JP2001215807A - Method for manufacturing intermediate transfer belt and intermediate transfer belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method where an intermediate transfer belt provided with a receiving surface for a toner image small in surface roughness and superior in its smoothness can easily be manufactured. SOLUTION: In the method for manufacturing the intermediate transfer belt where a releasing layer 20 is formed on the receiving surface for the toner image, it is characteristic of the method to include a process to form a cylindrical laminate with the releasing layer 20 as an innermost layer on an outer periphery surface of a plating processed sleeve 50 and a process to form the cylindrical laminate with the releasing layer 20 as an outermost layer by removing the cylindrical laminate from the sleeve and turning it over so that an inner periphery surface and an outer periphery surface of the cylindrical laminate are reversed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an intermediate transfer belt applied to an electrophotographic process, and an intermediate transfer belt obtained by the method.

[0002]

2. Description of the Related Art Transfer paper (secondary transfer body) usable in electrophotographic processes such as color copying machines and fax machines.
Because of the wide selection range of the above, an intermediate transfer method using an intermediate transfer belt is employed.

In the intermediate transfer belt used in such an intermediate transfer system, from the viewpoints of improving transfer efficiency (secondary transfer efficiency) to transfer paper and improving cleanability of residual toner after transfer, etc. It is preferable to reduce surface energy on the toner image receiving surface to impart releasability.

Therefore, as a means for imparting releasability to the toner image receiving surface of the intermediate transfer belt, a technique of forming a coating film (release layer) made of a fluorine compound on the surface of the base material layer has been proposed. (See JP-A-6-222686).

Here, as a method of forming a release layer which is an outermost layer of the intermediate transfer belt, a method of winding a sheet-shaped release layer forming material around the surface of a base material layer, a method of forming a liquid release layer forming material, There is a method of applying to the surface of the base material layer.

[0006]

However, in an intermediate transfer belt having a release layer on the surface of the substrate layer, the surface state (surface roughness) of the substrate layer is determined by the surface of the release layer. And the surface of the release layer does not have smoothness. If the surface roughness of the release layer is large, the surface resistance of the release layer varies,
As a result, image density unevenness occurs in the formed image.
In order to reduce the influence of the surface state of the base material layer, the release layer may be made of a hard material. However, in such an intermediate transfer belt, the flexibility in the compression direction is low. Because of the shortage, a so-called hollow phenomenon easily occurs in the formed image. It is also conceivable that the surface of the formed release layer is smoothed by polishing (reducing the surface roughness), but the polishing is complicated and undesirably increases the number of steps.

The present invention has been made based on the above circumstances. An object of the present invention is to provide a method capable of easily manufacturing an intermediate transfer belt having a toner image receiving surface (a surface of a release layer) having a small surface roughness and excellent smoothness. Another object of the present invention is to provide a method capable of manufacturing an intermediate transfer belt having a toner image receiving surface with excellent smoothness without performing a polishing process. Another object of the present invention is to provide an intermediate transfer belt which has a toner image receiving surface with excellent smoothness and does not cause image density unevenness in a formed image. Another object of the present invention is to provide an intermediate transfer belt which has sufficient flexibility in the compression direction and does not cause a hollow phenomenon or the like in a formed image.

[0008]

The manufacturing method of the present invention is a method of manufacturing an intermediate transfer belt in which a release layer is formed on a toner image receiving surface, wherein the intermediate transfer belt has a peripheral surface of a plated sleeve. Forming a cylindrical laminate having the release layer as the innermost layer, removing the cylindrical laminate from the sleeve, and causing the inner peripheral surface and the outer peripheral surface of the cylindrical laminate to be reversed. Forming a cylindrical laminate having the release layer as the outermost layer by inversion.

In the manufacturing method of the present invention, the outer peripheral surface of the sleeve preferably has a surface roughness (Ra) of 0.5 μm or less. Further, it is preferable that the coating formed on the outer peripheral surface of the sleeve by plating is made of nickel or a nickel alloy. The intermediate transfer belt of the present invention is manufactured by the above method (the manufacturing method of the present invention).

[0010]

The surface of the release layer (toner image receiving surface) is formed using the outer peripheral surface of the sleeve smoothed by the plating process as a mold surface, so that the surface of the release layer has a small surface roughness. (For example, Ra <0.5 μm) It is excellent in smoothness. In addition, since the surface state of the release layer is not affected by the surface state of the base material layer or the like, the release layer does not need to be made of a hard substance. Has sufficient flexibility.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. <Production method of the present invention> The production method of the present invention includes a step of forming a cylindrical laminate having a release layer as the innermost layer, and a step of removing the cylindrical laminate.

FIG. 1A is a sectional view showing a sleeve used in the manufacturing method of the present invention, and FIG. 1B is FIG.
1 (3) is an explanatory view showing a mandrel (air cylinder) to which the sleeve shown in FIG. 1 is mounted, and FIG. 1 (4) is a view ( It is sectional drawing which shows the state which the sleeve shown to 1) was attached to the mandrel shown to FIG.

The sleeve 50 shown in FIG. 1 has a metal film 52 formed on a peripheral surface of a sleeve base (mother roll) 51 by plating.

The metal material constituting the metal coating 52 formed on the outer peripheral surface of the sleeve base 51 is heat-resistant,
Nickel and nickel alloys are preferred because of their excellent creep resistance and chemical stability.

The thickness (t) of the metal film 52 is 0.1 mm
The distance is set as described above, and preferably 0.1 to 0.2 mm.
If the thickness (t) is too small, the surface state of the sleeve 50 cannot be sufficiently smoothed.

The manufacturing method of the present invention is characterized in that the outer peripheral surface of the sleeve (the surface on which the metal film 52 is formed) is used as a mold surface to form the surface of the release layer. Here, metal coating 5
The surface roughness (Ra) of the surface on which No. 2 is formed is preferably 0.5 μm or less, and more preferably 0.3 μm or less. By using the sleeve 50 having such an outer peripheral surface with a small surface roughness (Ra), an intermediate transfer belt having a release layer having excellent surface smoothness can be obtained.

In the present invention, “surface roughness (Ra)” refers to a value measured under the following measurement conditions based on JIS B0601.

(Measurement conditions) Cut-off value: 4 mm Measurement length: 8 mm Measurement speed: 1 mm / s

The above-described sleeve 50 is used in a process of forming a cylindrical laminate while being mounted on a mandrel 60 shown in FIG. The mandrel 60 has an air supply port 61 and an air discharge port 62. here,
The outer diameter (Dm) of the mandrel 60 is designed to be slightly larger than the inner diameter (Ds) of the sleeve 50.

When the sleeve 50 is mounted on the mandrel 60, compressed air is supplied from an air supply port 61 of the mandrel 60. Thus, the sleeve 50 can be mounted smoothly by the action (air bearing action) of the air discharged from the air discharge port 62. Then, when the supply of the compressed air is stopped, as shown in FIG.
The inner peripheral surface of the sleeve 50 and the outer peripheral surface of the mandrel 60 come into close contact with each other.

As described above, by forming the core metal (mold) for forming the cylindrical laminated body by combining the sleeve 50 and the mandrel 60, the surface condition of the core metal deteriorates with time. (The surface roughness increases)
Only the sleeve 50 needs to be replaced, which is very advantageous in terms of manufacturing costs.

FIG. 2 is an explanatory view showing a preferred example of the manufacturing method of the present invention. According to this manufacturing method, an intermediate transfer belt in which the base layer and the release layer are laminated can be obtained. 2 (1) to 2 (3), FIG.
The illustration of the mandrel shown in (3) and (4) is omitted.

[1] Step of forming a release layer: As shown in FIG. 2A, a sleeve 50 smoothed by plating.
The release layer 20 is formed on the outer peripheral surface of the substrate. Here, the release layer 20
As a method for forming a material layer, there is a method in which a material layer made of unvulcanized rubber (a material layer for forming a release layer) is formed on the outer peripheral surface of the sleeve 50, and the material layer for forming a release layer is vulcanized in this state. Can be mentioned.

In order to form a release layer forming material layer on the outer peripheral surface of the sleeve 50, an unvulcanized rubber sheet is
0 (sheet winding method), or a rubber paste prepared from the unvulcanized rubber is applied to the outer peripheral surface of the sleeve 50 according to a conventional method, and then the coating film is dried to remove the solvent. Although a removing method (coating method) may be adopted, it is preferable to adopt the coating method in order to obtain an intermediate transfer belt having a seamless structure.

The rubber material constituting the release layer 20 includes
As a material constituting the release layer of the intermediate transfer belt, conventionally known materials can be used. Specific examples include fluorine rubber and silicone rubber. In addition, general-purpose rubber or the like to which a resin powder that imparts releasability (effect of lowering surface energy) is added can also be used.

Here, examples of the “resin powder imparting releasability” include a fluororesin powder such as PTFE and a silicone resin powder. The “general-purpose rubber” includes natural rubber, 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, polysulfide rubber, polynorbornene rubber, hydrogenated nitrile rubber and the like.

The release layer 20 preferably has a thickness of 5 to 100 μm, more preferably 20 to 50 μm.

[2] Step of Forming Base Layer: As shown in FIG. 2B, the base layer 10 is formed on the surface of the release layer 20 by lamination. Here, as a method for forming the base material layer 10, a material layer made of unvulcanized rubber (material layer for forming a base material layer) is formed on the surface of the release layer 20 by a sheet winding method or a coating method. Examples of the method include vulcanizing the layer.

The base layer 10 may be reinforced by a reinforcing material (not shown) such as a woven fabric. Here, when the base material layer 10 is reinforced by the reinforcing material, for example, the release layer 20 is used.
Forming a first material layer made of unvulcanized rubber on the surface of
A reinforcing material layer made of woven cloth or the like is wound around the surface of the first material layer, and a second material layer made of unvulcanized rubber is formed on the surface of the reinforcing material layer. A method of vulcanizing a laminate of the reinforcing material layer and the second material layer can be given. The rubber material constituting the base material layer 10 is not particularly limited, and examples thereof include the fluororubber and silicone rubber exemplified as the material constituting the release layer, and the general-purpose rubber described above.

The thickness of the base material layer 10 is preferably 0.1 to 0.6 mm, more preferably 0.15 to 0.3 mm.
5 mm.

[3] Removal step of the tubular laminate: the tubular laminate formed in the above steps, ie, the tubular laminate of the release layer 20 (inner layer) and the base material layer 10 (outer layer). The body is removed from the sleeve 50. At this time, as shown in FIG. 2 (3), 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. 2D, a cylindrical laminate having the base material layer 10 as an inner layer and the release layer 20 as an outer layer is obtained. The above-described reversing operation may be performed after the cylindrical laminate of the release layer 20 (the inner layer) and the base material layer 10 (the outer layer) is removed from the sleeve 50.

[4] Step of dividing cylindrical laminate: An intermediate transfer having a seamless structure is obtained by cutting the cylindrical laminate thus obtained so as to be divided in the axial direction, if necessary. A belt (the intermediate transfer belt of the present invention) can be obtained.

The surface of the release layer 20 of the intermediate transfer belt obtained as described above is formed using the outer peripheral surface of the sleeve 50 smoothed by plating as a mold surface. Is transferred, the surface roughness is small and the smoothness is excellent. In addition, the release layer 20 does not need to be made of a hard material, so that the obtained intermediate transfer belt has sufficient flexibility in the compression direction.

In the above, one example of the production method of the present invention has been described. However, the present invention is not limited to these, and various modifications are possible. For example, on the outer peripheral surface of the sleeve, a release layer forming material layer and a base material layer forming material layer are laminated and formed, and simultaneously vulcanized to form a laminate of the release layer and the base material layer May be. Also, the release layer 2
A step of forming an intermediate layer such as an elastic layer that imparts cushioning properties may be added between the step of forming the base layer 10 and the step of forming the base layer 10.

<Intermediate Transfer Belt of the Present Invention> The intermediate transfer belt of the present invention is obtained by the production method of the present invention. The surface roughness (Ra) of the release layer constituting the intermediate transfer belt of the present invention is preferably 0.5 μm or less,
More preferably, the thickness is 0.3 μm or less. According to the release layer having a small surface roughness (Ra), a uniform surface resistance can be obtained, and image density unevenness does not occur in a formed image. Further, the transfer residual toner on the surface can be easily cleaned.

The dynamic frictional resistance of the release layer constituting the intermediate transfer belt of the present invention is preferably 0.7 or less, more preferably 0.5 or less.

[0037]

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”.

<Preparation of Rubber Glue> [Preparation Example 1] Hydrogenated NBR "Zetpol 2030L"
(Nippon Zeon Co., Ltd.) 80 parts, hydrogenated NBR-poly zinc methacrylate dispersion "ZSC2295" (Nippon Zeon Co., Ltd.) 20 parts, zinc oxide 5 parts, sedimentable sulfur 2
Part, 20 parts of FEF carbon, and PTFE resin powder “T
LP-10F-1 "(manufactured by Du Pont-Mitsui Fluorochemicals Co., Ltd.), 20 parts of a plasticizer, 1 part of an antioxidant, and 1 part of a vulcanization accelerator are kneaded using a rubber roll. did. Next, the kneaded dough obtained as described above is dissolved in methyl ethyl ketone (solvent), and a rubber paste for forming a release layer (hereinafter, “rubber paste for forming a release layer (1A)”)
That. ) Was prepared.

[Preparation Example 2] 80 parts of hydrogenated NBR "Zetpol 2030L" (manufactured by Nippon Zeon Co., Ltd.) and hydrogenated NBR-poly zinc methacrylate dispersion "ZSC239"
5 "(manufactured by Zeon Corporation), 5 parts of zinc oxide, 2 parts of sedimentable sulfur, 20 parts of FEF carbon, 15 parts of plasticizer, 1 part of antioxidant, and vulcanization accelerator One part of the mixture was 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 (hereinafter, referred to as "base layer forming rubber paste (1B)").

[Preparation Example 3] 100 parts of a fluororubber polymer “Viton B” (manufactured by DuPont Elastomer Co.), 15 parts of magnesium oxide, 15 parts of FEF carbon, and PT
A compound consisting of 20 parts of FE resin powder "TLP-10F-1" (manufactured by Du Pont-Mitsui Fluorochemicals) and 3 parts of polyamine was 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 for forming a release layer (2A)”). .

[Preparation Example 4] A mixture of 100 parts of a fluororubber polymer "Viton B" (manufactured by DuPont Elastomer Co.), 15 parts of magnesium oxide, 15 parts of FEF carbon, and 3 parts of polyamine was prepared using a rubber roll. Kneaded. Next, the kneaded dough obtained as described above is dissolved in methyl ethyl ketone (solvent) and rubber paste
It is referred to as "rubber paste for forming base material layer (2B)". ) Was prepared.

<Example 1> (1) Fabrication of sleeve and mounting on mandrel: A 125 μm-thick film made of a nickel alloy was formed on the outer peripheral surface of a copper sleeve base (mother roll) by plating. A sleeve (50) was made. Here, the surface roughness (R) on the outer peripheral surface of the sleeve (50)
a) was 0.15 μm, which was excellent in smoothness. The sleeve (50) thus manufactured was mounted on a mandrel (60) having a configuration as shown in FIG. 1 (3).

(2) Formation of a material layer for forming a release layer: A rubber for forming a release layer is formed on the outer peripheral surface of the sleeve (50) mounted on the mandrel (60) by using a doctor knife type paster. A paste (1A) was applied, the coating was dried, and the solvent was removed to form a release layer forming material layer made of unvulcanized rubber on the surface of the sleeve (50). Then
This release layer forming material layer is vulcanized in a constant temperature chamber (hot chamber) at 150 ° C. for 10 minutes so that the outer peripheral surface of the sleeve (50) has a thickness of 50 mm.
A μm release layer (20) was formed.

(3) Formation of a base material layer: A rubber paste for forming a base material layer is formed on the surface of the release layer (20) formed as described in the above (2) by using a doctor knife type applicator. (1B) was applied, and the formed coating film was dried to form a first material layer made of unvulcanized rubber. Next, a reinforcing material layer made of a woven fabric was wound around the surface of the first material layer. Then, the base material layer forming rubber paste (1B) is applied to the surface of the reinforcing material layer using a doctor knife type paster,
By drying the formed coating film, a second material layer made of unvulcanized rubber was formed. The laminate of the first material layer, the reinforcing material layer, and the second material layer formed as described above is vulcanized at 150 ° C. for 10 minutes in a thermostatic oven, whereby the separation is performed. On the surface of the mold layer (20),
A substrate layer (10) having a thickness of 0.3 mm was formed.

(4) Production of the intermediate transfer belt: The cylindrical laminate of the release layer (inner layer) and the base material layer (outer layer) produced as described above is By removing from the sleeve while reversing the inner peripheral surface and the outer peripheral surface so as to be reversed, a cylindrical laminate having the base material layer (10) as the inner layer and the release layer (20) as the outer layer is obtained. Was. The cylindrical laminate obtained in this manner was cut into two in the axial direction to produce an intermediate transfer belt having a seamless structure.

Example 2 Rubber Glue for Forming Release Layer (1A)
Instead of using the release layer forming rubber paste (2A), a release layer is formed, and instead of the base layer forming rubber paste (1B), the base layer forming rubber paste (2B) is used. An intermediate transfer belt having a seamless structure (the intermediate transfer belt of the present invention) was manufactured in the same manner as in Example 1 except that the base material layer was formed.

The following Comparative Examples 1 and 2 are comparative examples in which a base layer was formed and then a release layer was formed on the surface thereof to form an intermediate transfer belt.

<Comparative Example 1> (1) Formation of base material layer: outer diameter 158 mm, length 900 mm
The base material layer forming rubber paste (1B) is applied to the outer peripheral surface of the mandrel using a doctor knife type paster, and the formed coating film is subjected to a drying treatment, thereby forming a second coating made of unvulcanized rubber. One material layer was formed. Next, a reinforcing material layer made of a woven fabric was wound around the surface of the first material layer. Then, the base material layer forming rubber paste (1B) is applied to the surface of the reinforcing material layer using a doctor knife type paster, and the formed coating film is subjected to a drying treatment to remove unvulcanized rubber. A second material layer was formed. By vulcanizing the laminate of the first material layer, the reinforcing material layer, and the second material layer formed as described above at 150 ° C. for 10 minutes in a constant temperature oven, A base material layer having a thickness of 0.3 mm was formed on the outer peripheral surface.

(2) Formation of release layer: Rubber paste for forming a release layer (1A) is applied to the surface of the base layer formed as described in (1) above using a doctor knife type paster. By applying and drying the coating to remove the solvent, a release layer forming material layer made of unvulcanized rubber was formed on the surface of the base material layer. Next, by vulcanizing this release layer forming material layer at 150 ° C. for 10 minutes in a thermostatic oven,
A release layer having a thickness of 50 μm was formed on the surface of the base material layer.

(3) Manufacture of the intermediate transfer belt: The cylindrical laminate having the base layer as the inner layer and the release layer as the outer layer formed as described above was removed from the mandrel. The cylindrical laminate obtained in this manner was cut into two in the axial direction to produce an intermediate transfer belt having a seamless structure.

Comparative Example 2 Rubber Paste for Forming Base Layer (1B)
, A base layer is formed using the base layer forming rubber paste (2B), and a release layer forming rubber paste (2A) is used instead of the release layer forming rubber paste (1A). An intermediate transfer belt having a seamless structure was manufactured in the same manner as in Comparative Example 1 except that a release layer was formed.

<Measurement of Surface Roughness (Ra) and Dynamic Friction Resistance of Release Layer> For each of the intermediate transfer belts according to Examples 1 and 2 and Comparative Examples 1 and 2, the surface roughness (R) of the release layer was measured.
a) and kinetic friction resistance were measured. The results are shown in Table 1 below.

<Compression Characteristics During Small Deformation>
Of each of the intermediate transfer belts according to Comparative Examples 1 and 2 and Comparative Examples 1 and 2, the compressive stress (MPa) when 50 μm of strain was applied in the compression direction using “Autograph AG-1000D” (manufactured by Shimadzu Corporation). It was measured. The results are shown in Table 1 below.
Shown in

<Actual Photographic Test> Using a modified digital color copier equipped with each of the intermediate transfer belts according to Examples 1 and 2 and Comparative Examples 1 and 2, a color copy image is formed with a two-component developer. An actual shooting test was performed, and for each of the formed images, the occurrence state of the image density unevenness and the occurrence state of the hollow defect (white spot) were evaluated according to the following criteria. The results are shown in Table 1 below.

(1) Occurrence of image density unevenness: A: Not observed at all. B: Slightly recognized on the entire image. C: Remarkably observed on the entire image.

(2) Occurrence of the hollowing phenomenon: A: No hollowing is recognized in the copied image (solid image). B: In the copied image (solid image), a few voids are recognized. C: Many voids are observed in the copied image (solid image).

[0057]

[Table 1]

[0058]

According to the production method of the present invention, it is possible to easily produce an intermediate transfer belt having a toner image receiving surface (surface of a release layer) having a small surface roughness and excellent smoothness. According to the manufacturing method of the present invention, an intermediate transfer belt having a toner image receiving surface with excellent smoothness can be easily manufactured without performing a polishing process. The intermediate transfer belt of the present invention has a toner image receiving surface (surface of the release layer) having excellent smoothness, and does not cause image density unevenness in the formed image. The intermediate transfer belt of the present invention has sufficient flexibility in the compression direction, and does not cause a hollow phenomenon or the like in a formed image.

[Brief description of the drawings]

1A is a sectional view showing a sleeve used in the manufacturing method of the present invention, FIG. 1B is a partially enlarged view of FIG.
(3) is an explanatory view showing a mandrel to which the sleeve is attached, and (4) is a cross-sectional view showing a state in which the sleeve is attached to the mandrel.

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

[Explanation of symbols]

 Reference Signs List 10 base material layer 20 release layer 50 sleeve 51 sleeve base 52 metal coating 60 mandrel 61 air supply port 62 air discharge port

Claims (4)

[Claims] 1. A method for manufacturing an intermediate transfer belt having a release layer formed on a toner image receiving surface, comprising: a cylinder having the release layer as an innermost layer on an outer peripheral surface of a plated sleeve. Forming the tubular laminate, removing the tubular laminate from the sleeve, and inverting the inner peripheral surface and the outer peripheral surface of the tubular laminate so that the inner and outer peripheral surfaces are reversed. Forming a cylindrical laminate as an outer layer. 2. The method for manufacturing an intermediate transfer belt according to claim 1, wherein the outer peripheral surface of the sleeve has a surface roughness (R).
(a) is 0.5 μm or less. 3. The method for manufacturing an intermediate transfer belt according to claim 1, wherein the coating formed on the outer peripheral surface of the sleeve by plating is made of nickel or a nickel alloy. A method for manufacturing a transfer belt. 4. An intermediate transfer belt manufactured by the method according to claim 1.