for producing the electrophotographic endless belt, and an electrophotographic apparatus having the electrophotographic endless belt are provided. can do.

  In the present invention, the “resin layer” is a layer made of a resin composition containing a resin (and containing various additives as necessary). An endless belt having a resin layer is composed of a single resin layer (single-layer endless belt), a laminate of a plurality of resin layers, or a laminate of a resin layer and a layer other than the resin layer. However, the present invention is applicable to any endless belt having a resin layer regardless of the layer configuration. When the electrophotographic endless belt is a laminated type, the resin layer to which the present invention is applied may be any of a surface layer, an intermediate layer, and a base layer.

The present invention is described in detail below.
The polyamide is contained by adding a copolymer obtained by copolymerization of a heterocyclic compound containing olefin and oxygen (hereinafter also referred to as “specific modified olefin”) to the resin composition containing polyamide. The rate of change of the melt viscosity with respect to the temperature of the resin composition can be reduced, thereby improving molding stability and suppressing variation in extrusion when molding using an extruder, resulting in uneven thickness. A small resin layer can be obtained.
The specific modified olefin is not limited to that of a binary copolymer, and may be a ternary or higher copolymer further using an olefin or a compound other than a heterocyclic compound containing oxygen. Examples of the compound other than the heterocyclic compound containing olefin and oxygen include vinyl acetate and methyl acrylate.

The T-log ₁₀ η curve (T: temperature [° C.], η: melt viscosity [Pa · s]) of the resin composition containing the polyamide and the specific modified olefin used in the present invention is as described above.
Log ₁₀ 1000 to log ₁₀ 8000 has a gentle slope region with a slope (Δlog ₁₀ η / ΔT) of −0.02 to 0 in a log ₁₀ η range of log ₁₀ 8000, and
The temperature range of the gentle slope region is 10 ° C. or higher,
The condition that the rate of change in the melt viscosity with respect to the temperature of the resin composition is sufficiently small is within a range that can sufficiently cope with fluctuations in the molding conditions (extrusion conditions). Means that. By extruding the resin composition so that the temperature of the resin composition falls within the temperature range of the gently inclined region, a resin layer with small thickness unevenness can be obtained even if the extrusion conditions fluctuate. It can be done.
In addition, when the above-mentioned gentle slope region is in a region exceeding log ₁₀ 8000, and extrusion is performed with the temperature of the resin composition being the temperature of the gentle slope region, a high pressure is required for extrusion, Molding is not stable and thickness unevenness is likely to occur. On the other hand, when the above-mentioned gentle slope region is in a region of less than log ₁₀ 1000, and the extrusion is performed with the temperature of the resin composition being the temperature of the slow slope region, the melt viscosity of the resin composition is too low. As a result, undulation occurs during molding, and thickness unevenness is likely to occur.

FIG. 5 shows an example of the T-log ₁₀ η curve.
Like curve (1) in FIG. 5, the slope of the T-log ₁₀ η curve (Δlog ₁₀ η / ΔT) is outside the range of −0.02 to 0, that is, the melt viscosity with respect to the temperature of the resin composition. When the rate of change is large, it becomes impossible to sufficiently cope with fluctuations in the molding conditions (extrusion conditions). Curves (2) and (3) are curves having a gentle slope region in which the slope (Δlog ₁₀ η / ΔT) of the T-log ₁₀ η curve is −0.02 to 0.

  In the present invention, the melt viscosity of the resin composition is measured as follows using a flow tester CFT-500D manufactured by Shimadzu Corporation.

<Sample preparation>
The resin composition is powdered so that the cylinder can be filled through the cylinder hole of the flow tester, and this is dried in an environment of a temperature of 75 to 85 ° C. and a humidity of 0 to 50% RH for 4 hours.

なお、上記式（１）中のγは剪断速度［ｓ^−１］であって、流出速度Ｑ［ｃｍ^３／ｓ］およびダイの穴の直径Ｄ［ｍｍ］と
γ＝（３２Ｑ／πＤ^３）×１０^３
の関係にあり、また、τは剪断応力［Ｐａ］であって、試験圧力Ｐ［ＭＰａ］、ダイの穴の直径Ｄ［ｍｍ］およびダイの長さＬ［ｍｍ］と
τ＝ＰＤ／４Ｌ
の関係にある。また、流出速度Ｑ［ｃｍ^３／ｓ］は、計測時間ｔ［ｓ］、計測時間ｔ［ｓ］に対するピストンの移動量Ｘ［ｍｍ］およびピストンの断面積Ａ［ｃｍ^２］と
Ｑ＝（Ｘ／１０）×（Ａ／ｔ）
の関係にある。 <Measurement method>
Under a constant temperature, a 5 kg load (test pressure P = 0.49 MPa) is applied to the sample from the plunger through the piston, and the hole is extruded from a die having a diameter D = 1 mm and a length L = 1 mm. Measure the movement of the piston of the flow tester. The amount of movement, that is, the outflow rate is measured at each temperature, and the melt viscosity η [Pa · s] is obtained from the value by the following equation (1).

In the above formula (1), γ is the shear rate [s ⁻¹ ], and the outflow rate Q [cm ³ / s] and the die hole diameter D [mm] and γ = (32Q / πD ³ ) × 10 ³
Τ is the shear stress [Pa], and the test pressure P [MPa], the die hole diameter D [mm], and the die length L [mm] and τ = PD / 4L
Are in a relationship. In addition, the outflow velocity Q [cm ³ / s] is determined by measuring time t [s], moving amount X [mm] of the piston with respect to the measuring time t [s], and cross-sectional area A [cm ² ] of the piston Q = (X / 10) × (A / t)
Are in a relationship.

なお、上記式（２）中、
η_Ｔｏ＋５：Ｔｏ＋５［℃］における溶融粘度［Ｐａ・ｓ］
η_Ｔｏ−５：Ｔｏ−５［℃］における溶融粘度［Ｐａ・ｓ］
である。 <Measurement conditions>
Temperature increase rate: 5 ° C / min
Measurement interval: 2 ° C ^-1
Preheating time: 120s
Plunger area: 1 cm ²
Measurement using the above flow tester is performed in the temperature range of 20 to 30 ° C. and humidity of 30 to 70% RH, and the common logarithm of melt viscosity is plotted at each temperature of 1 ° C. to obtain a T-log ₁₀ η curve.
In the present invention, the slope Δlog ₁₀ η / ΔT at an arbitrary temperature (To [° C.) of the T-log ₁₀ η curve is defined by the following equation (2).

In the above formula (2),
η _{To + 5} : Melt viscosity [Pa · s] at To + 5 [° C.]
η _To-5 : Melt viscosity [Pa · s] at To-5 [° C.]
It is.

The slope of the T-log ₁₀ η curve (Δlog ₁₀ η / ΔT) of the resin composition containing polyamide and the above-mentioned specific modified olefin and the temperature range of the gentle slope region are the type of polyamide, the polyamide and the specific modified olefin Varies depending on the mixing ratio. In addition, the type of the specific modified olefin, specifically, the type of the olefin that is the raw material of the specific modified olefin, the type of the heterocyclic compound containing oxygen, or the heterocyclic containing the olefin and the oxygen It also varies depending on the copolymerization ratio with the compound. Furthermore, it changes also with the kind of components other than the polyamide contained in a resin composition and the said specific modified olefin, those compounding ratios, and those coupling | bonding states.
Therefore, the resin composition containing polyamide and the specific modified olefin is
· _{T-log 10 η curve,} the slope in _{log 10} eta range of _{log 10 1000~log 10 8000 (Δlog 10} η / ΔT) has a gentle slope region is -0.02～0 and
The temperature range of the gentle slope region is 10 ° C. or higher,
In order to satisfy the above condition, it is necessary to appropriately adjust the above-mentioned types and ratios.
For example, as the amount of the specific modified olefin is increased with respect to the amount of polyamide, the amount of the unit derived from the heterocyclic compound containing oxygen is increased with respect to the amount of the unit derived from olefin in the specific modified olefin. The absolute value of the slope (Δlog ₁₀ η / ΔT) of the T-log ₁₀ η curve of the resin composition tends to decrease as the value increases. However, if the amount of polyamide in the resin composition is too small, the effect of using the above-mentioned polyamide becomes poor.

From the above viewpoint, the ratio of the polyamide in the resin composition is preferably 40 to 74% by mass with respect to the total mass of the resin composition, and the ratio of the specific modified olefin in the resin composition is the resin composition. It is preferable that it is 1-40 mass% with respect to the total mass of the polyamide in a thing and the said specific modified olefin.
The polyamide is at least one selected from the group consisting of polyamide 6 · 10 (nylon 6 · 10), polyamide 6 · 12 (nylon 6 · 12), polyamide 11 (nylon 11) and polyamide 12 (nylon 12). It is preferable that the resin is.
Moreover, ethylene is preferable as the olefin that is a raw material of the specific modified olefin, and glycidyl methacrylate and maleic anhydride are preferable as the heterocyclic compound containing oxygen.
In addition, the ratio of the olefin-derived unit to the oxygen-containing heterocyclic compound-containing unit in the specific modified olefin is preferably in the range of 99: 1 to 83:12. The olefin molecule is preferably a molecule in which a unit derived from an olefin and a unit derived from a heterocyclic compound containing oxygen are linearly bonded.

A copolymer obtained by copolymerization of the above-mentioned specific modified olefin, that is, a heterocyclic compound containing olefin and oxygen is available as a product.
For example, as a copolymer product (ethylene-glycidyl methacrylate copolymer) obtained by copolymerization of ethylene and glycidyl methacrylate, “Bond First E” (unit derived from ethylene / derived from glycidyl methacrylate) manufactured by Sumitomo Chemical Co., Ltd. Unit = 88/12), “bond first 2C” manufactured by Sumitomo Chemical Co., Ltd. (unit derived from ethylene / unit derived from glycidyl methacrylate = 94/6), and “bond first 2B manufactured by Sumitomo Chemical Co., Ltd.” "(Unit derived from ethylene / Unit derived from glycidyl methacrylate / Unit derived from vinyl acetate = 83/12/5)" or "Bond First 7B" manufactured by Sumitomo Chemical Co., Ltd. (Unit derived from ethylene / Unit derived from glycidyl methacrylate) / Uni from vinyl acetate G = 83/12/5), “Bond First 7L” manufactured by Sumitomo Chemical Co., Ltd. (units derived from ethylene / units derived from glycidyl methacrylate / units derived from methyl acrylate = 67/3/30), Sumitomo “Bond First 7M” manufactured by Kagaku Co., Ltd. (units derived from ethylene / units derived from glycidyl methacrylate / units derived from methyl acrylate = 64/6/30) and the like. Each of these products is a molecule in which an olefin (ethylene) -derived unit and an oxygen-containing heterocyclic compound (glycidyl methacrylate) -derived unit are linearly bonded.
In addition, as a product of a copolymer (ethylene-maleic anhydride copolymer) obtained by copolymerization of ethylene and maleic anhydride, for example, “F3000” (unit derived from ethylene / anhydrous made by Ube Industries) And maleic acid-derived unit = 99/1). Other examples include “Nack Ace GA-002” and “Nack Ace GA-004” manufactured by Nippon Unicar Co., Ltd.

  As a method of mixing the polyamide and the specific modified olefin, a method of kneading these with a kneader (such as a single-screw kneader or a twin-screw kneader) is preferable.

Next, the method for producing the electrophotographic endless belt of the present invention will be described more specifically.
As described above, the method for producing an electrophotographic endless belt of the present invention is a cylinder of a resin composition by extruding a resin composition from the inside of an extruder connected to an annular die to the outside of the extruder via the annular die. And a step of forming a resin layer of an electrophotographic endless belt using a cylindrical body of a resin composition.
In the step of forming the resin layer of the electrophotographic endless belt using the cylindrical body of the resin composition, the molding is performed under the condition that the thickness of the resin layer of the electrophotographic endless belt is thinner than the die gap of the annular die. It is preferable.
For example, when a resin layer having a thickness of 150 μm is formed with an annular die having a die gap of 150 μm, the thickness of the resin layer changes by 10 μm as it is when the die gap is shifted by 10 μm. In order to reduce the thickness of the resin layer to 1 μm or less, the die gap must be controlled to be 1 μm or less. However, it is difficult to adjust the die gap in units of 1 μm. Will be difficult.
However, if a resin layer having a thickness of 150 μm is molded with an annular die having a die gap of 1500 μm, the change in thickness of the resin layer is 1/10 of that even if the die gap is shifted by 10 μm, that is, 1 μm. Thus, the unevenness of the thickness of the resin layer can be reduced.

Examples of the method of reducing the thickness of the resin layer from the die gap of the annular die include, for example, a method of expanding and expanding the cylindrical body of the resin composition so that the diameter of the resin layer is larger than the diameter of the annular die, The method of making this take-up speed faster than the extrusion speed of the cylindrical body of the resin composition extruded from is mentioned.
When the former method is adopted, the enlargement ratio (resin layer diameter / annular die diameter) is preferably 4.0 or less. If the enlargement ratio is too large, unevenness in the thickness of the resin layer may increase.
The latter method is useful when the melt viscosity of the resin composition is relatively low. This is because when the melt viscosity of the resin composition is low, a hole may be formed when the resin composition is expanded. When the latter method is adopted, the enlargement ratio can be 1 or less, but is preferably 0.5 or more. If the enlargement ratio is too small, it is necessary to greatly increase the take-up speed, which may increase the thickness unevenness of the resin layer.
As an example of the former method, that is, a method of expanding and expanding the cylindrical body of the resin composition so that the diameter of the resin layer is larger than the diameter of the annular die, an inflation molding method may be mentioned.

FIG. 1 is a diagram showing an example of a schematic configuration of an apparatus for molding a resin layer of an electrophotographic endless belt by an inflation molding method.
First, a resin composition obtained by premixing polyamide and the above-mentioned specific modified olefin based on a predetermined formulation is charged into the extruder 101 from the hopper 102. The temperature and screw configuration in the extruder 101 are selected so that the resin composition has a meltable melt viscosity and the polyamide and the specific modified olefin are uniformly dispersed.
The resin composition is melted and kneaded in the extruder 101 to become a melt, and is discharged out of the extruder 101 via the annular die 103 to become a cylindrical body of the resin composition.

In the case of the inflation molding method, for example, a gas introduction path 104 is provided in the annular die 103, and a gas 105 (air, nitrogen, carbon dioxide, argon, etc.) having a pressure equal to or higher than atmospheric pressure is passed from the gas introduction path 104 to the annular die 103. As a result, the cylindrical body of the resin composition expands and expands in the radial direction to form a resin composition film 106. The molding may be performed without blowing the gas 105 into the gas introduction path 104.
The temperature of the resin composition at the time of extruding the resin composition can be measured by the thermometer 120 or by a thermometer (not shown) disposed in the vicinity of the outlet of the annular die 103.

The resin composition film 106 is pulled upward by a pinch roller 108 while being cooled by a cooling ring (not shown). By passing between the dimension stabilizing guides 107 of a predetermined dimension when pulled up, the circumferential length (circumferential length) of the resin layer of the electrophotographic endless belt is determined, and the cutter 109 has a desired length. The length (width) of the resin layer of the electrophotographic endless belt in the bus line direction is determined.
In this way, the resin layer of the electrophotographic endless belt can be formed. In the case of a single layer type electrophotographic endless belt, this resin layer is an electrophotographic endless belt.

In the case of an electrophotographic endless belt having two resin layers, when both resin layers are formed by an inflation molding method, as shown in FIG. 2, the second extruder 201 (202 is a second extruder). The hopper is installed, and the cylindrical body of the resin composition from the extruder 101 and the cylindrical body of the resin composition from the extruder 201 are simultaneously fed into the annular die 103, and two layers are expanded and expanded simultaneously. An electrophotographic endless belt having the configuration can be obtained. When there are three or more layers, an extruder may be prepared according to the number of layers. 210 is a thermometer for measuring the temperature of the resin composition.
In addition, when the resin composition film is cut into a predetermined length by a cutter, it is preferable to continuously cut the resin composition film in a direction perpendicular to the generatrix direction. In the case of continuous cutting, it is preferable to use a cutter that moves at the same speed as the take-off speed because if the cutter is cut in a stopped state, there is a time difference between the start and end of cutting and the cut is performed obliquely.

As a method for removing the crease of the endless belt or smoothing the endless belt surface, for example, there is a method of using a set of cylindrical molds made of materials having different coefficients of thermal expansion and having different diameters.
Specifically, after the thermal expansion coefficient of the small-diameter cylindrical mold (inner mold) is larger than the thermal expansion coefficient of the large-diameter cylindrical mold (outer mold), the endless belt molded on this inner mold is covered. The inner mold is inserted into the outer mold so that the cylindrical film is sandwiched between the inner mold and the outer mold. The gap between the inner mold and the outer mold is obtained by calculating the difference between the heating temperature and the coefficient of thermal expansion between the inner mold and the outer mold and the required pressure.

  From the inside, the mold set in the order of the inner mold, endless belt, and outer mold is heated to near the softening point temperature of the polyamide resin used for the endless belt. Since the inner mold having a large coefficient of thermal expansion tends to expand beyond the inner diameter of the outer mold by heating, a uniform pressure is applied to the entire endless belt. At this time, the surface of the endless belt that has reached the vicinity of the softening point is pressed against the inner surface of the outer mold, and the crease can be removed. Then, the endless belt from which the crease has been removed can be obtained by cooling and removing the endless belt from the mold. According to this method, it is possible to adjust the dimensions and improve the surface properties at the same time. Moreover, if the endless belt which covers the inner mold is stacked, a multi-layered endless belt can be obtained.

The electrophotographic endless belt of the present invention can be manufactured by the manufacturing method described above.
The volume resistivity of the electrophotographic endless belt is preferably 10 ⁰ to 10 ¹³ Ω · cm, and more preferably 10 ⁸ to 10 ¹³ Ω · cm.
Further, the surface resistance value of the electrophotographic endless belt is preferably 10 ⁰ to 10 ¹⁷ Ω / □, and more preferably 10 ⁶ to 10 ¹⁴ Ω / □.
In order to adjust the volume resistivity and surface resistance value of the electrophotographic endless belt as described above, for example, a conductive agent may be added. As the conductive agent, either an electroconductive conductive agent or an ionic conductive conductive agent is used. May be used.

Examples of the electronic conductive agent include conductive carbon such as ketjen black and acetylene black, carbon for rubber such as SAF, ISAF, HAF, FEF, GPF, SRF, FT, and MT, and color ink subjected to oxidation treatment. Carbon, pyrolytic carbon, graphite such as natural graphite and artificial graphite, metal powder such as copper, nickel, iron and aluminum, metal oxide powder such as titanium oxide, zinc oxide and tin oxide, polyaniline, polypyrrole and polyacetylene Examples thereof include conductive polymers.
Examples of the ion conductive conductive agent include lauryltrimethylammonium, stearyltrimethylammonium, octadodecyltrimethylammonium, dodecyltrimethylammonium, hexadecyltrimethylammonium, perchlorate, chlorate, borofluoride of modified fatty acid dimethylethylammonium. Cationic surfactants, such as quaternary ammonium salts such as hydrates, sulfates, etosulphate salts, benzyl bromides, benzyl chlorides such as benzyl chlorides, aliphatic sulfonates, higher alcohol sulfates Anionic surfactants such as ester salts, higher alcohol ethylene oxide addition sulfate ester salts, higher alcohol phosphate ester salts, higher alcohol ethylene oxide addition phosphate ester salts, amphoteric ions such as various betaines Emissions surfactants, higher alcohol ethylene oxide, polyethylene glycol fatty acid esters, polyhydric antistatic agent such as a non-ionic surfactant such as alcohol fatty acid _{esters, LiCF 3 SO 3, NaClO 4} , LiClO 4, LiAsF 6, LiBF 4 , Na SCN, KSCN, NaCl ⁺ Li ⁺ , Na ⁺ , K ⁺ group 1 metal salts such as NH ^{+ +} , electrolytes such as NH ^{4 +} salts, and Ca ²⁺ such as Ca (ClO ₄ ) ₂ Metal salts belonging to Group 2 of the periodic table such as Ba ^{2+ and the} like, and those having groups having active hydrogen which react with isocyanate such as at least one hydroxyl group, carboxyl group, primary or secondary amine group Is mentioned. In addition, with such compounds, complexes of polyhydric alcohols such as 1,4-butanediol, ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol and their derivatives, and monools such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether Of the complex.
One type or two or more types of conductive agents can be used.

  Moreover, arbitrary additives can also be added in the range which does not impair the effect of this invention. For example, hydrolysis inhibitors (carbodiimide, etc.), antioxidants (phenol, phosphorus, sulfur, amine, etc.), light stabilizers (HALS), flame retardants (halogen, phosphorus, antimony, hydroxylation) Magnesium and silicone resins), lubricants (such as fluororesins and silicone oils), and reinforcing agents (such as glass fibers, carbon fibers and aramid fibers). One kind or two or more kinds of additives can be used.

The volume resistivity and surface resistance value of the electrophotographic endless belt are preferably set so that the maximum values are within 20 times the minimum values.
In particular, the maximum value of the volume resistivity in the circumferential direction of the electrophotographic endless belt is preferably within 20 times the minimum value. This is because, when the maximum volume resistivity in the circumferential direction is larger than 20 times the minimum value, uneven transfer occurs in the circumferential direction, or when a voltage is applied at a plurality of locations, some locations where the voltage is applied This is because a current may flow from a portion where the resistance in the circumferential direction is low to a portion to which it is applied, and normal operation may not be performed by disturbing voltage control at the other portion.
Moreover, it is preferable that the maximum value of the surface resistance value in the circumferential direction is within 20 times the minimum value. This is because if the maximum surface resistance value in the circumferential direction of the belt is larger than 20 times the minimum value, uneven transfer occurs in the circumferential direction, or when a voltage is applied at a plurality of locations, a part of the voltage is applied. This is because the current flows from the part to another applied part through a part having a low resistance in the circumferential direction, and the voltage control at the other part is disturbed, so that a normal operation may not be performed.

Moreover, it is preferable that the maximum value of the volume resistivity in the bus direction is within 20 times the minimum value. This is because if the maximum value of volume resistivity in the busbar direction is larger than 20 times the minimum value, transfer unevenness may occur in the busbar direction, or excessive current may flow into the minimum resistance region, causing the device to malfunction. Because.
Moreover, it is preferable that the maximum value of the surface resistance value in the busbar direction is within 20 times the minimum value. This is a cleaning method in which if the maximum surface resistance value in the bus bar direction is larger than 20 times the minimum value, transfer unevenness occurs in the bus bar direction or a predetermined charge is given to the transfer residual toner to return it to the electrophotographic photosensitive member. This is because an excessive current flows from the charging member that gives electric charge to the portion having the minimum surface resistance value of the belt, and a sufficient electric field is not applied in the direction of the bus at that portion, so cleaning unevenness may occur in the direction of the bus. .

It should be noted that the volume resistivity and the surface resistance value are not merely differences in measurement conditions, but show completely different electrical characteristics. That is, when the voltage / current applied to the electrophotographic endless belt is applied in the thickness direction, the movement of the electric charge of the electrophotographic endless belt is mainly determined by the structure and physical properties inside the electrophotographic endless belt. As such, the surface potential of the electrophotographic endless belt, the static elimination speed, etc. are determined. On the other hand, when voltage / current is applied so that charge is transferred only on the surface of the electrophotographic endless belt, it hardly depends on the internal structure or layer structure of the electrophotographic endless belt, and additives and resistance on the surface Charging and static elimination are determined only by the proportion of the control agent present.
Therefore, it is preferable from the viewpoints of transferability and cleaning properties that both the volume resistivity and the surface resistance value fall within the above ranges.

  The method for measuring the volume resistivity and surface resistance value of the electrophotographic endless belt in the present invention will be described below.

<Measuring machine>
Resistance meter: Super high resistance meter R8340A (manufactured by Advantest)
Sample box: Document box TR42 for ultra-high resistance measurement (manufactured by Advantest)
The main electrode had a diameter of 25 mm, the guard ring electrode had an inner diameter of 41 mm, and an outer diameter of 49 mm.

<Sample>
The electrophotographic endless belt is cut into a circle having a diameter of 56 mm. After cutting, an electrode is provided on one surface with a Pt—Pd vapor deposition film on one surface, and a main electrode with a diameter of 25 mm and a guard electrode with an inner diameter of 38 mm and an outer diameter of 50 mm are provided on the other surface with a Pt—Pd vapor deposition film. The Pt—Pd vapor-deposited film can be obtained by performing a vapor deposition operation for 2 minutes using mild sputtering E1030 (manufactured by Hitachi, Ltd.). The sample after the vapor deposition operation is used as a measurement sample.

<Measurement conditions>
Measurement atmosphere: 23 ° C / 55% RH
In addition, the measurement sample is allowed to stand in an environment of 23 ° C. and 55% RH for 12 hours or more in advance.
Measurement mode: Discharge 10 seconds, charge and measure 30 seconds Applied voltage: 100V
The thickness of the electrophotographic endless belt is preferably 45 to 300 μm, and more preferably 50 to 270 μm.
Further, the thickness unevenness of the electrophotographic endless belt is preferably within ± 15%. That is, the maximum thickness of the electrophotographic endless belt is preferably 115% or less of the average value, and the minimum value is preferably 85% or more of the average value.
Further, the unevenness of the thickness of the resin layer of the electrophotographic endless belt is preferably within ± 15%. That is, the maximum value of the resin layer thickness of the electrophotographic endless belt is preferably 115% or less of the average value, and the minimum value is preferably 85% or more of the average value.
In the present invention, the thickness of the electrophotographic endless belt is an average value obtained by measuring 40 points at equal intervals in the circumferential direction in the center of the electrophotographic endless belt with a dial gauge having a minimum value of 1 μm, over the entire circumference.

FIG. 3 shows an example of a schematic configuration of an intermediate transfer type color electrophotographic apparatus. Transfer of the toner image from the electrophotographic photosensitive member to the transfer material is mainly performed by a primary transfer charging member, an intermediate transfer belt, and a secondary transfer charging member.
In FIG. 3, reference numeral 1 denotes a cylindrical electrophotographic photosensitive member, which is rotationally driven in the direction of the arrow at a predetermined peripheral speed.
The surface of the electrophotographic photosensitive member 1 that is rotationally driven is uniformly charged to a predetermined positive or negative potential by the primary charging member 3, and then output from an exposure means (not shown) such as slit exposure or laser beam scanning exposure. The exposure light (image exposure light) 4 is received. The exposure light at this time is exposure light corresponding to the first color component image (for example, yellow component image) of the target color image. In this way, the first color component electrostatic latent image (yellow component electrostatic latent image) corresponding to the first color component image of the target color image is sequentially formed on the surface of the electrophotographic photoreceptor 1.
The intermediate transfer belt 11 stretched by the stretching roller 12 and the secondary transfer counter roller 13 has substantially the same peripheral speed as that of the electrophotographic photosensitive member 1 in the direction of the arrow (for example, 97 to 97% of the peripheral speed of the electrophotographic photosensitive member 1). 103%).

The first color component electrostatic latent image formed on the surface of the electrophotographic photoreceptor 1 is the first color contained in the developer carried on the first color developer carrying body (yellow developer carrying body) 5Y. The first toner image (yellow toner image) is developed by developing with toner (yellow toner). Next, the first color toner image formed and supported on the surface of the electrophotographic photosensitive member 1 is transferred to the electrophotographic photosensitive member 1 and the primary transfer charging member by the primary transfer bias from the primary transfer charging member (primary transfer charging roller) 6p. The images are sequentially primary transferred onto the surface of the intermediate transfer belt 11 passing between 6p.
The surface of the electrophotographic photosensitive member 1 after the transfer of the first color toner image is cleaned by the cleaning member 7 to remove the developer (toner) remaining after the primary transfer, and then used for image formation of the next color. The

The second color toner image (magenta toner image), the third color toner image (cyan toner image), and the fourth color toner image (black toner image) are also formed on the surface of the electrophotographic photoreceptor 1 in the same manner as the first color toner image. And are sequentially transferred onto the surface of the intermediate transfer belt 11. Thus, a synthetic toner image corresponding to the target color image is formed on the surface of the intermediate transfer belt 11. During primary transfer of the first to fourth colors, the secondary transfer charging member (secondary transfer charging roller) 6 s and the charge applying member (charge applying roller) 7 r are separated from the surface of the intermediate transfer belt 11.
The composite toner image formed on the surface of the intermediate transfer belt 11 is transferred from the transfer material supply unit to the secondary transfer counter roller 13 / intermediate transfer belt 11 and the secondary transfer charge by the secondary transfer bias from the secondary transfer charging member 6s. Secondary transfer is sequentially performed on a transfer material (paper or the like) P taken out and fed between the members 6s (contact portion) in synchronization with the rotation of the intermediate transfer belt 11.

The transfer material P, which has received the transfer of the synthetic toner image, is separated from the surface of the intermediate transfer belt 11 and introduced into the fixing means 8 to receive image fixing, thereby printing out as a color image formed product (print, copy) outside the apparatus. Be out.
The charge applying member 7r is brought into contact with the surface of the intermediate transfer belt 11 after the synthetic toner image is transferred. The charge imparting member 7r imparts a charge having a reverse polarity to that of the secondary transfer remaining developer (toner) on the surface of the intermediate transfer belt 11 to the primary transfer. The developer (toner) remaining in the secondary transfer to which a charge having a polarity opposite to that at the time of primary transfer is applied is in contact with the electrophotographic photosensitive member 1 and the intermediate transfer belt 11 and in the vicinity thereof. It is electrostatically transferred to the surface. In this way, the surface of the intermediate transfer belt 11 after the transfer of the synthetic toner image is cleaned by receiving the developer (toner) remaining after transfer. The secondary transfer residual developer (toner) transferred to the surface of the electrophotographic photosensitive member 1 is removed by the cleaning member 7 together with the primary transfer residual developer (toner) of the surface of the electrophotographic photosensitive member 1. Transfer of the remaining secondary transfer developer (toner) from the intermediate transfer belt 11 to the electrophotographic photosensitive member 1 can be performed at the same time as the primary transfer, so that the throughput is not reduced.
Further, the surface of the electrophotographic photosensitive member 1 after removal of the developer (toner) remaining after transfer by the cleaning member 7 may be subjected to charge removal processing by pre-exposure light from the pre-exposure means, but as shown in FIG. When contact charging using a roller-shaped primary charging member (primary charging roller) or the like is employed for charging the surface of the electrophotographic photosensitive member, pre-exposure is not necessarily required.

FIG. 4 shows an example of a schematic configuration of an inline type color electrophotographic apparatus. Transfer of the toner image from the electrophotographic photosensitive member to the transfer material is mainly performed by a transfer material conveyance belt and a transfer charging member.
In FIG. 4, reference numerals 1Y, 1M, 1C, and 1K denote cylindrical electrophotographic photosensitive members (first to fourth color electrophotographic photosensitive members), which are each driven to rotate at a predetermined peripheral speed in the direction of an arrow.
The surface of the first color electrophotographic photosensitive member 1Y that is rotationally driven is uniformly charged to a predetermined positive or negative potential by the primary charging member 3Y for the first color, and then subjected to slit exposure, laser beam scanning exposure, or the like. Exposure light (image exposure light) 4Y output from exposure means (not shown) is received. The exposure light 4Y is exposure light corresponding to a first color component image (for example, a yellow component image) of a target color image. Thus, a first color component electrostatic latent image (yellow component electrostatic latent image) corresponding to the first color component image of the target color image is sequentially formed on the surface of the first color electrophotographic photoreceptor 1Y.

The transfer material conveyance belt 14 stretched by the stretching roller 12 has substantially the same peripheral speed (for example, the first color to the first color) as the first to fourth color electrophotographic photoreceptors 1Y, 1M, 1C, and 1K in the direction of the arrow. The four-color electrophotographic photoreceptors 1Y, 1M, 1C, and 1K are rotated at a rotational speed of 97 to 103%. Further, the transfer material (paper or the like) P fed from the transfer material supply means is electrostatically carried (adsorbed) on the transfer material transport belt 14, and the first to fourth color electrophotographic photoreceptors 1 </ b> Y, 1M, 1C, 1K and the transfer material conveyance belt are sequentially conveyed (contact portion).
The first color component electrostatic latent image formed on the surface of the first color electrophotographic photosensitive member 1Y is developed with the first color toner contained in the developer carried on the first color developer carrying member 5Y. Thus, a first color toner image (yellow toner image) is obtained. Next, the first color toner image formed and supported on the surface of the first color electrophotographic photosensitive member 1Y is transferred by the transfer bias from the first color transfer charging member (first color transfer charging roller) 6Y. The image is sequentially transferred onto the transfer material P carried on the transfer material conveying belt 14 passing between the one-color electrophotographic photosensitive member 1Y and the first color transfer charging member 6Y.

The surface of the first color electrophotographic photoreceptor 1Y after the transfer of the first color toner image is subjected to removal of the transfer residual developer (toner) by the first color cleaning member (first color cleaning blade) 7Y. After the surface is cleaned, it is repeatedly used for forming a first color toner image.
The first color electrophotographic photosensitive member 1Y, the first color primary charging member 3Y, the first color exposure means, the first color developer carrying member 5Y, and the first color transfer charging member 6Y are grouped into the first color. This is called an image forming unit.
Second color electrophotographic photoreceptor 1M, second color primary charging member 3M, second color exposure means, second color developer carrying member 5M, second color transfer charging member 6M The image forming unit includes a third color electrophotographic photosensitive member 1C, a third color primary charging member 3C, a third color exposure unit, a third color developer carrier 5C, and a third color transfer charging member 6C. Third color image forming section, fourth color electrophotographic photosensitive member 1K, fourth color primary charging member 3K, fourth color exposure means, fourth color developer carrier 5K, fourth color transfer charge The operation of the image forming unit for the fourth color having the member 6K is the same as the operation of the image forming unit for the first color, and is carried on the transfer material transport belt 14 and the transfer material P on which the first color toner image is transferred. Second color toner image (magenta toner image), third color toner image (cyan toner image), fourth color toner image (black toner) ) Are successively transferred. In this way, a composite toner image corresponding to the target color image is formed on the transfer material P carried on the transfer material conveyance belt 14.

The transfer material P on which the synthetic toner image is formed is separated from the surface of the transfer material conveying belt 14 and introduced into the fixing means 8 to receive image fixing, thereby printing out as a color image formed product (print, copy) outside the apparatus. Be out.
Also, the first to fourth color electrophotographic photoreceptors 1Y, 1M, 1C, and 1K after the remaining developer (toner) after transfer is removed by the first to fourth color cleaning members 7Y, 7M, 7C, and 7K. The surface of the surface may be neutralized by pre-exposure light from pre-exposure means. However, as shown in FIG. 4, a roller-shaped primary charging member (primary charging roller) is used to charge the surface of the electrophotographic photosensitive member. When the contact charging used is adopted, pre-exposure is not always necessary.
In FIG. 4, reference numeral 16 denotes a separation charger for separating the transfer material from the transfer material conveying belt.

The electrophotographic endless belt of the present invention can be suitably used for the above-described intermediate transfer belt, transfer material conveyance belt, and the like.
As described above, the electrophotographic endless belt of the present invention has been described mainly with respect to the case where it is used as an intermediate transfer belt or a transfer material transport belt. However, the present invention is not limited to an intermediate transfer belt or a transfer material transport belt. The present invention can be applied to all endless belts used in electrophotographic apparatuses such as a belt, a conveying belt other than a transfer material conveying belt, a fixing belt, a developing belt, a charging belt, and a paper feeding belt.
A reinforcing member, a guide member, and a position detection member may be attached to the electrophotographic endless belt as necessary.

  Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the present invention is not limited to these. In the examples, “part” means “part by mass”.

(Example 1)
Compounding of resin composition Polyamide 12 72 parts Ethylene-glycidyl methacrylate copolymer (bond first E) 2 parts Acetylene black (Denka black powder (manufactured by Electrochemical Co., Ltd.)) 13 parts Zinc oxide 13 parts Kneading Kneading Machine: Diameter 30mm, same direction rotation meshing twin screw kneader Screw: Double type, L / D = 38
Temperature of resin composition: 280 ° C
Screw rotation: 300rpm
Discharge rate: 20kg / h
The resin composition having the above composition obtained by mixing with a tumbler was kneaded with the biaxial kneader to obtain a kneaded product having a particle diameter of 2 to 3 mm.

Extrusion to Inflation The kneaded material (resin composition) having a particle diameter of 2 to 3 mm is charged into the extruder 101 adjusted to 260 to 270 ° C. from the hopper 102 of the apparatus shown in FIG. It was melted and extruded from an annular die 103 (diameter 100 mm, die gap 800 μm) to obtain a resin composition cylinder. The temperature of the resin composition at the time of extrusion was 260 ° C. when measured with the thermometer 110 and 265 ° C. when measured with a thermometer arranged near the outlet of the annular die 103. Further, the speed at which the resin composition was extruded from the annular die 103 was 1 m / min.
Subsequently, air is blown from the gas introduction path 104 to expand and expand the cylindrical body of the resin composition to form a film, which is taken at a take-up speed of 5 m / min, and is taken in a direction perpendicular to the busbar direction every 300 mm. By continuously cutting, an endless belt 1 was obtained. The enlargement ratio was 1.6.

-Adjustment of size and surface smoothness About this belt 1, size and surface smoothness were adjusted using 1 set of cylindrical types which consist of metals from which a thermal expansion coefficient differs. Aluminum having a high thermal expansion coefficient was used for the inner mold, and stainless steel having a lower thermal expansion coefficient than aluminum was used for the outer mold. The outer mold was buffed on the inner surface and finished to a mirror surface. The dimensional gap between the outer diameter of the inner mold and the inner diameter of the outer mold was 140 μm. The belt 1 was put on the inner mold, inserted into the outer mold, and heated at 220 ° C. for 5 minutes. After cooling, the belt 1 was removed from the inner mold and the outer mold and the ends were cut to obtain a “resin layer” having a diameter of 160 mm.
A meandering prevention member was attached thereto, and a black seal was attached as a position detection member.
Thus, a single layer type electrophotographic endless belt 1 was produced.

・ T-log ₁₀ η curve of resin composition, volume resistivity and surface resistance value of resin layer, and thickness of resin layer T-log ₁₀ η curve of resin composition of resin layer of electrophotographic endless belt 1 _is the _{log 10} eta range of log ₁₀ 1000~log 10 8000, the slope (Δlog _{10 η} / ΔT) exists is gradually inclined region is -0.02～0. Moreover, the temperature range of this gentle inclination area | region was 10 degreeC or more (specifically, it is 220 degreeC to 270 degreeC, and subtracted 50 degreeC).
The average volume resistivity of the resin layer of the electrophotographic endless belt 1 is 9.2 × 10 ¹⁰ Ω · cm, the maximum value / minimum value is 3.5, and the average value of the surface resistance value is 5.0 × 10. ^{The 11} Ω / □ and the maximum / minimum value were 3.3.
The average value of the resin layer thickness of the electrophotographic endless belt 1 is 100 μm, the maximum value of the thickness is 104% of the average value, and the minimum value of the thickness is 96% of the average value. It was.

(Examples 2 to 10, Comparative Examples 1 to 3)
In Example 1, the composition of the resin composition is as shown in Table 1 or 2, the conditions for kneading before extrusion (temperature of the resin composition, screw rotation and discharge speed), and conditions for extrusion (Extruder temperature and resin composition temperature) and conditions (temperatures) for adjusting the size and surface smoothness were as shown in Table 3 in the same manner as in Example 1, An electrophotographic endless belt was produced. In order, the electrophotographic endless belts 2 to 13 are used.
Table 4 shows the T-log ₁₀ η curve of the resin composition for the electrophotographic endless belts 2 to 13, the volume resistivity and surface resistance value of the resin layer, and the thickness of the resin layer.

(Evaluation of actual machine 1)
The electrophotographic endless belts 1, 3, 4, 6 to 10 and 13 are mounted as transfer material conveying belts on an in-line color electrophotographic apparatus having the configuration shown in FIG. / L) and 30 ° C. in an 80% RH environment (H / H), a two-color solid image and a halftone image were printed on 80 g / m ² paper, and the output image was evaluated.
As a result of the evaluation of the output image, when the electrophotographic endless belts 1, 3, 4 and 6 to 9 were used, there was no occurrence of transfer unevenness and transfer omission in the output image.
When the electrophotographic endless belts 10 and 13 were used, transfer unevenness and transfer omission occurred in the output image.
In addition, the electrophotographic endless belts 1, 3, 4, 6 to 10 and 13 are mounted as transfer material conveying belts on an in-line color electrophotographic apparatus having the configuration shown in FIG. At (N / N), 50,000 images were output and durability was evaluated.
As a result of the durability evaluation, no cracks or elongation occurred in the electrophotographic endless belts 1, 3, 4 and 6-13.

(Evaluation of actual machine 2)
The electrophotographic endless belts 2, 5, 10 and 12 are mounted as intermediate transfer belts on an intermediate transfer type color electrophotographic apparatus having the structure shown in FIG. 3, respectively, at 15 ° C. in a 10% RH environment (L / L) and Two-color solid images and halftone images were printed on 80 g / m ² paper at 30 ° C. and 80% RH environment (H / H), and the output images were evaluated.
As a result of the evaluation of the output image, when the electrophotographic endless belts 2, 5 and 10 were used, there was no occurrence of transfer unevenness and transfer omission in the output image.
When the electrophotographic endless belt 12 was used, transfer unevenness and transfer omission occurred in the output image.
Further, the electrophotographic endless belts 2, 5, 10 and 12 are respectively mounted as intermediate transfer belts on an intermediate transfer type color electrophotographic apparatus having the structure shown in FIG. 3, and the environment is at 23 ° C. and 50% RH (N / N). ), 50,000 images were output and durability was evaluated.
As a result of evaluation of durability, no cracks or elongation occurred in the electrophotographic endless belts 2, 5, 10 and 12.

(Summary)
The following can be said from the results of Examples and Comparative Examples.
In other words, the electrophotographic endless belts of the examples and comparative examples both have high durability because they use polyamide (nylon), and cracks and elongation occur even if 50,000 images are output. There wasn't.
However, as is clear from the comparison between the example and the comparative examples 1 and 2, the electrophotographic endless belts of the comparative examples 1 and 2 are different from the electrophotographic endless belts of the examples, and are heterocyclic containing olefin and oxygen. Since the copolymer obtained by copolymerization of the compound is not used, the thickness uniformity is inferior, and as a result, the transferability is inferior.
Further, as is clear from the comparison between Example and Comparative Example 3, the electrophotographic endless belt of Comparative Example 3 uses a copolymer obtained by copolymerization of a heterocyclic compound containing olefin and oxygen. However, unlike the electrophotographic endless belts of the examples, since the provisions of the present invention relating to the T-log ₁₀ η curve of the resin composition are not satisfied, the thickness uniformity is inferior, and as a result, the transferability is inferior. It has become.

It is a figure which shows an example of schematic structure of the apparatus which manufactures the electrophotographic endless belt which employ | adopted the inflation molding method. It is a figure which shows another example of schematic structure of the apparatus which employ | adopts an inflation molding method and manufactures the electrophotographic endless belt. 1 is a diagram illustrating an example of a schematic configuration of an intermediate transfer type color electrophotographic apparatus. FIG. 1 is a diagram illustrating an example of a schematic configuration of an inline type color electrophotographic apparatus. FIG. Is a diagram illustrating an example of a _{T-log 10} η curve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Extruder 102 Hopper 103 Annular die 104 Gas introduction path 105 Gas 106 Molded body 107 Dimensional stability guide 108 Cooling ring 109 Cutter 110 Thermometer 201 Extruder 201
202 Hopper 210 Thermometer 1 Electrophotographic photosensitive member 3 Primary charging member 4 Exposure light (image exposure light)
5 developer carrier 6 transfer charging member 7 cleaning member 8 fixing means 11 intermediate transfer belt 12 tension roller 5Y first color developer carrier 5M second color developer carrier 5C third color developer carrier 5K developer carrier for fourth color 6p primary transfer charging member 6s secondary transfer charging member 7r charge imparting member 1Y first color electrophotographic photosensitive member 1M second color electrophotographic photosensitive member 1C third color electrophotographic photosensitive member Body 1K Fourth color electrophotographic photosensitive member 3Y First color primary charging member 3M Second color primary charging member 3C Third color primary charging member 3K Fourth color primary charging member 4Y Exposure light 4M Exposure light 4C Exposure Light 4K Exposure light 6Y First color transfer charging member 6M Second color transfer charging member 6C Third color transfer charging member 6K Fourth color transfer charging member 7Y First color cleaning member 7M Second color cleaning member 7C 3rd color Cleaning member 7K for fourth color cleaning member 13 secondary transfer counter roller 14 the transfer material transport belt 16 separating charger P transfer material

Claims (19)

In an electrophotographic endless belt having a resin layer made of a resin composition containing polyamide,
The resin composition further contains a copolymer obtained by copolymerization of a heterocyclic compound containing olefin and oxygen,
The curve (T-log ₁₀ η curve) showing the relationship between the temperature (T [° C.]) of the resin composition and the common logarithm (log ₁₀ η) of melt viscosity (η [Pa · s]) is log ₁₀ 1000. A log ₁₀ η range of ˜log ₁₀ 8000 has a slow slope region with a slope (Δlog ₁₀ η / ΔT) of −0.02 to 0, and the temperature range of the slow slope region is 10 ° C. or more,
The maximum value of the thickness of the resin layer is 115% or less of the average value of the thickness of the resin layer, and the minimum value of the thickness of the resin layer is 85% of the average value of the thickness of the resin layer An electrophotographic endless belt characterized by the above.   The electrophotographic endless belt according to claim 1, wherein a ratio of the polyamide in the resin composition is 40 to 74 mass% with respect to a total mass of the resin composition.   The electrophotographic endless belt according to claim 1, wherein the olefin is ethylene.   The electrophotographic endless belt according to claim 1, wherein the heterocyclic compound containing oxygen is glycidyl methacrylate.   The electrophotographic endless belt according to claim 1, wherein the heterocyclic compound containing oxygen is maleic anhydride.   The molecule of the copolymer obtained by copolymerization of the heterocyclic compound containing olefin and oxygen is a molecule in which the unit derived from the olefin and the unit derived from the heterocyclic compound containing oxygen are linearly bonded. The electrophotographic endless belt according to any one of claims 1 to 5.   The electrophotographic endless belt according to claim 1, wherein the polyamide is at least one resin selected from the group consisting of polyamide 6 · 10, polyamide 6 · 12, polyamide 11 and polyamide 12.   The electrophotographic endless belt according to claim 1, wherein the electrophotographic endless belt is a transfer material conveying belt.   The electrophotographic endless belt according to claim 1, wherein the electrophotographic endless belt is an intermediate transfer belt. A method for producing an electrophotographic endless belt having a resin layer comprising a resin composition containing polyamide, wherein the extruder is fed from the inside of an extruder connected to the annular die via the annular die. Production of an electrophotographic endless belt comprising: a step of obtaining a cylinder of the resin composition by extruding the resin composition; and a step of forming the resin layer of the electrophotographic endless belt using the cylinder of the resin composition In the method
The resin composition further contains a copolymer obtained by copolymerization of a heterocyclic compound containing olefin and oxygen,
The curve (T-log ₁₀ η curve) showing the relationship between the temperature (T [° C.]) of the resin composition and the common logarithm (log ₁₀ η) of melt viscosity (η [Pa · s]) is log ₁₀ 1000. A log ₁₀ η range of ˜log ₁₀ 8000 has a slow slope region with a slope (Δlog ₁₀ η / ΔT) of −0.02 to 0, and the temperature range of the slow slope region is 10 ° C. or more,
The method of producing an electrophotographic endless belt, wherein the temperature of the resin composition when extruding the resin composition is within the temperature range of the gently inclined region.   The method for producing an electrophotographic endless belt according to claim 10, wherein a ratio of the polyamide in the resin composition is 40 to 74 mass% with respect to a total mass of the resin composition.   The method for producing an electrophotographic endless belt according to claim 10 or 11, wherein the olefin is ethylene.   The method for producing an electrophotographic endless belt according to any one of claims 10 to 12, wherein the heterocyclic compound containing oxygen is glycidyl methacrylate.   The method for producing an electrophotographic endless belt according to any one of claims 10 to 12, wherein the heterocyclic compound containing oxygen is maleic anhydride.   The molecule of the copolymer obtained by copolymerization of the heterocyclic compound containing olefin and oxygen is a molecule in which the unit derived from the olefin and the unit derived from the heterocyclic compound containing oxygen are linearly bonded. The method for producing an electrophotographic endless belt according to claim 10.   The electrophotographic endless belt according to any one of claims 10 to 15, wherein the polyamide is at least one resin selected from the group consisting of polyamide 6 · 10, polyamide 6 · 12, polyamide 11 and polyamide 12. Method.   The method for producing an electrophotographic endless belt according to claim 10, wherein the electrophotographic endless belt is a transfer material conveying belt.   The method for producing an electrophotographic endless belt according to claim 10, wherein the electrophotographic endless belt is an intermediate transfer belt. An electrophotographic apparatus comprising the electrophotographic endless belt according to any one of claims 1 to 9 or the electrophotographic endless belt produced by the production method according to any one of claims 10 to 18.

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