JP3278934B2 - Seamless belt - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seamless belt for use in electrophotographic copying machines, laser printers, and the like, as well as for intermediate transfer, transport, fixing, and development, as well as for photoreceptor substrates.

[0002]

2. Description of the Related Art Conventionally, endless belts, particularly seamless belts, are frequently used in intermediate transfer devices, transfer separation devices, charging devices and the like of electrophotographic copying machines and the like.
FIG. 1 is a side view of a main part of an intermediate transfer type copying machine. In the figure, 1 is a photosensitive drum, and 6 is a conductive seamless belt. An electrophotographic process unit including a charger 2, an exposure optical system 3 using a semiconductor laser or the like as a light source, a developing device 4 containing toner, and a cleaner 5 for removing residual toner is provided around the photosensitive drum 1. Are located. The conductive seamless belt 6 includes transport rollers 7, 8,
9 and is configured to move in the direction of arrow B in synchronization with the photosensitive drum rotating in the direction of arrow A.

Next, the operation will be described. First, arrow A
The surface of the photosensitive drum 1 rotating in the direction is uniformly charged by the charger 2. Next, an electrostatic latent image corresponding to an image obtained by an image reading device or the like (not shown) is formed on the photosensitive drum 1 by the optical system 3. The electrostatic latent image is developed into a toner image by the developing device 4. This toner image is electrostatically transferred to the conductive seamless belt 6 by the electrostatic transfer device 10 and the transfer roller 9
And between the pressing roller 12 and the recording paper 11.

As the conductive seamless belt, for example, a thermoplastic resin such as a polycarbonate resin or polyethylene terephthalate is blended with a conductive carbon black, and extruded into a cylindrical film using a cylindrical die. (Japanese Patent Application Laid-Open Nos. Hei 2-233765, 3-89357, and 64-26439) are known.

[0005]

SUMMARY OF THE INVENTION A seamless belt used in an electrophotographic copying machine is required to have high durability. However, in the case of a polycarbonate-based seamless belt, a crack is formed in the end face in a short time, and progresses with the passage of time, leading to breakage. In addition, in the case of intermediate transfer, transfer separation, and the like, a toner removal characteristic is also required in order to repeatedly remove toner (residual toner) not transferred to the recording paper. However, the residual toner adheres to the surface of the belt as a film as the belt is used, and cannot be easily removed (filming phenomenon). The cause of the filming phenomenon is unknown, but it is thought that the compatibility of the surface may affect it. As a resin incompatible with the toner, there is a fluorine-based resin such as polyvinylidene fluoride, but it has not been put to practical use in terms of impact resistance and durability.

Further, since the toner on the photosensitive member is transferred to the intermediate transfer belt by using the electric force by corona discharge,
A high voltage of about 1000 V is applied to the intermediate transfer belt. Since the transfer of the toner is repeatedly performed, the voltage of the intermediate transfer belt is changed from low voltage (around 10 V) to high voltage (1000 V).
(In the vicinity) is desired to have a substantially constant volume resistivity and no change in the resistance. However, in the conventional intermediate transfer belt, once a high voltage is applied, the resistance value decreases, and thereafter, even when a low voltage is applied, the resistance value does not return to the original value. When the resistance value decreases, the amount of toner transferred onto the transfer belt decreases, and problems such as deterioration of image quality and image unevenness occur.

That is, conventionally, in order to improve the above-mentioned filming phenomenon, the base polymer of the matrix is made of ethylene tetrafluoroethylene (ET) which is a fluororesin.
FE) A binary intermediate transfer belt that uses a copolymer and imparts conductivity with carbon black has been proposed. This 2
In the case of the original system, to control the volume resistivity value to a value suitable for the intermediate transfer belt, add carbon black at a high concentration,
In addition, the carbon black particles need to be dispersed very closely. However, when a high voltage (for example, 1000 V) is applied in such a dispersed state of carbon black, the carbon black particles are attracted to each other by the action of ionic conduction and form a conductive circuit, so that the volume specific resistance of the intermediate transfer belt decreases. I do. Furthermore, since this conductive circuit does not return to its original state once formed, the resistance value is kept constant and kept constant.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide an intermediate transfer belt in which the voltage dependence of the volume resistivity is small. The present inventor has conducted studies to achieve the above object. As a result, the conductive carbon black is not replaced with a fluoropolymer as a base polymer, but with a thermoplastic aromatic polycarbonate (PC) or a thermoplastic polyalkylene terephthalate (PC) as a second polymer. PAT) or PC and PAT
By selectively dispersing the mixture in a melt-kneaded mixture at a specific ratio to suppress the formation of a conductive circuit when a high voltage is applied,
The inventors have found that the voltage dependence of the resistance value can be controlled, and have reached the present invention.

That is, according to the present invention: ETF with melt flow rate less than 12g / 10min
1. 100 parts by weight of E copolymer, 2 to 20 parts by weight of PC and 3 to 25 parts by weight of conductive carbon black ETF with melt flow rate less than 12g / 10min
2. 100 parts by weight of E copolymer, 2 to 20 parts by weight of PAT, and 3 to 25 parts by weight of conductive carbon black Per 100 parts by weight of PC, 2 to 50 parts by weight of a mixture obtained by melt-kneading 5 to 100 parts by weight of PAT, 100 parts by weight of an ETFE copolymer having a melt flow rate of less than 12 g / 10 minutes, and 3 to 25 parts by weight of conductive carbon black. body products resistance 10V, the 250V and 1000V
At each applied voltage, 1 × 10 ¹ to 1 × 10 ¹³ Ω · cm
And a volume resistance value R1 at an applied voltage of 10 V;
The ratio R1 / R2 of the volume resistance R2 at 1000 V is 8
Thus, a seamless belt for an electrophotographic apparatus, which is not more than 00, is obtained.

Hereinafter, the present invention will be described specifically. (1) Ethylene tetrafluoroethylene copolymer The melt flow rate (MFR) of the ethylene tetrafluoroethylene copolymer used in the present invention is 12 g / 1.
It is preferably less than 0 min, more preferably less than 8 g / 10 min.

(2) Thermoplastic aromatic polycarbonate The aromatic polycarbonate resin used in the present invention includes:
Most of the dihydroxy compounds that constitute the carbonate ester are produced by reacting a polyhydric phenol having at least two phenolic hydroxyl groups with a carbonate precursor such as phosgene, bischloroformate, or a carbonate diester. One. As polyhydric, especially dihydric phenols, bisphenols, especially bisphenol A, are preferred.

The aromatic polycarbonate resin has a molecular weight of 22,000 to 33,000, preferably 2
4,000 to 31,000 and JIS-K
280 ° C, 2.16 kg according to 7210-1975
MFR measured by load is 0.1 to 20 g / 10
Min, preferably 1 to 10 g / 10 min. The aromatic polycarbonate resin component suitable for the present invention can be selected from commercially available products.

(3) Thermoplastic polyalkylene terephthalate [0013] Polyalkylene terephthalate (PAT), which is a thermoplastic resin used in the present invention, is characterized in that the glycol component constituting the alkylene component is ethylene glycol, triethylene glycol, 1,4-butane. Diol, hexamethylene glycol, neopentyl glycol, 2,2,4,4
-Aliphatic dioxy compounds such as tetramethylene glycol are ethylene glycol and butylene glycol, and a mixture using up to 40 mol% of another dioxy compound is also preferable.

On the other hand, the terephthalic acid component of the PAT is most preferably composed of only terephthalic acid, but may be replaced with an aromatic dicarboxylic acid, for example, isophthalic acid. PATs preferred in the present invention are polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), with PBT being particularly preferred. In addition, the melt flow rate of PBT is 3
Those having less than 0 g / 10 min are preferred, and those having less than 10 g / 10 min are particularly preferred. PET,
Various PATs, including PBT, are commercially available.

(4) Carbon Black Preferred as the carbon black used in the present invention are acetylene black, furnace black and channel black.

(5) Blending Amount The blending components and the blending amounts can be considered in the following three ways. (Formulation Example 1) 100 parts by weight of ETFE copolymer and PC2
To 20 parts by weight, preferably 2 to 10 parts by weight, more preferably 2 to 6 parts by weight and conductive carbon black 3 to 25 parts by weight.
Parts by weight, preferably 3 to 20 parts by weight. When the amount of PC is less than 2 parts by weight, the dispersion of carbon black cannot be controlled, and the voltage dependence of the resistance value increases. On the other hand, when the content exceeds 20 parts by weight, the appearance of the product is deteriorated, and the image is adversely affected.
If the carbon black is less than 3 parts by weight, the conductivity is poor,
If the amount exceeds 25 parts by weight, the appearance of the product deteriorates, and a problem of a decrease in strength occurs.

In the resin composition according to the present formulation, carbon black is selectively dispersed in PC, and this conductive PC is
It has a microdispersed configuration in a TFE copolymer. Therefore, by controlling the distance between the particles in the dispersed domain, a semiconductive resistance value can be developed. Since the conductive PC forming the dispersion domain has extremely poor conductivity as compared with carbon black alone, even when a high voltage (for example, 1000 V) is applied, adjacent dispersion domains do not move with each other, and a low voltage is applied. The same resistance value is obtained as in the case of the above.

(Formulation Example 2) 100 parts by weight of ETFE copolymer and 2 to 20 parts by weight of PAT, preferably 2 to 10 parts by weight, more preferably 2 to 6 parts by weight, and 3 to 25 parts by weight of conductive carbon black, preferably Is 3 to 20 parts by weight. P
If the AT is less than 2 parts by weight, the dispersion of carbon black cannot be controlled, and the voltage dependence of the resistance value increases. On the other hand, when the amount exceeds 20 parts by weight, the appearance of the product is deteriorated, and the image is adversely affected. If the amount of carbon black is less than 3 parts by weight, the conductivity is poor, and if it exceeds 25 parts by weight, the appearance of the product is deteriorated, and a problem of a decrease in strength occurs.

In the resin composition according to the present formulation, carbon black is selectively dispersed in PAT, and the conductive PA
T is dispersed in the ETFE copolymer in a structure that forms a partial continuous circuit. Therefore, the same conductivity can be obtained with less carbon black than in the first formulation. Since the amount of carbon added is small, even when a partial continuous circuit is formed, no decrease in resistance due to application of a high voltage is observed, and the same resistance as when a low voltage is applied is obtained.

(Formulation Example 3) P is added to 100 parts by weight of PC.
5 to 100 parts by weight, preferably 5 to 60 parts by weight, more preferably 5 to 40 parts by weight of a melt-kneaded mixture 2
50 parts by weight, preferably 2 to 30 parts by weight, more preferably 2 to 15 parts by weight, 100 parts by weight of ETFE copolymer having a melt flow rate of less than 8 g / 10 minutes, and 3 to 25 parts by weight of conductive carbon black, preferably Is 3 to 20 parts by weight. If the molten mixture of PC and PAT is less than 2 parts by weight,
Since dispersion control of carbon black cannot be performed, the voltage dependence of the resistance value increases. On the other hand, when the amount exceeds 50 parts by weight, the appearance of the product is deteriorated and the image is adversely affected. If the amount of carbon black is less than 3 parts by weight, the conductivity is poor, and if it exceeds 25 parts by weight, the appearance of the product is deteriorated, and a problem of a decrease in strength occurs.

In the resin composition of the present formulation, in the molten mixture of PC and PAT, PAT forms a continuous layer in PC, and carbon black is selectively dispersed in PAT. The dispersion structure of carbon black differs depending on the mixing ratio of PC and PAT, and the state of dispersion in the ETFE copolymer as the base polymer also changes greatly. By changing the mixing ratio of PC and PAT according to the required resistance characteristics and designing the dispersion domain of the conductive polymer, the voltage dependence of the resistance value can be reduced.

The surface resistance of the obtained seamless belt is preferably 10 ⁰ ~10 ¹³ Ω / □ range. When used as a photoreceptor substrate, 10 ⁰ ~10 ⁵ Ω / □ preferably, 10 ⁰ ~10 ³ Ω / □ is particularly preferred. When used for intermediate transfer, transportation, fixing, development and the like, it is preferably 10 ⁵ to 10 ¹³ Ω / □, and 10 ⁷ to 10 ¹²
Ω / □ is particularly preferred. The resistance in the volume direction is 1
The range is preferably from 0 ¹ to 10 ¹³ Ω · cm. When used as a photoreceptor substrate, preferably 10 ¹ ~10 ⁵ Ω · cm, particularly preferably 10 ¹ ~10 ³ Ω · cm. When used for intermediate transfer, transportation, fixing, development and the like, it is preferably 10 ⁵ to 10 ¹³ Ω · cm, and 10 ⁷ to 10
¹² Ω · cm is particularly preferred. Volume resistance value is 10 ⁷ to 10
The range of ¹² Ω · cm is a semiconductive region, and when a high voltage of about 1000 V is applied, the volume resistance value is generally reduced to 1/800 or less as compared with the resistance value at 10 V, causing image unevenness. .

Further, in the present invention, an additional component can be blended in addition to these components as long as the effects of the present invention are not significantly impaired. As the additional component and the thermoplastic resin, polypropylene, polyethylene (high density, medium density, low density, linear low density), propylene ethylene block or random copolymer, rubber or latex component, for example, ethylene / propylene copolymer Rubber, styrene-butadiene rubber, styrene-butadiene-styrene block copolymer or its hydrogenated derivatives, polybutadiene, polyisobutylene, polyamide, polyamideimide, polyacetal, polyarylate, polyphenylene ether, modified polyphenylene ether, polyimide,
Liquid crystalline polyester, polyethylene terephthalate, polysulfone, polyethersulfone, polyphenylene sulfide, polybisamidetriazole, polyetherimide, polyetheretherketone, acryl, polyvinylidene fluoride, polyvinyl fluoride, chlorotrifluoroethylene, hexafluoropropylene, par Fluoroalkyl vinyl ether copolymer, acrylic, acrylic acid alkyl ester copolymer, polyester ester copolymer, polyether ester copolymer,
One composed of one kind of a polyether amide copolymer, a polyurethane copolymer, or a mixture thereof is used. A thermosetting resin such as an epoxy resin, a melamine resin, a phenol resin, an unsaturated polyester resin, or a mixture thereof is used.

Various fillers such as calcium carbonate (heavy, light, and colloidal) talc, mica, silica, alumina, aluminum hydroxide, magnesium hydroxide, barium sulfate, zinc oxide, zeolite, wollastonite, diatomite Soil, glass fiber, glass beads, bentonite, montmorillonite, asbestos, hollow glass beads,
Graphite, molybdenum dioxide, titanium oxide, carbon fiber, aluminum fiber, stainless steel fiber, brass fiber, aluminum powder, wood powder, rice hull, graphite, metal powder, conductive metal oxide, organometallic compound, organic metal salt,
Other additives such as: antioxidants (phenolic, sulfuric, etc.), lubricants, various organic and inorganic pigments,
UV absorbers, antistatic agents, dispersants, neutralizers, foaming agents,
Examples thereof include a plasticizer, a copper damage inhibitor, a flame retardant, a crosslinking agent, and a flow improver.

The above composition may optionally contain additional components, such as a single screw extruder, a twin screw extruder, a Banbury mixer, a roll,
It can be produced using a usual kneader such as Brabender, plastograph, kneader and the like. Normally, each component is kneaded with an extruder or the like and processed after being formed into a pellet-shaped compound, but in a special case, each component is directly supplied to a molding machine, and the composition is kneaded with a molding machine. It can also be molded.

As a method for producing the seamless belt, known methods such as a continuous melt extrusion molding method, an injection molding method, a blow molding method, and an inflation film molding method can be employed. The preferred production method is continuous melt extrusion molding,
In particular, an internal cooling mandrel system or a vacuum sizing system of a downward extrusion system capable of controlling the inner diameter of the extruded tube with high precision is preferable, and an internal cooling mandrel system is most preferable.

The extruded seamless belt must have necessary conductivity, uniform thickness and mechanical strength in an unstretched state. This is because, although the mechanical strength can be expected to be improved by the stretching operation, problems such as a loss of uniformity of conductivity and a decrease in durability due to the tendency to tear in the stretching direction occur. Further, there is another problem that peeling occurs at the interface between the carbon black and the plastic, carbon is dropped, and uneven transfer occurs.

The thickness of the seamless belt is preferably 50 μm or more and 1000 μm or less, and 100 μm or more and 700 μm or less.
m or less is more preferable. When the thickness is less than 50 μm, the seamless belt is easily stretched, which causes a problem such as uneven color of an image. In addition, the withstand voltage is insufficient, and it becomes impossible to apply a voltage sufficient to impart a charge required for transfer. On the other hand, if the thickness exceeds 1000 μm, it becomes difficult to perform flexible deformation, so that a small-diameter roll cannot be driven at a uniform speed, resulting in image transfer deviation. Furthermore, since the capacitance is small, it is not possible to apply the electric charge required for transfer unless a high voltage is applied, which not only increases the cost and size of the power supply device but also discharges between peripheral device parts. Problem arises.

The seamless belt may be used as it is, or may be wound around a drum or a roll. Further, as shown in FIG. 2, for the purpose of preventing meandering and reinforcing the end surface, the inner surface end of the seamless belt having a predetermined size may be treated with heat-resistant tape 13 or silicone rubber 14.

[0030]

Next, the present invention will be described with reference to examples. Materials used in Examples and Comparative Examples are as follows. A ethylene tetrafluoroethylene copolymer (trade name “AFLON COP: C55AP” , manufactured by Asahi Glass Co., Ltd.) , melt
Flow rate 2 g / 10 min) B Thermoplastic aromatic polycarbonate (Mitsubishi Gas Chemical Co., Ltd., trade name "Iupilon E2000F" , melt flow)
Rate 1.2 g / 10 min) C thermoplastic polyalkylene terephthalate (manufactured by Mitsubishi Kasei Corporation, trade name "Novadol 5020" , melt flowre
D 1.1 g / 10 min) D 100 parts by weight of B (PC) and C (PAT) 20
E conductive carbon black (Denka Black, manufactured by Denki Kagaku Kogyo Co., Ltd.) F Conductive carbon black (Ketjen Black E, manufactured by Ketjen Black International)
C)) Experiments and evaluation methods in Examples and Comparative Examples are as follows.
It is as follows.

1. Melt flow rate Based on JIS K7210, ethylene tetrafluoroethylene copolymer temperature 300
° C, load 2.16 kg, thermoplastic aromatic polycarbonate, temperature 280
° C, load 2.16 kg thermoplastic polyalkylene terephthalate temperature 280
C. and a load of 2.16 kg.

2. Conductivity Complies with JIS K6911. Measurement was performed using a digital ultra-high resistance / micro ammeter (manufactured by Advantest: R8340A) at a measurement voltage of 10 V to 1000 V and a measurement time of 20 seconds.

3. Toner adhesion test A cellophane adhesive tape conforming to JIS Z1522 is sufficiently pressed on a sample obtained by solid development of the toner with the outer surface of the seamless belt facing upward, and is kept at about 45 ° with the surface, and is peeled off at a stretch before leaving the remaining toner. The condition is represented by the area ratio.

4. Hinge Characteristics According to JIS P8115, a seamless belt having a thickness of 150 μm is cut into a size having a width of 10 mm and a length of 80 mm according to JIS P8115.
The number of breaks was measured under the conditions of 0 ° left and right and a tensile load of 0.5 kg.

5. Durability 200mm width seamless belt, both roll diameter 25φ
mm, roll speed 100 mm / sec, belt tension 8 k
The belt was set in the apparatus shown in FIG. 2 under the conditions of g / belt full width, 25 ° C. and 55% humidity, and the state of cracking of the belt was visually observed.

Hereinafter, the present invention will be further described with reference to specific examples. (Examples 1 to 3) Examples of Formulation Example 1. With the composition shown in Table 1, the extruder is extruded below the annular die in the form of a molten tube using an extruder with an annular die of 40φ. The extruded molten tube was brought into contact with the outer surface of a cooling mandrel mounted on the same axis as the annular die via a support rod and cooled and solidified to form a seamless tube. Next, the seamless tube (the one cut to a predetermined length is a seamless belt) was pulled by the core installed in the seamless tube and the roll installed outside while maintaining the cylindrical shape. . Table 1 shows the evaluation results of the obtained belt for conductivity, toner fixation, hinge characteristics, and durability.

(Examples 4 to 6) This is an example of Formulation Example 2. Table 1 shows the evaluation results of the conductivity, the fixing property of the toner, the hinge characteristics, and the durability of the belts obtained in the same manner as in Examples 1 to 3 except for the compounding.

(Examples 7 to 11) This is an example of Formulation Example 3. Table 1 shows the evaluation results of the conductivity, the fixing property of the toner, the hinge characteristics, and the durability of the belts obtained in the same manner as in Examples 1 to 3 except for the compounding.

(Comparative Examples 1 to 3) Examples 1 to 3 except for the composition
A seamless belt was obtained in the same manner as described above. Table 1 shows the evaluation of the obtained belt for conductivity, toner fixation, hinge characteristics, and durability.

[0040]

[Table 1]

[0041]

As described above, according to the present invention,
A seamless belt having a small voltage dependency of the volume specific resistance can be obtained, which has an effect of preventing image unevenness and image shift.

[Brief description of the drawings]

FIG. 1 is a side view of a main part of an intermediate transfer type copying machine.

FIG. 2 is a perspective view of a seamless belt whose end face is reinforced.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photosensitive drum 2 charging device 3 exposure optical system 4 developing device 5 cleaner 6 conductive seamless belt 6 a inner surface 6 b outer surface 7 transport roller 8 transport roller 9 transport roller 10 electrostatic transfer device 11 recording paper 12 pressure roller 13 reinforcing Tape 14 Guide

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Yukiyoshi Komatsuzaki 8-3-1 Chuo, Ami-cho, Inashiki-gun, Ibaraki Pref. Tsukuba Research Laboratory, Mitsubishi Yuka Co., Ltd. (56) References JP-A-4-313757 (JP) (A) JP-A-2-233765 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/16 G03G 5/10 G03G 15/08 501 G03G 15/20 101

Claims (7)

(57) [Claims] 1. A composition comprising 100 parts by weight of an ethylene tetrafluoroethylene copolymer having a melt flow rate of less than 12 g / 10 minutes, 2 to 20 parts by weight of a thermoplastic aromatic polycarbonate , and 3 to 25 parts by weight of a conductive carbon black ; body volume resistance 10V, the 250V and 1000V
At each applied voltage, 1 × 10 ¹ to 1 × 10 ¹³ Ω · cm
And a volume resistance value R1 at an applied voltage of 10 V;
The ratio R1 / R2 of the volume resistance R2 at 1000 V is 8
A seamless belt for an electrophotographic apparatus, wherein the thickness is not more than 00. 2. The method according to claim 1, wherein the carbon black is a thermoplastic aromatic poly.
The thermoplastic fragrance dispersed in the carbonate
Aromatic polycarbonate is ethylene tetrafluoroethylene
2. The composition according to claim 1, which is dispersed in a copolymer.
Seamless belt for electrophotographic equipment. 3. An ethylene tetrafluoroethylene copolymer having a melt flow rate of less than 12 g / 10 minutes, 100 parts by weight, and a thermoplastic polyalkylene terephthalate of 2 to 20 parts by weight.
Parts, consists of a conductive carbon black 3-25 parts by weight, the body volume resistivity 10V, 250V and 1000V
1 × 10 ¹ to 1 × 10 ¹³ Ω · cm at each applied voltage of
, And the and the volume resistivity at an applied voltage of 10V value R1
And the ratio R1 / R2 of the volume resistance value R2 at 1000 V
Electrophotographic apparatus for sheet <br/> Muresuberuto, characterized in that but is 800 or less. 4. The carbon black is a thermoplastic polyalkyl.
Dispersed in lentephthalate and this thermoplastic
Polyalkylene terephthalate is ethylene tetrafluoro
Characterized by being dispersed in ethylene copolymer
The seamless belt for an electrophotographic apparatus according to claim 3. 5. A thermoplastic aromatic polycarbonate 100
2 to 50 parts by weight of a mixture obtained by melt-kneading 5 to 100 parts by weight of a thermoplastic polyalkylene terephthalate, 100 parts by weight of an ethylene tetrafluoroethylene copolymer having a melt flow rate of less than 12 g / 10 minutes, consists of carbon black 3-25 parts by weight, the body volume resistivity 10V, each applied voltage 250V and 1000V
A Oite ^{1 × 10 1 ~1 × 10 13} Ω · cm, and a volume resistance value R1 in sign <br/> applied voltage 10V, the ratio R1 / R2 of the volume resistivity R2 at 1000V is 800 or less A seamless belt for an electrophotographic apparatus . 6. The carbon black is a thermoplastic aromatic poly.
Carbonate and thermoplastic polyalkylene terephthalate
And the thermoplastic aromatic polydisperse
Carbonate and thermoplastic polyalkylene terephthalate
Is dispersed in ethylene tetrafluoroethylene
6. A system for an electrophotographic apparatus according to claim 5, wherein
Mooless belt. 7. A thermoplastic polyalkylene terephthalate
Is polybutylene terephthalate
An electrophotographic apparatus according to any one of claims 3 to 6.
Mooless belt.