JPH10333461A - Highly accurate carrying tubular film and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remarkably improve properties such as the strength of a film, internal stress relaxation and impact resistance by interposing one more specific layer between two thermoplastic resin sheet-like films, to obtain a double-layered sheet-like film and using a specific member, to fuse the film and splice both end parts. SOLUTION: One layer is interposed between two thermoplastic resin sheet- like films by using a kind of rubber, elastomer or inorganic thin film having a functional adhesive existing on the surface, to form the double-layered sheet- like film 4. This film 4 is wound on a columnar member 1 and the member 1 is inserted into a tubular member 2, in a state where winding top and bottom ends are overlapped. Then, the whole is maintained in a heated state for a specified time, to fuse the film in the overlapped part and splice both end parts of the film. In a tubular film obtained by this method, the uniformity of film thickness accuracy is ±5 μm and materiality such as an elastic modulus and the impact resistance is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tubular film used for a transport belt used for transporting a precision part at a predetermined position with a high positional accuracy. It is also used as an annular, tubular, tubular, ring-shaped, and belt-shaped film such as a sealed package for storing and storing, but the main application field of the tubular film of the present invention is as a functional part of an image forming apparatus. In the use of.

[0002] Particularly, it is preferably used for a film for carrying a toner carrier or for fixing an image or a belt.

[0003]

2. Description of the Related Art Conventionally, as a method for producing a tubular film, the present applicant has previously proposed a method (Japanese Patent Application No. Hei 6-27761).
As shown in 5), start and end the winding of a thermoplastic resin sheet film or a composite film in which a metal thin film sheet, a glass fiber, a cross sheet, and a carbon thin film sheet are sandwiched between thermoplastic resin sheet films. Wound around a cylindrical member so as to overlap, and fit the tubular mold agent on the outside of the wound film, then heat the whole, and join the overlapping portion of the film or composite film to turn the sheet-like film into a tube. There is a way to do that. At this time, by setting the thermal expansion coefficient of the cylindrical member larger than the thermal expansion coefficient of the tubular mold member, the gap between the two during heating is reduced, and the step (thickness unevenness) of the overlapped portion can be eliminated. The film thickness can be made uniform over the entire circumference, and the thickness of the product can be arbitrarily controlled by adjusting the setting of the gap.

[0004]

Since the main material of the tubular film manufactured by the above-mentioned conventional manufacturing method is a thermoplastic resin, when heated, residual stress inside the film becomes apparent, and the film surface is heated. In many cases, wrinkles occurred. Therefore, it is an object of the present invention to obtain a tubular film having a composite of a thermoplastic film and a rubber or an elastomer and having improved elasticity by relieving internal stress by its elasticity.

[0005] The tubular film produced by the above-mentioned conventional method is a composite film of an inorganic substance and an organic substance. The adhesiveness between the inorganic thin film sheet and the thermoplastic resin film is weak, and the durability of the film itself is low. However, it has a lower property than a tubular film of a thermoplastic resin alone.

Accordingly, the present invention provides a tubular film in which the characteristics of the above-mentioned conventional thermoplastic resin tubular film are further improved, a method of manufacturing the same, and a fixing device, a transport unit and the like using the film. In particular, the present invention proposes a film-like transport member suitable for transporting an information recording member such as a paper material carrying toner for image formation under heating and pressing conditions.

A first object of the present invention is to provide a fixing device for carrying out an image fixing operation or a transfer operation by conveying an image carrier such as paper carrying an image in an image forming apparatus, and a closed loop used for a transfer device. The object of the present invention is to obtain a highly durable material at a low cost by using a tubular film of the above.

[0008] Further, the present invention relates to the first object of the present invention to obtain a tubular film having high uniformity of the film thickness, which is one of the accuracy of the tubular film.

A second object of the present invention is to provide a method for producing a tubular film having the above-mentioned properties while maintaining high productivity.

A third object of the present invention is to obtain the above-mentioned improved tubular film by arbitrarily setting the film thickness to a desired film thickness.

[0011] A fourth object of the present invention is to provide a method of manufacturing the improved tubular film in which the mold is easily released from the tubular mold member and the columnar member, and the productivity is higher. is there.

Further, the present invention provides a fixing device which does not cause a problem such as an offset at the time of fixing toner of an image forming apparatus by using a tubular film which has achieved the above-mentioned object, and provides a high definition image by the fixing device. It is a final task to obtain an obtainable image forming apparatus.

Another object of the present invention is to configure a belt of an image forming apparatus and other transporting means.

[0014]

As a method of obtaining the tubular film of the present invention, a multi-layer structure is provided by interposing another layer as defined in claim 1 between two thermoplastic resin sheet films. A sheet-like film is wound around the cylindrical member 1, and the cylindrical member 1 is inserted into the tubular mold member 2 in a state where the winding start and the winding end are overlapped with each other. A method of welding the film of the joint portion 15 and joining both end portions of the film. Here, it is proposed to use any one of a kind of rubber, a kind of elastomer, or a kind of inorganic thin film having a functional adhesive present on the surface as another layer interposed between the layers.

It is also proposed that one kind of the rubber or one kind of the elastomer is a fine particle such as a rubber particle or an elastomer particle, and a liquid material such as a liquid rubber or a liquid elastomer.

According to these proposals, the tubular film obtained by implementing the present invention has the following excellent properties.

1. Compared with a single thermoplastic resin film, the elastic modulus is improved and the impact resistance is improved.

2. The internal stress in the thermoplastic resin film is reduced by rubber or elastomer.

3. Since the elastic modulus is improved, meandering during use is prevented.

Since the physical properties of the transport film are improved as described above, the tubular film obtained by the present invention is suitably used as a transport belt of an image forming apparatus.

Next, the material of the thermoplastic resin sheet film applicable to the present invention will be described.

As the material of the sheet-like film that can be used in the present invention, any material can be used as long as it is a thermoplastic resin or an elastomer material. In particular, polyethylene, polypropylene, polymethylpentene-1, polystyrene, Vinyl chloride, vinylidene chloride, vinyl acetate resin, cellulose resin, etc., and also polyamide resin, polycarbonate, polyacetal, polysulfone, polyarylate, polyethylene terephthalate, polybutylene terephthalate, polyphenylene oxide, polyphenylene sulfide, polyphenylene sulfide, polyether sulfone , Polyether nitrile, thermoplastic polyimide-based material, polyether ether ketone, liquid crystal polymer, polyamic acid, and the like.

The present invention can also be applied to a film in which organic or inorganic fine powder is blended with the above resin material for the purpose of heat-resistant reinforcement, electrical conductivity and thermal conductivity, or a film stretch-strengthened at various magnifications. Can be used for

Here, as the organic fine powder, for example, a condensation type polyimide powder or the like is used, and as the inorganic fine powder, carbon black powder, magnesium oxide powder, magnesium fluoride powder, silicon oxide powder, aluminum oxide powder,
Inorganic spherical fine particles such as boron nitride powder, aluminum nitride powder, and titanium oxide powder, fibrous particles such as carbon fiber and glass fiber, potassium titanate, silicon carbide, silicon nitride, and other shapes and sizes including whisker-like powder Pulverized fine powder is preferred.

It is preferable that the total amount of these fine powders is 5 to 70 wt% based on the resin material.

An anaerobic adhesive as an example of the functional adhesive referred to in the present invention is a one-part adhesive which cures or solidifies at room temperature when it loses contact with oxygen. For example, those described in catalogs of Three Bond, Loctite, etc.)
You can also see this in 183261.

Further, the elastic adhesive is described in, for example,
With the elasticity also found in 09098, it shows an adhesive action,
Since the adhesion is improved and the impact resistance is improved, the durability is improved.

As for the inorganic adhesive, as a specific example, the product name “ThreeBond 37” is used as a heat-resistant inorganic adhesive.
32 "has specific properties as a heat-resistant inorganic adhesive using a metal alkoxide as a binder, and is mainly used for filling and fixing ceramics, glass, and metal, as a heat-resistant molding material, and as a filler for high-temperature parts. It has been known.

The significance of using an inorganic adhesive in the present invention is explained as follows.

In the case of an organic adhesive, even an imide adhesive having the highest heat resistance is usually used at a temperature of 400 ° C.
The degree is said to be the limit. Even in this case, thermal degradation occurs due to long-term use, and the bond in the polymer is broken, so that the adhesiveness to the base material also decreases.

Therefore, use of an inorganic adhesive which does not cause insufficient heat resistance or thermal deterioration of the organic adhesive is taken up.

The use of a conductive adhesive will be further described. An epoxy resin having excellent adhesive strength is used as a binder.
A conductive adhesive obtained by uniformly mixing and dispersing silver powder as a conductive filler is known as “ThreeBond 3301”. By using such a conductive adhesive, the thermal conductivity is improved. The thermal conductivity of the tubular film obtained by molding the composite film is about 1.3 times higher than that of the tubular film not using the adhesive. When a tubular film using a conductive adhesive is used as a fixing film of an image forming apparatus, the heat conductivity is improved, so that fixing can be performed with about 85% of energy as compared with the related art.

As described above, the use of the conductive adhesive in the present invention utilizes the good thermal conductivity.

As the inorganic thin film sheet, a metal thin film sheet, a glass cloth fiber sheet, a carbon fiber cloth sheet and the like can be used. As a material of the metal thin film sheet, iron, copper, nickel, stainless steel, titanium, SUS
Use is possible.

In order to improve the durability, which is an object of the present invention, it is necessary to apply a functional adhesive to both surfaces of the inorganic thin film sheet by spraying or dipping as another layer sandwiched between thermoplastic sheet films. suggest.

It is also proposed that the functional adhesive be an anaerobic adhesive.

It is also proposed that the functional adhesive be an elastic adhesive.

It is also proposed that the functional adhesive be an inorganic adhesive.

It is also proposed that the functional adhesive be a conductive adhesive.

According to these proposals, the obtained tubular film is made of a thermoplastic sheet-like film with an adhesive, as compared with a tubular film in which an inorganic thin film sheet is integrally formed between thermoplastic sheet-like films according to the prior art without an adhesive. The following effects are obtained because the adhesion between the sheet and the inorganic thin film sheet is improved.

1. Several times higher durability.

2. Several times improvement in thermal conductivity.

3. Several times improvement in film strength.

Regarding wrinkling of the film generated by heating, a composite film in which an inorganic thin film sheet coated with an elastomer or an adhesive on both sides is sandwiched between two thermoplastic resin films is formed into a tubular shape, and the tubular film is formed. By using it as a fixing film for an image forming apparatus,
The following merits are obtained.

1. The elastomer reduces internal stress caused by uneven heating of the heater for heating the fixing film, and can suppress generation of wrinkles on the surface of the fixing film.

2. By sandwiching the inorganic thin film sheet, it is possible to suppress expansion of the thermoplastic resin film due to the above-described heater, thereby suppressing generation of wrinkles on the fixing film surface.

As described above, the performance of the film of the present invention as a high-precision transport film is improved, but the manufacturing cost is improved as follows by adopting the structure of the present invention. That is, if the elastomer component is blended into pellets of the thermoplastic resin and formed into a film to form a tubular film, wrinkles generated at the time of heating the heater can be suppressed, but there is a problem that the cost increases.

Accordingly, the present invention has been proposed as a technique for inexpensively introducing an elastomeric element into a tubular film obtained by the current molding method.

From the above description, it is understood that the tubular film of the present invention has a high precision for conveyance. However, if the description is further supplemented, the present invention in which an elastomeric element is introduced is used. When the tubular film is used as a fixing film for an image forming apparatus, it is possible to suppress wrinkles locally generated on the surface of the fixing film due to heat of a heater, which can also contribute to maintaining high accuracy.

When a tubular film sandwiching an inorganic thin film sheet is used as a fixing film, the entire film has high rigidity, so that rotation unevenness and meandering can be prevented. The fact that the tubular film of the present invention is excellent in impact resistance is as follows.

Conventionally, as a technique for improving the internal stress and impact resistance of a thermoplastic resin, rubber particles are dispersed in the resin, and pellets expressing an elastomeric element are used as a material of the film. Attempts have been made to improve resistance and impact resistance.

However, there is a problem that the above-mentioned method is costly. Therefore, in the present invention, the above-described problem is solved by sandwiching the elastomer between the thermoplastic resin films to avoid an increase in cost.

The improved properties of the tubular film of the present invention have the following effects on the thermal conductivity. Regarding the toner offset, the composite film in which the inorganic thin film sheet is sandwiched between the thermoplastic resins is clearly improved in the thermal conductivity as compared with the film having the same thickness when focusing on the thermal conductivity.

Therefore, when a composite film is used as a fixing film for an image forming apparatus, the offset of toner is reduced due to good thermal conductivity.

Next, obtaining a high-definition image When a tubular film made of a thermoplastic resin is used as a fixing film for an image forming apparatus, if three thick sheets such as envelopes enter the fixing device at the same time, fixing is performed. The temperature rises rapidly, and wrinkles may be formed on the surface of the fixing film, or the film itself may be deformed, which may affect the image.

Therefore, the use of the composite film of the present invention does not cause wrinkles or deformation even in the case of the above-mentioned excessive temperature rise, so that a high-definition image can be obtained.

The fourth aspect of the problem to be solved is to facilitate releasing the tubular film from the member used for heating and to obtain high productivity. The material composition used in the present invention is as follows. Examples of forming a composite film in which an inorganic thin film sheet is sandwiched between sheet-like films into a tubular film are shown (Examples 4 to 7).

In the tubular film using the composite film, in the releasing step, the inorganic thin sheet is interposed between the sheet films, so that the heat shrinkage of the sheet film is suppressed (about 5% → 1%). Therefore, the mold release from the cylindrical member is easier than in the case of the conventional mold release of a tubular film composed only of a sheet-like film.

As described above, since the tubular film obtained by the present invention is suitable for high-precision conveyance, it is proposed to use it as a conveyance belt of an image forming apparatus.

[0060]

1 to 15 illustrate an embodiment of the present invention.

(First Embodiment) In each figure, reference numeral 1 denotes a cylindrical member as a mandrel for winding a multilayer sheet film, and in this example, a solid rod member is used. Numeral 2 denotes a tubular or hollow tubular member having an inner diameter through which the cylindrical member 1 is inserted by winding a film.

In this example, aluminum is used for the columnar member 1 and stainless steel is used for the tubular mold member 2. The coefficient of thermal expansion of aluminum is 2.4 × 10
^-5 (/ ° C), the coefficient of thermal expansion of stainless steel is 1.2 × 10
^-5 (/ ° C).

Next, an embodiment will be specifically described.

The dimensions of the sheet film are selected according to the inner diameter of the tubular film to be manufactured, and the sizes of the cylindrical member 1 and the tubular mold member 2 are selected accordingly.

First, as a sheet-like film, a thermoplastic resin film, here, a thermoplastic polyimide (TPI) film (a Mitsui Toatsu Chemical (trade name: Regulus)), which is an amorphous resin having a thickness of 20 μm, is vertically stretched. 15 horizontal dimensions
A sheet cut into a sheet of 8.0 mm × 300 mm is prepared.

The rubber thin film sheet has a thickness of 3 mm.
A 0 μm fluororubber thin film sheet (Daikin Industries, Ltd. (trade name: Daiel Latex)) has a vertical and horizontal dimension of 75.3.
A sheet cut into a 6 mm × 300 mm sheet is prepared.

The diameter of the columnar member 1 is 24.00.
mm, the length is 330 mm, and the inner diameter of the tubular mold member 2 is 24.20 mm, the outer diameter is 30.0 mm, and the length is 330 mm.

The dimensions of the cylindrical member 1 and the tubular mold member 2 are as follows.
At the time of heating in a heating step to be described later, a design is made in advance so that the dimensional difference between the outer diameter of the cylindrical member 1 and the inner diameter of the tubular mold member is 70 μm at a heating temperature of 400 ° C.

First, after the sheet-shaped film is wound around the cylindrical member 1 once, the fluororubber thin film sheet is placed on the sheet-shaped film, and further wound so that the both ends A overlap as shown in FIG.

The film composed of the above sheet-like film and the fluororubber thin film sheet is referred to as a composite film 4.

The size of the fluororubber thin film sheet is as follows:
Since it is cut to the same size as the circumference of the cylindrical member to be wound, the overlapping both end portions A do not overlap two fluororubber thin film sheets (FIG. 6).

Next, the composite film 4 wound around the cylindrical member 1 is inserted into the hollow portion of the tubular mold member 2 as shown in FIG.

Then, the cylindrical member 1, the composite film 4, and the tubular mold member 2 are inserted into the heating furnace 3 shown in FIG. FIG. 11 schematically shows the details of the device configuration of the heating furnace 3.

In FIG. 11, a support 9 is fixed on a base (not shown) of a heating furnace, a heater 8 is arranged on the support 9, and the object to be heated (a cylindrical member, a film, etc.) is placed inside the heater 8. , A tubular mold member).
The temperature of the heater 8 is controlled by temperature control means (not shown).

One example of the heating conditions in the heating furnace 3 is a heating temperature of 400 ± 5 ° C. and a heating time of 30 ± 1 minute. However, actually, the melting temperature of the film material and the thermal deterioration of the film are taken into consideration. To decide.

In the heating step in the heating furnace, the columnar member 1, the tubular mold member 2, and the composite film 4 change as shown in FIGS.

First, the composite film 4 placed in the heating furnace 3 is wound around the gap between the cylindrical column member 1 and the tubular mold member 2 to form an overlapped portion 15 at both ends (FIG. 6, FIG. 6). 1
3).

The dimensional gap between the outer diameter and the inner diameter of the cylindrical member 1 and the tubular mold member 2 is 200 μm.

From this state, the cylindrical member 1, the composite film 4, and the tubular mold member 2 are heated, and the temperature of each member rises. The columnar member 1 and the tubular mold member 2 begin to expand according to their respective thermal expansion coefficients (FIG. 8).

The composite film 4 starts to soften as the temperature rises. The cylindrical member 1 and the tubular mold member 2 begin to expand as the temperature rises. However, since the thermal expansion coefficient of the aluminum material of the cylindrical member 1 is larger than that of the stainless steel of the tubular mold member 2, the cylindrical member 1 and the tubular mold member 2 are expanded. The dimensional gap between the outer diameter and the inner diameter of No. 2 becomes narrower than the initial low temperature state. Further, as the gap between the cylindrical member 1 and the tubular mold member 2 becomes narrower, the composite film 4 sandwiched therebetween further softens, and the overlapped portions at both ends of the film are welded to each other to be in a joined state. The thickness of the joint is 70 μm (FIG. 10).

The gap between the cylindrical member 1 and the tubular mold member 2 finally becomes the same as the desired film thickness, and the film thickness is made uniform over the entire circumference.

After the elapse of the above-mentioned heating time of 30 minutes, the heating is stopped and the process proceeds to the cooling step (FIG. 12).

In the cooling step, the cylindrical member 1, the composite film 4, and the tubular mold member 2 may be cooled in a natural cooling state after the heating in the heating step is stopped. May be.

In this example, after the heating, the film is immersed in cooling water in a liquid tank and cooled at a cooling rate of 400 ° C./min.

Here, the step of releasing the obtained tubular film will be described.

The first of the releasing steps is to detach the cylindrical member 1 and the tubular member 2 which are integrated.

Further, as a second part of the releasing step, the cylindrical member 1
(FIG. 13 shows an example of a process of fixing the composite film 4 from the columnar member 1 to the support 10 and releasing the composite film 4). Shown).

The film taken out was finished in a tubular (cylindrical) shape, and the portion of the first sheet-like film overlapping portion 15 was also clearly joined.

The usage of the tubular film 4 manufactured by the above method will be described.

After coating the outermost layer of the tubular film obtained in this example with a fluororesin, an image forming apparatus (LBP, laser beam printer) shown in FIG.
An example in which the fixing device 6 is used as the fixing film 6 of the fixing device of FIG.

In FIG. 14, reference numeral 6 denotes a tubular film (fixing film) according to the present invention. 6A is a heater for heating the fixing film 6, and the heater 6A is held by a heater holder 6B.

Reference numeral 6C denotes a stay member, which is formed in a substantially U-shape.

The fixing film 6 is incorporated so as to be fitted on the outer peripheral surfaces of the stay member 6C and the heater holder 6B.

Reference numeral 6D denotes a pressure roller which is driven by driving means (not shown).

As shown in the figure, the fixing device transports and inserts a carrier 6E such as paper carrying toner for forming an image between the fixing film 6 and the pressure roller 6D, and fixes the fixing film received from the heater. While transferring the heat of the toner to the toner, the toner is pressed onto the paper, and the toner is fixed by heating. The fixing film according to the present invention has extremely high uniformity of the film thickness dimension. The thickness of the superposed portion of the sheet-like film was the same as that of the other portions, and extremely high image quality could be obtained without causing uneven heat transfer from the film to the toner. The physical properties of the obtained tubular film were measured as described below.

Comparative Example 1 A cylindrical member 1 and a tubular mold member 2 used in this comparative example are the same as in Example 1.

However, a thermoplastic resin film, in this case, a thermoplastic polyimide (TPI) film which is an amorphous resin having a thickness of 35 μm (trade name: Mitsui Toatsu Chemicals, Inc.) Regulus) was cut into a sheet having a length and width of 158.0 mm × 300 mm.

Here, after the sheet-shaped film is wound around the cylindrical member 1 two times, it is further wound so that both ends A are overlapped as shown in FIG. Next, the sheet-like film wound around the cylindrical member 1 is inserted into the hollow portion of the tubular mold member 2 as shown in FIG.

The subsequent process conditions are the same as in the first embodiment.

After the heating and cooling steps, a tensile test, an internal stress measurement and a thermal analysis measurement were performed on the removed tubular (columnar) film in the same manner as in the first embodiment.

The results will be summarized later, but by forming the composite film as shown in Example 1, first, the tensile strength of the composite film is further improved in comparison with the tubular film of the thermoplastic resin film alone shown in Comparative Example 1. It was shown to improve. Therefore, when used as a fixing film for an image forming apparatus, which is one of the objects of the tubular film of the present invention, the strength of the tubular film itself is higher, and the durability is improved.

Further, the results of the internal stress measurement showed that the use of the composite film reduced the internal stress. Therefore, when the composite tubular film is used as a fixing film, there is an effect that deformation due to heat and wrinkles generated on the film surface are suppressed.

Further, the results of thermal analysis show that the elastic modulus of the composite film is considerably lower than that of the single film, so that when the tubular film is used as a transport belt, it is possible to prevent meandering. There is.

(Embodiment 2) A second embodiment of the present invention will be described. First, a cylindrical member 1 around which a film is wound and a tubular mold member 2 to be inserted are the same as those in Example 1. Reference numeral 1 denotes a cylindrical member made of aluminum having a diameter of 24.00 mm and a length of 330 mm. Is a tubular mold member made of stainless steel. The thermal expansion coefficient of the cylindrical member 1 is 2.4 × 10 ⁻⁵ (/ ° C.), and that of the tubular mold member 2 is 1.2 × 10 ⁻⁵ (/ ° C.). The outer diameter and inner diameter of the cylindrical member 1 and the tubular mold member 2 are set to 450
It is set so that the gap when heated to 50 ° C. becomes 50 μm.

Next, as the sheet-like film, a thermoplastic resin film, here, a thermoplastic polyimide (TPI) film (Mitsui Toatsu Chemical Co., Ltd., trade name: Regulus), which is an amorphous resin having a thickness of 40 μm, is longitudinally formed. , The horizontal dimension is 15
A sheet cut into a sheet of 8.0 mm × 300 mm is prepared.

The rubber particles have an average particle diameter of 5 μm.
Fluoro rubber particles (product of Japan Synthetic Rubber Co., Ltd.) are prepared.
Here, after the sheet-shaped film of the columnar member 1 is wound around once, the fluororubber particles are evenly placed on the sheet-shaped film, and further wound so that both ends A are overlapped as shown in FIG.

Next, the composite film 4 of the fluororubber particles and the sheet-like film was inserted into the hollow portion of the tubular mold member 2 as shown in FIG. And heat for 30 minutes. In this heating step, the columnar member 1 and the tubular mold member 2 are both heated, and the gap distance is reduced due to the difference in the thermal expansion coefficient of the material. Then, the surface of the composite film 4 starts to melt, and the fluororubber particles are gradually pushed into the resin. Thereafter, the fluororubber particles penetrate into the entire film, and substantially partial complexation occurs. Further, both ends of the composite film are welded and joined to form a tube.

After the heating step, the cylindrical member, the composite film and the tubular member are taken out of the heating furnace and cooled. After cooling, the composite film was extracted from the cylindrical member and the tubular mold member. The composite film 4 was finished very finely as if the fluororubber particles were impregnated in the resin. A ± 5 μm tubular film was obtained.

(Comparative Example 2) The cylindrical member 1 and the tubular mold member 2 used in this comparative example are the same as in the first embodiment.

However, a thermoplastic resin film, here a TPI film having a thickness of 50 μm (Mitsui Toatsu Chemical Co., Ltd.)
Product name: Regulus) length and width are 80mm x 300
What was cut | disconnected in the sheet shape of mm was used.

Here, after the sheet-like film is wound around the columnar member 1, it is further wound so that both ends A are overlapped as shown in FIG. Next, the sheet-like film wound around the cylindrical member 1 is inserted into the hollow portion of the tubular mold member 2 as shown in FIG.

The subsequent process conditions are the same as in the first embodiment.

After the heating and cooling steps, the tubular (columnar) film taken out was subjected to a tensile test, an internal stress measurement and a thermal analysis measurement.

As a result, when the tubular film of this comparative example was formed into the composite film shown in Example 2, the tensile strength was further improved. Therefore, the tubular film was used as a fixing film of an image forming apparatus which is one of the purposes of this tubular film. When used, it was shown that the strength of the tubular film itself was higher and the durability was improved.

Further, from the results of the internal stress measurement, the formation of the composite film reduced the internal stress. Therefore, when the composite tubular film is used as a fixing film, there is an effect of suppressing deformation due to heat and wrinkles generated on the film surface.

Further, according to the results of the thermal analysis measurement, since the elastic modulus of the composite film is considerably lower than that of the single film, it is possible to prevent the meandering when the tubular film is used as the transport belt. effective.

(Embodiment 3) A third embodiment of the present invention will be described. As in the above embodiment, 1 is a cylindrical member made of aluminum and having a diameter of 24.00 mm and a length of 330 mm, and 2 is a tubular member made of stainless steel as described above. The thermal expansion coefficient of the cylindrical member 1 is 2.4 × 1
0 ⁻⁵ (/ ° C.), and that of the tubular mold member 2 is 1.2 × 1
0 ⁻⁵ (/ ° C.). Further, a cylindrical member 1 and a tubular mold member 2
The dimensions of the outer and inner diameters are set so that the gap when both are heated to 300 ° C. is 50 μm.

First, as a sheet-like film, a thermoplastic resin film, here, polyether sulfone (PES) (Sumitomo Chemical Industries, trade name: Victrex), which is an amorphous resin having a thickness of 25 μm, is vertically and horizontally oriented. Dimension 15
A sheet cut into a sheet of 8.0 mm × 300 mm is prepared.

Next, a liquid fluororubber (Daikin Industries, trade name: Daiel latex) is prepared in an amount (5 to 10 g) that can be applied to the sheet-like film. Here, after the sheet-shaped film is wound around the columnar member 1 once, the liquid fluororubber is applied evenly on the sheet-shaped film, and further wound so that both ends A are overlapped as shown in FIG. .

A film composed of the above sheet-like film and liquid fluororubber is referred to as a composite film 4.

Next, as shown in FIG.
It is inserted into the hollow part of the tubular mold member 2 and then placed in a heating furnace and heated at 310 ° C. for 30 minutes. In this heating step, both the columnar member 1 and the tubular mold member 2 are heated, and the gap distance is reduced due to the difference in the thermal expansion coefficient of the material.

Next, as the gap between the cylindrical member 1 and the tubular mold member 2 becomes narrower, the composite film 4 sandwiched therebetween is further softened, and the overlapping portions at both ends of the film are welded to each other to be in a joined state. The thickness of the joint is 50 μm.

The gap between the cylindrical member and the tubular mold member finally becomes the same as the desired film thickness, and the film thickness is made uniform over the entire circumference.

After the heating step, the cylindrical member, the composite film and the tubular member are taken out of the heating furnace and cooled. After cooling, the composite film was pulled out of the cylindrical member and the tubular mold member, and the surface of the film was very smooth, and the overall thickness of the composite film was 50 ± 5.
A μm tubular film was obtained.

(Comparative Example 3) The columnar member 1 and the tubular mold member 2 used in this comparative example are the same as in the first embodiment.

However, a thermoplastic resin film, here a PES film having a thickness of 50 μm (Sumitomo Chemical Co., trade name: Victrex) as a sheet-like film wound around the cylindrical member 1 is 158.0 mm in length and width.
A sheet cut into a sheet of × 300 mm was used.

Here, after the sheet-like film is wound around the columnar member 1, it is further wound so that both ends A are overlapped as shown in FIG. Next, the sheet-like film wound around the cylindrical member 1 is inserted into the hollow portion of the tubular mold member 2 as shown in FIG.

The process conditions are the same as in the first embodiment.

After the heating and cooling steps, a tensile test, an internal stress measurement and a thermal analysis measurement were performed on the removed tubular (columnar) film in the same manner as in the third embodiment.

The results show that the composite film shown in Example 3 further improved the tensile strength as compared with the tubular film of the thermoplastic resin film alone shown in Comparative Example 3, and was therefore one of the purposes of this tubular film. When used as a fixing film for an image forming apparatus, it was shown that the strength of the tubular film itself was higher and the durability was improved.

Also, from the results of the internal stress measurement, the formation of the composite film reduces the internal stress. Therefore, when the composite tubular film is used as a fixing film, deformation due to heat and wrinkles generated on the film surface are reduced. Has the effect of suppressing.

Further, from the results of the thermal analysis measurement, the elastic modulus of the composite film is considerably lower than that of the single film, and thus, when the tubular film is used as the transport belt, it is possible to prevent meandering. There is.

Example 4 In this example, in the step of sandwiching an inorganic thin film sheet between thermoplastic resin films, an anaerobic adhesive, here, a vinyl acetate-based anaerobic adhesive, was placed on the inorganic thin film sheet. The effect obtained by sandwiching the two-sided coating by spraying, dipping, brushing, or the like between the thermoplastic resin films and integrally forming the same was examined.

Reference numeral 1 denotes a cylindrical member as a mandrel around which a composite film 4 having an aluminum foil sheet sandwiched between thermoplastic resin films is used. In this example, a solid rod member is used. Reference numeral 2 denotes a tubular or hollow mold member having an inner diameter through which the cylindrical member is inserted.

In this example, aluminum is used for the columnar member 1 and stainless steel is used for the tubular mold member 2. The coefficient of thermal expansion of aluminum is 2.4 × 10
^-5 (/ ° C), the coefficient of thermal expansion of stainless steel is 1.2 × 10
^-5 (/ ° C).

Next, a specific embodiment will be described.

The dimensions of the sheet film are selected according to the inner diameter of the tubular film to be manufactured, and the sizes of the cylindrical member 1 and the tubular mold member 2 are selected accordingly.

First, as a sheet-like film, a thermoplastic resin film, in this case, a polycarbonate (PC) film having a thickness of 15 μm (Engineering Plastics Co., Ltd., trade name: Lexan) is 158.0 mm in length and width.
A sheet cut into a sheet of mm × 300 mm is prepared.

As the inorganic thin film sheet, here, an aluminum foil sheet having a thickness of 20 μm (manufactured by Toyo Aluminum Co., Ltd.)
Thickness of 20μm) and vertical and horizontal dimensions of 75.36mm x 300
Prepare a sheet cut into a sheet of mm.

Next, a mold for winding the thermoplastic resin film and the inorganic thin film sheet will be described. The diameter of the cylindrical member 1 around which the sheet is wound is 24.00 m.
m, the length is 330 mm, and the inner diameter of the tubular mold member 2 is 24.20 mm, the outer diameter is 30.0 mm, and the length is 330 mm.

The dimensions of the cylindrical member 1 and the tubular mold member 2 are such that the difference between the outer diameter of the cylindrical member 1 and the inner diameter of the tubular mold member 2 is 50 μm at a temperature of 150 ° C. during heating in a heating step described later.
m is designed in advance.

Here, as shown in FIG. 1, after the sheet-shaped film is wound around the cylindrical member 1 once, an anaerobic adhesive is applied to both sides. Thereafter, the adhesive-coated aluminum foil sheet is placed on a sheet-like film, and further wound so that both ends overlap as shown in FIG.

Here, the characteristic of the anaerobic adhesive is that it cures by blocking air and exhibits an adhesive effect. Therefore, in the case of the present embodiment, an aluminum foil sheet coated with an anaerobic adhesive is wound between sheet-like films and cured by blocking air.

After being wound, the anaerobic adhesive was cured and the sheet-like film and the aluminum foil sheet were firmly adhered.

A film composed of the above-mentioned sheet-like film and aluminum foil sheet is referred to as a composite film 4.

Further, since the size of the aluminum foil sheet is cut to the same size as the circumference of the cylindrical member 1 to be wound, the overlapping end portions do not overlap two aluminum foil sheets.

Next, the composite film 4 wound on the cylindrical member 1
Is inserted into the hollow part of the tubular mold member 2 as shown in FIG.

Then, the columnar member 1, the composite film 4, and the tubular mold member 2 are inserted into the heating furnace 3 shown in FIG. FIG. 11 shows the detailed structure of the heating furnace 3. In FIG. 11, a support base 10 is fixed on a base (not shown) of a heating furnace, and a heating furnace heater 8 is arranged on the support base 10. The object to be heated (a cylindrical member, a film, a tubular member) is provided inside the heater 8. The heating furnace space 7 in which the mold member is disposed is formed. The temperature of the heater 8 is controlled by temperature control means (not shown).

The heating conditions in the heating furnace 3 are as follows.
0 ± 5 ° C., heating time 30 ± 1 minute.

The heating time is determined in consideration of the melting temperature of the film material and the thermal deterioration of the film.

In the heating step in the heating furnace 3, the columnar member 1, the tubular mold member 2, and the composite film 4 change as shown in FIGS.

First, the composite film 4 placed in the heating furnace 3 is wound around the gap between the mandrel cylindrical member 1 and the tubular mold member 2 so that both ends 6a and 6b form an overlapped portion.

The dimensional gap between the outer diameter and the inner diameter of the cylindrical member 1 and the tubular mold member 2 is 200 μm. From this state, the cylindrical member 1, the composite film 4, and the tubular mold member 2 are heated, and the temperature of each member rises. The columnar member 1 and the tubular mold member 2 begin to expand according to their respective thermal expansion coefficients (FIG. 8).

The composite film 6 starts to soften as the temperature rises. The cylindrical member 1 and the tubular mold member 2 begin to expand as the temperature rises. However, since the thermal expansion coefficient of the aluminum material of the cylindrical member 1 is larger than that of the stainless steel of the tubular mold member 2, the cylindrical member 1 and the tubular mold member 2 are expanded. The dimensional gap between the outer diameter and the inner diameter of No. 2 becomes narrower than the initial low temperature state.

As the gap between the columnar member 1 and the tubular mold member 2 becomes narrower, the composite film 4 sandwiched therebetween further softens, and the overlapped portions of both ends 6a and 6b of the film are welded to each other and joined. The thickness of the joint is 50 μm.
m.

The gap between the cylindrical member 1 and the tubular mold member 2 finally becomes the same as the desired film thickness, and the film thickness is made uniform over the entire circumference (FIG. 10).

After the elapse of the above-described heating time of 30 minutes, the heating is stopped, and the process proceeds to the cooling step (FIG. 12).

For the cooling in the cooling step, the columnar member 1, the composite film 4, and the tubular mold member 2 may be cooled in a natural cooling state after the heating in the heating step is stopped. May be.

In this example, after the above-mentioned heating, the film is immersed in cooling water in a liquid tank, cooled at a cooling rate of 300 ° C./min.

Here, the step of releasing the obtained tubular film will be described in detail.

The first step in the releasing step is as follows.
And detaching the tubular mold member 2.

Further, as the second of the releasing step, the cylindrical member 1
The composite film 4 adhering to the outer surface or the inner surface of the tubular mold member 2 is released (FIG. 13 shows an example of a step of releasing the composite film 4 from the cylindrical member 1).

Here, in the case of the step of releasing the tubular film using the composite film, since the inorganic thin film sheet is interposed between the sheet-like films, the shrinkage of the entire tubular film is suppressed (about 5% → (Reduced to less than 1%), and the release from the cylindrical member becomes easier as compared with the case of releasing the tubular film consisting of only the sheet-like film.

The film taken out was finished in a tubular (cylindrical) shape, and the superposed portions 6a and 6b of the first sheet-like film were also clearly joined.

The usage of the tubular film produced by the above method will be described.

After coating the outermost layer of the tubular film obtained by this embodiment with a fluororesin, the image forming apparatus shown in FIG. 14 (for example, a laser beam printer (L
BP)) shows an example of use as a fixing film 6 of a fixing device.

In the figure, reference numeral 6 denotes a tubular film (fixing film) according to the present invention. 6A is a fixing film 6
The heater 6A is held by a heater holder 6B.

Reference numeral 6C denotes a stay member, which is formed in a substantially U-shape.

[0169] The fixing film 6 is incorporated so as to be fitted on the outer peripheral surfaces of the stay member 6C and the heater holder 6B.

Reference numeral 6D denotes a pressure roller which is driven by driving means (not shown).

As shown in the figure, the fixing device transports and inserts a carrier 6E such as paper carrying toner for forming an image between the fixing film 6 and the pressure roller 6D, and fixes the fixing film received from the heater. Is transferred to the toner and the toner is fixed on the paper by pressing and heating. The fixing film 6 according to the present invention has extremely high uniformity of the film thickness dimension. , The film thickness dimension of the superposed part of the sheet-like film is the same as the others,
The heat transfer from the film to the toner did not become uneven, and a very high quality image could be obtained.

As described above, the strength of the fixing film itself is improved by sandwiching the anaerobic adhesive on both sides of the inorganic thin film sheet between the thermoplastic resin films and improving the adhesion. Also, the thermal conductivity is improved.

Further, the tubular film formed by the present forming method can be used as a transfer belt of an image forming apparatus.
FIG. 15 shows a configuration diagram in which the transfer belt is incorporated.

Reference numeral 11 denotes a photosensitive drum, reference numeral 12 denotes a fixing device, reference numeral 13 denotes a transfer belt, and reference numeral 14 denotes a carrier such as paper. By incorporating the transfer belt formed by this molding method into the transfer unit, a very clear image was obtained because the belt had no thickness unevenness.

(Comparative Example 4) The cylindrical member 1 and the tubular mold member 2 used in this comparative example are made of aluminum and stainless steel as in the fourth embodiment. In addition, cylindrical member 1
The material of the composite film 4 to be wound around is also the same as that of Example 4, and the thickness of the PC film having a film thickness of 15 μm is 20 μm.
A composite film sandwiching an aluminum foil sheet of m was used. However, at that time, an anaerobic adhesive was not applied to the aluminum foil sheet, and an untreated one was used.

Next, the process conditions are the same as those in the fourth embodiment. After the heating and cooling steps, the tubular (column-shaped) taken out is taken out.
A durability test and a thermal conductivity measurement were performed on the film.

First, as a result of a durability test, a composite film in which an inorganic sheet coated with an anaerobic adhesive on both sides as shown in Example 4 was sandwiched between thermoplastic resin films, as compared with the composite film of Comparative Example 4 By using, since the adhesion between the inorganic sheet and the thermoplastic resin film interface is significantly improved, the durability of the composite film of Example 4,
It was further improved as compared with the composite film shown in Comparative Example 4.

As a result of measuring the thermal conductivity, the composite film of Example 4 had higher thermal conductivity than the composite film of Comparative Example 4.

Therefore, when the tubular film is used as a fixing film of an image forming apparatus, which is one of the objects of the tubular film, when the composite film of Example 4 is used, heat conduction is further improved, and the fixing performance is improved.

(Example 5) In this example, an elastic adhesive was used as a functional adhesive applied to an inorganic thin film sheet sandwiched between thermoplastic resin films, and the effect thereof was examined. The elastic adhesive used in this example was a special rubber-modified epoxy resin having excellent thermal shock resistance.

Next, the columnar member 1 and the tubular mold member 2 used in this embodiment are made of aluminum and stainless steel as in the first embodiment. The dimensions of the outer diameter and the inner diameter of the cylindrical member 1 and the tubular mold member 2 are set such that the gap when both are heated to 150 ° C. becomes 50 μm. The material of the composite film 4 wound around the cylindrical member 1 is also the same as that of the first embodiment. A 20 μm aluminum foil sheet (Toyo Aluminum Co., Ltd. A composite film having a thickness of 20 μm was used.

Here, as shown in FIG. 1, after winding a sheet-like film around the cylindrical member 1 once, an aluminum foil sheet coated on both sides with the elastic adhesive (trade name: TB, manufactured by Three Bond Co.) The film is placed on the film, and then wound so that both ends overlap as shown in FIG.

The film composed of the above-mentioned sheet-like film and aluminum foil sheet is referred to as a composite film 4.

Next, as shown in FIG. 2, the composite film surface is wound around the outer peripheral surface of the columnar member 1 so that the winding start and the end overlap. They are inserted into the hollow portion of the tubular mold member 2 and then placed in the heating furnace and heated at 300 ° C. for 30 minutes.

In the heating step, the cylindrical member 1 and the tubular mold member 2 are both heated, causing a difference in dimensional expansion due to a difference in the coefficient of thermal expansion of the material. A tubular shape is formed by the welding operation at both ends.

After the heating step, the cylindrical member 1, the composite film 4, and the tubular member 2 are taken out of the heating furnace and cooled.
After cooling, the composite film 4 was extracted from the cylindrical member 1 and the tubular mold member 2. As a result, a tubular film having a total thickness of 50 ± 5 μm was obtained.

When the obtained tubular film was used as a fixing film, the impact was absorbed by the elastic adhesive, so that the impact resistance of the film was improved and the durability was remarkably improved.

(Comparative Example 5) The columnar member 1 and the tubular mold member 2 used in this comparative example are made of aluminum and stainless steel as in the fourth embodiment. The material of the composite film wound around the cylindrical member is the same as that of the fourth embodiment.
A composite film sandwiching an aluminum foil sheet of m was used. However, at that time, an elastic adhesive was not applied to the aluminum foil sheet, and an untreated one was used.

Next, the process conditions were the same as in Example 5. After the heating and cooling steps, the taken-out tubular (columnar) film was subjected to a durability test and a measurement of thermal conductivity.

First, as a result of a durability test, a composite film in which an inorganic sheet coated with an elastic adhesive on both sides as shown in Example 5 was sandwiched between thermoplastic resin films, as compared with the composite film of Comparative Example 5, was used. By using, the adhesion of the inorganic sheet and the thermoplastic resin film interface and impact resistance are significantly improved, the durability of the composite film of Example 5, compared with the composite film shown in Comparative Example 5, Further improved.

Example 6 In this example, an inorganic adhesive was used as a functional adhesive applied to an inorganic thin film sheet sandwiched between thermoplastic resin films, and its effect was examined. The inorganic adhesive used in this example was an alumina-based inorganic adhesive.

Next, the cylindrical member 1 and the tubular mold member 2 used in this embodiment are made of aluminum and stainless steel as in the fifth embodiment. The dimensions of the outer diameter and the inner diameter of the cylindrical member 1 and the tubular mold member 2 are set such that the gap when both are heated to 150 ° C. becomes 50 μm. The material of the composite film wound around the cylindrical member 1 is also the same as that of Example 4, and a 20-μm aluminum foil sheet (Toyo Aluminum Co., Ltd. 20 μm) was used.

Here, as shown in FIG. 1, a sheet-like film was wound around the cylindrical member 1 once, and then an aluminum foil sheet spray-coated on both sides with an inorganic adhesive (ThreeBond, trade name: TB3732) was formed into a sheet. Put it on the film,
Further, as shown in FIG. 2, the wire is wound so that both ends overlap.

A film composed of the above-mentioned sheet-like film and aluminum foil sheet is referred to as a composite film 4.

Next, as shown in FIG. 3, the composite film is wound around the outer peripheral surface of the columnar member 1 so that the winding start and the end overlap. They are inserted into the hollow part of the tubular mold member 2 and then placed in a heating furnace and heated at 150 ° C. for 30 minutes.
Heat for a minute.

In the heating step, the columnar member 1 and the tubular mold member 2 are both heated, causing a difference in dimensional expansion due to the difference in the coefficient of thermal expansion of the material, thereby reducing the space between the gaps and softening the film by heating and softening the composite film 4. A tubular shape is formed by the welding operation at both ends.

After the heating step, the cylindrical member 1, the composite film 4, and the tubular mold member 2 are taken out of the heating furnace and cooled. After cooling, the composite film 4 was extracted from the cylindrical member 1 and the tubular mold member 2. As a result, a tubular film having a total thickness of 50 ± 5 μm was obtained.

As described above, by using an inorganic adhesive as a functional adhesive applied to an inorganic thin film sheet,
Since there is no thermal deterioration of the adhesive itself and the adhesion does not change,
The heat resistance of the composite film is improved, and when used as a fixing film, it can be used as a fixing film for high-speed rotation.

(Comparative Example 6) The cylindrical member 1 and the tubular mold member 2 used in this comparative example are made of aluminum and stainless steel as in the fifth embodiment. In addition, cylindrical member 1
The material of the composite film to be wound around is also the same as that of Example 6, and 20 μm between PC films having a film thickness of 15 μm.
A composite film sandwiching an aluminum foil sheet was used.
However, at that time, the inorganic adhesive was not applied to the aluminum foil sheet, and an untreated one was used.

Next, the process conditions were the same as in Example 6. After the heating and cooling steps, the tubular (columnar) film taken out was subjected to a durability test and a measurement of thermal conductivity.

First, as a result of a durability test, a composite film in which an inorganic sheet coated with an inorganic adhesive on both sides as shown in Example 6 was sandwiched between thermoplastic resin films, as compared with the composite film of Comparative Example 6 By using, because the adhesion between the inorganic sheet and the thermoplastic resin film interface is significantly improved, the durability of the composite film of Example 6,
It was further improved as compared with the composite film shown in Comparative Example 6.

Therefore, when the tubular film is used as a fixing film of an image forming apparatus, which is one of the objects of the tubular film, use of the composite film of Example 6 improves heat conduction and improves fixing performance.

Example 7 In this example, a conductive adhesive was used as a functional adhesive to be applied to an inorganic thin film sheet sandwiched between thermoplastic resin films, and its effect was examined. As the conductive adhesive used in this example, an epoxy-based heat-curable adhesive in which carbon was uniformly dispersed in an epoxy resin was used.

Next, the columnar member 1 and the tubular mold member 2 used in this embodiment are made of aluminum and stainless steel as in the fifth embodiment. The dimensions of the outer diameter and the inner diameter of the cylindrical member 1 and the tubular mold member 2 are set so that the gap when both are heated to 300 ° C. becomes 50 μm. The material of the composite film wound around the cylindrical member 1 is also the same as that of the fifth embodiment. , A thickness of 20 μm).

Here, as shown in FIG. 1, a sheet-like film is wound around the cylindrical member 1 once, and then an aluminum foil sheet spray-coated on both sides with a conductive adhesive (trade name: TB3301 by Three Bond Co.) is formed into a sheet. Put it on the film,
Further, as shown in FIG. 2, both ends A are wound so as to overlap each other.

A film composed of the above-mentioned sheet-like film and aluminum foil sheet is referred to as a composite film 4.

First, as shown in FIG. 3, the composite film surface is wound around the outer peripheral surface of the columnar member 1 so that the winding start and the end overlap. They are inserted into the hollow part of the tubular mold member 2 and then placed in a heating furnace at 300 ° C. for 30 minutes.
Heat for a minute.

In the heating step, the cylindrical member 1 and the tubular mold member 2 are both heated, and the gap between the members is reduced by the difference in the coefficient of thermal expansion of the material. Become tubular.

After the heating step, the cylindrical member 1, the composite film 4, and the tubular member 2 are taken out of the heating furnace and cooled.
After cooling, the composite film was extracted from the columnar member 1 and the tubular mold member 2. As a result, a tubular film having a total thickness of 50 ± 5 μm was obtained.

As described above, by using a conductive adhesive containing an excellent heat conductive substance such as carbon black in the adhesive as the functional adhesive applied to the inorganic thin film sheet, the thermal conductivity is increased several times. When the film is used as a fixing film, it can be fixed with lower energy.

(Comparative Example 7) The cylindrical member 1 and the tubular mold member 2 used in this comparative example are made of aluminum and stainless steel as in the fifth embodiment. The material of the composite film wound around the cylindrical member is the same as that of the fifth embodiment.
A composite film sandwiching an aluminum foil sheet of m was used. However, at that time, a conductive adhesive was not applied to the aluminum foil sheet, and an untreated one was used. Next, after the heating and cooling steps were performed under the same process conditions as in Example 7, the endurance test and the measurement of the thermal conductivity were performed on the removed tubular (columnar) film.

First, as a result of a durability test, a composite film in which an inorganic sheet having a conductive adhesive applied to both surfaces as shown in Example 7 was sandwiched between thermoplastic resin films, as compared with the composite film of the comparative example. By using, the adhesion of the interface between the inorganic sheet and the thermoplastic resin film was remarkably improved, so that the durability of the composite film of Example 7 was further improved as compared with the composite film of Comparative Example 7.

As a result of the thermal conductivity measurement, the composite film of Example 7 had higher thermal conductivity than the composite film of Comparative Example 7.

Therefore, when the tubular film is used as a fixing film of an image forming apparatus, which is one of the objects of the tubular film, the use of the composite film of Example 7 improves the heat conduction and improves the fixing performance.

Here, the results of physical property measurement performed on each of the tubular films obtained in the above Examples and Comparative Examples are shown in a table. Discussion of the results was mentioned in each description and will not be reprinted.

[0216]

[Table 1]

[0219]

[Table 2] The outline of the durability test will be described. There are two types of endurance tests described here. First, in the idling rotation endurance test, the power of the heater of the fixing unit is turned on (set temperature: 200 ° C.), and the fixing unit (fixing film , A pressure roller), and mainly evaluates the appearance of the fixing film. In the case of a fixing film lacking heat resistance, wrinkles or cracks may be generated on the film surface. The other type is a partial paper passing durability test in which the power of the heater is turned on (set temperature: 200 ° C.) as before, and then 30,000 sheets of special paper (A4 size) are passed. Compared with the above-mentioned idling durability test, the temperature shock of the fixing film surface due to the carrier is intense. In particular, in the case of a resin fixing film having a large coefficient of thermal expansion, wrinkles and cracks are generated on the film surface after passing. there is a possibility.

The following table summarizes the results of these two types of tests.

Various Data (Part 3 Endurance Test)

[0220]

[Table 3]

[0221]

As described above, according to the present invention, a thermoplastic sheet-like film and a composite film comprising a thin film rubber sheet, rubber particles and liquid rubber are wound around a cylindrical member so that both ends thereof are overlapped. By inserting into the tubular mold member and heating them as a whole, the gap between the outer diameter and the inner diameter of the cylindrical member and the tubular mold member is reduced due to the difference in the coefficient of thermal expansion between the materials. A method for producing a tubular or tube-shaped sheet-like film by welding and joining the overlapped portions by softening, by using a composite film, film strength,
Properties such as internal stress relaxation and impact resistance have been significantly improved.

Further, according to the present invention, since the above-mentioned film is a film having high uniformity in thickness, it can be used as a fixing film of an image forming apparatus to obtain a fixing device having more excellent fixing performance.

The tubular film obtained by the above-mentioned various embodiments according to the present invention has a function as a conveyor belt member for high-accuracy conveyance.

As described above, according to the present invention, in the step of winding the composite film around the inner mold, a metal thin film sheet, a glass fiber cloth sheet or a glass fiber cloth sheet coated with a functional adhesive on both sides by spraying, brushing or dipping. In a state in which an inorganic thin film sheet such as a carbon fiber cloth sheet is sandwiched between thermoplastic resin films, and the composite film is wound around a cylindrical member so that both ends thereof overlap with each other,
By inserting into the tubular mold member and heating it, the gap between the outer and inner diameters of the cylindrical member and the tubular mold member is reduced due to the difference in the coefficient of thermal expansion of the material, and the film is laminated by softening. The present invention relates to a method for producing a tubular or tubular sheet-like film by welding and joining the joined portions. By using the functional adhesive, the durability and heat conduction of the tubular film are compared with a composite film without an adhesive. The rate has improved dramatically.

Further, according to the present invention, by using a composite film using the above functional adhesive as a film for an image forming apparatus, it is excellent in the following points.

[0226] 1. By using the above tubular film as a film for an image forming apparatus, an image forming apparatus excellent in heat resistance, impact resistance and the like can be obtained.

[0227] 2. An image forming apparatus using the above tubular film,
In particular, by using as a fixing film, fixing performance,
In addition, a fixing device equipped with a fixing film having remarkably excellent durability and the like could be used, and a clear image could be obtained.

[0228] 3. An image forming apparatus using the above tubular film,
In particular, the transfer belt provided functions of transport and transfer, and exhibited excellent characteristics such as durability and transfer efficiency.

[Brief description of the drawings]

FIG. 1 is an explanatory view when an inorganic sheet coated with a functional adhesive is placed on a thermoplastic resin film and wound around a cylindrical member.

FIG. 2 is an explanatory diagram of an overlapping portion of a composite film wound around a cylindrical member.

FIG. 3 is an explanatory view showing a state in which a composite film wound around a cylindrical member is inserted into a tubular mold member.

FIG. 4 is an explanatory view of a heating furnace in a heating step.

FIG. 5 is an explanatory view of a room-temperature state of an overlapping portion of the sheet-like film in a state where a sheet-like film is wound around a cylindrical member and a tubular mold member is placed thereon, showing that the sheet remains overlapping. I have.

FIG. 6 is an explanatory view of a room temperature condition of an overlapping portion of the sheet-like film in a state where a sheet-like film is wound around a cylindrical member and a tubular mold member is put thereon, and shows that the sheet remains overlapping. I have.

FIG. 7 is an explanatory view of a temperature rising state of an overlapping portion of the sheet-like film in a state where a sheet-like film is wound around a cylindrical member and a tubular mold member is put on the cylindrical member. This indicates that the gap becomes smaller.

FIG. 8 is an explanatory view of a temperature rising state of an overlapping portion of the sheet-like film in a state where a sheet-like film is wound around a cylindrical member and a tubular mold member is placed thereon, This indicates that the gap becomes smaller.

FIG. 9 is an explanatory view of a welded state of an overlapping portion of the sheet-like film in a state where a sheet-like film is wound around a cylindrical member and a tubular mold member is placed thereon, wherein the end portion is fused and the step disappears. It is showing that it is going.

FIG. 10 is an explanatory view of a welded state of an overlapping portion of the sheet-like film in a state where a sheet-like film is wound around a cylindrical member and a tubular mold member is placed thereon, and the end portion is fused to eliminate the step. It is showing that it is going.

FIG. 11 is a detailed explanatory view of a heating furnace.

FIG. 12 is an explanatory diagram of a cooling step.

FIG. 13 is an explanatory diagram of a release step.

FIG. 14 is an explanatory diagram of a fixing device of an image forming apparatus using the tubular film of the present invention.

FIG. 15 is a diagram illustrating a developing, charging, and fixing member of an image forming apparatus using the tubular film of the present invention for a transfer belt.

[Explanation of symbols]

 Reference Signs List 1 cylindrical member 2 tubular mold member 3 heating furnace 4 composite film 6 fixing film 6A fixing film heating heater 6B heater holder 6C stay member 6D pressure roller 6E carrier 7 heating furnace space 8 heating furnace heater 9 heating furnace support base 10 support base DESCRIPTION OF SYMBOLS 11 Photosensitive drum 12 Fixing device 13 Transfer belt 14 Carrier 15 Superposition part of sheet film

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16G 1/14 F16G 1/14 G03G 15/16 G03G 15/16

Claims (13)

[Claims] At least one of the group consisting of one kind of rubber, one kind of elastomer, and one kind of inorganic thin film having a functional adhesive on its surface between two thermoplastic resin sheet films Into a multi-layered sheet-like film, which is wound around a cylindrical member to form a cylindrical laminate, and then the entire cylindrical laminate is softened and shaped to have a uniform thickness accuracy of ± 5 μm. A tubular film for high-precision conveyance characterized by having improved physical properties. 2. The tubular film according to claim 1, wherein one kind of the rubber or one kind of the elastomer is a thin film sheet such as a rubber thin film sheet and an elastomer thin film sheet. 3. The tubular film according to claim 1, wherein one kind of the rubber or one kind of the elastomer is fine particles such as rubber particles and elastomer particles. 4. The tubular film according to claim 1, wherein one kind of the rubber or one kind of the elastomer is a liquid material such as a liquid rubber or a liquid elastomer. 5. The tubular film according to claim 1, wherein the functional adhesive is an anaerobic adhesive. 6. The tubular film according to claim 1, wherein the functional adhesive is an elastic adhesive. 7. The tubular film according to claim 1, wherein the functional adhesive is an inorganic adhesive. 8. The tubular film according to claim 1, wherein the functional adhesive is a conductive adhesive. 9. At least one member of the group consisting of one kind of rubber, one kind of elastomer, or one kind of inorganic thin film having a functional adhesive present on the surface between two thermoplastic resin sheet films. Into a multi-layer sheet-like film, and wrapping it around a cylindrical member to form a cylindrical laminate, and then inserting the entirety of the cylindrical member and the cylindrical laminate through a tubular or hollow mold member. A method for producing a high-precision transporting tubular film having uniformity of film thickness accuracy of ± 5 μm and improved physical properties, wherein the film is softened, shaped, cooled, and removed from the mold member. 10. The method according to claim 9, wherein the thermal expansion coefficient of the tubular or hollow mold member is performed as a combination of materials having a smaller thermal expansion coefficient than that of the cylindrical member. 11. An image forming apparatus such as a copier, a laser printer, or a facsimile, wherein the tubular film according to claim 1 is configured as a film for conveying an image forming medium. 12. The image forming apparatus according to claim 11, wherein the image forming medium transporting film is a fixing film. 13. The image forming apparatus according to claim 11, wherein the film for conveying the image forming medium is a transfer belt.