JP3044002B2 - Fixing part film and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrophotographic copying machine,
The present invention relates to a film for a fixing unit such as a fixing unit and a pressurizing unit, which is used in a heat fixing unit of a toner image of a film fixing system of an apparatus such as a facsimile or a printer.

[0002]

2. Description of the Related Art In a printing apparatus for forming a toner image, such as an electrophotographic copying machine, a facsimile, a printer, etc., at the final stage of printing or copying, the toner of the toner image formed on the recording paper is heated and melted on the recording paper. In general, a heat fixing method for fixing a toner image is used.

In such a heat fixing method, a heat fixing method of a film fixing method using a film-like endless belt has recently been proposed in addition to a heat roller fixing method generally used in the past.

In the fixing method using the endless belt, an endless belt for fixing is passed over a plurality of rollers, another fixing rubber roller is pressed against a predetermined position on the outer surface of the endless belt, and the inner side of the endless belt at the pressed position is pressed. The heater is arranged in contact with the belt. Then, while rotating the endless belt and the roller, the recording paper on which the toner powder image is formed passes between the endless belt and the roller, and the toner is fused on the recording paper. In this fixing method, substantially only the pressure contact portion of the thin film belt is directly heated by the heater, so that the waiting time at the time of turning on the power is almost zero, and this is called an on-demand type heat fixing method. .

Since the above-described mechanism is used in the on-demand heat fixing method, the endless belt used for the heat fixing method has sufficient heat resistance, elasticity, strength, insulation properties on the inner surface of the belt, and separation of the outer surface of the belt. Demands for moldability. In order to respond to this, a belt made of a fixing film composed of two layers, an inner layer made of a heat-resistant resin and an outer layer made of a resin having releasability, is generally used. In order to prevent the offset, there is also used one provided with a layer also serving as a conductive primer layer between the above two layers.

The releasable layer of such a fixing film is very thin due to the demand for thermal conductivity and the like. Usually, a primer layer is provided on the inner heat-resistant resin layer if necessary, and then a fluororesin or the like is formed. It has been manufactured by applying a dispersion, drying and heat-treating.

However, since the releasable layer manufactured by such a manufacturing method is formed by applying a resin, defects such as pinholes and cracks are apt to remain on the surface of the layer, and further high durability and abrasion resistance are obtained. Is required.

[0008]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a fixing part film comprising a heat-resistant resin layer, a conductive primer resin layer, and a release resin layer laminated in this order. An object of the present invention is to provide a film for a fixing portion which shows high durability of a functional layer, particularly, abrasion resistance.

[0009]

As a result of the study of the present inventors, in the above-mentioned film for the fixing portion, the fluororesin molded as a tube on the release layer is applied on the conductive primer resin layer. It has been found that high abrasion resistance of the release layer can be obtained.

Accordingly, the present invention provides a film for a fixing section comprising a heat-resistant resin layer, a conductive primer resin layer and a release resin layer laminated in this order, wherein the heat-resistant resin layer is made of a thermosetting resin. , The release resin layer is the outer diameter of the heat resistant resin layer.
Provided is a film for a fixing portion, which is a layer having a thickness of 20 μm or less formed by applying a tube mainly composed of a fluororesin having an inner diameter of 95% or less on a conductive primer resin layer. Is what you do.

The fluororesin molded as such a tube has a smaller melt index than that used for the fluororesin dispersion, and has higher mechanical strength such as tensile strength and bending resistance.

Accordingly, the fluororesin tube used in the fixing part film of the present invention preferably has a bending resistance of 1,000,000 times or more, for example, 1,000,000 to 2,000,000 times.

The above-mentioned fluororesin tube preferably contains a fluororesin having a melt index of 5 (g / 10 min) or less as a main component.

In the case of a fixing film provided with a conductive primer layer as described above, a releasing layer is not provided on the entire surface of the conductive primer layer in order to eliminate the charging of the film, and a conductive layer is formed at the end. It is also known that the conductive primer layer is exposed, a contact is made at the exposed portion, and the grounding can be performed via a shaft of a roller on which a film is applied. Even in the fixing film having such a configuration, the release layer has been manufactured by applying a dispersion of a fluororesin or the like as described above, and further higher durability has been required.

Therefore, in one embodiment of the film for a fixing portion of the present invention, a release resin layer is not provided at an end portion of the film, and the conductive primer resin layer is exposed. .

The above-mentioned melt index 5 (g / 10
The fluororesin of min) or less can be made into a dispersion, but is not practical because of poor film formability. The above film for a fixing portion of the present invention is manufactured by fusing a fluororesin tube formed by extrusion or the like onto a conductive primer layer and a heat-resistant resin layer.

In the above method for producing a film for a fixing part by fusing a fluororesin tube onto a conductive primer resin layer, the fluororesin already formed into a tube shape is integrally formed on the conductive primer layer. In addition, it has been found that it is effective to perform treatment at a specific temperature after laminating a fluororesin tube on a conductive primer layer in order to perform fusion so that defects such as irregularities do not occur on the surface.

Accordingly, the present invention provides a method for producing a film for a fixing section, comprising laminating a heat-resistant resin layer, a conductive primer resin layer and a release resin layer as described above in this order,
A conductive primer resin layer is formed on a tubular heat-resistant resin layer, a fluororesin tube is laminated thereon, and the treatment is performed at a temperature at least 50 ° C. higher than the melting point of the resin of the fluororesin tube. The present invention provides the manufacturing method.

Further, in order to integrally fuse the fluororesin formed into a tube shape as described above on the conductive primer resin layer and to prevent defects such as irregularities on the surface, the fluororesin tube must be fused. It has also been found that it is preferable to laminate on the heat-resistant resin layer in a state of being extended at a specific ratio in the radial direction.

[0020] Therefore Oite to how the present invention uses a fluororesin tube having a 95% or less of the inner diameter of the outer diameter of the heat-resistant resin layer.

In another preferred embodiment of the method of the present invention, the inner surface of the fluororesin tube is etched before laminating the fluororesin tube on the heat-resistant resin layer.

In still another preferred embodiment of the method of the present invention, an unfolded fluororesin tube is used.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

As shown in the cross section in FIG. 1, the fixing part film of the present invention comprises a heat-resistant resin layer 1 as an inner layer made of a heat-resistant resin, a conductive primer layer 2 as an intermediate layer laminated thereon, and Further, it is constituted by a release resin layer 3 of an outer layer made of a release resin laminated thereon.

In one embodiment of the fixing part film of the present invention, the release resin layer 3 is not formed on the entire surface of the conductive primer layer 2 as shown in FIG. The conductive primer layer 2 is exposed at the end of the film. The width of this exposed part is usually 1 to 5 mm
It is about.

As the heat-resistant resin used for the heat-resistant resin layer, a thermosetting heat-resistant resin is selected in order to obtain particularly high heat resistance. In particular, when a use temperature of 150 ° C. or more is intended, or in a fixing portion or the like, a thermoplastic resin is used, and a fixing film or the like is disadvantageously elongated.

By using a thermosetting heat-resistant resin for the heat-resistant resin layer, the insulation and high heat resistance of the film for the fixing portion can be secured. Examples of such a thermosetting heat-resistant resin include, for example, thermosetting resins such as polyimide, polyamideimide, polybenzimidazole, polybenzoxazole, polyphenylene sulfide, polyetheretherketone, polyethersulfone, and polyetherimide. No. Among these thermosetting heat-resistant resins, thermosetting polyimide and polyamideimide are particularly preferable.

Further, since these resins alone have low thermal conductivity, it is preferable to contain inorganic particles having insulating properties and thermal conductivity.

The substance itself constituting such thermally conductive inorganic particles may be the same as that which has been proposed to be added to the heat-resistant resin layer of the fixing belt, such as boron nitride, Alumina, silicon carbide, potassium titanate, aluminum nitride, mica, silica, titanium oxide, talc, calcium carbonate and the like can be mentioned.
These substances can be used as a mixture of two or more kinds. As a material constituting the thermally conductive inorganic particles,
Boron nitride, alumina, silicon carbide, and aluminum nitride are preferred, and boron nitride is particularly preferred.

The average particle size of the inorganic particles as described above is not particularly limited, and may be the same as the inorganic filler added to a usual resin composition, but a dispersibility and a smooth layer are obtained. From the viewpoint of the above, it is usually about 0.5 to 10 μm, preferably about 0.5 to 7 μm. If it is less than 0.5 μm, the effect of improving the thermal conductivity is small, and irregularities may be formed on the film due to aggregation of particles. If the average particle size of the particles exceeds 10 μm, the mechanical strength required for the heat-resistant resin layer may not be obtained depending on the content.

The content of the heat-conductive inorganic particles in the heat-resistant resin layer is not particularly limited, either.
From the viewpoint of maintenance of mechanical strength and the like, it is usually about 5 to 30% by volume, preferably about 10 to 25% by volume. Within this range, it is possible to improve the thermal conductivity and the rigidity while securing substantially the same flexibility as the layer made of the resin alone. If the content is less than 5% by volume, a sufficient effect of improving thermal conductivity cannot be obtained. If the content exceeds 30% by volume, flexibility and strength become insufficient, and cracks and breakage occur when used as a fixing belt. Easy to occur.

The shape of the thermally conductive inorganic particles may be spherical, flaky (flat), fibrous, or the like. Among them, flat particles have a smooth surface with few irregularities. It is particularly preferable because the stiffness is higher than that of the spherical particle filler.

Although the thickness of the heat-resistant resin layer is not particularly limited, it is usually 10 to 200 μm, preferably 30 to 100 μm.
It is about μm.

On the heat-resistant resin layer, a resin having an adhesive property to the resin of both layers is used in order to enhance the adhesiveness between the heat-resistant resin layer and the release resin layer and to prevent offset due to charging. An intermediate layer (conductive primer layer) made of a substance (conductive filler) is provided.

As the resin used for the conductive primer layer, a mixture of a resin used for a heat-resistant resin layer and a resin used for a release resin layer can be used. It can be composed of a mixture of polyethersulfone and the like. Those obtained by dissolving or dispersing these resins in a solvent are commercially available as primers for fluororesins and can be suitably used in the present invention. As such a commercially available primer for fluororesin, for example, Primer 85 manufactured by DuPont Japan
5-001, 855-023, Teflon 855-02
9. Polyflon EK-1700, Polyflon EK-1800, and Polyflon EK-1900 manufactured by Daikin Industries, Ltd. There is also a conductive primer to which such a fluororesin primer is added a conductive substance as described below,
It can be preferably used in the present invention.

The thickness of the conductive primer layer is usually 0.1
To 20 μm, preferably about 1 to 10 μm.

The kind of the conductive filler used in the conductive primer layer is not particularly limited, and examples thereof include carbon black such as Ketjen black and metal powder such as aluminum. The average particle size of the conductive filler is 0.5 μm in order to obtain stable and uniform conductivity.
The following is preferred.

In order for the conductive primer layer to be able to perform the above-described functions, the conductive primer layer should have a surface resistivity of 1 × 10 ⁶ Ω / □ or less. It is preferable to select the amount of addition.
If the content of the conductive filler is increased, the surface resistivity of the conductive primer layer is decreased. However, if the addition amount is too large, the strength of the fixing portion film is unfavorably affected. The amount of the conductive substance is usually about 0.1 to 5% by weight based on the resin.

Fluororesin is used as the releasing resin constituting the outer layer of the fixing portion film. As the fluororesin, those having excellent heat resistance are preferable so that the fixing belt can be continuously used at a high temperature of about 200 ° C., for example,
Examples include a tetrafluoroethylene resin (PTFE), a tetrafluoroethylene / perfluoroalkoxyethylene copolymer (PFA), and a tetrafluoroethylene / hexafluoropropylene copolymer (FEP). PF
A is particularly preferred.

In the fixing film of the present invention, the melt index (measured according to ASTM D-2116)
Is preferably 5 (g / 10 min) or less, particularly preferably 2 (g / 10 min) or less. Such a fluororesin generally depends on the type of the resin, but generally ranges from 150,000 to 100,000.
It has a molecular weight of about 10,000 and has a higher molecular weight than the fluororesin normally contained in the fluororesin dispersion, and as a film (tube) formed by extrusion or the like, the present invention as described below Is laminated on the heat-resistant resin layer by the method described above, and heat-treated to be integrated with the heat-resistant resin layer.

The fluororesin tube formed by such extrusion molding is different from those formed by applying a fluororesin dispersion on a heat-resistant resin layer, drying and firing, etc. Since there are no surface defects such as cracks and the molecular weight is larger than that of the fluororesin used for dispersion, higher durability such as abrasion resistance can be obtained. Such a fluororesin tube has a bending resistance of 1,000,000 times or more, for example, 1,000,000 to 2,000,000 times (bending according to ASTM D-2176-69 under a load of 1.25 kg using a sample of 13 mm × 90 mm × 0.2 mm). (Measure the number of repeated bends until cracks occur)
It is preferable to have

The fluororesin of the release layer may contain a conductive filler for the same purpose as the conductive primer layer.

The conductive filler used for the release layer may be the same as that used for the conductive primer layer.

The content of the conductive filler is usually about 0.1 to 5% by weight based on the resin. However, if the conductivity of the release resin layer is too high, when the toner on the recording paper comes into contact with the release resin layer of the fixing belt, the charge of the toner flows to the release resin layer, and the recording paper and The suction force between the toner and the toner may be lost. In order to prevent such a phenomenon, the surface resistivity of the outer layer is set to 1 × 10 ¹² to 1 × 10 ¹⁵ Ω / □.
It is preferable that

The thickness of the fluororesin release layer is 20 μm or less.
And Usually 5 μm or more , preferably 10 to 20 μm
It is about. If it is less than 5 μm, it is difficult to form a fluororesin tube, the abrasion resistance is poor, and the life of the film is shortened. If it exceeds 50 μm, the thermal responsiveness deteriorates, and the flexibility of the film decreases, which is not preferable.

Further, a method for producing the fixing portion film of the present invention will be described.

First, a tubular heat-resistant resin layer is formed by a method similar to a known fixing belt. For example, a varnish containing a resin for forming the above-mentioned heat-resistant resin layer or its precursor in a solvent is applied on a cylindrical mold, and the solvent is removed by heat treatment or the like. Thereafter, a resin composition for forming the conductive primer layer is applied, dried, and baked as necessary to produce a heat-resistant resin layer coated with the primer layer.

When the heat-resistant resin is a thermosetting polyimide,
As a precursor of the heat-resistant resin, for example, an aromatic tetracarboxylic acid component and an aromatic diamine component can be used,
These can be reacted in an organic polar solvent to obtain the resin. Examples of the aromatic tetracarboxylic acid component include 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, and pyromellitic dianhydride. There are anhydrides and the like, and these may be used as a mixture. Examples of the aromatic diamine component include diphenyl ether diamines such as 3,3′-diaminodiphenyl ether, 3,3′-dimethoxy-4,4′-diaminodiphenyl ether, and 4,4′-diaminodiphenyl ether;
Diphenylthioethers, diphenylthioether-based diamines such as 4,4′-diaminodiphenylthioether,
Benzophenone diamines such as 4,4'-diaminobenzophenone, and other diphenylmethane diamines such as paraphenylenediamine and metaphenylenediamine can be given. Examples of the organic polar solvent include N-methylpyrrolidone, dimethylformamide, dimethylacetamide, phenol, o-cresol, m-cresol, p-cresol, dimethyloxide and the like.

The resin composition forming the conductive primer layer can be a primer for a fluororesin containing the above-mentioned conductive substance.

The fluororesin tube is laminated on the heat-resistant resin layer and the conductive primer layer formed as described above, and is fused and integrated with the conductive primer layer. Conventionally, a heat-shrinkable fluororesin tube is used to laminate the fluororesin tube on the conductive primer layer.
Methods such as fitting a fluororesin tube having a diameter larger than the conductive primer layer onto the heat-resistant resin layer on which the conductive primer layer is formed, and bringing the fluororesin tube into close contact with the conductive primer layer by heat shrinkage have been adopted. It has been found that it is difficult to obtain sufficient heat shrinkage with a thin fluororesin layer as intended in the above, particularly a fluororesin film having a thickness of 10 to 20 μm, and it is not possible to sufficiently adhere the conductive primer layer and the fluororesin layer. . Therefore, as a result of various studies, a fluororesin tube having a diameter smaller than the diameter of the heat-resistant resin layer on which the conductive primer layer was formed was laminated on the heat-resistant resin layer on which the conductive primer layer was formed, and then at a specific temperature. It was found that the heat treatment can sufficiently fuse and integrate the fluororesin tube to the conductive primer layer without causing defects such as wrinkles on the surface of the fluororesin tube.

In order to laminate a fluororesin tube having a smaller diameter than the heat-resistant resin layer on which the conductive primer layer is formed as described above on the heat-resistant resin layer on which the conductive primer layer is formed, fluorine Expand the resin tube in the radial direction to the extent that it does not cause permanent elongation, insert a heat-resistant resin layer with a conductive primer layer formed in the fluororesin tube between them, and then expand the expanded fluororesin tube What is necessary is just to return to a state.

Various methods are conceivable for fixing the fluororesin tube in a radially expanded state in order to insert the heat-resistant resin layer having the conductive primer layer formed therein into the fluororesin tube. As shown in a schematic cross-sectional view (side view) in FIG. 3, the diameter is larger than the diameter of the heat-resistant resin layer in which the conductive primer layer is formed in the cylindrical mold 4 having an inner diameter slightly larger than the intended diameter of the conductive primer layer. A fluororesin tube 5 having a small inner diameter is passed through, both ends of which are folded back to the outside of the mold, and the tube 5 is sucked through a hole 6 provided in the mold 4 to reduce the pressure between the mold 4 and the tube 5 to reduce the tube 5 By closely adhering to the mold 4, it can be stretched in the radial direction, expanded, and fixed.

Thereafter, the laminate 8 of the heat-resistant resin layer 1 and the conductive primer layer 2 formed on the metal core 7 is inserted into the tube 5, and the pressure between the mold 4 and the tube 5 is released. The tube 5 is brought into close contact with the conductive primer layer by returning to the original diameter by shrinkage due to the restoring force of the tube 5. At this time, since the original inner diameter of the fluororesin tube 5 is smaller than the outer diameter of the conductive primer layer, the fluororesin tube 5 adheres to the conductive primer layer in a state of being extended and expanded in the radial direction.

When the fluororesin tube is brought into close contact with the conductive primer layer by the contraction force of the fluororesin tube,
The inner diameter of the fluororesin tube is 95% or less of the outer diameter of the conductive primer layer, preferably 93%.
It was found that sufficient adhesion between the two layers could be obtained together with the subsequent heat treatment by setting as follows. However, if the elongation is too large, the fluororesin tube will be permanently plastically deformed and a shrinkage force cannot be obtained, so the inner diameter of the fluororesin tube is 80% of the outer diameter of the heat-resistant resin layer on which the conductive primer layer is formed. That's all.

When an exposed portion of the conductive primer layer is provided at the end of the film, a fluororesin formed in a tube shape as described above is laminated on the portion excluding that portion, or the entire surface of the conductive primer layer is Then, the exposed portion is formed by laminating the fluororesin formed into a tube shape as described above, and then removing the exposed portion of the fluororesin layer.

Thereafter, the heat-resistant resin layer on which the conductive primer layer formed as described above is formed and the fluororesin tube are heated and fired to fuse and integrate the fluororesin tube with the conductive primer layer. At this time, it has been found that sufficient fusion can be obtained by heating at a temperature at least 50 ° C. or higher, preferably 70 ° C. or higher than the melting point of the fluororesin used. For example, when the fluororesin is PFA,
Since its melting point is about 310 ° C., it is heated at a temperature of 360 ° C. or more.

The heating time depends on the type of fluororesin, the thickness of the layer,
Depending on the thickness, material, heating temperature, etc. of the core, PFA should be 3
When heating at 60 ° C., it takes about 20 to 40 minutes.

After the above heat treatment, the integrated laminated film is removed from the cored bar to obtain the fixing film of the present invention.

In the above-mentioned production, the adhesive strength between the two layers can be increased by etching the inner surface of the fluororesin tube in advance before laminating the fluororesin tube on the heat-resistant resin layer having the conductive primer layer formed thereon. . Etching can be performed by a conventionally known etching method, and can be performed by chemical etching such as sodium-naphthalene method and liquid ammonia method, and physical etching such as excimer laser method and low-temperature plasma method.

As the fluororesin tube used for producing the fixing film of the present invention, a commercially available fluororesin tube can be used, and such a commercially available fluororesin tube is folded into a tape shape. It is often distributed in a wound state. In such a tube, two folds are provided on the circumference in the length direction, and a portion outside the fold is in an extended state. When this is laminated on the heat-resistant resin layer on which the cylindrical conductive primer layer is formed, the extended portion is likely to remain as a linear concave portion on the surface of the fluororesin layer, but the surface of the surface caused by such a fold is likely to remain. Defects can also be solved by the method according to the invention, as described above, since the tube is sufficiently stretched. However, a relatively thick fluororesin layer (for example, 30 to 10)
(About 0 μm), it is preferable to use an unfolded fluororesin tube.

The fixing portion film of the present invention produced as described above has a particularly excellent abrasion resistance because it has a release resin layer derived from a fluororesin tube obtained by extrusion molding. , Pinholes, cracks, minute irregularities, etc., cannot be avoided, and a significantly longer service life can be obtained as compared with a conventional film produced by coating.

[0062]

EXAMPLES Hereinafter, the present invention will be further described with reference to Examples and Comparative Examples, but the present invention is not limited to only these Examples.

Example 1 A commercially available varnish containing a polyimide precursor (U Varnish S, manufactured by Ube Industries) was applied on a cylindrical metal core, and the inner diameter was 26 mm.
Was mounted on a core body and allowed to fall naturally to obtain a coating film.
The obtained coating film was heated to 300 ° C. for 30 minutes, and after cooling, pulled out of the core, the thickness was 50 μm, the outer diameter was 25 mm and the length was 230
mm polyimide tube was obtained.

A conductive primer (855-023, manufactured by DuPont) having a thickness of 5 μm was placed on the polyimide tube.
And baked at 150 ° C. for 10 minutes.

A cylindrical stainless steel shaft having a diameter of 24.97 mm was inserted into the polyimide tube provided with the conductive primer layer to obtain a support.

On the other hand, the same shape as that shown in FIG.
A PF having an inner diameter of 23.3 mm (about 93% of the outer diameter of the polyimide tube), a length of 280 mm, and a thickness of 10 μm inside a mold having an inner diameter of 26.5 mm and a hole having a diameter of 1 mm at the end.
A tube (450HP-J, manufactured by Du Pont-Mitsui Fluorochemicals, made of PFA with a melt index of 2 g / 10 min) was passed through the mold and fixed at both ends.
The PFA tube is expanded by reducing the pressure through the hole of the mold,
It was adhered to the inner surface of the mold.

Thereafter, the shaft equipped with the polyimide tube was inserted into a mold, and the vacuum was released to cover the PFA tube with the polyimide tube. Thereafter, the PFA tube at one end of the polyimide tube was removed with a width of 3 mm to provide an exposed portion of the conductive primer layer.

This was heat-treated at 380 ° C. for 30 minutes to obtain a fixing film of the present invention. The thickness of the release resin layer of the obtained film for the fixing portion was 10 μm.

Example 2 In the same manner as in Example 1, a polyimide tube (outer diameter: 30 m
m, a length of 320 mm, and a thickness of 70 μm), and a conductive primer (855-029, manufactured by DuPont) is spray-coated on the surface so as to have a thickness of 5 μm.
Baking treatment was performed at 10 ° C. for 10 minutes.

In the same manner as in Example 1, a PFA tube (450HP-J, Mitsui-Dupont Fluorochemical) having an inner diameter of 28 mm (about 93% of the outer diameter of the polyimide tube provided with the conductive primer), a length of 370 mm, and a thickness of 10 μm was used. (Made of PFA having a melt index of 2 g / 10 min) to form an exposed portion of the conductive primer layer, which was fused to obtain a fixing film of the present invention. The thickness of the release resin layer of the obtained film for the fixing portion was 10 μm.

COMPARATIVE EXAMPLE After forming a polyimide tube and applying a primer in the same manner as in Example 1, the exposed portion of the conductive primer layer was masked to form a PFA resin dispersion (855-104, manufactured by DuPont). The film was applied by spraying, and the film was heat-treated at 380 ° C. for 30 minutes to obtain a film for a fixing portion. The thickness of the release resin layer of the obtained film for the fixing part was about 10 μm.

When the MI of PFA contained in the PFA resin dispersion was separately measured, it was 13 g / 10 min.
Met.

The fixing unit films obtained in Examples and Comparative Examples obtained above were incorporated into a printer, and an image test by printing and a durability test by paper passing (paper passing speed: A4 paper: 12 sheets / min)
Was done. The exposed portion of the conductive primer layer of each fixing film was grounded to prevent frictional charging due to paper passing. The results are shown in the table below.

[0074]

[Table 1] From the above results, the fixing film of the present invention has significantly improved durability including abrasion resistance as compared with a fixing film having a release layer formed by applying a fluororesin dispersion. It is clear that Further, when the exposed portion of the conductive primer layer is provided, the portion can be grounded, so that there is no occurrence of offset due to triboelectric charging.

[0075]

According to the film for a fixing part of the present invention, a facsimile, a printer, etc., having a significantly improved abrasion life as compared with a conventional fixing film and having excellent durability can be provided. There is no offset.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a fixing unit film of the present invention.

FIG. 2 is a schematic side view of one embodiment of the fixing portion film of the present invention.

FIG. 3 is a schematic cross-sectional view illustrating a method for manufacturing a fixing film of the present invention.

[Explanation of symbols]

 1. . . Heat resistant resin layer 2. . . 2. conductive primer layer . . Release resin layer 4. . . Mold 5. . . Fluororesin tube 6 . . 6. Hole in mold . . Core metal 8. . . Laminated body of heat-resistant resin layer and conductive primer layer

Continuation of front page (56) References JP-A-6-318007 (JP, A) JP-A-2-162382 (JP, A) JP-A-3-210587 (JP, A) JP-A-3-25471 (JP) JP-A-5-72934 (JP, A) JP-A-4-197622 (JP, A) JP-A-6-258969 (JP, A) JP-A-7-199691 (JP, A) 10-186920 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 13/20 G03G 15/20

Claims (8)

(57) [Claims] 1. A fixing unit film comprising a heat-resistant resin layer, a conductive primer resin layer, and a release resin layer laminated in this order, wherein the heat-resistant resin layer is made of a thermosetting resin,
The releasable resin layer is 95% or less of the outer diameter of the heat-resistant resin layer.
A film for a fixing part, which is a layer having a thickness of 20 μm or less formed by applying a tube mainly composed of a fluororesin having a diameter on a conductive primer resin layer. 2. The fixing part film according to claim 1, wherein the fluororesin tube has a refraction resistance of 1,000,000 times or more. 3. The fixing part film according to claim 1, wherein the fluororesin tube is mainly composed of a fluororesin having a melt index of 5 (g / 10 min) or less. 4. The fixing unit according to claim 1, wherein a release resin layer is not provided at an end of the film, and the conductive primer resin layer is exposed. the film. 5. A method for producing a film for a fixing part, comprising laminating a heat-resistant resin layer, a conductive primer resin layer, and a release resin layer according to claim 1 in this order, A conductive primer resin layer is formed on a tubular heat-resistant resin layer, and an inner diameter of 95% or less of an outer diameter of the heat-resistant resin layer.
In a state where the fluororesin tube having
Forming conductive primer resin layer inside fluororesin tube
Inserting the heat-resistant resin layer
The method according to claim 1, wherein a fluorine tube is laminated on the polymer resin layer and treated at a temperature at least 50 ° C. higher than the melting point of the resin of the fluorine resin tube. 6. The method according to claim 5, wherein the fluororesin tube is laminated except for the exposed portion of the conductive primer resin layer. 7. The method according to claim 5, wherein an inner surface of the fluororesin tube is etched before laminating the fluororesin tube on the heat-resistant resin layer. 8. The method according to claim 5, wherein an unfolded fluororesin tube is used.