JPH04303630A - Manufacture of intermediate transfer endless belt and apparatus used therefor - Google Patents

Abstract

PURPOSE:To improve the superficial condition, circumferential length accuracy, and thickness accuracy of an intermediate transfer endless belt. CONSTITUTION:A loading roller 3 is inserted into a steel pipe 2 and on the outside of the steel pipe 2, a thermoplastic sheet 1 formed into an endless belt is put such that the inner peripheral surface thereof stands face to the outer peripheral surface of the steel pipe 2 and a first cold roller 4 treated into a mirror surface in its outer peripheral surface is arranged outside the thermoplastic sheet 1. By the loading roller 3, the steel pipe 2 is brought into press- contact with the inner peripheral surface of the thermoplastic sheet 1 from the inside thereof and by the first cold roller, the thermoplastic sheet 1 is placed into press-contact with the outer peripheral surface of the steel pipe 2 from the outside thereof and keeping the condition, while blowing hot air on the peripheral surface of the thermoplastic sheet 1, the steel pipe 2, loading roller 3, and the first cold roller 4 are rotated, thereby to soften and smooth the outer peripheral surface of the thermoplastic sheet 1 while forwarding it in the circumferential direction.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] This invention relates to an intermediate transfer endless belt for transferring a toner image formed on a photoreceptor to its own outer surface and retransferring it to copy paper in an electrophotographic copying machine or the like. The present invention relates to a manufacturing method and an apparatus used therein.

0002

[Prior Art] A full-color toner image formed on a photoreceptor is first transferred onto the outer peripheral surface of an intermediate transfer endless belt made of thermoplastic resin, and then transferred again to copy paper. A modern full-color electrophotographic copying machine is normally configured as shown in FIG. That is,
This electrophotographic copying machine includes an optical device 12 that guides light reflected from an original 11, a filter 13 that separates the reflected light from the original into three primary colors of red, green, and blue, and a belt-shaped photoreceptor 14 having photoconductivity. , a developing device 15, an intermediate transfer endless belt 17 that once transfers the toner image formed on the photoreceptor 14 onto its own outer peripheral surface before copying it onto copy paper 16, and a fixing device 1.
It is equipped with 8. More specifically, a charger 19 is provided near the starting end of the photoconductive belt-shaped photoreceptor 14, and three developing sections 15a to 15c are provided in the middle of the photoreceptor 14. It is being The belt-shaped photoreceptor 14 is charged by the charger 19 and then exposed to light reflected from the original projected from the optical device 12, so that an electrostatic latent image is formed thereon. In this case, as described above, the projection path of the optical device 12 that projects the reflected light of the original onto the photoreceptor 14 is arranged such that the reflected light of the original is red,
A filter 13 is provided that separates the light into the three primary colors of green and blue, and the separated primary color light is guided onto a belt-shaped photoreceptor 14 in order, for example, red first, then green, and so on, where each of the electrostatic charges Form a latent image. The developing device 15 includes three developing sections 15a,
15b and 15c, each containing toner of three colors corresponding to the separated three primary colors. The latent image formed by the color-separated light is
It is colored and developed with toner corresponding to that color. That is,
A colored toner image is formed for each color by the above three types of toner, and this is caused by the action of the primary transfer roller 20.
The toner images are sequentially transferred onto the outer surface of the endless intermediate transfer belt 17 to form a full-color toner image on the endless intermediate transfer belt 17 . In this way, the copying machine sequentially transfers the colored toner images formed for each color onto the copy paper 16, and instead of forming the colored toner images on the copy paper 16, the copying machine expands and contracts due to humidity, etc. A colored toner image is once formed on the endless intermediate transfer belt 17. Then, the toner image is retransferred onto the copy paper 16 supplied from the paper cassette 21 by the action of the secondary transfer roller 22. The retransferred full-color toner image is sent to the fixing device 18 as the copy paper 16 is conveyed and is fixed thereon, and the copy paper 16 with the toner image fixed thereon is transferred to the fixing device 18 and fixed thereon.
is sent out from the copying machine as shown by the arrow. 23 is a conveyor belt.

As described above, in the electrophotographic copying machine described above, toner is once transferred from the photoreceptor 14 to the intermediate transfer endless belt 17, and then the toner is transferred from the intermediate transfer endless belt 17 to the copy paper 16.
will be retranscribed. Therefore, in addition to the electrical resistivity of the semiconductor region (108 to 109 Ωcm), the intermediate transfer endless belt 17 is free from local irregularities, circumferential and axial lines, and wrinkles from the viewpoint of surface condition. , preferably the surface is a mirror surface, and from the viewpoint of circumferential precision, the circumferential length should have an accuracy of ±0.5 mm, for example, in the case of a diameter of 200 mm, so that the belt does not loosen when attached to the machine. , and from the viewpoint of thickness accuracy, in order to prevent local unevenness of contact with the photoconductor 14 and copy paper 16 during installation on the machine, for example, in the case of a thickness of 200 μm, the thickness should be ±±.
It is required to have an accuracy of 20 μm. However, when the intermediate transfer endless belt 17 is manufactured by blow molding, the surface condition in the axial direction is poor due to mold parting, and when manufactured by inflation molding, the accuracy of the circumferential length is poor. For this reason, the intermediate transfer endless belt 17 is manufactured by an extrusion molding method, particularly by an inside mandrel method which can obtain good circumferential length accuracy.

0004

[Problem to be solved by the invention] However, the thickness 5
When manufacturing a particularly thin intermediate transfer endless belt 17 with a thickness of 0 to 500 μm by extrusion molding, even if the above-mentioned inside mandrel method is used, uneven linear velocity of the extruded resin, uneven flow inside the extrusion mold, etc. The actual situation is that even slight fluctuations in the uneven take-up speed cause non-uniform circumferential length and thickness, making it impossible to obtain an endless intermediate transfer belt 17 that satisfies the above requirements. Furthermore, the extrusion molding method has a problem in that streaks such as die scars occur in the extrusion direction.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a method for manufacturing an intermediate transfer endless belt with good surface condition, circumferential length accuracy, and thickness accuracy, and an apparatus used therefor.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a load roller inserted into a cylindrical body, and a thermoplastic sheet formed into an endless belt outside the cylindrical body.
A guide roller is disposed so that its inner circumferential surface faces the outer circumferential surface of the cylindrical body, and a guide roller whose outer circumferential surface is mirror-finished is disposed outside the thermoplastic sheet. The body is pressed against the inner peripheral surface of the thermoplastic sheet from the inside, and the thermoplastic sheet is pressed against the outer peripheral surface of the cylindrical body from the outside by the guide roller, and in this state hot air is applied to the peripheral surface of the thermoplastic sheet. The first gist is a method for manufacturing an intermediate transfer endless belt, in which the cylindrical body, the load roller, and the guide roller are rotated while spraying the thermoplastic sheet, and the outer circumferential surface of the thermoplastic sheet is softened and smoothed while being fed in the circumferential direction. A loaded roller is inserted into a thermoplastic sheet formed into an endless belt shape, a guide roller whose outer peripheral surface is mirror-finished is arranged outside the thermoplastic sheet, and the thermoplastic sheet is rolled by the loaded roller. The thermoplastic sheet is pressed against the outer circumferential surface of the guide roller from the inside, and in this state, the load roller and the guide roller are rotated while blowing hot air onto the circumferential surface of the thermoplastic sheet, and the thermoplastic sheet is conveyed in the circumferential direction while the outer circumferential surface of the thermoplastic sheet is rotated. The second gist is a method for manufacturing an intermediate transfer endless belt in which the surface is softened and smoothed. a thermoplastic sheet disposed outside the cylindrical body; a load roller inserted into the cylindrical body to press the cylindrical body from the inside against the inner circumferential surface of the thermoplastic sheet; and an outer circumferential surface disposed outside the thermoplastic sheet. a guide roller that presses the thermoplastic sheet, which has been mirror-finished, against the outer circumferential surface of the cylindrical body from the outside; a hot air blowing means that blows hot air onto the circumferential surface of the thermoplastic sheet; the cylindrical body, the load roller, and the guide roller. The third gist is an apparatus for manufacturing an intermediate transfer endless belt, which includes a rotating means for rotating the intermediate transfer endless belt, and a guide roller disposed outside the thermoplastic sheet formed into the endless belt shape and having a mirror-finished outer peripheral surface; A load roller that is inserted into a plastic sheet and presses the thermoplastic sheet from the inside against the outer circumferential surface of the guide roller, a hot air blowing means that blows hot air onto the circumferential surface of the thermoplastic sheet, and the load roller and the guide roller. The fourth aspect is an apparatus for manufacturing an intermediate transfer endless belt, which includes a rotating means for rotating the intermediate transfer endless belt.

[0007]

[Operation] That is, in the present invention, a load roller is inserted into a cylindrical body, and a thermoplastic sheet formed in the shape of an endless belt is placed outside the cylindrical body so that its inner circumferential surface faces the outer circumferential surface of the cylindrical body. a guide roller having a mirror-finished outer circumferential surface is disposed outside the thermoplastic sheet, and the cylindrical body is pressed against the inner circumferential surface of the thermoplastic sheet from the inside by the load roller; The thermoplastic sheet is pressed against the outer circumferential surface of the cylindrical body from the outside by the guide roller, and in this state, the cylindrical body, the load roller, and the guide roller are rotated while blowing hot air onto the circumferential surface of the thermoplastic sheet. As the thermoplastic sheet is fed in the circumferential direction, the outer circumferential surface thereof is softened and smoothed. In addition, a load roller is inserted into a thermoplastic sheet formed into an endless belt shape, and a guide roller whose outer peripheral surface is mirror-finished is provided outside the thermoplastic sheet, and the load roller moves the thermoplastic sheet is pressed against the outer circumferential surface of the guide roller from the inside, and in this state, the load roller and guide roller are rotated while blowing hot air onto the circumferential surface of the thermoplastic sheet to feed the thermoplastic sheet in the circumferential direction. The outer peripheral surface is softened and smoothed. Therefore,
After forming a thermoplastic sheet into a cylindrical shape using extrusion molding and processing it into an endless belt, the surface of the thermoplastic sheet can be smoothed, resulting in excellent surface condition, circumferential length accuracy, and thickness accuracy. An endless intermediate transfer belt can now be obtained, and by using this endless intermediate transfer belt, an excellent effect can be obtained in that images without toner filming or the like can be obtained. Moreover, since hot air is blown to heat the thermoplastic sheet, there is an excellent effect that the molten thermoplastic resin does not adhere to the guide roller.

Next, the present invention will be explained in detail based on examples.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a sectional view of an endless belt surface straightening device showing one embodiment of the present invention, and FIG. 2 is a perspective view thereof. 1 is a sheet-like thermoplastic resin extruded into an endless belt shape using an extrusion molding machine (not shown), and examples of the thermoplastic resin used include polycarbonate (PC) and polypropylene (PP). 2 is a steel pipe, and the thermoplastic resin sheet 1 is coaxially disposed outside the steel pipe 2. The circumference of this thermoplastic resin sheet 1 is 100 to 103% of the circumference of the steel pipe 2, preferably 100 to 1%.
It is set to 01%. 3 is a load roller, the weight of which is set to 100 to 1000 g/cm. This load roller 3 is disposed in the axial direction within the steel pipe 2, and can be raised and lowered within the steel pipe 2 by a lifting device (not shown). That is, when not in use, the load roller 3 is moved upward, and when in use, it is moved downward. Reference numeral 4 denotes a first cold roller (guide roller), and the first cold roller 4 has a polished outer circumferential surface, a mirror-finished surface coated with silicone, and a molten thermoplastic resin on the surface. Prevents resin from adhering. Further, the first cold roller 4 is used as a driving roller that contacts the lower right side portion of the steel pipe 2 via the thermoplastic resin sheet 1 and rotates the steel pipe 2 in a clockwise direction. Reference numeral 5 denotes a second cold roller, which contacts the lower left side portion of the steel pipe 2 via the thermoplastic resin sheet 1, and is used as a driving roller to rotate the steel pipe 2 in a clockwise direction. In this example, the linear speed is set to 0.5 m/min. Reference numeral 6 denotes a hot air blowing nozzle body, which is disposed on the upper right side of the first cold roller 4, and is arranged on the outer circumferential surface of the thermoplastic resin sheet 1 before being pressed against the first cold roller 4 and the steel pipe 2. (arrow A indicates the direction of hot air blowing). The temperature of this hot air is 15 in PP
It is set to 0 to 180°C, and 160 to 190°C for PC.

In the above structure, first, a load roller 3 is disposed inside the steel pipe 2, and a thermoplastic sheet 1 shaped like an endless belt is disposed outside the steel pipe 2. Next, the load roller 3 is moved downward, and the load roller 3 presses the steel pipe 2 against the inner circumferential surface of the thermoplastic sheet 1 from the inside, and the first cold roller 4 presses the steel pipe 2 against the inner peripheral surface of the thermoplastic sheet 1. The sheet 1 is pressed against the outer peripheral surface of the steel pipe 2 from the outside. In this state, the first cold roller 4 and the second cold roller 5 are rotated while blowing hot air from the hot air blowing nozzle body 6 toward the outer circumferential surface of the thermoplastic resin sheet 1. Rotate the load roller 3 clockwise. As a result, the thermoplastic sheet 1 moves along the outer circumferential surface of the steel pipe 2, and the circumferential surface of the thermoplastic sheet 1, which has been heated and softened by the hot air, is transferred to the mirror-finished first cold roller 4. smoothed on the outer circumferential surface.

The intermediate transfer endless belt thus obtained has a smooth surface, and has good surface condition, circumferential length accuracy, and thickness accuracy. Furthermore, the molten thermoplastic does not adhere to the first cold roller 4.

FIG. 3 is an explanatory diagram of an endless belt surface straightening device showing another embodiment of the present invention. In this endless belt surface straightening device, the steel pipe 2 is not used, and the thermoplastic resin sheet 1 is pressed against the load roller 3, the first cold roller 4, and the second cold roller 5. Moreover, a hot air blowing nozzle body 6 is provided between both cold rollers 4 and 5, and hot air is applied from this hot air blowing nozzle body 6 to the outer circumferential surface of the thermoplastic resin sheet 1 passing between the cold rollers 4 and 5. The outer circumferential surface of the second cold roller 5 is mirror-finished by spraying, and the surface of the thermoplastic resin sheet 1 is corrected by the second cold roller 5. The other parts are the same in structure as the above embodiment, and have the same effects.

In the above embodiment, the steel pipe 2 is used, but a mandrel may be used instead. Also,
In the above embodiment, the thermoplastic resin sheet 1 is disposed along the steel pipe 2, but the thermoplastic resin may be extruded and coated onto a mandrel.

Further, in the above embodiment, the first cold roller 4 and the second cold roller 5 are used as the driving rollers for the steel pipe 2, but the invention is not limited to this. Only one of them may be used as a driving roller, or means other than the cold rollers 4 and 5 may be used to rotate the steel pipe 2.

Further, in the above embodiment, the outer circumferential surface of the first cold roller 4 is coated with silicone after being mirror-finished, but the invention is not limited to this. It may also be coated with a heat-shrinkable Teflon resin.

[0016]

As described above, in the present invention, a load roller is inserted into a cylindrical body, and a thermoplastic sheet formed in the shape of an endless belt is placed outside the cylindrical body so that its inner peripheral surface is that of the cylindrical body. A guide roller is disposed so as to face the outer circumferential surface, and the outer circumferential surface is mirror-finished outside the thermoplastic sheet.
The load roller presses the cylindrical body against the inner circumferential surface of the thermoplastic sheet from the inside, and the guide roller presses the thermoplastic sheet against the outer circumferential surface of the cylindrical body from the outside. The cylindrical body, the load roller, and the guide roller are rotated while blowing hot air onto the circumferential surface of the thermoplastic sheet, thereby softening and smoothing the outer circumferential surface while feeding the thermoplastic sheet in the circumferential direction. In addition, a load roller is inserted into a thermoplastic sheet formed into an endless belt shape, and a guide roller whose outer peripheral surface is mirror-finished is provided outside the thermoplastic sheet, and the load roller moves the thermoplastic sheet is pressed against the outer circumferential surface of the guide roller from the inside, and in this state, the load roller and guide roller are rotated while blowing hot air onto the circumferential surface of the thermoplastic sheet to feed the thermoplastic sheet in the circumferential direction. The outer peripheral surface is softened and smoothed. Therefore, after forming a thermoplastic sheet into a cylindrical shape using an extrusion method or the like and processing it into an endless belt, the surface of the thermoplastic sheet can be smoothed, and the surface condition, circumferential precision, and thickness can be improved. An intermediate transfer endless belt with excellent accuracy can now be obtained, and by using this intermediate transfer endless belt, an excellent effect can be obtained in that images without toner filming or the like can be obtained. Moreover, since hot air is blown to heat the thermoplastic sheet, there is an excellent effect that the molten thermoplastic resin does not adhere to the guide roller.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an endless belt surface straightening device showing one embodiment of the present invention.

FIG. 2 is a perspective view thereof.

FIG. 3 is a sectional view of an endless belt surface straightening device showing another embodiment of the present invention.

FIG. 4 is a configuration diagram of a full-color copying machine incorporating an endless intermediate transfer belt.

[Explanation of symbols]

1 Thermoplastic sheet 2 Steel pipe 3 Load roller 4 First cold roller 6 Hot air blowing nozzle body

Claims (4)

[Claims] [Claim 1] A load roller is inserted into a cylindrical body, and a thermoplastic sheet formed into an endless belt shape is disposed outside the cylindrical body so that its inner circumferential surface faces the outer circumferential surface of the cylindrical body. A guide roller having a mirror-finished outer circumferential surface is disposed outside the thermoplastic sheet, and the cylindrical body is pressed against the inner circumferential surface of the thermoplastic sheet from the inside by the load roller, and the guide roller is Therefore, the thermoplastic sheet is pressed against the outer circumferential surface of the cylindrical body from the outside, and in this state, the cylindrical body, the load roller, and the guide roller are rotated while blowing hot air onto the circumferential surface of the thermoplastic sheet. A method for producing an endless intermediate transfer belt, which comprises softening and smoothing the outer circumferential surface of a plastic sheet while feeding the plastic sheet in the circumferential direction. 2. A loaded roller is inserted into a thermoplastic sheet formed into an endless belt, and a guide roller whose outer circumferential surface is mirror-finished is provided outside the thermoplastic sheet, and the loaded roller moves the The thermoplastic sheet is pressed against the outer circumferential surface of the guide roller from the inside, and in this state, the load roller and the guide roller are rotated while blowing hot air onto the circumferential surface of the thermoplastic sheet, thereby moving the thermoplastic sheet in the circumferential direction. A method for manufacturing an endless intermediate transfer belt, characterized by softening and smoothing the outer circumferential surface of the belt while being fed. 3. A cylindrical body, a thermoplastic sheet formed into an endless belt shape and disposed outside the cylindrical body so that its inner peripheral surface faces the outer peripheral surface of the cylindrical body, and a thermoplastic sheet inside the cylindrical body. a load roller that is inserted and presses the cylindrical body from the inside against the inner circumferential surface of the thermoplastic sheet; and a load roller that is disposed outside the thermoplastic sheet and whose outer circumferential surface is mirror-finished and presses the thermoplastic sheet from the outside to the outer circumferential surface of the cylindrical body. An endless intermediate transfer system comprising: a guide roller that presses against the thermoplastic sheet; a hot air blowing means that blows hot air onto the circumferential surface of the thermoplastic sheet; and a rotating means that rotates the cylindrical body, the load roller, and the guide roller. Belt manufacturing equipment. 4. A guide roller disposed outside a thermoplastic sheet formed into an endless belt shape and having a mirror-finished outer peripheral surface; An intermediate transfer endless belt comprising: a load roller that presses against the outer circumferential surface; hot air blowing means that blows hot air onto the circumferential surface of the thermoplastic sheet; and rotation means that rotates the load roller and the guide roller. manufacturing equipment.