JP2003186268A - Conductive endless belt and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conductive endless belt which is a resin belt used for image forming devices of a tandem system, intermediate transfer system, tandem intermediate transfer system, etc., and has good strength, more particularly good bending durability and creep resistance and further dimensional stability and an image forming device using the same. <P>SOLUTION: The conductive endless belt used for supplying a developer to the surface of an image forming member, such as a latent image holding member holding an electrostatic latent image on its surface to form a toner image and transferring the formed toner image to a recording medium, such as paper, in which an ethylene-vinyl alcohol copolymer or a polymer blend of the ethylene-vinyl alcohol copolymer and a thermoplastic resin is used as a base material. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the formation of an image on a latent image carrier having an electrostatic latent image on its surface in an electrostatic recording process in an electrophotographic apparatus such as a copying machine or a printer, an electrostatic recording apparatus or the like. Conductive endless belt (hereinafter also simply referred to as "belt") used when transferring a toner image formed by supplying a developer to the body surface onto a recording medium such as paper, and image formation using the same Regarding the device.

[0002]

2. Description of the Related Art Conventionally, in an electrostatic recording process in a copying machine, a printer or the like, first of all, a photoconductor (latent image carrier)
Surface is uniformly charged, an image is projected from the optical system on this photoconductor to erase the electrostatic charge on the exposed part, and then an electrostatic latent image is formed. Is used to form a toner image by electrostatically adhering toner, and the toner image is transferred to a recording medium such as paper, OHP, photographic paper, etc. to perform printing.

In this case, a color printer or a color copying machine basically prints according to the above process, but in the case of color printing, four color toners of magenta, yellow, cyan and black are used. A color tone is reproduced, and a step for superposing these toners at a predetermined ratio to obtain a required color tone is required. Several methods have been proposed for performing this step.

First, when toner is supplied onto a photoconductor to visualize an electrostatic latent image, as in the case of monochrome printing, the four colors of magenta, yellow, cyan, and black are first described. There is a multiple development system in which development is performed by sequentially stacking toner to form a color toner image on a photoconductor. According to this method, it is possible to configure the device relatively compactly, but this method has a problem that it is very difficult to control gradation and high image quality cannot be obtained.

Secondly, four photosensitive drums are provided, and the latent images of the respective drums are developed with magenta, yellow, cyan, and black toners, respectively, so that a magenta toner image, a yellow toner image, and a cyan toner image are formed. By forming four toner images of a black toner image and a black toner image, arranging the photosensitive drums on which these toner images are formed in one row, sequentially transferring each toner image to a recording medium such as paper, and superimposing it on the recording medium, There is a tandem system that reproduces a color image. In this method, although a good image can be obtained, four photosensitive drums and a charging mechanism and a developing mechanism provided for each photosensitive drum are arranged in a line, which makes the apparatus large and expensive. Becomes

FIG. 2 shows an example of the configuration of the printing unit of the tandem type image forming apparatus. A printing unit composed of the photoconductor drum 1, the charging roll 2, the developing roll 3, the developing blade 4, the toner supply roll 5 and the cleaning blade 6 is provided with 4 units corresponding to respective toners of yellow Y, magenta M, cyan C and black B. Drive rollers (drive members) 9 arranged side by side
The toner is sequentially transferred onto the paper which is circulated and conveyed by the transfer / conveyance belt 10 to form a color image.
The charging / discharging of the transfer / transport belt is performed by the charging roll 7, respectively.
And the static elimination roll 8 is used. An attraction roller (not shown) is used for charging the sheet to attract the sheet to the belt. With these measures, the generation of ozone can be suppressed. The suction roller puts the paper on the transfer / transport belt from the transport path and electrostatically attracts the transfer / transport belt. Further, the sheet separation after the transfer can be performed only by the curvature separation by lowering the transfer voltage to weaken the suction force between the sheet and the transfer / transport belt.

Materials for the transfer / conveyance belt 10 include a resistor and a dielectric, each of which has its advantages and disadvantages. Since the resistor belt holds charges for a short time, when used for tandem type transfer, charge injection in transfer is small, and voltage rise is relatively small even in continuous transfer of four colors. Also,
The electric charge is released even when it is repeatedly used for transferring the next sheet, and no electric reset is required. However, since the resistance value changes due to environmental changes, there are disadvantages that it affects the transfer efficiency and is easily affected by the thickness and width of the paper.

On the other hand, in the case of the dielectric belt, the injected charges are not spontaneously discharged, and the injection and discharge of the charges must be electrically controlled. However, since the electric charge is stably held, the paper can be securely attracted and the paper can be conveyed with high accuracy. Since the permittivity also has low dependency on temperature and humidity, the transfer process is relatively stable even to the environment. The drawback is that the transfer voltage increases because the charge is accumulated on the belt each time the transfer is repeated.

Thirdly, a recording medium such as paper is wound around a transfer drum and is rotated four times, and magenta, yellow, cyan, and black on the photoconductor are sequentially transferred to the recording medium for each revolution to reproduce a color image. There is also a transfer drum system. According to this method, a relatively high image quality can be obtained, but when the recording medium is a thick paper such as a postcard, it is difficult to wind it around the transfer drum, and the recording medium type is limited. There is.

With respect to the above-mentioned multiple development system, tandem system and transfer drum system, good image quality can be obtained, the apparatus does not become particularly large, and the type of recording medium is particularly limited. An intermediate transfer method has been proposed as a non-existent method.

That is, in this intermediate transfer system, an intermediate transfer member composed of a drum and a belt for temporarily transferring and holding the toner image on the photosensitive member is provided, and a magenta toner image and a yellow toner image are provided around the intermediate transfer member. A color image is formed on the intermediate transfer member by arranging four photoconductors on which a cyan toner image and a black toner image are formed and sequentially transferring the four color toner images onto the intermediate transfer member. The color image is transferred onto a recording medium such as paper. Therefore, since the toner images of four colors are superposed to adjust the gradation, it is possible to obtain high image quality, and it is not necessary to arrange the photoconductors in one line as in the tandem system. The size of the recording medium is not particularly limited because the recording medium does not need to be wound around a drum and the size of the recording medium is not limited. There is also a tandem intermediate transfer method that combines the tandem method and the intermediate transfer method.

As an apparatus for forming a color image by the intermediate transfer method, an image forming apparatus using an endless belt-shaped intermediate transfer member as an intermediate transfer member is illustrated in FIG.

In FIG. 3, 11 is a drum-shaped photosensitive member,
It is designed to rotate in the direction of the arrow in the figure. The photoconductor 11 is charged by the primary charger 12, then the exposed portion is erased by image exposure 13, and an electrostatic latent image corresponding to the first color component is formed on the photoconductor 11.
Further, the electrostatic latent image is developed by the developing device 41 with the magenta toner M of the first color, and the magenta toner image of the first color is formed on the photoconductor 11. Then, the toner image is circulated and driven by the driving roller (driving member) 30 to form the photosensitive member 1.
The image is transferred to the intermediate transfer member 20 that rotates while rotating in contact with 1. In this case, the transfer from the photoconductor 11 to the intermediate transfer member 20 is performed in the nip portion between the photoconductor 11 and the intermediate transfer member 20 by the primary transfer bias applied from the power supply 61 to the intermediate transfer member 20. This intermediate transfer member 2
After the first-color magenta toner image is transferred to 0, the surface of the photoconductor 11 is cleaned by the cleaning device 14, and the developing and transferring operation for the first rotation of the photoconductor 11 is completed. After that, the photoconductor rotates three times, and the developing unit 42 is rotated every revolution.
To 44 are sequentially used to sequentially form a cyan toner image of the second color, a yellow toner image of the third color, and a black toner image of the fourth color on the photoconductor 11, which are superposed and transferred to the intermediate transfer member 20 for each revolution. Then, a composite color toner image corresponding to the target color image is formed on the intermediate transfer member 20. In the apparatus shown in FIG. 3, the developing devices 41 to 44 are sequentially replaced for each revolution of the photoconductor 11 so that development with the magenta toner M, the cyan toner C, the yellow toner Y, and the black toner B is sequentially performed. Has become.

Next, the transfer roller 25 is brought into contact with the intermediate transfer member 20 on which the composite color toner image is formed, and the recording medium 26 such as paper is fed from the paper feed cassette 19 to the nip portion thereof. At the same time, the secondary transfer bias is the power source 29.
Is applied to the transfer roller 25 from the intermediate transfer member 20, and the composite color toner image is transferred from the intermediate transfer member 20 onto the recording medium 26 and heat-fixed to form a final image. After the transfer of the combined color toner image to the recording medium 26, the transfer residual toner on the surface of the intermediate transfer member 20 is removed by the cleaning device 35, and the initial state is restored to prepare for the next image formation.

Conventionally, as the endless belt-shaped intermediate transfer member 20, a semiconductive resin film belt and a rubber belt having a fiber reinforcement are mainly used. Among these, as the semi-conductive resin film belt, conventionally, one in which carbon black is blended with polycarbonate is known, but recently, based on polyalkylene terephthalate for improving the durability against bending. Resin film belt as a material (Japanese Patent Laid-Open No. 8-99374)
(Japanese Patent Laid-Open No. 11-17) or a resin film belt using thermoplastic polyimide as a base material with an improved elastic surface (JP-A-11-17.
No. 0389) has been proposed.

[0016]

A conductive endless belt used in a tandem type, an intermediate transfer type and a tandem intermediate transfer type image forming apparatus is mechanically strong enough to withstand repeated continuous use, particularly, bending durability. It is required to have creep resistance.

Although some of the semiconductive resin belts have been put to practical use so far, as the performance of the image forming apparatus has been improved, those which satisfy the above required characteristics more satisfactorily are demanded today. ing.

Therefore, an object of the present invention is to provide a resin belt used in a tandem system, an intermediate transfer system and a tandem intermediate transfer system image forming apparatus, which has good strength, particularly good bending durability and creep resistance. An object of the present invention is to provide a conductive endless belt having dimensional stability and an image forming apparatus using the same.

[0019]

Means for Solving the Problems As a result of extensive studies on various synthetic resins in order to solve the above problems, the present inventor found that ethylene-
The inventors have found that the above objects can be achieved by using a vinyl alcohol copolymer resin or a polymer blend of the ethylene-vinyl alcohol copolymer resin and a thermoplastic resin, and have completed the present invention. That is, the present invention is as shown below.

(1) A conductive endless belt by an electrostatic recording method, which is characterized by using an ethylene-vinyl alcohol copolymer resin as a base material. (2) A conductive endless belt by an electrostatic recording method, which comprises a base material of a polymer blend of an ethylene-vinyl alcohol copolymer resin and another thermoplastic resin.

(3) The electroconductive endless belt according to (2) above, wherein the thermoplastic resin is a thermoplastic elastomer. (4) The conductive endless belt according to (2), wherein the thermoplastic resin is a thermoplastic polyamide resin. (5) The conductive endless belt according to (3), wherein the thermoplastic elastomer is a thermoplastic elastomer containing a polyether component. (6) The electroconductive endless belt according to any one of (1) to (5) above, wherein the ethylene component content in the ethylene-vinyl alcohol copolymer resin is 25 to 55 mol%.

(7) The conductive endless belt according to any one of the above (1) to (6), which contains a polymer ion conductive agent. (8) The conductive endless belt according to (7), wherein the polymer ion conductive agent contains a low molecular weight ion conductive agent component. (9) The molecular weight of the polymer ion conductive agent is 700 to 3
(7) or (8), which is 0000
Conductive endless belt. (10) The content of the polymeric ionic conductive agent or the polymeric ionic conductive agent containing a low molecular ionic conductive agent component is 1 to 500 parts by weight with respect to 100 parts by weight of the base resin. The conductive endless belt according to any one of (7) to (9).

(11) A conductive endless belt according to any one of the above (1) to (10), which contains carbon black. (12) The content of the carbon black is the base resin 1
The conductive endless belt according to (11) above, wherein the amount is 1 to 100 parts by weight with respect to 00 parts by weight. (13) The conductive endless belt according to any one of (1) to (12), which has a volume resistivity of 10 ⁶ to 10 ¹³ Ω · cm.

(14) A tandem transfer / transfer method in which a recording medium held by electrostatic attraction is cyclically driven by a driving member to be conveyed to four types of image forming bodies and each toner image is sequentially transferred to the recording medium. The electroconductive endless belt according to any one of (1) to (13), which is a conveyor belt. (15) The toner image formed on the surface of the image forming body is temporarily transferred and held on the surface of the image forming body, which is disposed between the image forming body and the recording medium and is circularly driven by a driving member. The electroconductive endless belt according to any one of (1) to (13) above, which is an intermediate transfer member for transferring to.

(16) The above-mentioned (14), wherein a fitting portion for fitting with the driving member is provided on a surface of the side contacting with the driving member.
Alternatively, the conductive endless belt according to (15). (17) The conductive endless belt according to the above (16), wherein the fitting portion is a ridge that is continuously projected along the rotation direction.

(18) An image forming apparatus using the conductive endless belt according to any one of (1) to (17).

The above-mentioned conductive endless belt of the present invention has good strength, particularly good bending durability and creep resistance, and has high dimensional accuracy. Further, when the driving member and the conductive endless belt are provided with fitting portions for fitting each other, it is possible to prevent the conductive endless belt stretched around two or more shafts from shifting in the width direction with rotation. can do. Further, according to the image forming apparatus of the present invention, it is possible to provide a good image without causing a defect even after long-term use.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. The conductive endless belt is generally classified into a jointed type and a jointless type (so-called seamless belt), but any type may be used in the present invention. As described above, the conductive endless belt of the present invention can be used as a transfer member of a tandem system, an intermediate transfer system, and a tandem intermediate transfer system. When the electroconductive endless belt of the present invention is, for example, a transfer / conveyance belt shown by reference numeral 10 in FIG. 2, the toner is sequentially driven on a recording medium conveyed by being driven by a driving member such as a driving roller 9. Transferred to form a color image.

Further, when the conductive endless belt of the present invention is, for example, an intermediate transfer member indicated by reference numeral 20 in FIG. 3, it is circulated and driven by a driving member such as a driving roller 30 to form a photosensitive drum (latent image). The photosensitive drum 11 is arranged between the holding body 11 and the recording medium 26 such as paper.
The toner image formed on the surface of is temporarily transferred and held, and then transferred to the recording medium 26. The apparatus of FIG. 3 performs color printing by the intermediate transfer method as described above.

The ethylene-vinyl alcohol copolymer resin that can be used in the electroconductive endless belt of the present invention is not particularly limited, and examples thereof include Soarnol series (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) and EVAL series (Kuraray ( Commercially available from K.K.) can be typically used. The ethylene-vinyl alcohol copolymer resin has a low melt fluidity when the ethylene component content is less than 25 mol% and is difficult to mold, and when the ethylene component content exceeds 55 mol%, the creep resistance during repeated use is poor. Therefore, the ethylene component content is preferably 25 to 55 mol%. By using such an ethylene-vinyl alcohol copolymer resin as a base material of a conductive endless belt, there is no variation in resistance, strength, particularly excellent in bending resistance, and a conductive endless belt having high dimensional accuracy is obtained. To be

Further, in the present invention, a polymer blend of an ethylene-vinyl alcohol copolymer resin and another thermoplastic resin may be used, and as the other thermoplastic resin, a polyamide resin, a polyethylene resin, a polypropylene resin, Examples thereof include polybutylene terephthalate resin, polycarbonate resin and ethylene-vinyl acetate copolymer resin (elastomer). The blending ratio of the ethylene-vinyl alcohol copolymer resin in the polymer blend is preferably 10% by weight or more, and if the orientation amount is less than 10% by weight, the bending resistance may be deteriorated.

Further, it is a base material for a conductive endless belt.
Ethylene-vinyl alcohol copolymer resin or
Conductive agent added to polymer blend with thermoplastic resin
The conductivity can be imparted or adjusted. This place
In this case, the conductive agent is not particularly limited, and lauryl trimer
Tylammonium, stearyl trimethylammonium
System, octadecyltrimethylammonium, dodecylt
Limethylammonium, hexadecyltrimethylammo
Nitrogen, modified fatty acid, dimethylethylammonium
Chlorates, chlorates, borofluorides, sulphates,
Tosulfate salt, benzyl halide salt (benzyl bromide)
Quaternary ammonium, etc.)
Cationic surfactants; aliphatic sulfonic acids, higher alcohols
Sulfate ester salt, higher alcohol ethylene oxide
Anions such as salt-added sulfates and higher alcohol phosphates
ON-surfactant; zwitterionic surfactant such as betaine
Agents; higher alcohol ethylene oxide, polyethylene
Glycol fatty acid ester, polyhydric alcohol fatty acid
Antistatic agents such as non-ionic antistatic agents such as tellurium, Li
CF₂SO₂, NaClO_Four, LiBF _Four, NaCl, etc.
Metal salts of Group 1 of the periodic table of Ca;_Four)₂Circumference
Metal salts of Group 2 of the Periodic Table: and these antistatic agents
A group having active hydrogen that reacts with a cyanate (a hydrogen group,
1 or more (carboxyl group, primary or secondary amine group, etc.)
The thing which it has is mentioned. Furthermore, these and polyvalent
Alcohol (1,4-butanediol, ethylene glycol
, Polyethylene glycol, propylene glycol
Etc.) or its derivatives, or ethylene glycol
Monomethyl ether, ethylene glycol monoeth
Ion conductive agents such as complexes with ruthels; Ketjen
Conductive carbon such as black and acetylene black; S
AF, ISAF, HAF, FEF, GPF, SRF, F
Carbon for rubber such as T and MT; Color treated with oxidation
Ink carbon, pyrolytic carbon, natural graphie
G, artificial graphite, etc .; tin oxide, titanium oxide, oxidation
Metals and metal oxides such as zinc, nickel and copper; polya
Conductive poly such as nirin, polypyrrole, polyacetylene
Examples thereof include mers.

Furthermore, (A) organic polymer material, (B)
Ion-conductive polymer or copolymer, and (C)
Polymer ions consisting of a mixture of inorganic or low molecular weight organic acids
Conductive agents may be mentioned, where component (A) is poly
Acrylic acid ester, polymethacrylic acid ester, poly
Acrylonitrile, polyvinyl alcohol, polyvinyl
Acetate, polyamide, polyurethane or polyester
And the component (B) is polyether amide or
It is a polyether ester amide and component (C) is
Machine or low molecular weight organic protonic acid alkali metal, alkali
Lithium metal, zinc or ammonium salts, preferably
LiClO_Four, LiCF₃SO₃, NaClO_Four, Li
BF_Four, NaBF_Four, KBF_Four, NaCF₃SO₃, K
CIO_Four, KPF₆, KCF₃SO₃, KC_FourF₉SO
₃, Ca (ClO_Four)₂, Ca (PF₆)₂, Mg (C
10_Four)₂, Mg (CF₃SO₃)₂, Zn (Cl
O_Four) ₂, Zn (PF₆)₂Or Ca (CF₃S
O₃)₂And so on.

Among these conductive agents, a polymer ion conductive agent containing a polymer ion conductive agent or a low molecular weight ion conductive agent, or carbon black is preferable from the viewpoint of electrical durability. Among the polymeric ionic conductive agents, those having a molecular weight of 700 or more have an appropriate melt viscosity and are easy to mold, while 30,000
If the high molecular weight exceeds, the gel content tends to increase,
Since it is disadvantageous in appearance, it is particularly preferable that the molecular weight of the polymer ion conductive agent is 700 to 30,000.

When the conductive agent is a high molecular weight ion conductive agent or a high molecular weight ion conductive agent containing a low molecular weight ion conductive agent, the amount of the conductive agent added to the substrate is 1 to 100 parts by mass of the resin component. It is preferably 500 parts by mass, and in the case of carbon black, it is 1 part per 100 parts by mass of the resin component.
It is preferably from about 100 parts by mass. By containing these conductive agents, the volume resistivity of the substrate is 10 ⁶ to 10 ^6.
It can be adjusted to ¹³ Ω · cm, preferably 10 ⁷ to 10 ¹² Ω · cm.

Further, in the present invention, other functional components may be added in addition to the above-mentioned components within a range that does not impair the effects of the present invention. For example, various fillers, coupling agents, antioxidants, etc. , Lubricants, surface treatment agents, pigments, UV absorbers, antistatic agents, dispersants, neutralizing agents, foaming agents, crosslinking agents,
A compatibilizer and the like can be appropriately mixed.

The thickness of the conductive endless belt of the present invention is appropriately selected according to the form of the transfer / conveying belt or the intermediate transfer member, but is preferably 50 to 2
It is within the range of 00 μm.

Further, the conductive endless belt of the present invention has a side, which is in contact with a driving member such as the driving roller 9 in the image forming apparatus shown in FIG. 2 or the driving roller 30 shown in FIG. May be formed with a fitting portion that fits with a fitting portion (not shown) formed in the drive member. The conductive endless belt of the present invention is provided with such a fitting portion, It is possible to prevent the conductive endless belt from shifting in the width direction by fitting it into a fitting portion (not shown) provided on the driving member and running the same.

In this case, the fitting portion is not particularly limited, but as shown in FIG. 1, it is a continuous ridge along the circumferential direction (rotational direction) of the belt, which is a driving roller or the like. It is preferable that the driving member is fitted in a groove formed along the circumferential direction on the circumferential surface of the driving member.

Although FIG. 1A shows an example in which one continuous convex strip is provided as the fitting portion, this fitting portion has a large number of convex portions in the circumferential direction (rotational direction) of the belt. May be provided so as to be lined up in a line along with, and two or more fitting portions may be provided (FIG. 1B), or may be provided at the central portion in the width direction of the belt. Further, a groove extending along the circumferential direction (rotational direction) of the belt is provided as the fitting portion instead of the ridge shown in FIG. 1, and the groove is formed on the circumferential surface of the driving member such as the driving roller along the circumferential direction. You may make it fit with the said convex line.

The conductive endless belt of the present invention is not particularly limited, but the surface roughness is 10 μm or less, particularly 6 μm or less, and further 3 in terms of JIS 10-point average roughness Rz.
It is preferable that the thickness is not more than μm.

As the image forming apparatus of the present invention using the conductive endless belt of the present invention, the tandem type shown in FIG. 2, the intermediate transfer type shown in FIG. 3, or the tandem intermediate transfer type is used. However, the present invention is not limited to these. In the case of the apparatus shown in FIG. 3, a voltage can be applied from a suitable power source 61 to the drive roller or drive gear that rotates the intermediate transfer member 20 of the present invention. The application conditions such as the application of weighting alternating current can be appropriately selected.

The method for producing the electroconductive endless belt of the present invention is not particularly limited, and for example, a resin component (ethylene-vinyl alcohol copolymer resin or a polymer blend of the same and a thermoplastic resin) can be prepared by using a biaxial kneader. And a functional component such as a conductive agent are kneaded, and the obtained kneaded product is extruded and molded using a ring die. Alternatively, a powder coating method such as electrostatic coating, a solution dipping method, or a centrifugal casting method can be preferably adopted.

[0044]

EXAMPLES The present invention will be described below based on examples. Example 1 Soarnol AT4403 [trade name, Nippon Synthetic Chemical Industry Co., Ltd.
Made ethylene-vinyl alcohol copolymer resin, ethylene content 44 mol%] 100 parts by mass, Irgastat P
18 [trade name, polymer ion conductive agent manufactured by Ciba Specialty Chemicals Incorporated] and 50 parts by mass are melt-kneaded by a biaxial kneader, and the obtained kneaded product is extruded to have an inner diameter of 245 mm, Thickness 1
A conductive endless belt having dimensions of 00 μm and a width of 250 mm was obtained.

The number of times of bending resistance of this conductive endless belt was measured using a kneading fatigue resistance tester manufactured by Toyo Seiki Co., Ltd. Also, the measurement of tensile creep amount is based on JIS
According to the K7115 test method, it was carried out at a temperature of 25 ° C. for 1200 hours. Further, the volume resistivity is measured at a temperature of 20.
At a measurement voltage of 100 V at a temperature of 50 ° C. and a relative humidity of 50%, a resistance meter R8340A manufactured by ADVANTEST Co., Ltd. is used as a measuring device, and a sample chamber R127.
This was performed using the one to which 04A was connected. Further, this conductive endless belt was mounted on the tandem type image forming apparatus shown in FIG. 2 as a transfer / conveying belt, and the transfer operation was repeated to perform a durability test of 100,000 A4 sheets. At this time, the surface of the conductive endless belt was observed at any time to confirm the presence or absence of cracks. The results of this test were evaluated for image quality (whether a stable image can be obtained) and the surface condition of the belt. When there is no problem (both), "OK", when there is a problem (even with one) It was determined to be "NG". The results of these measurements and evaluations are shown in Table 1. In addition, in the table, the number of times of bending resistance was expressed as an index with the number of times of bending resistance of Comparative Example 1 being 20 times.

Example 2 Irgasat P18: In the same manner as in Example 1 except that 80 parts by weight of Perestat NC6321 (trade name, polymer ion conductive agent manufactured by Sanyo Chemical Industry Co., Ltd.) was used in place of 50 parts by weight. A conductive endless belt was produced, measured and evaluated in the same manner as in Example 1, and the results are shown in Table 1.

Examples 3 to 5 Irgasatt P18: 20 parts (Example 3), 30 parts (Example 4) or Denka Black [trade name, carbon black manufactured by Denki Kagaku Kogyo] in place of 50 parts by mass, or A conductive endless belt was produced in the same manner as in Example 1 except that 50 parts by weight (Example 5) was used, measured and evaluated in the same manner as in Example 1, and the results are shown in Table 1.

Example 6 Soarnol AT4403: 50 parts by weight and Daiamide L194 instead of 100 parts by weight of Soarnol AT4403
A conductive endless belt was prepared in the same manner as in Example 1 except that a polymer blend with 0 (trade name, thermoplastic polyamide 12 resin manufactured by Daicel Degussa) was used in the same manner as in Example 1 Measurements and evaluations were made, and the results are shown in Table 1.

Example 7 Soarnol AT4403: 80 parts by weight and Ultracene 631 instead of 100 parts by weight of Soarnol AT4403
An electrically conductive endless belt was prepared in the same manner as in Example 1 except that a polymer blend with 20 parts by mass of (trade name, ethylene-vinyl acetate copolymer elastomer manufactured by Tosoh Corporation) was used. Measurements and evaluations were carried out in the same manner, and the results are shown in Table 1.

Comparative Example 1 Soarnol AT4403: 100 parts by weight of Panlite K1300Y (trade name, thermoplastic polycarbonate resin manufactured by Teijin Chemicals Ltd.) was used in place of 100 parts by weight of Irgast.
at P18: 50 parts by mass instead of 50 parts by mass of FEF carbon [trade name, carbon black manufactured by Asahi Carbon Co., Ltd.] 30
A conductive endless belt was produced in the same manner as in Example 1 except that the parts (Example 3) were used, measured and evaluated in the same manner as in Example 1, and the results are shown in Table 1.

[0051]

[Table 1]

From the results of the above measurements and tests, it was confirmed that the electroconductive endless belts of the examples have remarkable advantages in terms of bending durability and creep resistance.

[0053]

As described above, according to the present invention, it is possible to provide a conductive endless belt which is excellent in strength, particularly in bending durability and creep resistance, and has high dimensional accuracy. Further, according to the image forming apparatus of the present invention using such a conductive endless belt of the present invention, it is possible to obtain a good image without defects even after long-term use.

[Brief description of drawings]

FIG. 1 is a cross-sectional view in the width direction of a conductive endless belt according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a transfer / transfer as an example of the image forming apparatus of the present invention.
It is a schematic diagram showing an example of a tandem-type image forming apparatus using a conveyor belt.

FIG. 3 is a schematic view showing an example of an intermediate transfer type image forming apparatus using an intermediate transfer member as another example of the image forming apparatus of the present invention.

[Explanation of symbols] 1 photoconductor drum 2 charging roll 3 developing roll 4 Development blade 5 Toner supply roll 6 cleaning blade 7 charging roll 8 Antistatic roll 9 Drive roller (drive member) 10 Transfer / transport belt 11 photoconductor 12 Primary charger 13 Image exposure 14,35 Cleaning device 19 paper cassettes 20 Intermediate transfer member 25 Transfer roller 26 recording media 29,61 power supply 30 drive roller 41, 42, 43, 44 developing device

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08L 101/00 C08L 101/00 G03G 15/01 114 G03G 15/01 114A 114B 15/16 15/16 F term (reference) 2H030 AB02 BB23 BB42 BB44 2H071 BA42 DA09 EA18 2H200 GA12 GA23 GA47 GB12 GB25 HA03 HA28 HB12 HB22 JA02 JB07 JB26 JB45 JB46 JC04 JC15 JC16 KA08 LA25 MA04 MA14 MA17 MA20 MB04 4F071 AA02 AA15 AA15X AA20 AA28 AA28X AA29 AA33 AA34 AA43 AA44 AA50 AA53 AA54 AA57 AA81 AB03 AB19 AB25 AB27 AC13 AE15 AF37 AH19 BC01 4J002 AA01X BE03W CL00X CL08Y DA037 DE196 DH006 DK006 EV256 FD11Y FD116 GM01

Claims (18)

[Claims] 1. A conductive endless belt comprising an ethylene-vinyl alcohol copolymer resin as a base material. 2. A conductive endless belt comprising a polymer blend of an ethylene-vinyl alcohol copolymer resin and another thermoplastic resin as a base material. 3. The conductive endless belt according to claim 2, wherein the thermoplastic resin is a thermoplastic elastomer. 4. The conductive endless belt according to claim 2, wherein the thermoplastic resin is a thermoplastic polyamide resin. 5. The conductive endless belt according to claim 3, wherein the thermoplastic elastomer is a thermoplastic elastomer containing a polyether component. 6. The electroconductive endless belt according to claim 1, wherein the ethylene component content of the ethylene-vinyl alcohol copolymer resin is 25 to 55 mol%. 7. The conductive endless belt according to claim 1, further comprising a polymer ion conductive agent. 8. The conductive endless belt according to claim 7, wherein the high molecular weight ionic conductive agent contains a low molecular weight ionic conductive agent component. 9. The molecular weight of the polymeric ionic conductive agent is 70.
It is 0-30000, It is characterized by the above-mentioned.
The electrically conductive endless belt according to. 10. The content of the polymeric ionic conductive agent containing the polymeric ionic conductive agent or the low molecular ionic conductive agent component,
The conductive endless belt according to claim 7, which is 1 to 500 parts by weight with respect to 100 parts by weight of the base resin. 11. The conductive endless belt according to claim 1, further comprising carbon black. 12. The conductive endless belt according to claim 11, wherein the content of the carbon black is 1 to 100 parts by weight with respect to 100 parts by weight of the base resin. 13. A volume resistivity of 10 ⁶ to 10 ¹³ Ω · cm.
The conductive endless belt according to any one of claims 1 to 12. 14. A recording medium held by electrostatic attraction,
14. A transfer / transport belt of a tandem system, which is cyclically driven by a drive member and is transported to four types of image forming bodies and sequentially transfers each toner image to the recording medium. The electroconductive endless belt according to any one of claims. 15. A toner image, which is disposed between an image forming body and a recording medium, is circularly driven by a driving member to temporarily transfer and hold the toner image formed on the surface of the image forming body on its own surface. The conductive endless belt according to any one of claims 1 to 13, which is an intermediate transfer member that transfers to a recording medium. 16. A fitting portion for fitting with the driving member is provided on a surface of the driving member which is in contact with the driving member.
The electrically conductive endless belt according to. 17. The conductive endless belt according to claim 16, wherein the fitting portion is a ridge that continuously protrudes along the rotation direction. 18. An image forming apparatus using the conductive endless belt according to claim 1. Description: