JP3532755B2 - Method for producing intermediate transfer member - Google Patents

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 member of a color image forming apparatus for forming a color image on a transfer sheet material such as transfer paper by using toners of a plurality of colors.

[0002]

2. Description of the Related Art As an intermediate transfer member of a first conventional color image forming apparatus, there is, for example, an intermediate transfer member drum for a color image forming apparatus described in JP-A-4-287070. This conventional intermediate image transfer drum for a color image forming apparatus is configured by lining a conductive sponge on the outer peripheral surface of a metal drum, so that the photosensitive drum, the intermediate transfer drum, the transfer roller, and the like can be pressed against each other and vibrated. The eccentricity can be absorbed by the deformation of the conductive sponge of the intermediate transfer drum, the transmission of vibration to other parts can be prevented, and the unevenness of the output print such as jitter can be prevented. It is described as one.

As an intermediate transfer member of the second conventional color image forming apparatus, for example, there is an intermediate transfer member of an electrophotographic apparatus disclosed in Japanese Patent Laid-Open No. 5-150574. This second
The intermediate transfer member of the electrophotographic apparatus according to the conventional example is formed of a seamless loop belt (seamless belt) in terms of electrical characteristics, and is configured to be driven by being stretched over a plurality of rollers. Is.

[0004]

However, in the intermediate transfer drum for the color image forming apparatus according to the first conventional example, the outer surface of the conductive sponge is covered with the conductive rubber. Due to the large roughness, the transferability of the toner image is inferior, and voids and transfer scattering during transfer are likely to occur, and the conductive rubber expands or contracts due to environmental temperature or heat, and toner of each color There is a problem that color misregistration easily occurs between images.

Further, in the electrophotographic apparatus according to the second conventional example, since the intermediate transfer member is a seamless belt that is stretched over a plurality of rollers, the color may change due to the meandering of the belt or the rotational fluctuation of the driving roller. A gap is likely to occur,
If the assembling precision is increased in order to prevent this, the cost of the electrophotographic apparatus becomes significantly high. Further, when slippage occurs due to wear between the belt and the roller, there is a problem in that the rotation fluctuates and color misregistration also occurs, resulting in deterioration of image quality and deterioration of durability.

In view of the above problems, the present invention prevents intermediate defects and color misregistration to form high-quality images, and is inexpensive and excellent in durability, and is an intermediate transfer member of a color image forming apparatus. It is an object of the present invention to provide a method for manufacturing the same.

[0007]

In order to solve the above-mentioned problems, a method of manufacturing an intermediate transfer member according to the present invention comprises a photosensitive member for forming an electrostatic latent image and an electrostatic latent image of the photosensitive member. A developing device that develops to form a toner image, an intermediate transfer member that multiple-transfers toner images of a plurality of colors from the photoconductor, and a transfer device that secondarily transfers the multiple-transferred toner images to a transfer sheet material. In a color image forming apparatus including the above, a cylindrical cylinder base having conductivity, a sponge-like conductive elastic body concentrically laminated outside the cylinder base, and the conductive elastic body A transfer sheet material formed of a non-stretchable resin film concentrically laminated on the outside of the cylinder, and the cylinder base, the conductive elastic body, and a central hole provided at both ends of the transfer sheet material. A method of manufacturing the intermediate transfer member, comprising: a pair of disk members having shafts inserted therethrough, wherein the conductive elastic body is concentrically laminated outside the cylinder base, and the outer peripheral surface of the conductive elastic body is provided. A sheet for elastic body compression is wound around to compress the conductive elastic body in the radial direction, and the cylindrical transfer sheet material is fitted to the outside of the compressed conductive elastic body, and the outer periphery of the conductive elastic body. By sliding the elastic body compression sheet in the axial direction from the surface and pulling it out, the conductive elastic body is radially expanded to bring its outer peripheral surface into contact with the inner peripheral surface of the transfer sheet material, Both ends of the transfer sheet material projecting from both ends in the axial direction of the conductive elastic body are fixed to the circumferential portions of the pair of disc members.

According to the color image forming apparatus manufactured by such a method for manufacturing an intermediate transfer member, since the non-stretchable resin film of the transfer sheet material has a finer surface roughness than rubber, the transfer sheet material is transferred more than rubber. It has excellent properties and is less likely to cause hollow spots or transfer scatter during transfer. Further, since the transfer sheet material does not deform due to temperature or heat unlike rubber, dimensional control is easy and color misregistration is less likely to occur.

Further, in the present invention, the intermediate transfer member is not a seamless belt type one wound around a plurality of rollers but a cylinder type one. Can be prevented,
It is possible to provide an inexpensive color image forming apparatus.

Further, as in the case of a seamless belt type intermediate transfer member which is stretched over a plurality of rollers, slippage occurs between the rollers due to abrasion to cause color misregistration, resulting in deterioration of image quality and durability. Since it does not cause deterioration, it is possible to provide a color image forming apparatus having excellent durability.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. 1 to 1
FIG. 3 is a diagram referred to in order to explain the method of manufacturing the intermediate transfer member of the color image forming apparatus according to the first embodiment of the present invention.

In the color image forming apparatus shown in FIG.
An electrostatic latent image is formed on the photosensitive surface (circumferential surface) of the photoconductor 6 by the laser light R emitted from the laser light unit 9, and the electrostatic latent image is formed by the four developing devices 15-18.
For example, magenta (red), yellow (yellow), cyan (blue)
And developed with black color toner,
The developed color toner images are transferred onto the surface of the intermediate transfer body 1 in multiple.

The intermediate transfer member 1 to which the color toner images are transferred from the photosensitive member 6 onto the circumferential surface is transferred to the transfer roller device 7.
Transfer paper (transfer sheet material) 10 sandwiched between and sent
Then, the multiple color toner images are secondarily transferred. Transfer paper 1 to which the color toner image is secondarily transferred
After passing 0 through the transfer roller device 7, 0 is separated from the intermediate transfer member 1 by removing the charge, and is sent to the fixing device 20 to fix the color toner image.

The cross-sectional structure of the intermediate transfer member 1 as shown in FIG. 2 has, as shown in FIG. 3, a cylindrical cylindrical substrate 2 made of aluminum and having conductivity on the innermost diameter side 1. A sponge-like conductive elastic body 3 having conductivity is provided concentrically on the outer side of the cylinder base body 2. Further, the outer side of the conductive elastic body 3 is seamless and non-stretchable. Transfer sheet materials 4 made of a resin film are concentrically laminated and provided.

The cylinder base 2 may be made of a rigid material such as an iron-based material or a conductive resin, in addition to aluminum. As the material of the transfer sheet material 4, for example, polyetheretherketone (PEEK), polycarbonate, fluororesin or the like can be used. Further, in order to form the transfer sheet material 4 into a seamless shape, that is, a seamless cylindrical shape, it can be formed into such a seamless shape by molding it into a drum shape by an extrusion molding method.

The conductive elastic body 3 is used to elastically deform due to contact with the photosensitive member 6 to secure a nip amount (contact amount) between them, and its volume resistivity is 10 ⁸ Ω.
It is preferable to use those having a size of cm or less. This is because if the volume resistivity is higher than 10 ⁸ Ω · cm, transfer cannot be performed with a transfer voltage that is normally used.

Particularly, the volume resistivity of the conductive elastic body 3 is 10 ⁶
It is preferably in the range of -10 ⁷ Ω · cm, and if it is higher than 10 ⁷ Ω · cm, it is difficult to make the resistance value uniform on the entire surface, and the image is not stable, and if it is lower than 10 ⁶ Ω · cm. The resistance value is different between the surface on which the toner is placed and the surface on which the toner is not placed, and the current is likely to be partially concentrated to deteriorate the transfer sheet material 4.

Further, the hardness of the conductive elastic body 3 is preferably F95 degrees or less, and in the present embodiment, the hardness of the conductive elastic body 3 is F50 degrees. This is because if the hardness of the conductive elastic body 3 is greater than F95 degrees and is too hard, hollowing occurs.

In the present embodiment, the conductive elastic body 3 is formed into a cylindrical shape by adhering both ends of a sheet-shaped one, but it is seamless (from the beginning even if the both ends are not adhered). A cylindrical shape) may be used.

The volume resistivity of the transfer sheet material 4 is 1
The one in the range of 0 ⁸ to 10 ¹³ Ω · cm is used. this is,
If the volume resistivity is less than 10 ⁸ Ω · cm, the surface electric field density of the transfer sheet material 4 increases and reverse transfer (transfer from the intermediate transfer member 1 to the photoconductor 6) increases, which is more than 10 ¹³ Ω · cm. This is because if it is large, the secondary transfer efficiency is lowered and the separability of the transfer paper 10 from the intermediate transfer body 1 is deteriorated. Particularly, the volume resistivity of the transfer sheet material 4 is preferably in the range of 10 ¹⁰ to 10 ¹² Ω · cm.

As shown in FIG. 4, both ends of the transfer sheet material 4 in the axial direction are provided with a cylinder base 2 and a conductive elastic body 3.
Of the disk member 12 having a circumferential surface 12a having a diameter slightly smaller than the inner diameter of the transfer sheet material 4 while being formed to be longer than both end portions of the transfer sheet material 4 in the axial direction. A ring-shaped annular member 14 such as a barb of a barrel is fastened and fixed to the circumferential surface 12a from the outside in the radial direction.

By fixing both ends of the transfer sheet material 4 in the axial direction to the circumferential surface 12a of the disk member 12 in this manner, even if the conductive elastic body 3 is soft, the transfer sheet material 4 is formed.
Can be held in a cylindrical shape while being kept pulled in the outward direction.

FIG. 5 is an exploded perspective view of the intermediate transfer body 1 before both ends of the axial length of the intermediate transfer body 1 are fixed and assembled to the pair of disc members 12 as shown in FIG. . In FIGS. 4 and 5, the shaft 11 is inserted into the center hole of the disk member 12 and constitutes the rotation axis of the intermediate transfer member 1.

According to the color image forming apparatus having such a configuration, since the transfer sheet material 4 has a surface roughness smaller than that of rubber, the transfer property is superior to that of rubber, and hollow defects and transfer scattering occur during transfer. Hard to do. In addition, since the transfer sheet material 4 does not deform due to temperature or heat unlike rubber, dimensional control is easy and color misregistration is less likely to occur.

Further, in this embodiment, since the intermediate transfer member 1 is not a belt-shaped one but a cylinder-shaped one, it is possible to prevent the color misregistration without making the assembly accuracy of the apparatus so high. Therefore, an inexpensive color image forming apparatus can be provided.

Further, like the intermediate transfer member of the seamless belt type according to the second conventional example, slippage occurs due to abrasion between the belt and the roller, and the image quality is deteriorated due to color misregistration and the durability is deteriorated. As a result, the color image forming apparatus having excellent durability can be provided.

Further, the rotation speed can be kept constant by utilizing the inertia of the cylinder substrate 2, and the color shift of the image due to the rotation fluctuation can be minimized. Further, by using the seamless transfer sheet material 4, there is no need for a retracting mechanism or a fixing mechanism for the joints at both ends of the transfer sheet material, which is required when the sheet-shaped transfer sheet material is wound around the conductive elastic body 3. As a result, the color image forming apparatus can be manufactured at low cost.

Further, by adopting the intermediate transfer method using the intermediate transfer body 1, the paper is not limited to a thin paper like the method of directly winding the paper on the drum to form a color image, Similar to the monochrome image forming apparatus in which the paper is not directly wound, the selection range of the thickness of the paper is widened.

The method of manufacturing the intermediate transfer member 1 will be described below. First, as shown in FIG. 7, a sponge sheet-shaped conductive elastic body 3 is wound around the outside of a cylinder base 2 as shown in FIG. 6, and both ends of the conductive elastic body 3 in the circumferential direction are joined together. By bonding the conductive elastic body 3
Is formed in a cylindrical shape.

Next, as shown in FIG. 8, an elastic body compression sheet 5 formed of a release sheet is wound around the outside of the sponge-like conductive elastic body 3 to form the conductive elastic body 3. It is compressed in the radial direction (thickness direction) to reduce the outer diameter and thickness of the conductive elastic body 3.

Next, as shown in FIG. 9, the transfer sheet material 4 is fitted to the outside of the elastic body compression sheet 5 with a gap. After that, as shown in FIG. 10, only the elastic body compression sheet 5 of the release sheet, which was on the outer side of the conductive elastic body 3, is slid and pulled out from the outer peripheral surface of the conductive elastic body 3.

Then, since the elastic body compression sheet 5 that has compressed the conductive elastic body 3 disappears, the conductive elastic body 3 expands in the radial direction (thickness direction) so as to be restored, and FIG.
As shown in FIG. 1, the outer peripheral surface is in contact with the inner peripheral surface of the transfer sheet material 4. At this time, as shown in the figure, both end portions in the axial direction of the transfer sheet material 4 are
And the axial length of the conductive elastic body 3 is set to be longer than both ends.

Next, the circumferential surface 12a of the disk member 12 is fitted to the inner circumferential surfaces of both ends of the transfer sheet material 4 in the axial direction,
Assembly of the intermediate transfer member 1 as shown in FIG. 13 is almost completed. Finally, as shown in FIG. 4, both ends of the transfer sheet material 4 in the axial direction of the disc member 12 are fixed to the disk member 12 by tightening the ring-shaped annular member 14 such as a barrel hook from the outside in the radial direction. By fixing to the circumferential surface 12a and inserting the shaft 11 into the center hole of the disk member 12,
The intermediate transfer member 1 as shown in FIG. 2 is completed.

FIG. 14 is a diagram showing an intermediate transfer member 1 according to a second embodiment of a color image forming apparatus according to the present invention. In the first embodiment described above, both ends in the axial direction of the intermediate transfer member 1 are fixed to the circumferential surface 12a of the disk member 12 by the annular member 14, whereas in the second embodiment. In the first embodiment, both ends of the transfer sheet material 4 of the intermediate transfer body 1 in the axial direction are annularly arranged and embedded in the circumferential surface 12a of the disk member 12, and a foam 22 that gives an expanding force outward in the radial direction is formed. However, it is different in that it is fixed from the inner side in the radial direction by the expansion force.

In the first and second embodiments, both ends of the transfer sheet material 4 of the intermediate transfer member 1 in the axial direction are formed on the circumferential surface 12a of the disk member 12 with the annular member 14 or the foam. It was supposed to be fixed by the body 22, but FIG.
As shown in FIG. 3, both ends of the transfer sheet material 4 in the axial direction may be fixed by screw members 24 such as screws, or both ends of the transfer sheet material 4 may be fixed by using the screw members 24 together with the annular member 14. It may be fixed.

[0036]

As described above, according to the method for manufacturing an intermediate transfer member of the present invention, high quality images can be formed by preventing so-called voids and color misregistration, and at the same time, it is inexpensive and excellent in durability. It is possible to manufacture an intermediate transfer member for a color image forming apparatus.

[Brief description of drawings]

FIG. 1 is a cross-sectional configuration diagram showing a color image forming apparatus having an intermediate transfer member 1 according to a first embodiment of a method for manufacturing an intermediate transfer member of the present invention.

FIG. 2 is a perspective view of an intermediate transfer body 1 in FIG.

3 is a sectional view taken along line III-III of the intermediate transfer body 1 in FIG.

4 is a cross-sectional view of one of both end portions in the axial length of the intermediate transfer body 1 in FIG.

5 is an exploded perspective view of the intermediate transfer body 1 before final assembly. FIG.

FIG. 6 is a perspective view of a cylinder substrate 2 for explaining a method of manufacturing the intermediate transfer body 1.

FIG. 7 is a perspective view of a cylinder substrate 2 and a conductive elastic body 3 for explaining a method of manufacturing the intermediate transfer body 1.

FIG. 8 is a perspective view of a cylinder base 2, a conductive elastic body 3, and an elastic body compression sheet 5 for explaining a method of manufacturing the intermediate transfer body 1.

9 is a perspective view of the transfer sheet material 4 and the elastic body compression sheet 5 for explaining the method for manufacturing the intermediate transfer body 1. FIG.

10 is a perspective view of the transfer sheet material 4 and the elastic body compression sheet 5 for explaining the method for manufacturing the intermediate transfer body 1. FIG.

11 is a perspective view of a cylinder substrate 2, a conductive elastic body 3, and a transfer sheet material 4 for explaining a method of manufacturing the intermediate transfer body 1. FIG.

FIG. 12 is an exploded perspective view of a cylinder substrate 2, a conductive elastic body 3, a transfer sheet material 4, and a disk member 12 for explaining a method of manufacturing the intermediate transfer body 1.

13 is an assembled perspective view of the intermediate transfer body 1 for explaining the method for manufacturing the intermediate transfer body 1. FIG.

FIG. 14 is a cross-sectional view of one of both axial length ends of an intermediate transfer member 1 according to a second embodiment of the method for manufacturing an intermediate transfer member according to the present invention.

FIG. 15 is a cross-sectional view of one of both axial length ends of an intermediate transfer member 1 according to a third embodiment of the method for manufacturing an intermediate transfer member according to the present invention.

[Explanation of symbols]

1 Intermediate transfer body 2 cylinder base 3 Conductive elastic body 4 Transfer sheet material 5 Elastic compression sheet 6 photoconductor 7 Transfer roller device 9 Laser light unit 10 Transfer paper 11 shaft 12 disk members 12a circumferential surface 14 Annular member 15-18 developing device 20 Fixing device 22 foam 24 screw members

Claims (5)

(57) [Claims] 1. A photosensitive member for forming an electrostatic latent image, a developing device for developing the electrostatic latent image of the photosensitive member to form a toner image, and a multi-color toner image from the photosensitive member. A color image forming apparatus comprising: an intermediate transfer member for transferring; and a transfer device for secondarily transferring the multiple-transferred toner images onto a transfer sheet material; A sponge-like conductive elastic body provided concentrically on the outside of the base body, and a transfer sheet formed of a non-stretchable resin film provided concentrically on the outside of the conductive elastic body A method for manufacturing the intermediate transfer member, comprising: a material; and a pair of disk members provided at both ends of the cylinder substrate, the conductive elastic body, and the transfer sheet material and having a shaft inserted through a central hole. The conductive elastic body is concentrically laminated on the outside of the cylinder base, and an elastic body compression sheet is wound around the outer peripheral surface of the conductive elastic body to compress the conductive elastic body in the radial direction, The cylindrical transfer sheet material is fitted to the outside of the compressed conductive elastic body, and the elastic body compression sheet is slid in the axial direction from the outer peripheral surface of the conductive elastic body to pull out the conductive sheet. The elastic elastic body in the radial direction so that the outer peripheral surface of the elastic elastic body contacts the inner peripheral surface of the transfer sheet material, and the shaft of the transfer sheet material protrudes from both ends of the cylinder base and the conductive elastic body in the axial direction. A method for manufacturing an intermediate transfer member, characterized in that both ends in the direction length are fixed to the circumferential portions of the pair of disc members. 2. The method for producing an intermediate transfer member according to claim 1, wherein a release sheet is used as the elastic body compression sheet. 3. The transfer sheet material, wherein both end portions in the axial direction of the transfer sheet material are fixed from the outside in the radial direction by annular members so as to be fixed on the circumferential surface of the disk member. The method for producing an intermediate transfer member according to item 1. 4. The inner side in the radial direction of the transfer sheet material is expanded in the axial direction by the expansion force of a foam body which is annularly arranged on the circumference of the disk member and imparts an expansion force outward in the radial direction. The method for producing an intermediate transfer member according to claim 1, wherein the intermediate transfer member is fixed from the above. 5. The intermediate transfer member according to claim 1, wherein both end portions in the axial direction of the transfer sheet material are fixed on the circumferential surface of the disk member by screw members. Production method.