JP2001287280A - Method for manufacturing image forming belt and apparatus for performing the method - Google Patents

Abstract

(57) [Summary] (Corrected) [PROBLEMS] To provide a manufacturing method and an apparatus suitable for mass production, which can efficiently produce an image forming belt on which a silicone rubber layer is uniformly formed in a short time. A belt base material is wound around a drive roll (2) and a tension roll (3), the belt base material is run, and a curable silicone rubber composition is supplied to an outer surface of the belt base material. The composition is spread on the outer surface of the belt substrate by a first blade 4 disposed at a predetermined distance from the belt substrate in a range between an upper contact and a lower contact with the material. Next, the second blade 5 disposed at a position downstream of the position where the first blade is disposed and separated by a predetermined distance from the belt base material.
By adjusting the spread composition layer to a predetermined thickness, and then curing the composition layer formed on the outer surface of the belt substrate while running with the belt substrate, A method for producing an image forming belt, comprising:

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for manufacturing an image forming belt such as a transfer belt and a fixing belt used in an image forming apparatus such as an electrophotographic copying machine, a facsimile, and a printer.

[0002]

2. Description of the Related Art Conventionally, a transfer belt and a fixing belt used in an image forming apparatus are manufactured on an outer surface of an endless belt substrate by a method such as a spray coating method, a dipping method, and a blade coating method.

[0003] However, when the spray coating method is employed, the coating liquid is scattered so large that the coating efficiency is low, and the uncured silicone rubber (silicone rubber composition) is diluted with a solvent so as to facilitate spray coating. In this case, since toluene, xylene, heptane or the like is used as a solvent, there is a problem in terms of safety such as easy ignition. In addition, regarding production equipment, equipment such as an exhaust treatment facility for treating air containing fume-like coating liquid and a painting robot that performs strict control of the coating speed to obtain a uniform coating thickness are required. However, there is a problem that expensive and large-scale equipment is required.

[0004] When the production is performed by the dipping method, there is an advantage that the transfer and / or fixing belt can be produced with simple equipment. When the thickness of the coating layer is extremely small, a coating layer having a uniform thickness is obtained. However, when a thick coating layer having a thickness of about 100 μm is formed, there is a problem that a coating layer having a uniform thickness cannot be obtained.

In view of the above problems, a method for forming a coating layer by a blade coating method is disclosed in Japanese Patent Application Laid-Open No. Hei 7-156286. However, in this method, since only a blade (knife) for adjusting the thickness is used, it is difficult to efficiently spread the silicone rubber composition on the belt surface, and it is difficult to scrape efficiently and it takes time. Therefore, there is a problem that mass production is not possible.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an image forming belt in which a silicone rubber layer is uniformly formed, which can be efficiently manufactured in a short time, and a manufacturing method suitable for mass production, and a manufacturing method thereof. It is to provide an apparatus for performing.

[0007]

That is, the present invention relates to a method for producing an image forming belt having an endless belt substrate (hereinafter, referred to as a belt substrate) and a silicone rubber layer formed on the outer surface thereof. The belt base material is wound around a drive roll and a tension roll disposed at a position separated from the drive roll, and the belt base material is wound around the drive roll at an upper contact point with the drive roll, and the drive member is driven at a lower contact point. The belt base material is moved in a direction such that the belt base material is separated from the roll, and the curable silicone rubber composition is supplied to the outer surface of the belt base material. The curable silicone rubber composition supplied to the outer surface of the belt substrate by a first blade disposed at a predetermined distance from the belt substrate in the range of Is spread on the outer surface of the belt substrate, and then in a range between an upper contact and a lower contact of the driving roll with the belt substrate, downstream of the position where the first blade is disposed. By a second blade disposed at a position separated from the belt substrate by a predetermined distance on the side,
The layer of the silicone rubber composition spread by the first blade is adjusted to a predetermined thickness, and then the curable silicone rubber composition layer thus formed on the outer surface of the belt substrate is And a method of curing the image forming belt while running the image forming apparatus.

Further, the present invention provides an apparatus for carrying out such a method, comprising: a driving roll for running the wound belt base material; and a driving roll disposed at a position separated from the driving roll. A tension roll for holding between the driving roll and a tension roll disposed between the upper contact and the lower contact of the driving roll with the belt base material at a predetermined distance from the belt base material; A first blade for spreading the curable silicone rubber composition supplied to the outer surface of the belt substrate on the outer surface of the belt substrate, and an upper contact of the drive roll with the belt substrate. A silicone rubber spread by the first blade, which is disposed at a predetermined distance from the belt base material in a range between the lower contact and the downstream side of the first blade. A second blade for adjusting the thickness of the composition layer, and curing for curing the state in which the curable silicone rubber composition layer thus formed on the outer surface of the belt substrate travels together with the belt substrate. Means for manufacturing an endless belt for image formation.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail. The image forming belt manufactured according to the present invention is specifically used as a transfer and / or fixing belt in an image forming apparatus such as an electrophotographic copying machine, a facsimile, and a printer. The tension roll used in the present invention usually has a tension mechanism, and the belt substrate is held at a constant tension between the driving roll and the tension roll.

[0010] In a preferred embodiment, the first blade is provided in a range of 0 ° to 90 ° with a line connecting the upper contact point between the belt base material and the drive roll and the center axis of the drive roll being 0 °. . In such an angle range, the first blade is disposed at a position separated from the belt substrate by a predetermined distance. This interval is selected so as to spread the curable silicone rubber composition on the outer surface of the belt base material thicker than the cured silicone rubber layer. The second blade has a predetermined interval from the belt base material within a range of 90 ° to 180 ° with a line connecting the upper contact point between the belt base material and the drive roll and the central axis of the drive roll being 0 °. It is provided in the position which did. This second blade is a scraping blade for adjusting the thickness of the silicone rubber coating film. (See FIGS. 5 and 6).

The second blade has a generally wedge-shaped cross section, and is generally composed of a vertex of the blade and two planes extending from the acute angle of the vertex. In the present invention, a line connecting the center axis of the driving roll and the vertex of the blade is
When the angle is set to 0 °, it is preferable that the angle between the line and the scraping surface, which is one surface of the second blade, is arranged to be 0 ° to 60 ° (see FIG. 6).

[0012] The curable silicone rubber composition is usually stretched (but not limited to) horizontally between a drive roll and a tension roll, and the outer surface of a running belt substrate is
In particular, it is supplied upstream of the driving roll. The supplied composition is spread by the first blade to a thickness greater than the thickness of the cured silicone rubber layer, and then the required amount is scraped off by the second blade for scraping, and the composition layer is adjusted to a predetermined thickness. . Thereafter, the silicone rubber composition layer whose thickness has been adjusted while the belt substrate is running is cured by the curing means. The method and apparatus of the present invention will be described more specifically with reference to FIGS.

FIG. 1 is a schematic side view of a blade coating apparatus used in the present invention, and FIG. 2 is a schematic plan view thereof. Belt substrate 1 is driven by roll 2, tension roll 3
The first blade 4 and the second blade 5 are arranged at a predetermined distance from the drive roll 2.

Reference numeral 6 denotes a drive unit for the first blade 4, reference numeral 7 denotes a drive unit for the second blade 5, reference numeral 8 denotes a heater or an ultraviolet irradiation device, and reference numeral 9 denotes a drive motor.
In FIG. 2, the belt substrate 1, the driving units 6, 7 and the heating heater or the ultraviolet irradiation device 8 are omitted.

FIG. 3 shows three examples of shapes (a,
b, c), wherein the upper part is a plan view and the lower part is an end view.
Each of the three types of blades has a shape in which the central portion is thick and gradually narrows toward both ends, but is not particularly limited thereto. For example, there may be a shape in which a central portion is thick and a smooth curve is drawn toward both ends to become thin. In addition, the cross-sectional shapes are a for a circle, b for a partially cutout rectangle,
And c has the feature of being semicircular. These first blades may be arranged so that the arc surface faces the upstream side where the silicone rubber composition flows (see FIG. 5). As a result, the material supplied between the central portion of the first blade and the central portion of the belt base material is spread so as to be extruded toward both ends along the curved surface of the first blade by the rotation of the belt base material. In FIG. 5, the first blade of a shown in FIG. 4 is located at 0 °, the first blade of b is placed at 45 °, and the first blade of c is placed at 90 °. It is shown virtually. Thus, it is preferable that the first blade is provided at a position of 0 to 90 °.

As shown in FIG. 4, the scraped portion of the second blade 5 has excellent linearity in the width direction and has a sharp wedge-shaped cross section, so that the silicone rubber composition can be formed with a uniform thickness. It can be scraped and finished to a smooth surface.

FIG. 6 shows the driving roll 2 and the second blade 5
2 shows the preferred arrangement described above. In FIG. 6, reference numeral 11 denotes a second blade having a shape a shown in FIG.
°, 12 is 135 °, and 13 is 1
8 shows a state in which it is arranged at a position of 80 °, and in each case 6 ° around the apex of the sharp edge of the blade.
This shows that the arrangement is possible in an angle range of 0 °.

Examples of the material for forming the belt substrate include heat-resistant resins such as polyimide resin, polyamide resin, fluorine resin and polyester resin, and metals such as stainless steel and nickel. These heat-resistant resin belt base materials,
The thickness of the metal belt substrate is also not particularly limited, but mechanical strength, thermal conductivity, 10 to 300 in terms of heat resistance.
μ, particularly preferably 30 to 200 μ.

The curable silicone rubber composition for forming the silicone rubber layer is not particularly limited, but is preferably a liquid silicone rubber composition. The curing method is a peroxide curing type, an addition reaction curing type, An ultraviolet curing type is exemplified. The thickness of the silicone rubber layer after curing is not particularly limited, but is preferably in the range of 10 to 500 μm from the viewpoint of obtaining a better image. The surface roughness of the silicone rubber layer is Ra (center line average roughness specified in JIS B 0601)
Is preferably 10 μm or less.

For bonding the substrate and the silicone rubber layer, it is preferable to use an adhesion aid (primer). For example, a silane coupling agent or a titanium coupling agent may be applied to the substrate in advance, or the curable silicone rubber may be used. An adhesion aid may be added to the composition.

[0021]

EXAMPLES Example 1 A fixing belt was manufactured using the blade coater shown in FIGS. In this case, a stainless steel roll having a diameter of 20 mm and a length of 400 mm was used as the drive roll and the tension roll. Each of the blades used was made of stainless steel and had a length of 400 mm. The shapes of the blades were those shown as a in FIG. 3 and those of the blade 5 shown as a in FIG.
The belt base material used was a polyimide base material having a diameter of 70 mm, a width of 390 mm, and a thickness of 80 μm. Silicone rubber composition is KE19
63A / B (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) was used. As a primer, X-65-484 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) was used.

The blade 4 was set at an angle of 40 °, and the shortest gap with the belt substrate previously treated with the primer was set at 400 μm. Blade 5 is located at an angle of 135 ° and the line connecting the center of the driving roll and the vertex of the scraping blade is 0 °, and the angle between the line and the scraping surface of the scraping blade is 45 °. Adjust the gap
20mm and standby state. Drive roller rotation speed 50rpm
Then, the base material is run, and 30 g of the silicone rubber composition is supplied onto the base material by a cartridge pump (not shown).
mm (total width 350 mm). Next, after widening the gap between the blade 4 and the belt base material to 30 mm and sufficiently separating the blade 4 from the belt base material, the blade 5 was held at an angle of 135 ° to the belt base material at a forward speed of 300 mm / min. Move parallel and approach as it is, and the gap between the belt base material and the blade is 250μ
After stopping the blade 5 at the position of m, the silicone rubber composition was scraped for 10 seconds to adjust the thickness.

Next, the belt was heated by a near-infrared heater and kept at 150 ° C. for 2 minutes to cure the silicone rubber composition. As a result, a silicone rubber layer was formed on the surface. The time required for the above process was 3 minutes, which confirmed that the mass production was excellent. Thereafter, in order to improve the adhesion between the silicone rubber layer and the belt substrate, the belt was removed from the blade coater, and after-curing was performed at 200 ° C. for 2 hours in an oven. The thickness of the silicone rubber layer of the obtained belt was 246 μm, and the surface roughness of the rubber surface was R.
a was 1 μm and uniform.

The obtained endless belt was mounted on a fixing device of a laser beam printer, and full-color printing was performed. As a result, very clear printing was performed. Therefore, it was confirmed that the obtained endless belt had good performance. Was.

Example 2 A transfer and fixing belt was manufactured using the blade coater shown in FIGS. In this case, a stainless steel roll having a diameter of 20 mm and a length of 400 mm was used as the drive roll and the tension roll. All blades are made of stainless steel, 400mm long
As for the shape, the blade 4 used was shown as a in FIG. 3 and the blade 5 used the one shown as b in FIG.
The belt base material used was a stainless steel material having a diameter of 160 mm, a width of 400 mm, and a thickness of 100 μm. As the silicone rubber composition, X-65-668 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) having a volume resistivity of 5 × 10 ⁶ Ωcm was used. As a primer, X-65-196 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) was used.

The blade 4 was set at an angle of 35 °, and the shortest gap between the above-described primer-treated belt base material was
It was set to 400 μm. The blade 5 is located at an angle of 135 ° and the line connecting the center of the driving roll and the vertex of the scraping blade is O °, and the angle between the line and the scraping surface of the scraping blade is 30 °. Adjust the gap to 20
mm and the standby state. The rotation speed of the driving roll was set to 50 rpm, the substrate was run, and the silicone rubber composition was supplied to the substrate by a cartridge pump in an amount of 20 g.
m). Next, after widening the gap between the blade 4 and the belt base material to 30 mm and sufficiently moving the blade 4 away from the belt base material, the blade 2 was held at an angle of 135 ° to the endless base material belt at a forward speed of 300 mm / min. The blade 2 was stopped at a position where the gap between the belt substrate and the blade was 250 μm, and the silicon rubber composition was scraped for 10 seconds to adjust the thickness.

Next, the endless belt was heated by a near infrared heater and kept at 150 ° C. for 3 minutes to cure the silicone rubber composition. As a result, a silicone rubber layer was formed on the surface. The time required for the above steps was 4 minutes, which confirmed that the mass production was excellent. Thereafter, in order to improve the adhesive strength between the silicone rubber layer and the belt substrate, the endless belt was removed from the blade coater, and after-curing was performed at 200 ° C. for 2 hours in an oven. The thickness of the silicone rubber layer of the obtained endless belt is 47
The surface roughness of the rubber surface was uniform at 1.2 μm.

When the obtained endless belt was mounted on a transfer and fixing device of a laser beam printer and full-color printing was performed, very clear printing was achieved. It could be confirmed.

[0029]

According to the production method and apparatus of the present invention, an image forming belt having a uniform silicone rubber layer can be efficiently produced in a short time. The manufacturing method and apparatus are suitable for mass production of such belts.

[Brief description of the drawings]

FIG. 1 is a front view of an example of an apparatus for manufacturing an image forming belt of the present invention.

FIG. 2 is a plan view of the device.

FIG. 3 is a view showing the shape of a first blade, wherein the upper part is a plan view and the lower part is an end view.

FIG. 4 is a view showing the shape of a second blade, wherein the upper part is a plan view and the lower part is a sectional view.

FIG. 5 is an explanatory diagram showing an arrangement relationship between a driving roll and a first blade.

FIG. 6 is an explanatory diagram showing an arrangement relationship between a driving roll and a second blade.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Endless belt base material 2 Drive roll 3 Tension roll 4 First blade 5 Second blade 8 Heater or ultraviolet irradiation device 9 Driving motor

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B29L 29:00 B29L 29:00 (72) Inventor Tsutomu Yoneyama 2-6-1 Otemachi, Chiyoda-ku, Tokyo Shin-Etsu Chemical Co., Ltd. F-term (reference) 2H032 BA09 BA18 BA21 BA23 2H033 AA31 BA11 BA12 4F203 AA33 AH12 DA12 DB02 DC07 DK01 DL07 DL19 4F213 AA33 AA45 AC03 AD08 AG03 AG16 WA53 WA58 WB01 WF24

Claims (6)

[Claims] 1. A method for manufacturing an image forming belt having an endless belt base material and a silicone rubber layer formed on an outer surface thereof, comprising: a driving roll and a tension roll disposed at a position separated from the driving roll. Winding the belt base material, running the belt base material in a direction such that the belt base material is wound around the drive roll at an upper contact point with the drive roll and separates from the drive roll at a lower contact point, A curable silicone rubber composition is supplied to the outer surface of the material, and is disposed at a position separated by a predetermined distance from the belt substrate in a range between an upper contact and a lower contact of the driving roll with the belt substrate. The curable silicone rubber composition supplied to the outer surface of the belt base material by the first blade is spread on the outer surface of the belt base material. In a range between an upper contact and a lower contact with the belt base material, a second one disposed at a position separated by a predetermined distance from the belt base material downstream from the position where the first blade is disposed. The second blade adjusts the layer of the silicone rubber composition spread by the first blade to a predetermined thickness, and then the curable silicone rubber composition thus formed on the outer surface of the belt substrate A method for producing an image forming belt, comprising a step of curing the layer while running the layer together with the belt substrate. 2. The method according to claim 1, wherein the first blade is disposed within a range of 0 ° to 90 ° with a line connecting the center and the upper contact point of the belt base material being 0 ° about the rotation axis of the driving roll. The method according to claim 1, wherein the second blade is disposed within a range of 90 ° to 180 °. 3. When the second blade is substantially wedge-shaped having a blade-shaped apex in a cross section, and a line connecting the center axis of the drive roll and the apex of the second blade is 0 °. The manufacturing method according to claim 1, wherein the scraping surface of the second blade is disposed so as to be located within an angle of 0 ° to 60 °. 4. A drive roll for running the wound endless belt base material, and a tension roll disposed at a position separated from the drive roll for holding the belt base material between the drive roll and the drive roll. Curing provided on the outer surface of the belt substrate, which is disposed at a predetermined distance from the belt substrate in a range between an upper contact and a lower contact of the drive roll with the belt substrate. A first blade for spreading a conductive silicone rubber composition on the outer surface of the belt substrate; and a first blade in an area between an upper contact and a lower contact of the driving roll with the belt substrate. A second blower disposed at a position downstream of the blade and separated by a predetermined distance from the belt base material for adjusting the thickness of the silicone rubber composition layer spread by the first blade. And a curing means for causing the curable silicone rubber composition layer thus formed on the outer surface of the belt base material to travel together with the belt base material and to cure the same in a state. Belt manufacturing equipment. 5. The method according to claim 1, wherein the first blade is disposed within a range of 0 ° to 90 ° with a line connecting the center and an upper contact point of the belt base being 0 ° about the rotation axis of the driving roll. The manufacturing apparatus according to claim 4, wherein the second blade is disposed within a range of 90 ° to 180 °. 6. The second blade is generally wedge-shaped having a blade-shaped apex in cross section, and a line connecting the center axis of the drive roll and the apex of the second blade is defined as 0 °. The manufacturing apparatus according to claim 4, wherein the scraping surface of the second blade is disposed so as to be located within an angle of 0 ° to 60 °.