JP2001215812A - Intermediate transfer belt and method of its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intermediate transfer belt with a good mechanical characteristic, in which permanent set is small and where a bright image without any color smear can be formed over a long period of time and a method of its manufacture. SOLUTION: In the intermediate transfer belt, a 1st base material layer where conductive short fibers are contained in vulcanized rubber in a state orienting in the movement direction or width direction of the belt and a 2nd base material layer 20 where the conductive short fibers are contained in vulcanized rubber in a state orienting in a direction that is orthogonal to the orienting direction of the short fibers in the 1st base material layer 10 (the direction of the width or the movement direction of the belt) are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an intermediate transfer belt and a method for manufacturing the same.

[0002]

2. Description of the Related Art In an electrophotographic process such as a color copying machine or a facsimile, an intermediate transfer system using an intermediate transfer belt has been adopted because of a wide range of usable transfer papers. As such an intermediate transfer belt, a belt made of resin or rubber is known.

However, conventionally known intermediate transfer belts do not have sufficient mechanical properties, and permanent elongation occurs in the moving direction (rotation direction) of the belt due to long-term use. There is a problem that a color shift occurs in a formed color image and the sharpness is impaired. Further, if permanent elongation occurs in the width direction of the belt (a direction perpendicular to the moving direction), the end of such an intermediate transfer belt may be rubbed against a flange or the like and may be damaged.

In order to solve such a problem, an intermediate transfer belt as shown in the following (1) and (2) has been proposed. (1) An intermediate transfer belt made of rubber reinforced with a polyamino woven fabric (see JP-A-3-293385). (2) An intermediate transfer belt including an elastic layer having a core layer made of a woven fabric or the like (see JP-A-11-84801).

However, in the intermediate transfer belt of the above (1), the difference in electrical resistance between the rubber and the woven fabric constituting the intermediate transfer belt is excessive, and the electrical resistance in the thickness direction of the intermediate transfer belt is extremely large. However, there is a problem that the electrostatic transfer characteristics are not high and the electrostatic transfer characteristics are not good. Further, the shape of the woven fabric may appear in the formed image. Furthermore, the polyamide fibers constituting the woven fabric have high flexibility, and stress relaxation tends to occur when used for a long time. The above (2)
In the intermediate transfer belt, it is difficult to process the elastic layer having the core layer, particularly to process it into a seamless structure. Further, the effect of suppressing permanent elongation cannot be exhibited over the entire belt.

[0006]

SUMMARY OF THE INVENTION The present invention has been made based on the above circumstances. A first object of the present invention is to provide an intermediate transfer belt having good mechanical properties, small permanent elongation, and capable of forming a clear image without color shift for a long period of time. A second object of the present invention is to provide an intermediate transfer belt having a small permanent elongation in both the moving direction and the width direction of the belt. A third object of the present invention is to provide an intermediate transfer belt having suitable electric characteristics (electric resistance value).
A fourth object of the present invention is to provide a method for suitably manufacturing an intermediate transfer belt having good mechanical and electrical characteristics.

[0007]

An intermediate transfer belt according to the present invention is an intermediate transfer belt applied to an electrophotographic process, in which conductive short fibers are oriented in a moving direction or a width direction of the belt. A first base material layer contained in the vulcanized rubber, and conductive short fibers in a direction (width direction or moving direction of the belt) orthogonal to the orientation direction of the short fibers in the first base material layer. A second base material layer contained in the vulcanized rubber in an oriented state.

In the intermediate transfer belt of the present invention, the following embodiment is preferable. (1) The first base material layer, the second base material layer, and the release layer are laminated. (2) the first base material layer in which conductive short fibers are oriented in the moving direction of the belt; and the second base material layer in which conductive short fibers are oriented in the width direction of the belt. , And a release layer. (3) The conductive short fibers constituting the first base material layer and the second base material layer are made of carbon fibers. (4) Seamless structure.

In the production method of the present invention, the first base material layer in which the conductive short fibers are oriented in the moving direction of the belt and the second base layer in which the conductive short fibers are oriented in the width direction of the belt. The method of manufacturing an intermediate transfer belt of the present invention, wherein the base layer and the release layer are laminated, wherein a step of forming a release layer on the outer peripheral surface of the sleeve, Forming a second base material layer forming material layer to be vulcanized to form a second base material layer; and electrically conductive short fibers on the surface of the second base material layer forming material layer. By applying the dispersed and contained rubber paste with a doctor knife type paster, a step of forming a coating film in which the short fibers are oriented in the application direction, and by drying the coating film, Forming a first base material layer forming material layer to be vulcanized to form a first base material layer; By the use material layer and the first base layer forming material layer vulcanizing, and the release layer, the second
A step of obtaining a cylindrical laminate of the base material layer and the first base material layer, removing the cylindrical laminate from the sleeve, and inverting the inner peripheral surface and the outer peripheral surface of the cylindrical laminate. Forming a cylindrical laminated body having the surface of the first base material layer as an inner peripheral surface and the surface of the release layer as an outer peripheral surface. .

Further, in the production method of the present invention, the first base material layer in which the conductive short fibers are oriented in the moving direction of the belt, and the conductive short fibers are oriented in the width direction of the belt. A method for producing an intermediate transfer belt according to the present invention, in which a second base material layer and a release layer are laminated, wherein a material layer for forming a release layer which is vulcanized to be a release layer is formed of a sleeve. Forming a second base material layer forming material layer that is vulcanized to be a second base material layer on the surface of the release layer forming material layer; On the surface of the material layer for forming the base material layer of No. 2, the short fibers were oriented in the application direction by applying a rubber paste containing conductive short fibers dispersed therein by a doctor knife type paster. Forming a coating film in a state, and drying the coating film to form a first substrate which is vulcanized to become a first base material layer. Forming a layer forming material layer, and vulcanizing the release layer forming material layer, the second base material layer forming material layer and the first base material layer forming material layer, A step of obtaining a tubular laminate of the release layer, the second base material layer, and the first base material layer; removing the tubular laminate from the sleeve; By inverting so that the peripheral surface and the outer peripheral surface are reversed,
Forming a cylindrical laminate having the surface of the first base material layer as an inner peripheral surface and the surface of the release layer as an outer peripheral surface.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. FIG. 1 is an explanatory cross-sectional view showing an example of the layer configuration of the intermediate transfer belt of the present invention. In FIG.
, 20 is a second base material layer, and 30 is a release layer.

<First Base Material Layer> The first base material layer 10 constituting the intermediate transfer belt contains vulcanized rubber in which conductive short fibers are oriented in the moving direction of the belt. It is configured. Thereby, the effect of suppressing permanent elongation is exhibited in the moving direction of the belt, which is the orientation direction of the short fibers.

In addition, since the short fibers contained in the first base material layer 10 are conductive, electric characteristics (electric resistance) suitable for the intermediate transfer belt are exhibited. Here, “preferred electrical characteristics” of the intermediate transfer belt include a volume resistivity (ρ) of 10 ⁹ to 10 ¹² Ω−.
cm. From the viewpoint of imparting suitable electrical characteristics to the intermediate transfer belt, the volume resistivity of the first base material layer 10 containing short fibers is preferably 10 ⁴ to 10 ⁶ Ω-cm. The thickness of the first base material layer 10 is 0.1 to
It is preferably 0.6 mm, more preferably 0.1 mm.
It is 15 to 0.25 mm.

<Second Base Layer> In the second base layer 20 constituting the intermediate transfer belt, conductive short fibers are oriented in the width direction of the belt, that is, in the direction perpendicular to the moving direction. It is constituted by being contained in vulcanized rubber in a state. Thereby, the effect of suppressing permanent elongation is exhibited also in the width direction of the belt, which is the orientation direction of the short fibers.

In addition, since the short fibers contained in the second base material layer 20 are conductive, electric properties (electric resistance) suitable for the intermediate transfer belt are exhibited. From the viewpoint of imparting suitable electrical characteristics to the intermediate transfer belt, the volume resistivity of the second base material layer 20 containing short fibers is preferably 10 ⁴ to 10 ⁶ Ω-cm. The thickness of the second base material layer 20 is preferably 0.1 to 0.6 mm, and more preferably 0.15 to 0.2 mm.
5 mm.

<Short Fibers Constituting Base Layer> The length of the short fibers contained in the vulcanized rubber and constituting the base layers (the first base layer 10 and the second base layer 20) is as follows. Is 50-20
0 μm, more preferably 100 to 100 μm.
It is set to 200 μm. If the length is too short, the reinforcing effect (effect of suppressing permanent elongation) due to the orientation cannot be sufficiently exhibited. On the other hand, if the length is too long, it becomes difficult to uniformly disperse the fibers in the vulcanized rubber.

The short fiber has a fiber diameter of 5 to 2
0 μmφ, more preferably 7 to 1 μm.
0 μmφ.

First base material layer 10 and second base material layer 20
Is preferably made of carbon fiber. Such carbon fibers are not particularly limited, such as acrylic, pitch-based and rayon-based,
PAN (polyacrylonitrile) -based carbon fiber is preferable. The elastic modulus of the carbon fiber is, for example, 5 to 60 t.
/ Mm ² , preferably 5 to 30 t / mm ² .

In the first base material layer and the second base material layer, the content of short fibers is preferably 5 to 40 parts by weight, more preferably 20 to 40 parts by weight, per 100 parts by weight of the rubber component. 30 parts by weight. If this proportion is less than 5 parts by weight, the resulting intermediate transfer belt will not have good mechanical and electrical properties. On the other hand, if this proportion exceeds 40 parts by weight, the volume resistivity becomes too low to hold the voltage.

<Rubber Constituting Base Layer> The rubber constituting the base layer (the first base layer and the second base layer) is not particularly limited. For example, natural rubber and isoprene rubber , Styrene butadiene rubber, butadiene rubber, butyl rubber, ethylene propylene rubber, ethylene propylene terpolymer rubber, chloroprene rubber, chlorosulfonated polyethylene rubber, chlorinated polyethylene rubber, acrylonitrile butadiene rubber, urethane rubber, syndiotactic 1,2-polybutadiene rubber , Epichlorohydrin rubber, acrylic rubber, silicone rubber, fluorine rubber, polysulfide rubber, polynorbornene rubber, hydrogenated nitrile rubber, and the like.
More than one species can be blended and used. Of these, hydrogenated nitrile rubber and fluoro rubber are preferred.
Further, the first base material layer and the second base material layer are preferably made of the same rubber material.

<Release Layer> As a material for forming the release layer 30, there may be mentioned a conventionally known material for forming a surface layer of the intermediate transfer belt. Specifically, fluoro rubber, fluoro resin, silicone rubber, silicone resin and the like can be exemplified. Further, a general-purpose rubber or the like to which a resin powder capable of imparting a releasing effect (surface energy lowering effect) can be used can also be used.

Here, "resin powder imparting a releasing effect"
Examples of the general-purpose rubber include a fluororesin powder such as PTFE and a silicone resin powder. The “general-purpose rubber” includes a rubber constituting the base layer (the first base layer and the second base layer). , Fluorine rubber and silicone rubber. The release layer 3
As a material constituting the second base material layer 20, the same rubber material as the rubber constituting the second base material layer 20 is used from the viewpoint of improving the adhesion between the release layer 30 and the second base material layer 20. preferable.

The dynamic frictional resistance of the surface of the release layer 30 is preferably 0.7 or less, more preferably 0.5 or less.
It is particularly preferably 0.1 to 0.5. This allows
Good cleaning properties and toner filming prevention effects are imparted to the intermediate transfer belt. The thickness of the release layer 30 is preferably 5 to 50 μm, more preferably 20 to 50 μm.

According to the intermediate transfer belt of the present invention having the above-described structure, the permanent elongation in the moving direction of the belt is suppressed by the reinforcing effect of the short fibers oriented in the first base material layer 10. The permanent elongation in the width direction of the belt is suppressed by the reinforcing effect of the short fibers oriented in the second base material layer 20. As a result, no color misregistration occurs in the formed color image, and the belt end does not break due to permanent elongation in the width direction. Furthermore, since the short fibers oriented in the first base material layer 10 and the second base material layer 20 have conductivity, electric characteristics suitable for the intermediate transfer belt are exhibited.

In the intermediate transfer belt shown in FIG. 1, the short fibers in the first base material layer 10 are oriented in the direction of movement of the belt, and the short fibers in the second base material layer 20 are oriented in the width direction of the belt. Has been described, but the first
The short fibers in the base layer (inner layer) may be oriented in the width direction of the belt, and the short fibers in the second base layer may be oriented in the moving direction of the belt.

<Physical Properties of Intermediate Transfer Belt> The intermediate transfer belt of the present invention has good mechanical properties due to the reinforcing effect of short fibers oriented in each of the first base material layer and the second base material layer. are doing. The intermediate transfer belt of the present invention preferably satisfies the following physical property conditions (measured values based on JIS K6301).

(1) Tensile strength in the belt moving direction: 10 MPa or more (2) Tensile stress in the belt moving direction (3% modulus): 2 MPa or more (3) Elongation in the belt moving direction: 400% or less

From the viewpoint of securing sufficient strength as a belt, the intermediate transfer belt of the present invention preferably has a seamless structure.

<Production Method of the Present Invention> The intermediate transfer belt of the present invention having the layer structure as shown in FIG. 1 can be suitably produced by the production method of the present invention including the following steps. Hereinafter, the production method of the present invention (the first base material layer 10 in which conductive short fibers are oriented in the moving direction of the belt,
A second in which conductive short fibers are oriented in the width direction of the belt;
An example of a method for manufacturing an intermediate transfer belt in which the base layer 20 and the release layer 30 are laminated) will be described with reference to the drawings.

[1] Release Layer Forming Step: As shown in FIG. 2A, the release layer 30 is formed on the outer peripheral surface of the sleeve 40. As a method for forming the release layer 30, a material layer (release layer forming material layer) made of unvulcanized rubber is formed on the outer peripheral surface of the sleeve 40, and in this state, the release layer forming material layer is applied. The method of sulfurizing can be mentioned. Here, the sleeve 40
In order to form a release layer forming material layer on the outer peripheral surface of the rubber sheet, an unvulcanized rubber sheet may be wound around the sleeve 40 (sheet winding method), or a rubber paste prepared from the unvulcanized rubber may be used. After being applied to the outer peripheral surface of the sleeve 40 according to a conventional method, the coating may be formed by drying and removing the solvent (coating method). It is preferable to adopt the method.

[2] Step of forming the second base material layer forming material layer: As shown in FIG. 2 (2), the surface of the release layer 30 is vulcanized to form the second base material layer. (A second base material layer forming material layer 20A) is formed. The second base material layer forming material layer 20 </ b> A is configured such that the unvulcanized rubber sheet containing the oriented short fibers made of carbon fibers is aligned with the orientation direction of the short fibers and the axial direction of the sleeve 40. (The width direction of the belt to be wound) so as to match with the surface of the release layer 30 (sheet winding method). Second base material layer forming material layer 20A
The unvulcanized rubber sheet used to form the rubber sheet is subjected to the following step [3] (application of rubber paste by a doctor knife type paster) and step [4] (drying of the formed coating film).
It can be manufactured by the same method as described above.

[3] Step of forming a coating film: A rubber knife formed by dispersing and containing short fibers made of carbon fibers is applied to the surface of the second base material layer forming material layer 20A formed in the above step by a doctor knife method. Is applied with a gluing device (knife coater). Thereby, a coating film of the rubber paste is formed on the surface of the second base material layer forming material layer 20A. Then, by adjusting the application speed by the size-reducing device, it is possible to bring the short fibers oriented in the application direction (the circumferential direction of the sleeve 40) in the coating film to be formed.

That is, the coating speed by the size-removing device is an important factor for orienting the short fibers. As a result of intensive studies by the present inventors, the coating speed was reduced to 50 cm / min.
With the above settings, short fibers having a length of about 50 to 200 μm could be oriented in the application direction. In addition,
The thickness of the coating film formed by one application is 5 to 100
The coating number is about 3 to 5 times. Further, the knife clearance is preferably 0.8 mm or less.

Here, the rubber paste in which short fibers made of carbon fibers are dispersed and contained can be prepared as follows. Raw rubber, carbon fiber (length about 0.5 to 12 mm) and various compounding agents are kneaded using a rubber roll or the like. As a result, the carbon fiber is cut into short fibers having a length of about 50 to 200 μm.
It is kneaded into the raw rubber together with the compounding agent. Here, the compounding amount of the carbon fiber is preferably 5 to 40 parts by weight, more preferably 20 to 30 parts by weight, based on 100 parts by weight of the raw rubber. Next, the kneaded dough obtained as described above is dissolved in a solvent. Here, the solvent can be appropriately selected from conventionally known organic solvents used when preparing a rubber paste, depending on the type of the raw rubber. Specific examples of the organic solvent include a volatile oil for rubber, toluene, methyl ethyl ketone, methyl isobutyl ketone, and the like. The solid content of the rubber paste thus prepared is 10 to 40% by weight.
It is preferred that The viscosity of the rubber paste is 50
Preferably, it is 200 poise (25 ° C.).

[4] Step of drying coating film: The coating film formed as described above is dried to remove the solvent. As a result, as shown in FIG. 2 (3), a material layer (first base material) that becomes the first base material layer by being vulcanized on the surface of the second base material layer forming material layer 20A. The layer forming material layer 10A) is formed. The first base material layer forming material layer 10A is configured to contain short fibers in a state of being oriented in the application direction (the circumferential direction of the sleeve 40).
Here, as the drying device, for example, a hot air dryer can be used. The drying conditions vary depending on the content of the organic solvent in the coating film and the like.
5 ° C. for 30 minutes at 0 ° C.

[5] Vulcanization step: The second base material layer forming material layer 20A and the first base material layer forming material layer 10A are vulcanized. As a result, as shown in FIG.
0, the second base material layer 20 in which short fibers are oriented in the axial direction of the sleeve 40 (width direction of the obtained belt), and short fibers in the circumferential direction of the sleeve (moving direction of the obtained belt). A cylindrical laminate obtained by laminating the oriented first base material layer 10 is obtained. Here, as the vulcanization method,
Hot air vulcanization (normal pressure vulcanization using a hot chamber) and the like can be exemplified. The vulcanization conditions are, for example, 150 to 180 ° C. for 5 to 30 minutes.

[6] Removal step: The cylindrical laminate formed in the above step [5], that is, the release layer 30 (inner layer)
And the second base material layer 20 and the first base material layer 10 (outer layer)
Is removed from the sleeve 40. At this time, as shown in FIG. 3 (2), the tubular laminate is removed while being inverted so that the inner peripheral surface and the outer peripheral surface are reversed. As a result, as shown in FIG.
A cylindrical laminate of (the inner layer), the second base material layer 20, and the release layer 30 (the outer layer) is obtained. In addition, the above-mentioned reversal operation is performed by forming a cylindrical laminate of the release layer 30 (the inner layer), the second base layer 20, and the first base layer 10 (the outer layer) into the sleeve 3.
It may be performed after detaching from zero.

[7] Dividing step: The cylindrical laminate obtained in this way is cut so as to be divided in the axial direction to obtain an intermediate transfer belt having a layer structure as shown in FIG. Can be Here, the surface of the release layer 30 of the obtained intermediate transfer belt is formed by transferring the state of the outer peripheral surface of the sleeve 40, so that the surface has excellent smoothness with small surface roughness.

In the above manufacturing method, the sleeve 40
After forming a release layer 30 (vulcanized rubber layer) on the outer peripheral surface of the second base material layer forming material layer 20A on the surface of the release layer 30
And a first base material layer forming material layer 10A is formed by lamination,
Although the case where these material layers (20A, 10A) are vulcanized to form a cylindrical laminate has been described, a material layer for forming a release layer (unvulcanized rubber layer) and a second base material layer are formed. After laminating a material layer for use and a material layer for forming the first base material layer,
The layers may be vulcanized to form a tubular laminate.

[0040]

Hereinafter, embodiments of the present invention will be described.
The present invention is not limited to these. In the following, “parts” means “parts by weight”.

<Example 1> [1] Preparation of rubber paste for forming release layer: 80 parts of hydrogenated NBR "Zetpol 2030L" (manufactured by Nippon Zeon Co., Ltd.) and hydrogenated NBR-polyzinc zinc methacrylate Dispersion "ZS
C2295 "(manufactured by Zeon Corporation), 20 parts, zinc oxide 5 parts, sedimentable sulfur 2 parts, FEF carbon 20 parts, and PTFE resin powder" TLP-10F-1 "(Mitsui DuPont Fluorochemical Co., Ltd.) 30 parts) and plasticizer 20
Of a mixture, 1 part of an antioxidant and 1 part of a vulcanization accelerator were kneaded using a rubber roll. Next, the kneaded dough obtained as described above is mixed with methyl ethyl ketone 80
% And methyl isobutyl ketone 20% to prepare a rubber paste (hereinafter referred to as "rubber paste [1a]"). Here, the solid content of the rubber paste [1a] was 10% by weight, and the viscosity (25 ° C.) was 50 poise.

[2] Base layer (first base layer and second base layer)
Preparation of rubber paste for forming base material layer): Hydrogenated NBR "Zet
Paul 2030L ”(manufactured by Nippon Zeon Co., Ltd.)
Hydrogenated NBR-polyzinc methacrylate dispersion "ZSC2
395 ”(manufactured by ZEON Corporation) and zinc oxide 5
Parts, 2 parts of settling sulfur, 50 parts of FEF carbon,
AN-based carbon chopped fiber "HTA-C6-
E ”(carbon fiber made by Toho Rayon, fiber diameter: 7 μmφ,
Length: 2-7mm, elasticity: 24t / mm ^Two) 30 parts
, Plasticizer 10 parts, antioxidant 1 part, and vulcanization accelerator 1
Parts were kneaded using a rubber roll. This
As a result, the carbon fiber becomes a short fiber of about 80 to 150 μm.
And was uniformly dispersed and contained in the raw rubber. Then on
The kneaded dough obtained as described above is methyl ethyl ketone
(Solvent) to disperse short fibers consisting of carbon fibers.
Rubber paste (hereinafter referred to as “staple fiber-containing rubber paste [1
b] ". ) Was prepared. Here, rubber containing short fibers
The paste [1b] has a solid content of 20% by weight and a viscosity (25 ° C.) of 1%.
It was 50 poise.

[3] Formation of a release layer: Rubber glue [1] was applied to the outer peripheral surface of a nickel sleeve (40) having an outer diameter of 158 mm and a length of 900 mm using a doctor knife type gluing apparatus.
a) A coating layer was dried and the solvent was removed to form a release layer forming material layer made of unvulcanized rubber on the outer peripheral surface of the sleeve (40). Next, the material layer for forming a release layer is vulcanized in a constant temperature chamber (hot chamber) at 150 ° C. for 10 minutes to form a 50 μm-thick release layer on the outer peripheral surface of the sleeve (40). (30) was formed.

[4] Formation of second base material layer forming material layer:
Short fiber-containing rubber paste [1b] was applied to the surface of the mandrel using a doctor knife type paster. Here, the short fibers contained in the short-fiber-containing rubber paste [1b] were oriented along the application direction (circumferential direction of the mandrel) by setting the application speed of the paster to 100 cm / min. . The coating film formed as described above is dried at 100 ° C. for 5 minutes by a hot air drier, and is detached from the mandrel, so that unvulcanized fibers containing short fibers oriented in the application direction are obtained. A rubber sheet was produced.

The unvulcanized rubber sheet containing the short fibers prepared in this manner is placed on the surface of the release layer (30) formed by the above [3]. The second base material layer forming material layer (20A) was formed by winding such that the orientation direction coincided with the axial direction of the sleeve (40).

[5] Formation of a coating film: On the surface of the second base material layer forming material layer (20A) formed by the above [4],
Short fiber-containing rubber paste [1b] was applied using a doctor knife type paster. Here, the short fiber contained in the short-fiber-containing rubber paste [1b] is oriented along the application direction (circumferential direction of the sleeve) by setting the application speed of the paster to 100 cm / min. Was completed.

[7] Formation of the first base material layer forming material layer:
Short fiber-containing rubber paste [1b] formed by the above [6]
Was dried at 100 ° C. for 5 minutes using a hot air drier to form a first base material layer forming material layer (10A).

[8] Vulcanization of the material layer for forming the base material layer: The material layers (20A, 10A) laminated on the surface of the release layer (30)
By vulcanizing A) at 150 ° C. for 10 minutes in a thermostatic oven, the release layer (30) and the thickness in which the short fibers are oriented in the axial direction of the sleeve (the width direction of the obtained belt). A 0.2 mm thick second base material layer (20) and a 0.2 mm thick first base material layer (short fibers oriented in the circumferential direction of the sleeve (moving direction of the resulting belt)). 10) was obtained.

[0049]

[9] Manufacture of intermediate transfer belt: cylindrical lamination of release layer (inner layer), second base layer, and first base layer (outer layer) formed as described above By removing the body from the sleeve while reversing the inner peripheral surface and the outer peripheral surface of the tubular laminate so that the inner peripheral surface and the outer peripheral surface are reversed, the first base material layer (inner layer) and the second base material layer And a cylindrical laminate with a release layer (outer layer). By cutting the cylindrical laminate obtained in this manner so as to divide it into two in the axial direction,
An intermediate transfer belt having a seamless structure having a layer configuration as shown in FIG. 1 was manufactured.

Example 2 [1] Preparation of Rubber Glue for Forming Release Layer: Fluorine Rubber Polymer "Viton B" (manufactured by DuPont Elastomer Co.) 100
Parts, magnesium oxide 15 parts, FEF carbon 15
Parts, 20 parts of PTFE resin powder “TLP-10F-1” (manufactured by DuPont-Mitsui Fluorochemicals), and 3 parts of polyamine were kneaded using a rubber roll. Next, the kneaded dough obtained as described above was dissolved in methyl ethyl ketone (solvent) to prepare a rubber paste for forming a release layer (hereinafter referred to as "rubber paste [2a]"). Here, the solid content of the rubber paste [2a] is 20% by weight and the viscosity (25%).
° C) was 150 poise.

[2] Preparation of rubber paste for forming base material layer: 100 parts of fluororubber polymer “Viton B” (manufactured by DuPont Elastomer Co.), 15 parts of magnesium oxide, and FEF
50 parts of carbon and PAN-based carbon chopped fiber "K223SE" (carbon fiber manufactured by Mitsubishi Chemical Corporation,
Fiber diameter: 10 μmφ, length: 4-6 mm, elastic modulus: 22
t / mm ² ) A compound consisting of 30 parts of polyamine and 3 parts of polyamine was kneaded using a rubber roll. As a result, the carbon fibers became short fibers of about 80 to 120 μm, and were uniformly dispersed and contained. Next, the kneaded dough obtained as described above is dissolved in methyl ethyl ketone (solvent), and a rubber paste containing short fibers composed of carbon fibers dispersed therein (hereinafter, referred to as rubber paste).
It is called "short fiber-containing rubber paste [2b]". ) Was prepared.
Here, the solid content of the short fiber-containing rubber paste [2b] was 20% by weight, and the viscosity (25 ° C.) was 150 poise.

[3] Manufacture of intermediate transfer belt: rubber paste [1
a) to form a release layer using a rubber paste [2a] instead of
In the same manner as in Example 1 except that the first base material layer and the second base material layer were formed using the short fiber-containing rubber paste [2b] instead of the short fiber-containing rubber paste [1b], FIG. An intermediate transfer belt having a seamless structure having the layer configuration shown in FIG. 1 was manufactured.

Comparative Example 1 A hydrogenated NBR-based intermediate transfer belt was manufactured in the same manner as in Example 1 except that no carbon fiber was used when preparing the rubber paste for forming the base material layer. did.

Comparative Example 2 A fluororubber intermediate transfer belt was manufactured in the same manner as in Example 2 except that no carbon fiber was used when preparing the rubber paste for forming the base material layer. .

Comparative Example 3 An intermediate transfer belt made of a fluororesin was prepared.

<Evaluation of Physical Properties of Intermediate Transfer Belt>
2 and the intermediate transfer belts according to Comparative Examples 1 and 2 were measured for physical properties in accordance with JIS K6301. The results are shown in Table 1 below. The physical property values of the intermediate transfer belts according to Example 1 and Example 2 were measured for the orientation direction of the short fibers in the first base material layer (10) (the moving direction of the belt).

[0057]

[Table 1]

<Electrical Characteristics of Intermediate Transfer Belt>
The volume resistivity was measured for each of the intermediate transfer belts according to Comparative Examples 1 to 2 and Comparative Examples 1 to 3 and each of the base material layers constituting these intermediate transfer belts. The results are shown in Table 2 below.

<Actual Photographic Test> Using a modified digital color copying machine equipped with each of the intermediate transfer belts according to Examples 1 and 2 and Comparative Examples 1 to 3, a color copy image is formed with a two-component developer. An actual test was performed to evaluate the sharpness (the occurrence of color shift visually observed at the outline of the image) for each of the formed images according to the following evaluation criteria. The results are shown in Table 2 below.

(Evaluation Criteria) A: No color shift is observed. B: Color shift is slightly recognized. C: Color shift is remarkably observed.

[0061]

[Table 2]

[0062]

According to the intermediate transfer belt of the present invention, the first
The permanent elongation in the moving direction or the width direction of the belt is suppressed by the reinforcing effect of the short fibers in the base material layer, and the width direction or movement of the belt is controlled by the reinforcing effect by the short fibers in the second base material layer. Permanent elongation in the direction is suppressed, and good mechanical properties are exhibited. Further, by the short fibers having conductivity,
Suitable electrical characteristics (10 ⁹ to 10 ¹² Ω-c in volume resistivity)
m) is expressed. Therefore, according to the intermediate transfer belt of the present invention, a clear image without color shift can be formed for a long period of time, and the end of the intermediate transfer belt will not be damaged by the flange or the like.

According to the production method of the present invention, an intermediate transfer belt having good mechanical and electrical properties and having a seamless structure can be suitably produced.

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view illustrating an example of a layer configuration of an intermediate transfer belt of the present invention.

FIG. 2 is an explanatory view showing a preferred example of the production method of the present invention.

FIG. 3 is an explanatory view showing a preferred example of the production method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 1st base material layer 10A 1st base material layer forming material layer 20 2nd base material layer 20A 2nd base material layer forming material layer 30 Release layer 40 Sleeve

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H032 BA09 4J002 AC011 AC031 AC061 AC071 AC081 AC091 BB151 BB181 BB241 BB271 BD121 BG041 BG091 BK001 CH041 CK021 CP031 DA016 FA046 FD016 FD116 GM01 GS00

Claims (7)

[Claims] 1. An intermediate transfer belt applied to an electrophotographic process, wherein a conductive short fiber is contained in a vulcanized rubber while being oriented in a moving direction or a width direction of the belt. A base material layer, and a second base material layer contained in the vulcanized rubber in a state in which conductive short fibers are oriented in a direction orthogonal to the orientation direction of the short fibers in the first base material layer. An intermediate transfer belt, comprising: 2. The intermediate transfer belt according to claim 1, wherein the first base material layer, the second base material layer, and a release layer are laminated. Intermediate transfer belt. 3. The intermediate transfer belt according to claim 1, wherein the first base material layer in which conductive short fibers are oriented in a moving direction of the belt; An intermediate transfer belt, wherein the second base material layer oriented in the width direction and a release layer are laminated. 4. The intermediate transfer belt according to claim 1, wherein the conductive short fibers constituting the first base material layer and the second base material layer are made of carbon. An intermediate transfer belt comprising a fiber. 5. The intermediate transfer belt according to claim 1, wherein the intermediate transfer belt has a seamless structure. 6. The method for manufacturing an intermediate transfer belt according to claim 3, wherein a step of forming a release layer on an outer peripheral surface of the sleeve, and a step of forming a release layer on the surface of the release layer. Forming a second base material layer forming material layer to be vulcanized to form a second base material layer; and electrically conductive short fibers on the surface of the second base material layer forming material layer. A step of forming a coating film in which the short fibers are oriented in the application direction by applying the dispersed and contained rubber paste with a doctor knife type sizing device, and by drying the coating film, A step of forming a first base material layer forming material layer to be vulcanized to form a first base material layer; the second base material layer forming material layer and the first base material layer forming material Vulcanizing a layer to obtain a cylindrical laminate of the release layer, the second base material layer, and the first base material layer; While removing the cylindrical laminate from the sleeve,
By inverting the inner peripheral surface and the outer peripheral surface of the cylindrical laminate so that they are reversed, the surface of the first base material layer is defined as the inner peripheral surface, and the surface of the release layer is defined as the outer peripheral surface. Forming an intermediate transfer belt. 7. The method for manufacturing an intermediate transfer belt according to claim 3, wherein a material layer for forming a release layer, which is vulcanized to be a release layer, is formed on an outer peripheral surface of a sleeve. Forming a second base material layer forming material layer which is vulcanized to be a second base material layer on the surface of the release layer forming material layer; On the surface of the base material layer forming material layer, by applying a rubber paste containing dispersed conductive short fibers with a doctor knife type sizing device, a state in which the short fibers are oriented in the application direction. Forming a coating film; drying the coating film to form a first base material layer forming material layer which is vulcanized to be a first base material layer; and forming the release layer. By vulcanizing the material layer, the second base material layer forming material layer and the first base material layer forming material layer, And KiHanare type layer, and the second base material layer, a step of obtaining a cylindrical laminate of a first base layer, with removed the cylindrical laminate from said sleeve,
By inverting the inner peripheral surface and the outer peripheral surface of the cylindrical laminate so that they are reversed, the surface of the first base material layer is defined as the inner peripheral surface, and the surface of the release layer is defined as the outer peripheral surface. Forming an intermediate transfer belt.