JPH1016057A - Method for manufacturing endless belt, endless belt obtained thereby transfer material support member using the belt, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a joint with sufficient melt bonding strength of a film, high joining precision, and good flatness by sticking a pressure sensitive adhesive tape to a overlapping part of both ends of a film and giving ultrasonic vibration in joining an endless belt. SOLUTION: In an ultrasonic melt bonding apparatus, with the end parts of a film 21 overlapped, a pressure sensitive adhesive tape 25 is stuck on the overlapping part, and the part is fixed by a clip 24 in this state. Next, at the position of a slit-shaped opening part 26 of the clip 24, the film 21 is held between the tip part of an ultrasonic horn 22 and a jig 22, the horn 22 is moved while being pressed, and ultrasonic vibration is given to it. Then, the film 21 is melt-bonded through the tape 25 by ultrasonic energy, and a transfer material support member in which a step and the shape of a projected part is corrected finally and which has high adhesive strength and high flatness is obtained. The preferable thickness of the film is 30-500μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an endless belt by bonding both ends of a film to each other by an ultrasonic fusion method, an endless belt obtained by the method, and an electrophotograph having the endless belt. The present invention relates to a transfer material carrying member of an image forming apparatus such as a copying machine and a printer of a system.

[0002]

2. Description of the Related Art Generally, thermoplastic resin films can be easily joined by softening by applying heat energy from the outside in a state where a considerable number of thermoplastic resin films are in contact with each other and pressed. Can be. However,
Even if the same thermoplastic resin film is used as a polyethylene terephthalate film, it cannot be satisfactorily joined by the above-mentioned method in the case of a film having no heat welding property in a softened state. Therefore, a joining method is performed in which ultrasonic vibration is applied while a pressing force is applied to the joining portion to locally melt and integrate the contact surface.

[0003] Such a general device for joining using ultrasonic vibration is an ultrasonic transmitter, a horn fixed thereto, a base stand arranged at a position facing the horn, and a horn. , And a mechanism for applying a pressing force to the horn so that the film is pressed between the horn and the base.

Therefore, even in the case of a thermoplastic resin film having no heat-sealing property (heat-sealing property), the joint portion is sandwiched between the ultrasonic horn and the base table, and is subjected to ultrasonic vibration while receiving a pressing force. , They are easily welded (see FIG. 2). In this case, specifically, the thermoplastic resin film is sandwiched between the ultrasonic horn 13 and the base 14 with both ends thereof overlapped, and is ultrasonically fused under pressure.

[0005] In this method, both end portions of the film appear to be firmly joined to each other, but in reality, only the contact surfaces thereof are welded to each other. When force is applied, there is a problem that the film easily peels off. Besides, by superposition,
The joining portion becomes thick, and the flatness of the joined film is poor. Furthermore, during ultrasonic welding,
In the process in which the horn fixed to the ultrasonic transmitter scans the superposed sheets, the superimposed film portion may be displaced within a very small range, causing distortion in the ultrasonic welding portion. There is.

As shown in FIG. 2, the method of manufacturing an endless belt by bonding both ends of a film is not satisfactory in terms of welding strength and bonding accuracy, and the film bonding portion is not flat. It has the disadvantage that it does not. In particular, when such a film is used for a transfer material carrying member used in an image forming apparatus, the defect of the joint of the film becomes a fatal problem.

That is, as one type of a color image forming apparatus of the color separation image superimposing transfer system, a plurality of photosensitive members are
When forming different toner images, respectively, the toner images on each photoconductor are transferred by contacting the photoconductor sequentially, aligning the position with respect to a single transfer material being conveyed, and forming a full-color image. There's something I got.

One example of a color image forming apparatus of this type is as follows.
FIG. 1 shows a schematic configuration of the image forming apparatus. Here, the image forming apparatus has photosensitive drums 1a to 1d, around which primary band electricity 2a to 2d, exposing means 3a to 3d, and developing means. Devices 4a to 4d, transfer chargers 5a to 5d, discharger 6a
6d and 7a to 7d, and a photosensitive drum cleaning device 8a to 8d, respectively, and an endless belt-shaped transfer material carrying member 11 is arranged below the photosensitive drum so as to penetrate these units. In addition, a cleaning device 10 for a transfer material carrying member having a urethane blade 9 is disposed.

After the transfer material P 'is fed by the feed roller, the transfer material is conveyed by the transfer material carrying member 11 through the transfer section where the transfer dischargers 5a to 5d are arranged. In general, the support member 11 is formed by overlapping both ends 12 of a sheet-shaped dielectric film and joining them by ultrasonic fusion to form an endless belt. Since a film having a thickness of about 30 to 500 μm is used as the dielectric film used for the transfer material holding member 11, as shown in FIG. Step and a protruding portion occur.

Therefore, if the cleaning device 10 cleans the step, the step cannot be sufficiently cleaned and the toner remains. , And clear streak-like back stains occur. In addition, a step at the joining portion of the transfer material carrying member 11,
The protruding portion is damaged by contact with the cleaning blade 9 (see FIG. 3) or riding on the drive roller (see FIG. 4) during long-term use, and peeling occurs near the joint. There was a problem that would occur. Furthermore, since the joint has distortion and is not flat, the flatness as a belt is poor, and there is a defect that transfer unevenness occurs when a toner image is transferred onto a transfer material.

The present invention has been made on the basis of the above circumstances, and an object thereof is to provide an endless end which can provide a film having sufficient welding strength and bonding accuracy and good flatness. An object of the present invention is to provide a method for manufacturing a belt.

Another object of the present invention is to provide a seamless transfer endless belt having such characteristics, and a transfer material carrying member having the same, such as an image forming apparatus.

[0013]

Means for Solving the Problems In order to achieve the above object, as a result of intensive studies, the present inventor has found that, by overlapping both ends of a film, a horn fixed to an ultrasonic transmitter and a base stand are provided. Ultrasonic fusion is performed by sandwiching the film and applying ultrasonic vibrations.At this time, the adhesive tape is stuck on the laminated film to form the step at the joint of the film and the shape of the protruding part It has been found that an endless belt having a sufficient bonding strength and joining accuracy, and having a joining portion with good flatness can be obtained.

That is, the method of manufacturing an endless belt according to the present invention is a method of manufacturing an endless belt in which both ends of a film are joined to each other by an ultrasonic welding method. It is characterized in that an adhesive tape is stuck on the superposed portion of and the ultrasonic vibration is applied.

In this case, the softening point of the base material of the pressure-sensitive adhesive tape is preferably higher than that of the film base material constituting the endless belt.

[0016]

FIG. 5 is a view showing a state of joining of an endless belt-shaped transfer material image holding member of an image forming apparatus by ultrasonic fusing according to the present invention. 5A and 5B, an apparatus for ultrasonically welding the film 21 includes an ultrasonic horn 22 fixed to an ultrasonic transmitter (not shown) and a jig 23 for mounting the film.
And a clip 24 for fixing the film 21 on the jig 23, and an adhesive tape 25 provided on the film overlapping portion.

The clip 24 has a slit-shaped opening 26.
, And the film 21 is held between the ultrasonic horn 22 and the jig 23 while being fixed with the adhesive tape 25.

In such an ultrasonic welding device 27,
With the ends of the film overlapped, an adhesive tape 25 was stuck on the overlapped portion, and in that state,
It is fixed by the clip 24. Next, of the clip 24,
At the position of the slit opening 26, the adhesive tape 25
Is sandwiched between the tip of the ultrasonic horn 22 and the jig 23. When ultrasonic vibration is applied while pressing in this state, the film 21 is melted by the ultrasonic energy via the adhesive tape 25, and furthermore, the step and the shape of the protruding portion are finally corrected. An endless transfer material carrying member having high strength and high flatness can be obtained. The pressing force and ultrasonic energy required for welding can be appropriately determined in consideration of the material, thickness, welding speed, and the like of the film.

In this embodiment, as shown in FIG. 5B, the jig 23 is fixed and the ultrasonic horn 22 moves. In another embodiment, on the contrary, the ultrasonic horn 22 moves. The horn 22 may be fixed and the jig 23 may move. Further, in the above-described embodiment, the ultrasonic horn 22 has a pencil-shaped tip with a tapered tip, but has a long horn shape in the film width direction and a wide horn shape that covers the entire width of the film. It doesn't matter.

Examples of the film substrate used for the endless belt obtained by the method of the present invention include polyester, polyimide, polyamideimide, polyetherimide, polyethylene, polypropylene, polyurethane, polycarbonate, polystyrene, polyamide, polyvinyl chloride, cellophane. , Acetate and Teflon are preferred.

The film base material of the endless belt includes a filler such as an inorganic feeler and carbon black, and a heat stabilizer and a light stabilizer for the purpose of improving physical properties and chemical properties. A stabilizer, a flame retardant, a plasticizer, an antistatic agent, and the like can be appropriately added.

Further, the thickness of the film to which the present invention is preferably applied is about 1 to 1000 μm.
A film of about 0 to 500 μm is preferred. There is no limitation on the film width (corresponding to the length of the joint).
Also, there is no limitation on the diameter of the endless belt, and 5c
It can be manufactured in a wide range, from less than m to several m or more.

FIG. 6 shows an adhesive tape 2 used in the present invention.
It is sectional drawing which shows the structure of No. 5. Here, an undercoat layer 29 and an adhesive layer 30 are applied in this order to the lower layer of the base material 28, and the undercoat layer 29 is used to increase the adhesiveness between the base material and the adhesive layer, or a tape. It is a layer for coloring
This does not have to be. Further, an additive for coloring may be added to the adhesive layer.

As the base material 28 of the adhesive tape, polyester, polyimide, polyamideimide, polyetherimide, polyethylene, polypropylene, polyurethane,
Examples include polycarbonate, polystyrene, polyamide, polyvinyl chloride, cellophane, acetate, and Teflon.

The softening point of the substrate 28 is higher than the softening point of the film substrate of the endless belt. Thus, even when ultrasonic welding is performed in the configuration of the present invention, only the base material of the pressure-sensitive adhesive tape is melted, and welding can be performed, so that the pressure-sensitive adhesive tape and the film base material are not welded. Also, no deformation of the base material of the adhesive tape occurs. Therefore, the adhesive tape can be peeled off after the ultrasonic welding. When the endless belt is used and the adhesive tape is left as it is, it is used as a reinforcing material for the welded portion.

The thickness of the base material of the pressure-sensitive adhesive tape and the thickness of the pressure-sensitive adhesive layer are determined according to the material and thickness of the film base material of the endless belt to be subjected to ultrasonic welding.
It is appropriately selected depending on the degree of the energy applied by the ultrasonic wave, whereby the shape of the ultrasonic welded portion can be corrected.

The thickness of the pressure-sensitive adhesive tape applied in the present invention is 1 to 100 μm, and particularly preferably 3 to 50 μm. The thickness of the pressure-sensitive adhesive layer is preferably 1 to 100 μm, and more preferably 1 to 50 μm.

Further, as described above, the transfer material supporting member used in the image forming apparatus employing the endless belt manufactured by the method of the present invention can be used for the overlapping portion of the film when performing the ultrasonic fusion. Adhesive tape is stuck on the upper part, but this adhesive tape should be used as it is when it is used as a transfer material carrying member of an image forming apparatus after its manufacture, either as it is or in a peeled state. Can be.

Therefore, in the joint portion of the films joined by the ultrasonic welding, the shape of the step and the protruding portion is corrected, the fusion strength of the endless belt is increased, the joining accuracy is increased, and the flatness is improved. And, for example, when applied to a transfer material, a uniform toner image can be obtained without causing belt cleaning failure.

[0030]

【Example】

Embodiment 1 Hereinafter, a preferred embodiment of the present invention will be described in detail. As described above, for example, the transfer material image holding member of the image forming apparatus shown in FIG. 5 is formed in an endless belt shape by ultrasonic fusion. Sa: 100 μm,
A width: 350 mm and a length: 1450 mm are used. As described above, the ultrasonic welding apparatus is used to fix the ultrasonic horn 22 fixed to the ultrasonic transmitter (not shown), the jig 23 for mounting the film, and the film 1 on the jig 23. Is used. A polyethylene naphthalate film (thickness: 12 μm) was used as a base material as the adhesive tape 25 on the film overlapping portion, and Sibinol ATH-500 (manufactured by Siden Chemical Co., Ltd.) was used as the adhesive layer.
m).

As an ultrasonic welding device, a plastic welder (UE200Z28S-9) manufactured by Ultrasonic Industry Co., Ltd. is used.
K) and a configuration as shown in FIGS. 5A and 5B.
Here, the pressing force of the ultrasonic horn 22: 5 kg / cm
^2. Ultrasonic fusion of the film was performed at a scanning speed of 10 mm / sec.

The obtained transfer material image holding member was employed in the color image forming apparatus shown in FIG. 1, and a durability test was performed on 10,000 copies using this image forming apparatus. Table 1 shows the results. [Embodiment 2] A second embodiment of the present invention is as follows. That is, Example 1 was repeated except that a polyimide film (thickness: 12 μm) was used as the base material of the adhesive tape 25.
The same conditions were used. Table 1 shows the results. [Embodiment 3] A third embodiment of the present invention is as follows. That is, the conditions were the same as in Example 1, except that a polyamideimide film (thickness: 12 μm) was used as the base material of the adhesive tape 25. Table 1 shows the results. [Embodiment 4] A fourth embodiment of the present invention is as follows. That is, the same conditions as in Example 2 were used except that polyethylene terephthalate (thickness: 125 μm) was used as the base material of the film 21 and the scanning speed of the ultrasonic horn 22 was 8 mm / sec. Table 1 shows the results.
Shown in Embodiment 5 A fifth embodiment of the present invention is as follows. That is, the conditions were the same as in Example 4, except that a polyamideimide film (thickness: 12 μm) was used as the base material of the adhesive tape 25. Table 1 shows the results. Comparative Example 1 A transfer material carrying member was prepared and evaluated in the same manner as in Example 1 except that no adhesive tape was used during the production of the endless belt. Table 1 shows the results. Comparative Example 2 A transfer material carrying member was prepared and evaluated in the same manner as in Example 4 except that no adhesive tape was used. Table 1 shows the results.

[0033]

[Table 1]

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an example of a color image forming apparatus capable of embodying the present invention.

2A is a conceptual diagram showing a film joining method by ultrasonic welding, and FIG. 2B is a conceptual diagram showing a joining portion joined by a film joining method by ultrasonic welding.

FIG. 3 is a conceptual diagram of a cleaning method of a transfer material supporting member in a transfer material of the image forming apparatus.

FIG. 4 is a conceptual diagram showing a situation when a joining portion joined by a film joining method by ultrasonic welding rides on a driving roller unit.

FIG. 5 is a conceptual diagram illustrating a film bonding method according to the present invention.

FIG. 6 is a cross-sectional view showing a configuration of an adhesive tape used in the present invention.

[Explanation of symbols]

 21 Film 22 Ultrasonic Horn 23 Jig 24 Clip 25 Adhesive Tape

Claims (7)

[Claims] 1. A method of manufacturing an endless belt by bonding both ends of a film to each other by an ultrasonic welding method. In the method of bonding, the bonding of both ends of the film is performed, and an adhesive tape is stuck to the overlapping portion of the film. And a method for producing an endless belt by applying ultrasonic vibration. 2. The softening point temperature of the base material of the pressure-sensitive adhesive tape,
The method for producing an endless belt according to claim 1, wherein the temperature is higher than the softening point temperature of the substrate of the film. 3. The film base material is made of polyester,
Polyimide, polyamide imide, polyether imide,
3. The method for producing an endless belt according to claim 1, wherein the method is polyethylene, polypropylene, polyurethane, polycarbonate, polystyrene, polyamide, polyvinyl chloride, cellophane, acetate, or Teflon. 4. The material of the base material of the adhesive tape is polyester, polyimide, polyamideimide, polyetherimide, polyethylene, polypropylene, polyurethane, polycarbonate, polystyrene, polyamide, polyvinyl chloride, cellophane, acetate, and Teflon. The method for producing an endless belt according to any one of claims 1 to 3, wherein: 5. An endless belt manufactured by the manufacturing method according to claim 1. 6. A transfer material carrying member having an endless belt manufactured by the manufacturing method according to claim 1. Description: 7. An image forming apparatus comprising a transfer material carrying member having an endless belt manufactured by the manufacturing method according to claim 1.