JP2003266459A - Releasing method for seamless tubular film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the releasability of a seamless tubular film and its yield and productivity. <P>SOLUTION: In the releasing method for the seamless tubular film F formed on the inner surface 2 of a cylindrical mold 1, after the formation of a cutting line through irradiation with a laser beam 6 on the seamless tubular film F formed on the inner surface 2 of the cylindrical mold 1, the release of the film F from the inner surface of the cylindrical mold is carried out under the condition that the formed position of the cutting line acts as a release starting end. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic copying machine,
A method for releasing a seamless tubular film used in a manufacturing process of a seamless type endless belt used as a belt for intermediate transfer or a belt for fixing in a printer, a facsimile machine, a complex machine of these, etc. Relates to a method of peeling and removing a seamless cylindrical film formed on the inner surface of a cylindrical mold by rotating the cylindrical mold, which has been supplied and developed on the inner surface, while heating to form a dry film.

[0002]

2. Description of the Related Art In recent years, transfer conveyance belts, intermediate transfer belts, transfer fixing belts used in electrophotographic copying machines, etc.
Since functional belts such as photoconductor belts are required to have high speed and high image quality, seamlessness is promoted, and a seamless endless belt made of resin is usually used as a suitable belt.

In this seamless type endless belt, a liquid coating material (for example, a polyamic acid solution) is supplied and developed on the inner surface of a cylindrical mold, and then the cylindrical mold is rotated while being heated to form a dry film. It is manufactured by forming a seamless tubular film on the inner surface of the cylindrical mold, and then peeling the seamless tubular film from the inner surface of the cylindrical mold and taking it out. Further, if necessary, the seamless tubular film after release is subjected to a heat treatment (such as imide conversion with a polyimide belt), and then cut into a predetermined size.

Conventionally, in the above manufacturing process, when the seamless cylindrical film is released from the inner surface of the cylindrical mold,
The edge of the seamless tubular film was lifted up with a cutter such as a cutter, and manually peeled off.

[0005]

However, in the above-mentioned conventional method, the seamless tubular film has a poor releasability and there is a problem in yield and productivity. That is, since the edge of the seamless tubular coating is repeatedly lifted up by a blade, the edge of the coating is scraped off by a blade to form a small piece of the coating, which becomes a defective product by adhering to the completed belt as a foreign matter. A cut is made in the direction of the cylinder axis by a knife at the end, and the film is torn from there, thus lowering the yield. In addition, since the film may tear, mold release work needs to be performed carefully, and the work time becomes long.Because the mold release work is a skilled work, there are individual differences in the work time. The productivity is not good because the work cannot proceed with the fixed tact.

[0006] On the other hand, Japanese Patent Laid-Open No. 2001-18284 discloses a method for manufacturing a seamless belt, in which the formed seamless belt is released from a mold and then conveyed to a cutting stage where unnecessary parts are cut by a laser cutting device or the like. A method of doing so is disclosed. However, this method cannot solve the above-mentioned problems because it is difficult to peel off during release before cutting.

Therefore, the present invention has been made in view of the above circumstances, and an object thereof is to improve the releasability of a seamless tubular film to improve the yield and productivity. It is to provide a method of releasing a film.

[0008]

Means for Solving the Problems In order to achieve the above object, the inventors of the present invention have earnestly studied a method for releasing a seamless tubular film. As a result, the tubular film was irradiated with a laser beam to form a cutting line. It was found that when formed, the adhesive force of the tubular film is weakened by the shrinkage stress generated at that portion, and the film is easily peeled from the mold, and the present invention has been completed.

That is, the method for releasing a seamless tubular coating of the present invention is the method for releasing a seamless tubular coating formed by releasing the seamless tubular coating formed on the inner surface of a cylindrical mold, After forming a cutting line by irradiating the seamless cylindrical film on the inner surface of the cylindrical mold with a laser beam, it is possible to release from the inner surface of the cylindrical mold with the cutting line forming position as the peeling start end. Characterize.

In the above, the cutting line is formed all around along the circumferential direction of the seamless tubular film, and
It is preferable that the cutting lines are formed at positions corresponding to both ends of the product.

The seamless tubular film is formed by supplying a solution containing a polyamic acid as a main component to the inner surface of the cylindrical mold and developing it, and then forming a dry film, or by further heating the film to imidize it. The present invention is particularly effective when it is one.

Further, it is preferable to irradiate the laser light along the circumferential direction by rotating the cylindrical mold while fixing the irradiation source of the laser light.

[Operation and effect] According to the method of releasing the seamless tubular coating of the present invention (hereinafter, abbreviated as "coating releasing method" as appropriate), a cutting line is formed by laser light irradiation. At the position, the film naturally peels off due to the contraction stress, and it becomes easy to locally lift. Therefore, without using a knife,
The operator can easily peel off the seamless tubular film with the cutting line forming position as the peeling start end, and the releasability of the seamless tubular film is improved. As a result, it is possible to improve the yield without the generation of coating film fragments or cuts in the cylinder axis direction as in the case of using a blade, and in addition to being a skilled person, a seamless tubular coating can be used. Since it can be easily peeled off, the work time is shortened, the individual differences in work time are eliminated, and work can be carried out with a fixed tact, and productivity is also improved.

When the cutting line is formed on the entire circumference along the circumferential direction of the seamless tubular film, and when the cutting line is formed at the positions corresponding to both ends of the product, the cutting line is formed on the circumference. Since the film is formed over the entire circumference in the direction, the film is lifted over the entire circumference, so that the seamless tubular film is more easily peeled off. Further, since the cutting lines are formed at the positions corresponding to both ends of the product, the cutting to the desired size can be performed at the same time as the cutting for releasing, and thus the productivity can be further improved.

The seamless tubular film is formed by supplying a solution containing a polyamic acid as a main component to the inner surface of the cylindrical mold and developing it, and then forming a dry film, or by further heating the film to imidize it. In some cases, since the adhesion of the tubular film is large, the mold releasing step is likely to cause a problem particularly in the conventional method. However, the present invention having the above-described effects is particularly effective. Further, in the above film, since the shrinkage stress is large and the film is easily lifted, the seamless tubular film is more easily peeled off.

With the laser light irradiation source fixed,
When irradiating a laser beam along the circumferential direction by rotating the cylindrical mold, the cylindrical mold for forming the tubular film usually has a rotating mechanism, and thus the irradiation of the laser beam is performed. There is an advantage that suitable cutting and releasing can be performed only by installing the source.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a view showing a cylindrical mold for forming a seamless tubular film used in the embodiment, FIGS. 2 and 3 are views showing a laser light irradiation state on a film in the embodiment, and FIG. 4 is a view in the embodiment. It is a figure which shows the cutting line formation condition to a film. In the following, the film releasing method of the embodiment is performed, and finally, an intermediate transfer belt such as an electrophotographic copying machine,
Completed seamless endless belts used for transfer and fixing belts and photoconductor belts.

In the present invention, as shown in FIG. 2, the seamless cylindrical coating F on the inner surface 2 of the cylindrical mold 1 is first irradiated with laser light 6 to form a cutting line L. In the present embodiment, the seamless tubular film F is formed by supplying and developing a solution containing polyamic acid as a main component to the inner surface 2 of the cylindrical mold 1, then forming a dry film, and further heating this to imidize. Here is an example.

The cylindrical mold 1 is made of a metal such as stainless steel (SUS) or aluminum or a heat resistant material such as glass, and has a cylindrical shape having openings 3 and 4 at both ends. A liquid coating material, which is a coating material, is supplied and developed on the inner surface 2 of the cylindrical mold 1 by using a dispenser method or a die method. The liquid coating material can be uniformly spread by traveling at a speed of 20 mm / min by its own weight traveling in a cylindrical mold 1 using a bullet-shaped traveling body (not shown).

Then, the cylindrical metal mold 1 to which the liquid coating material is supplied and developed is rotated while heating with the cylinder axis as a rotation axis to perform solvent removal, imide conversion, dehydration / ring-closing water removal, and then cooling. The liquid coating material supplied and developed on the inner surface 2 of the cylindrical mold 1 is formed into a dry film on the inner surface 2 of the cylindrical mold 1 as a defoamed seamless tubular film having a uniform film thickness. For imide conversion, solvent removal, dehydration / ring-closing water removal, for example, heating is performed at 150 ° C. to 300 ° C. for 30 minutes to 60 minutes.

Subsequently, as shown in FIGS. 2 and 3, the end portion F of the seamless tubular coating F on the inner surface 2 of the cylindrical mold 1 is formed.
By irradiating A with laser light 6 along the circumferential direction of the tubular coating to make a cut, as shown in FIG.
To form. That is, by rotating two sets of rotating rollers 5 and 5 composed of a pair of rollers facing each other in the horizontal direction while being arranged on one side and the other side of the cylindrical mold 1, the rotating rollers 5 and 5 can be rotated.
While rotating the cylindrical die 1 placed on the laser 5, the laser beam 6 output from the laser device 7 which is the irradiation source of the laser beam is applied to the end portion FA on one end side of the seamless tubular film F. To form a cutting line L.

When the cutting line L is formed by the irradiation of the laser beam 6, the film spontaneously peels off due to the contraction stress at the position where the cutting line L of the seamless tubular film F is formed and the film locally floats (or the adhesive force is increased). Weaken). That is, since the automatic release is started at the peeling start end of the seamless tubular film F, the releasability can be improved without using a blade.

Next, the operator quickly peels off the seamless tubular film F with the cutting line L forming position where the film is lifted up as the peeling start end and takes it out to complete the resin seamless type endless belt. Since the releasability of the seamless tubular film F can be improved without using a blade in this way, the yield can be improved without the occurrence of film fragments and cuts in the axial direction of the tube, and the working time is increased. Is short, work time can be eliminated by individual differences and work can be carried out with a fixed tact, and productivity can be improved.

The laser beam 6 used in this embodiment include, but are not limited to a particular laser, for example, CO ₂ lasers, YAG lasers, semiconductor lasers, include excimer laser, especially a CO ₂ laser in the mold It is suitable because it is hard to be scratched.

In the case of this embodiment, the laser beam 6 is rotated in the circumferential direction of the tubular coating F by rotating the cylindrical mold 1 with the tubular axis as the rotation axis while the laser beam 6 is fixed. It is configured to irradiate along. According to this configuration, the cutting line L can be formed by rotating only the cylindrical mold 1, so that the equipment used for the implementation becomes simple. Cylindrical mold 1
The laser light 6 is installed on the equipment for rotating the cylindrical mold 1 when the liquid coating material supplied and developed on the inner surface 2 of the is formed into a dry film.
If it is also used during irradiation, the equipment used for implementation becomes simpler.

Further, in this embodiment, as shown in FIG. 4, the laser device 7 is disposed on the base 7A so as to be movable along the cylinder axis direction of the cylindrical mold 1, and the cutting line L After forming the end face FA on one end side of the seamless tubular film, the laser device 7 is advanced to the other end side in the cylindrical mold 1 as shown by the alternate long and short dash line in FIG. The cutting line L is formed on the other end portion FB of the seamless tubular film F by irradiating the laser beam 6 on the. According to this configuration, since the coating is lifted at the cutting line L forming positions on both one side and the other side of the seamless tubular coating F, the seamless tubular coating F is more easily peeled off.

Further, in the present embodiment, the laser beam 6 is made to make one round along the circumferential direction of the tubular film F without interruption so that both cutting lines L are formed into a complete annular shape.
According to this configuration, since the film is lifted over the entire circumference at the peeling start end of the seamless tubular film F,
The seamless tubular film F becomes easier to peel off.

Further, the specific type of resin in the seamless endless belt made of resin is not limited to a specific type, but polyimide (P
Examples thereof include I) -based resins and polyimide (PI) -based resins mixed with additives such as carbon black which is a conductivity-imparting agent. The raw material of the liquid film is, of course, different depending on the type of resin, and an appropriate amount of polymer, oligomer or monomer suitable for the type of resin and solvent and additives added as needed are blended. Liquid mixture. For example, in the case of a polyimide (PI) resin, a polycarboxylic acid solution obtained by polymerizing tetracarboxylic dianhydride or its moving body and a diamine in an organic solvent in an approximately equimolar amount, or carbon as a conductivity-imparting agent Examples of liquid coating materials include those to which black is added.

[Other Embodiment] (1) In the case of the above embodiment, the seamless cylindrical film F formed on the inner surface 2 of the cylindrical mold 1 was peeled after imide conversion and solvent removal. Alternatively, the seamless tubular film F may be peeled off before the imide conversion / solvent removal etc. and replaced with the outer surface of another metal cylinder, and then the imide conversion / solvent removal etc. may be performed to complete the belt.

(2) In the above embodiment, the film releasing method was applied to the production of seamless type endless belts used for intermediate transfer belts and fixing belts of electrophotographic copying machines and the like. The mold method is not limited to the release of the seamless tubular film for a specific purpose.

(3) In the above embodiment, the cutting line has a complete annular shape. However, the cutting line may have an annular shape with some breaks in the middle.

(4) In the above embodiment, the cutting line is formed on both one side and the other side of the seamless tubular film, but the cutting line is formed on one side and the other side of the seamless tubular film. The structure may be formed in only one of them.

(5) In the above embodiment, an example is shown in which the film is released from the mold manually by an operator, but it is also possible to peel the film off with an automated device. In that case, for example, after suction-fixing the vicinity of the end of the tubular film (preferably the vicinity of both ends) with a suction head, the suction head is moved to the inner peripheral side to partially peel off, and the same operation is performed. By performing the step at another position in the circumferential direction, the product can be released by peeling off the entire circumference.

[0034]

EXAMPLES Examples and the like specifically showing the constitution and effects of the present invention will be described below.

Example 1 First, carbon black dried in 1674 g of N-methyl-2-pyrrolidone (NMP) (manufactured by Cabot Co., Vulcan XC, average primary particle diameter 0.3 μm, specific gravity 1.8 g / cm ³ ). 16.1 g (4% by weight with respect to the polyimide solid content) of a ball mill for 6 hours,
Mix at room temperature. To this NMP dispersion was added 4,4'benzophenone tetracarboxylic dianhydride (BPDA) 294.
2g and para-phenylenediamine (PDA) 108.2g
Was dissolved and reacted at room temperature for 3 hours while stirring in a nitrogen atmosphere to prepare a 3000 poise polyamic acid solution as a liquid coating material.

On the other hand, the cylindrical mold 1 has an inner diameter (openings 3, 4
The diameter of the mold is 330 mm, and the length is 500 mm. First, a polyamic acid solution is applied to the inner surface 2 of the cylindrical mold 1 by a dispenser method so as to have a thickness of 400 μm, and then the cylindrical mold 1 is rotated at 1500 rpm for 10 minutes to even the coating film thickness. The polyamic acid solution was supplied and developed.

Then, while rotating at 250 rpm, hot air of 60 ° C. was applied from the outside of the mold for 30 minutes, and then 150 ° C.
After heating for 60 minutes at 300 ° C. at a rate of 2 ° C./minute and heating for 30 minutes to complete solvent removal, imide conversion, and dehydration / ring-closing water removal, the mixture was cooled to room temperature.

Then, as shown in FIGS. 2 and 3, a cutting line L is formed by using a CO ₂ laser as the laser beam 6 at one end FA of the seamless tubular film F and another end FB of the other end thereof. First, after forming a complete annular shape, the seamless tubular film F is peeled off from the cylindrical mold 1 with the cutting line L forming position as a peeling start end, and taken out to have a thickness of 73 to 78 μm.
We have completed a seamless semi-conductive endless belt made of resin.

In Example 1, the above process was repeated 10 times to produce 10 seamless endless belts.

<Comparative Example 1> An example other than that the seamless cylindrical film F was peeled off and taken out from the cylindrical mold 1 by the conventional method using a cutter knife without irradiating the laser beam 6 was used. A seamless semiconductive endless belt was produced in the same manner as in 1.

Further, regarding the releasing work of the examples and the comparative examples, all 10 belts were checked for the occurrence of film tearing, film breakage, and film fragmentation. The results are shown in Table 1.

[0042]

[Table 1] Comparing the results of Example 1 and Comparative Example 1, it is clear that in the case of Example 1, the yield can be improved by setting the cutting line L forming position formed by the irradiation of the laser beam 6 as the peeling start end. Further, it was well understood that the time required for the mold releasing work in the case of Example 1 was about 50% of that in the case of Comparative Example 1, and the productivity could be improved.

Further, in the case of Example 1, after the seamless type endless belt F was peeled off, it was visually inspected whether the inner surface of the cylindrical mold 1 was scratched by the irradiation of the laser beam 6, but the scratches were found. It was not observed, and it could be confirmed that in the case of the CO ₂ laser, it was possible to avoid scratching the mold.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a cylindrical mold used in an embodiment.

FIG. 2 is a front view showing a laser light irradiation state for forming a cutting line in the embodiment.

FIG. 3 is a side view showing a partially cutaway view of a laser beam irradiation state for forming a cutting line in the embodiment.

FIG. 4 is a cross-sectional view showing a state of forming a cutting line on a film in the embodiment.

[Explanation of symbols]

1 Cylindrical mold 2 Inner surface (of cylindrical mold) 6 laser light 7 Laser device (irradiation source) F Seamless tubular film One end of FA seamless tubular film FB End of the seamless tubular film on the other end side L cutting line

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) // B29K 79:00 B29K 79:00 B29L 23:00 B29L 23:00 (72) Inventor Taiichi Sugita Osaka 1-1-2, Shimohozumi, Ibaraki-shi, Fukuta F-term in Nitto Denko Corporation (reference) 2H033 AA31 BA11 BA12 2H171 FA15 FA19 QC05 QC37 UA03 UA07 WA08 WA11 2H200 FA13 JC04 JC15 JC17 LC09 MA04 MA20 MC08 4F202 AA40 CM08 CA90 CB01 CB01 CA03 CB01 4F205 AA40 AD16 AG01 AG08 AH33 GA02 GB01 GC04 GD02 GN29 GW23 GW34

Claims (4)

[Claims] 1. A method for releasing a seamless tubular coating, which comprises releasing a seamless tubular coating formed on the inner surface of a cylindrical die, wherein a seamless tubular coating on the inner surface of the cylindrical die is provided. A method for releasing a seamless tubular film, which comprises irradiating a laser beam to form a cutting line, and then releasing from the inner surface of the cylindrical mold with the cutting line forming position as a peeling start end. 2. The cutting line is formed around the entire circumference of the seamless tubular film in the circumferential direction, and the cutting line is formed at positions corresponding to both ends of the product. Release method of seamless type tubular film. 3. The seamless tubular coating is formed by supplying a solution containing a polyamic acid as a main component to the inner surface of the cylindrical die and developing it, and then forming a dry coating, or by further heating it for imidization. The method for releasing a seamless tubular film according to claim 1 or 2, wherein 4. The seamless cylindrical film according to claim 2, wherein the cylindrical metal mold is rotated to irradiate the laser light along the circumferential direction while the irradiation source of the laser light is fixed. Mold release method.