JP2000351466A - Carrying belt, fixing device, intermediate transfer body and manufacture of belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent flapping at stretching time by providing a resin endless belt-like base material, and setting a carrying directional fluctuation in a width directional average thickness crossing in the carrying direction of the base material not more than the specific ratio to an average thickness of the whole base material surface. SOLUTION: A fixing belt 52 and an intermediate transfer body 2 are formed of an endless belt including a heat resistant resin base material. In respective ones of the fixing belt 52 and the intermediate transfer body 2, a carrying directional fluctuation in a width directional average thickness crossing in the carrying direction of the base material is set so as to satisfy a fluctuation condition being ±5% or less to an average thickness of the base material. In the fixing belt 52 and the intermediate transfer body 2, since the respective base materials satisfy this fluctuation condition, a flapping quantity of the belt can be restrained up to a practically unproblematic quantity even when stretched on shafts not less than two shafts. Recording paper 41 recording an unfixed toner image can be carried by keeping an unmeandering/nondeviating smooth surface of the belt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transport belt for transporting recording paper and the like in an image forming apparatus such as a copying machine, a printer, a facsimile, etc., and to transport a toner image transferred at a primary transfer position to a secondary transfer position. Transfer device as an endless belt, a fixing device having a fixing belt for fixing an unfixed toner image on the recording paper on the recording paper while moving the recording paper, and a belt manufacturing method for producing the endless belt About.

[0002]

2. Description of the Related Art Conventionally, a photoreceptor for forming a toner image, a transfer device for transferring the toner image formed on the photoreceptor onto a recording sheet, and a recording apparatus for recording the toner image transferred on the recording sheet. 2. Description of the Related Art An endless belt made of a heat-resistant resin is used in an image forming apparatus having therein a fixing device for fixing on paper. For example, in this image forming apparatus, a toner image formed on the photoreceptor is often primarily transferred from a primary transfer position in contact with the photoreceptor to carry the toner image and transfer the toner image to the transfer device. An endless belt-shaped intermediate transfer body that is transported to the next transfer position is used.
Further, the fixing device has two rotating members that form a fixed image by fixing the unfixed toner on the recording sheet while conveying the recording sheet on which the unfixed toner is loaded, and often includes the two rotating members. A fixing belt having an endless base material made of heat-resistant resin on at least one of the bodies is used. In this image forming apparatus, a transport belt is used to transport a recording sheet or the like.

[0003] First, a conventional technique of a fixing device will be described. Conventionally, in a fixing device, an elastic layer having elasticity and a release layer for improving the releasability of a toner image are formed on a metal hollow pipe having a heating source in at least one of the two rotating bodies. There is a type that employs a pair of rolls in which the rolls face each other. A fixing device having such a pair of rolls transfers a toner image while moving the recording sheet by the pair of rolls through a recording sheet having an unfixed toner image adhered to a nip region formed between the rolls of the pair of rolls. Fixing is performed by a so-called roll-roll fixing method in which heating and pressing are performed.

In order to speed up the fixing performed by the roll-roll fixing method, the above-mentioned roll-roll pair is compensated for by reducing the time required for heating and pressing the toner image by the above-mentioned roll-roll pair. It is necessary to increase the width of the nip area in the direction in which the recording paper moves. In order to increase the width, it is conceivable to increase the load between the pair of rolls, adopt a roll having a large outer diameter, and increase the thickness of the elastic layer of the roll. However, when the load between the pair of rolls is increased, the elastic layer of the pair of rolls deteriorates in durability, and the deflection and deformation of the pair of rolls increase, so that the nip width of the pair of rolls increases in the axial direction of the roll. In this case, the recording paper passing between the pair of rolls may be wrinkled, or a fixed image fixed on the recording paper may have uneven fixing. In order to prevent the roll deflection and deformation, there is a method of increasing the thickness of the metal pipe, which can be dealt with. However, according to this method, the so-called warm-up time for raising the temperature of the roll surface to a fixing temperature becomes long. Occurs. In addition, if a roll having a large outer diameter is used or the thickness of the elastic body is increased, problems such as an increase in warm-up time, an increase in the size of the apparatus, and an increase in component costs occur.

In order to solve these problems, recently, at least one of a pair of rolls of a fixing device of a roll-roll system has been replaced with a fixing belt having an endless belt made of a heat-resistant resin as a base material. A fixing device of a fixing system or a belt-belt fixing system has been put into practical use. In these fixing devices of the roll-belt fixing method or the belt-belt fixing method, the fixing belt is stretched with a predetermined tension on two or more rotating stretching shafts, and the fixing belt is opposed to the fixing belt. It has a wide nip area by applying pressure to a roll or another fixing belt, and has the advantages of being small and having a short warm-up time.

[0006]

However, in the fixing belt stretched in this manner, irregularities are generated on the belt surface between the stretch shafts, which undulate in the axial direction of the stretch shaft. Due to the generation of the wavy irregularities of the fixing belt, the following problems occur in that the adhesion between the fixing belt and the recording paper on the fixing belt becomes uneven, and the image is shifted due to the unevenness. There is a problem that the recording paper on the fixing belt flaps and the unfixed toner on the recording paper scatters, and the unevenness of the adhesion between the tension shaft and the fixing belt causes the meandering / single belt. The problem of shift occurs.

[0007] To solve the problem of meandering / bias of the belt, the circumferential length at the center and the circumferential length at the end of the belt in the width direction are set to 0.
A circumferential length difference is given at a rate of 07% to 20%, and a driving roll having a drum shape or a reverse drum shape adapted to the shape of the belt having the circumferential length difference is used to change the shape of the nip width in the roll axis direction. A method of preventing meandering / skew of the belt while adjusting (JP-A-3-110137) is known. However, even if a belt and a driving roll having such a shape are used,
Still, it is not possible to sufficiently suppress the occurrence of wavy irregularities on the belt surface between the tension axes of the belt.

The generation of the wavy irregularities generated in the axial direction of the belt surface between the tension axes of the belt is caused not only in the fixing belt but also in the tension of two or more axes such as an intermediate transfer member and a transport belt. This also occurs in a general resin endless belt stretched around a shaft. Therefore, such a general resin endless belt also has the above-mentioned problems such as fluttering of the recording paper, toner scattering, belt meandering / skew, and image deviation.

In view of the above circumstances, the present invention is directed to a conveyor belt and an intermediate transfer member, which are belts that are prevented from waving when being stretched on two or more axes and maintain a smooth surface.
A fixing device provided with a belt that maintains a gentle surface that is prevented from waving when stretched over two or more axes, and a smooth surface that is prevented from waving when stretched over two or more axes And a belt manufacturing method for manufacturing a belt in which a belt is maintained.

[0010]

A transport belt according to the present invention that achieves the above object is provided with a material to be transported placed on a plurality of shafts and circulated and moved in a predetermined transport direction. An endless conveyor belt to be conveyed, having a base material in the form of a resin endless belt, and a variation in an average thickness in a width direction of the base material in a width direction intersecting with the conveyance direction, the variation in the conveyance direction, the entire surface of the base material. The thickness is not more than ± 5% of the average thickness.

[0011] The transport belt of the present invention may be arranged such that the plurality of shafts have at least 0.5 N and 50 N per 1 mm ^{2 of} unit sectional area.
It is preferable that it is stretched with the following tension.

It is preferable that the transport belt of the present invention is formed using a polyimide resin as a material.

The fixing device of the present invention that achieves the above object is
A fixing device having two rotating members that rotate while contacting each other, and fixing the toner image on the recording sheet at a position where the two rotating members contact while moving the recording sheet to which the toner image adheres. At least one of the two rotating members comprises a fixing belt having a resin-based endless belt-shaped base material stretched around a plurality of shafts and circulated in a predetermined conveying direction; The average thickness in the width direction of the material in the width direction intersecting the transport direction is not more than ± 5% of the average thickness of the entire surface of the base material.

In the fixing device according to the present invention, the fixing belt may be mounted on the plurality of shafts at a ratio of 0.5 to 1 mm ² per unit sectional area.
It is preferable that it is stretched with a tension of N or more and 50 N or less.

Further, in the fixing device according to the present invention, the fixing belt may include any one of an elastic layer having elasticity and a release layer for improving the releasability of a toner image on the surface of the base material. Alternatively, two layers of the elastic layer and the release layer covering the elastic layer are formed, and the total thickness of the layers formed on the base material is 5 μm or more and 5 μm or more.
It is preferably not more than 00 μm.

Further, in the fixing device of the present invention, it is preferable that the base material is formed using a polyimide resin as a material.

The intermediate transfer member of the present invention, which achieves the above object, is stretched around a plurality of shafts and circulated in a predetermined transport direction. A resin endless belt-shaped intermediate transfer body that conveys the toner image to a recording medium at the secondary transfer position at the secondary transfer position, wherein the average thickness in the width direction intersecting the conveyance direction varies in the conveyance direction. Is not more than ± 5% of the average thickness of the entire surface of the intermediate transfer member.

The intermediate transfer member of the present invention is preferably formed using a polyimide resin as a material.

According to the belt manufacturing method of the present invention which achieves the above object, both the inner wall surface and the outer wall surface are formed in a cylindrical shape, and the distance between the center axis of the inner wall cylinder and the center axis of the outer wall cylinder is reduced. A mold having a diameter of 120 μm or less is prepared, a resin solution is put in the mold, and the mold is rotated around a cylindrical center of an outer wall as a center of rotation, thereby manufacturing an endless resin belt. And

[0020]

Embodiments of the present invention will be described below.

FIG. 1 is a schematic configuration diagram of an image forming apparatus of the present embodiment to which the conveying belt, the intermediate transfer member, and the fixing device of the present invention are applied.

The image forming apparatus of this embodiment shown in FIG. 1 has a fixing device 5 having an intermediate transfer body 2 and a fixing belt 52.
Having. Details of the intermediate transfer body 2, the fixing device 5, and the fixing belt 52 will be described later.

The image forming apparatus according to the present embodiment includes a photosensitive member 1 as a toner image carrier, a developing section 6 for supplying toner to the photosensitive member 1, and a toner circulating to transfer the toner on the photosensitive member 1 from the primary transfer position. An endless belt-shaped intermediate transfer member 2 made of only a heat-resistant resin substrate to be transported to a secondary transfer position, and a conductive roll 25 serving as a transfer electrode for transferring the toner on the photosensitive member 1 to the intermediate transfer member 2 at the primary transfer position , At the secondary transfer position, of the intermediate transfer body 2,
The bias roll 3, which is a transfer electrode provided on the surface side on which the toner image is carried,
, A backup roll 22, which is disposed to face the backup roll 22, an electrode roll 26 which rotates while being pressed against the backup roll 22, support rolls 21, 23 which support the intermediate transfer body 2 and guide circulation of the intermediate transfer body 2, 24, a recording sheet 41 as a transfer medium, a tray 4 for supplying the recording sheet 41, a feed roll 42 for feeding the recording sheet 41 from the tray 4, a transport path 43 as a path through which the transferred recording sheet 41 is transported, and It has a layer structure in which an endless belt made of a heat-resistant resin is provided with an elastic layer having elasticity on the outer peripheral surface of the base and a release layer covering the elastic layer and improving releasability. Fixing device 5 provided with fixing belt 52
Having.

The operation of the image forming apparatus will be described below.

The photosensitive member 1 rotates in the direction of arrow A, and its surface is uniformly charged by a charging section (not shown). The charged photoreceptor 1 is irradiated with a laser by an image writing unit (not shown) to form an electrostatic latent image.

This electrostatic latent image is visualized by the toner supplied by the developing unit 6, and a toner image T is formed. The toner image T reaches the primary transfer position where the conductive roll 25 is arranged by the rotation of the photoconductor 1, and a voltage having a polarity opposite to that of the electric charge of the toner of the toner image T is applied from the conductive roll 25. Is electrostatically attracted to the intermediate transfer member 2. Since the intermediate transfer member 2 moves in the direction of arrow B while contacting the surface of the photoconductor 1 at the primary transfer position, the toner images T on the photoconductor 1 are sequentially attracted onto the intermediate transfer member 2 as the toner image T moves, and Transcribed. The toner image transferred onto the intermediate transfer member 2 is conveyed to the secondary transfer position where the bias roll 3 is installed by circulation of the intermediate transfer member 2.

The recording paper 41 is fed from the recording paper bundle stored in the recording paper tray 4 by the feed roll 42 between the intermediate transfer body 2 at the secondary transfer position and the bias roll 3 at a predetermined timing. You. At the secondary transfer position, the intermediate transfer member 2 on which the toner image is placed is biased by a bias roll 3
While being pressed against the recording paper 41 by the backup roll 22, the backup roll 2
When a voltage having the same polarity as the polarity of the toner image is applied through 2, the toner image is attracted to the recording paper 41. Since the intermediate transfer body 2 moves so as to circulate in the direction of arrow B together with the recording paper 41 at the secondary transfer position, the toner image on the intermediate transfer body 2
The second transfer is performed by successively adsorbing the prints 1 to 1.

The recording paper 41 onto which the toner image has been transferred is conveyed to the fixing device 5 through a conveyance path 43. Recording paper 41
The upper toner image is pressed / heated by the fixing device 5 and fixed on the recording paper 41 as shown in detail below with reference to FIG.

FIG. 2 is a schematic configuration diagram of the fixing device of the present embodiment.

The fixing device 5 includes an aluminum hollow roll 51a having a heating source including a halogen lamp therein.
Liquid silicone rubber (Liquid silicone) laminated on the surface of the aluminum hollow roll 51a
Rubber layer 51b and elastic layer 5
1b heat-resistant release oil-resistant layer 51 coated with fluoro rubber
c, which is driven so as to rotate in the direction of arrow C. The fixing roll 51 having the layer structure described in the description of FIG. 1 is driven and circulates in the direction of arrow D. A driven fixing belt 52, a pressure pad 56 formed by integrally molding silicone rubber on a metal base and pressing the fixing belt 52 against a fixing roll 51 to form a nip region N having a wide nip width, and support the fixing belt 52. A first support roll 54, a second support roll 55 positioned upstream of the nip area N in the circulation of the fixing belt 52 to support the fixing belt 52 and to preheat the fixing belt 52 with a heating unit; A pressure roll 53 that supports the fixing belt 52 is provided downstream of the circulation of the fixing belt 52 from the region N. A portion of the fixing belt 52 that is in contact with the nip area N is stretched between a second support roll 55 and a pressure roll 53, and the pressure roll 53 is pressed toward the center of the fixing roll 51 by a coil spring (not shown). .

The fixing device 5 includes a cleaning unit 57 that contacts the fixing roll 51 to wipe off residual toner on the surface of the fixing roll 51, and a release agent that contacts the fixing roll 51 upstream of the fixing nip to apply a release material. Uniform application means 5
8 is provided.

The operation of the fixing device 5 will be described below.

Recording paper 41 with unfixed toner on its surface
Is the second of the fixing belt 52 via the conveyance path 43 of FIG.
Is transported to a portion above the supporting roll 55. Recording paper 41
Is preheated by the second support roll 55 together with the unfixed toner on the recording paper. The fixing belt 2 has a portion extending horizontally from the second support roll 55 to the nip area N. The recording sheet 41 is conveyed to the nip area N in the direction of arrow E by the horizontally extending portion. When the recording paper 41 to which the unfixed toner image adheres passes through the nip area N, the fixing roll 51 heats and pressurizes the unfixed toner image so that the unfixed toner image is recorded on the recording paper 41.
Fix on top. Since the release agent is applied to the fixing roll 51 by the release agent uniform application unit 58, the unfixed toner image is efficiently fixed to the recording paper 41, but is not fixed to the recording paper 41, If there is toner attached to the surface of the cleaning device, the toner is
7 wiped off.

As described above, in the image forming apparatus of this embodiment, the fixing belt 52 and the intermediate transfer body 2 are used. As described above, the fixing belt 52 and the intermediate transfer member 2
Are endless belts each including a heat-resistant resin base material which is stretched around a plurality of rotating shafts and circulated and moved in a predetermined transport direction, and which moves a material to be transported in the predetermined transport direction. And also corresponds to the transport belt according to the present invention. Hereinafter, the endless belt including the heat-resistant resin base material that is stretched around the plurality of rotating shafts and circulated and moved in a predetermined transport direction in this manner is referred to as a stretch belt.

The present inventors have conducted intensive studies on the amount of wavy irregularities in the direction of the rotational axis on which the stretch belt is stretched, and as a result, have found that the stretch belt has wavy unevenness. It has been found that the amount can be suppressed by minimizing the variation in the transport direction of the average thickness of the base material of the stretched belt in the width direction intersecting the predetermined transport direction. The tension belt of the present embodiment, that is, the fixing belt 52 and the intermediate transfer member 2 each have a variation in the average thickness of the base material included in the tension belt in the width direction crossing the conveyance direction in the conveyance direction. This satisfies the variation condition of ± 5% or less with respect to the average thickness of the entire surface.

As will be described later in the examples, the fixing belt 52 of the present embodiment can be used even when the fixing belt 52 is stretched on two or more shafts by satisfying the variation conditions. The amount of undulation is suppressed to a level that does not cause a problem in practical use, and the recording paper 41 on which the unfixed toner image is placed is smoothly transported while maintaining a smooth surface without meandering / unevenness of the belt. The image fixed on the recording paper 41 without scattering the toner of the image is provided with good fixing without any deviation. Also, the intermediate transfer body 2 of the present embodiment also satisfies the above-mentioned variation condition, maintains a smooth surface even when stretched on two or more axes, and reduces the amount of waving of the belt without a practical problem. The smooth transfer of the toner image without the meandering / bias of the belt, the toner of the toner image is not scattered, and a good transfer in which the transferred toner image is not shifted in the secondary transfer is provided.

The heat-resistant resin material constituting the base material of the tension belt of the present embodiment includes aromatic polyimide using biphenyltetracarboxylic dianhydride (BPDA) as a raw material monomer, and pyromellitic dianhydride. A polyimide resin such as an aromatic polyimide using (PMDA) as a raw material monomer, a polyamide resin, a polyamideimide resin, a fluororesin represented by polytetrafluoroethylene (PTFE) or a perfluoroalkylvinylether copolymer resin (PFA), Polyetheretherketone (PEE
K) and the like, and a polyimide resin is particularly preferable from the viewpoints of strength, belt moldability, dimensional stability, and flexibility.

The material for forming the rotating shaft for stretching the stretch belt of the present embodiment includes metals such as SUS, aluminum and iron, and fiber reinforced resin shafts reinforced with carbon fiber and the like. A material having sufficient strength to withstand the above. The rotating shaft is provided with a roughening treatment such as sandblasting or a coating of an elastic material such as silicon rubber or EPDM on the outer peripheral surface of the rotating shaft in order to reduce slippage with a tension belt stretched over the rotating shaft. It may be applied.

Further, the tension applied by the tension of the tension belt of the present embodiment by the tension shafts eliminates the slack of the surface between the tension shafts of the tension belts and drives the tension belts. In order to stabilize, the tension belt has a unit cross-sectional area of 0.5 N or more per 1 mm ^2, and in consideration of the strength, durability, durability of the tension shaft, and the limit of the load torque of the tension belt. Up to 50 per 1 mm ^{2 of} unit cross-sectional area
N is preferable, and 1 unit per 1 mm ²
A range from N to 10N is more preferable.

Further, the thickness of the base material of the stretch belt of the present embodiment is not less than 15 μm so as to maintain the strength of the stretch belt, and the stretch belt has flexibility, and the stretch belt is stretched. It is 300 μm or less, preferably 30 μm or more and 100 μm or less, and more preferably 50 μm or more and 75 μm or less so as to conform to the curvature of the frame.

As described above, the fixing belt 52 has the base material of the endless belt made of heat-resistant resin, the elastic layer, and the release layer. The elastic layer is made of a heat-resistant elastic material such as fluorine rubber, silicon rubber, or fluorosilicone rubber, and the release layer is made of a heat-resistant and high mold release material such as a fluororesin such as PFA, PTFE, or FEP, or a silicone resin. . The elastic layer and the release layer improve the image quality of the image fixed on the recording paper 41, improve the toner release performance, and prevent offset. In particular, when the fixing belt 52 is employed in a fixing device that handles a color image, the presence of the elastic layer in the fixing belt 52 improves the color development of the color toner, and improves the releasability of the recording paper 41 from the fixing roll 51. Improve. Note that the fixing belt 52 of the present embodiment is
Is formed by sequentially laminating an elastic layer and a release layer on a substrate of an endless belt made of a heat-resistant resin, but the fixing belt according to the present invention may be composed of only the substrate. Then, any one of the elastic layer and the release layer may be formed on the base material.

The elastic layer, the release layer, and the layer obtained by laminating both layers are applied by a coating method such as dip coating, spray coating, blade coating and the like. When the release layer is formed on the substrate, the release layer needs to have a thickness of 5 μm or more so that the three types of layers can be coated evenly. When a layer formed by laminating only the elastic layer or both layers is formed on the substrate, those layers need to have a layer thickness of 15 μm or more. On the other hand, if the layer thickness is too large, the coating process becomes many times, so that the production cost increases,
Since the heat conduction performance is reduced and the warm-up time and the energy consumption are increased, it is preferable that the above three types of layers have a maximum thickness of 500 μm. The layer thickness is preferably 10 μm or more and 100 μm or less when the layer formed on the base material is only a release layer, and the layer formed on the base material is separated from the elastic layer only or the elastic layer. When the mold layers are stacked, the thickness is 30 μm or more and 250 μm so that the effect of elasticity is not lost.
The following is preferred.

The material of the tension belt may contain carbon or metal filler for the purpose of preventing static electricity or the like, and may have a reduced electric resistance value, or a fibrous filler or reinforcing material may be added to increase the strength. May be. For example, a belt for transporting paper contains carbon or a metal filler and the like and has a reduced electric resistance value to about 10 ⁴ Ω in order to prevent abnormalities due to frictional charging of the belt at the time of paper transport and toner image transfer. Often used as a material. Intermediate transfer member 2
Is a recording sheet 4 of the toner image on the photoconductor 1 under various conditions.
In order to efficiently transfer the toner image to 1 without deteriorating the image quality of the toner image, a material whose electric resistance is controlled to a value in a semiconductive region of 10 ⁷ Ω to 10 ¹⁰ Ω is used as a material. .

Next, a method for manufacturing a polyimide belt, which is preferable as a base material of the stretched belt of the present embodiment, is used with reference to FIG.

FIG. 3 is a diagram showing a process of manufacturing a polyimide belt.

The process of manufacturing the polyimide belt proceeds in the following order: a raw material blending process, a mold preparation process, a film forming process, a secondary firing process, an annealing process, and a cut inspection process.

In the raw material blending step, polyamic acid is produced by polymerizing a polyimide varnish obtained by mixing a raw material monomer of diamine, an acid anhydride such as biphenyltetracarboxylic dianhydride (BPDA) and a solvent. A filler, a reinforcing agent, and the like are added to the polyamic acid as needed to form a heat-resistant resin solution d1 as a raw material.

In the mold preparation process, SUS, iron, aluminum,
A mold c1 is prepared, in which both the inner wall surface and the outer wall surface made of a heat-resistant material having stable dimensions and shape, such as fluororesin, are formed in a cylindrical shape. A process of applying a release agent is performed on the inner wall of the mold c1.

In the film forming step, the heat-resistant resin solution d1 produced in the raw material blending step is directly injected into the mold c1 prepared in the mold preparing step and sealed, and the mold c1 is roll-milled. While drying while rotating on the two axes c2 rotated in the same direction as seen in, for example, the endless belt d2 is heated at 120 ° C. to 130 ° C. by a heater.
Is centrifuged. The heat-resistant resin solution d1 containing the polyamic acid undergoes an imidization reaction by heating. However, if the imidization reaction is completely performed, it is difficult to remove the belt from the mold c1. Therefore, in general, the endless belt d2 is formed so that the imidation reaction is substantially prevented by adjusting the heating conditions. The film is formed and extracted from the inner wall of the cylindrical mold c1.

In the secondary firing step, a columnar mold c3 having a desired shape is inserted into the endless belt d2 extracted from the inner wall of the mold c1, and the mold is placed in an oven furnace, and the endless belt d2 is heated at 350 ° C. And sintering for imidization reaction. By this secondary firing step, the endless belt d2 shrinks and fits on the outer wall of the mold c3 to form an endless polyimide belt d3.

In the annealing step, the polyimide belt d
3 is annealed at 450 ° C. in an oven furnace. Further, in a cutting and inspection process, the polyimide belt d3 generated from the cylindrical mold c3 is removed and cut into a polyimide endless belt having a desired shape.

[0052]

The present invention will be described in more detail with reference to several examples and comparative examples of the present invention. The endless belts used in these examples and comparative examples were all manufactured by the above-described belt manufacturing method of the present embodiment. BPDA was used as an acid anhydride as one of the raw materials for producing this belt.

FIG. 4 is a view showing an endless belt of this embodiment.

Each of the belts manufactured in each embodiment described below has an inner diameter Dm of 68 mm as shown in FIG.
Was an endless belt b1 having a width W of 340 mm. Each of these belts was manufactured under conditions adjusted so that the film thickness would be 75 μm if a uniform film thickness was obtained on the entire belt surface. However, each of these belts
Films were formed using various molds different for each embodiment, and the center axis of the cylinder on the outer wall and the center axis of the cylinder on the inner wall of the mold were shifted, so that each of these belts was used. Did not always have a uniform value of 75 μm over the entire surface of each of these belts. Each of the belts manufactured in each of the comparative examples described later also has the above-described inner diameter Dm and width W.
, And each of these belts was also formed with a different mold for each comparative example.

[Example 1] A mold having a coaxiality of 70 µm, which is a distance between the center axis of the cylinder on the outer wall surface and the center axis of the cylinder on the inner wall surface, representing the deviation of the center axis. The belt of Example 1 was manufactured through the film forming process described above.

An aluminum pipe having an outer diameter slightly smaller than the inner diameter of the belt is inserted into the belt, and the width W of the belt shown in FIG. 4 on the belt is measured by an eddy current type film thickness measuring instrument (Permascope manufactured by FISHER). 17 places in the direction
A total of 30 designated at 18 locations in the circumferential direction F indicated by arrows
The film thickness was measured at six points.

As a result, the average film thickness at the 306 locations on the entire belt was 76 μm, the maximum film thickness was 82 μm, and the minimum film thickness was 69 μm.
m, the average value of the film thickness at 17 locations in the axial direction at each position in the circumferential direction is 78 μm at the maximum, and 74 μm at the minimum, and the variation is 4 μm (± 2.6% with respect to the average film thickness of the entire belt).
Met.

FIG. 5 is a diagram showing a situation in which unevenness on a stretched belt is measured.

In this figure, two stainless steel shafts s1 each having a diameter of 5 mm and having a weight of 5 kg, which are longer than the width of the belt b1, are provided inside an endless belt b1 as shown in FIG. Then, the two stainless steel shafts s1 are arranged in parallel and horizontally at intervals of 65 mm with a tension axis, and the belt b1 is moved by the gravity acting in the direction of the arrow a1 on the shaft s2 so that the belt b1 has a unit sectional area of 1 unit.
A three-axis stretching shaft device and a laser displacement meter e1 that are stretched at a tension of 1.9 N per mm ² (a tension of 50 N for the entire belt) are shown.

At a certain position in the circumferential direction of the belt b1 stretched over the two stainless steel shafts s1, the belt b1 has the same width and inner diameter as the belt b1 at each position in the stretch axis direction indicated by the arrow a2. The vertical displacement of the belt of Example 1 was measured while moving the laser displacement meter e1 in the direction of the tension axis.

FIG. 6 is a graph showing an example of the displacement of the belt surface.

The horizontal axis of this graph represents the tension axis direction measurement position, which is each position in the tension axis direction at a certain position in the circumferential direction of the belt of Example 1, in mm units. This position spans the entire width of the belt from 0 mm to 340 mm. The vertical axis indicates the displacement in the vertical direction at each of the above-described stretch axis direction measurement positions of the belt of Example 1 measured by the laser displacement meter e1 in FIG. The displacement in the vertical direction of the belt of Example 1 is 0 mm at the position of the end of the belt in the direction of the stretching axis of 0 mm, and gradually increases when the belt moves to a position near the intermediate portion of the belt in the direction of the stretching axis. And the arrow a at the 170 mm stretch axis direction measurement position.
As shown by 6, the maximum displacement was 0.6 mm. The displacement gently decreases and approaches 0 mm when moving from the position showing the highest displacement to the position 340 mm at the other end of the belt. In this belt, no large wavy irregularities were generated on the belt surface between the tension shafts at any position in the circumferential direction of the belt.

FIG. 7 is a diagram showing a recording paper transport device.

FIG. 7A shows two belts b1 shown in FIG.
Go through the shafts s3, and those shafts s3
The belt b1 is stretched by using these shafts as a stretching shaft for rotating the shafts while keeping the shafts parallel and horizontal, and the rotation of the shafts s3 drives the belt b1 in the direction of the arrow a3 to record on the belt b1. Loading and transporting paper 2
2 shows a recording paper transport device of a shaft.

FIG. 7B shows three belts b1 shown in FIG.
Through the shafts s4
Are kept parallel and horizontal, and the other one is kept below and parallel to the two above, and the belts b1 are stretched using the shafts as rotating stretch shafts, and the shafts s4 are stretched. The belt b1 is driven in the direction of arrow a4 by the rotation of, and the recording paper is placed on the belt b1 and transported.
2 shows a recording paper transport device of a shaft.

The belt of the embodiment 1 is shown in FIG.
The unit recording area of the belt is 1 mm ²
When the belt was stretched with a tension of 2.7 N per unit (tensile tension of 70 N for the entire belt), no noticeable wavy irregularities were generated on the belt surface between the stretching shafts at any position in the circumferential direction of the belt. Even when the paper was passed, neither fluttering of the paper nor scattering of toner on the recording paper due to the fluttering occurred.

Example 2 Next, the belt of Example 2 was manufactured through a film forming process using a cylindrical mold having a coaxiality of 88 μm between the outer wall surface and the inner wall surface. Example 1
As a result, the average film thickness at the 306 locations on the entire belt was 74 μm, the maximum film thickness was 81 μm, and the minimum film thickness was 68 μm.
m, the average value of the film thickness at 17 locations in the axial direction at each position in the circumferential direction is 76 μm at the maximum, 71.5 μm at the minimum, and the variation is 4.5 μm (+2.7 with respect to the average film thickness of the entire belt).
%, -3.4%).

[0068] The belt, the tension shaft device of a three-axis shown in FIG. 5, in Example 1 and similarly the belt unit cross-sectional area 1 mm ² per 1.9 N / mm ² tension (tension throughout the belt 50 N) In this case, when the belt was stretched, the same displacement as shown in FIG. 6 was exhibited, and no large wavy irregularities were generated on the belt surface between the stretching shafts at any position in the circumferential direction of the belt.

Further, the fluororubber solution was applied to the outer surface of the belt of Example 2 three times and air-dried, and then vulcanized at 230 ° C. for 4 hours to laminate a total of 180 μm fluororubber layers.
Again, this fluorine rubber laminated endless belt was
The recording sheet conveyance apparatus for three axes (B), the was stretched in a unit cross-sectional area 1 mm ² per 1.9 N / mm ² of the tension of the belt (tension throughout the belt 50 N), the circumference of the belt No large wavy irregularities occurred on the belt surface between the tension shafts at any position in the direction. This belt is used as a fixing belt 52 of a fixing device 5 of a roll-belt fixing system shown in FIG.
Used as

The aluminum hollow roll 51a of the fixing device 5 used in the second embodiment has an outer diameter of 62 mm and an inner diameter of 55 mm.
mm and a length of 330 mm, and the elastic layer 51
b is a layer made of liquid silicon rubber having a thickness of 1.5 mm and a material hardness of 33 °, and the heat-release oil-resistant layer 51c is obtained by applying a fluororubber to the surface of the elastic layer 51b to a thickness of 30 μm. there were. Fixing belt 52 used in Embodiment 2
The diameter of the two support rolls 54 and 55 that stretch the
m, and the diameter of one pressure roll 53 was 23 mm.

Here, in the fixing device 5 used in the second embodiment, the fixing belt 52 is stretched around the second support roll 55 and the pressure roll 53 with a tension of 98 N as a whole belt, and the pressure roll 53 is not shown. The coil spring was pressed toward the center of the fixing roll with a force of 350 N, and the pressing pad 56 was similarly pressed against the fixing roll with a force of 600 N.
As a result, the nip width became 23 mm.

The rotation speed of the fixing roll 51 is set to 20
0 mm / sec, the surface temperature of the fixing roll 51 is set to 150 ° C.
As a result, when 10,000 sheets of recording paper (J paper manufactured by Fuji Xerox Co., Ltd.) on which an unfixed toner image adhered were passed, the fixed image fixed by the fixing device 5 did not shift, and the recording was performed. Neither paper flapping nor toner scattering due to the flapping occurred, nor did the belt meander / skew.

[Other Embodiments] In addition to the cylindrical molds used in Embodiments 1 and 2, each of the seven embodiments was subjected to a film forming process using seven different cylindrical molds. Each belt was manufactured.

FIG. 8 shows the coaxiality of the outer wall surface and the inner wall surface of each of the plurality of cylindrical molds and the variation in the film thickness of each belt manufactured through the film forming process by each of the cylindrical molds. It is a graph which shows a relationship.

The horizontal axis of this graph represents the degree of coaxiality between the outer wall surface and the inner wall surface of each of the plurality of cylindrical molds in μm units, and the vertical axis represents the manufacturing process through the film forming process using each of the cylindrical molds. The variation of the average value of the film thickness measured at each point in the direction of the stretching axis at each position in the circumferential direction of the endless belt is expressed as a percentage of the film thickness.

Each of the seven black circles in the range p1 of this graph corresponds to the seven embodiments described herein. Note that the white circle p3 indicating the measurement result of the above-described variation in Example 1 is shown in this graph.
_ <B> 1 and a white circle p <b> 3 </ b> _ <b> 2 indicating the measurement results of the above-described variation in Example 2. As can be seen from this graph, when the concentricity of the cylindrical mold is 40 μm, the variation in the film thickness of the belt is 3%, and the concentricity is 12%.
When the belt thickness was increased to 0 μm, the above-mentioned variation in the film thickness of the belt also increased almost in proportion to the coaxiality and reached 9%.

Each of the belts of these seven embodiments was stretched on a two-axis recording paper transport device shown in FIG. 7A in the same manner as in the first embodiment. No noticeable wavy irregularities are generated on the belt surface between the tension shafts at any position in the circumferential direction of each belt. Even when the recording paper is passed, the recording paper flutters and on the recording paper due to the flutter No toner scattering occurred.

Further, a fluorine rubber layer was laminated on each of the belts of these seven examples in the same manner as in Example 2. These endless belts on which the fluororubbers were laminated were stretched on the triaxial recording paper transporting device shown in FIG. 7B in the same manner as in Example 2, and these stretched belts were stretched.
In each of the belts of the two examples, no large wavy irregularities occurred on the belt surface between the tension shafts at any position in the circumferential direction of each of the belts.

Each of these belts on which the fluororubber was laminated was used as the fixing belt 52 of the fixing device 5 of the roll-belt fixing system shown in FIG.
By using the fixing device 5 using these fixing belts 52, 100 sheets of recording paper (J paper manufactured by Fuji Xerox Co., Ltd.) having an unfixed toner image adhered to the surface thereof, as in the second embodiment.
When 00 sheets were passed, no deviation of the fixed image occurred, no fluttering of the recording paper and no toner scattering due to the fluttering occurred, and no meandering / skew of the belt occurred. Comparative Example 1 The belt of Comparative Example 1 was manufactured through a film forming process using a cylindrical mold having a coaxiality of 190 μm between the outer wall surface and the inner wall surface. As a result of measuring the film thickness of the belt of Comparative Example 1 in the same manner as in Example 1, the average film thickness of 306 locations on the entire belt surface was 7
4 μm, the maximum thickness is 88 μm, the minimum thickness is 65 μm,
The average value of the film thickness at 17 locations in the axial direction at each position in the circumferential direction is 80 μm at the maximum, 69 μm at the minimum, and the variation is 11 μm.
m (+ 8.1%, -6.8 with respect to the average film thickness of the entire belt)
%)Met.

When this belt was stretched on the three-axis stretching shaft device shown in FIG. 5 in the same manner as in the first embodiment, the belt surface between the stretching shafts was extended over about 2/3 in the circumferential direction as shown in FIG. Large wavy irregularities as shown in FIG. The waving of the belt surface was measured using a laser displacement meter shown in FIG.

FIG. 9 is a graph showing an example of the displacement of the belt surface.

The horizontal axis of this graph is the same as the horizontal axis of the graph of FIG. The vertical axis of the graph of FIG. 9 is the same as the vertical axis of the graph of FIG. 6 except for the scale.

The vertical displacement of the belt of Comparative Example 1 was 0 mm at the 10 mm and 330 mm stretch axis measurement positions near each end of the belt in the stretch axis direction shown in FIG. 50mm in the direction of the tension axis of the belt
It takes a large value having six local maximum points between the positions 280 mm and 280 mm. This displacement is equal to 10 in the tension axis direction of the belt.
The maximum displacement 1.35 mm as shown by the arrow a9_1 at the measurement position in the tension axis direction of 1 mm, and the unevenness of the waving, which is the difference between the adjacent maximum value and the minimum value of this displacement, is shown by the arrow a9_2. Shows 0.75 mm.

When this belt was stretched on a biaxial recording paper transport device shown in FIG. 7A in the same manner as in the first embodiment, large wavy irregularities were formed on the belt surface between the stretching shafts. When the recording paper was passed through the recording paper transport device, paper passing failure due to fluttering of the paper and scattering of toner on the paper occurred. Comparative Example 2 A belt of Comparative Example 2 was manufactured through a film forming process using a cylindrical mold having an outer wall surface and an inner wall surface having a coaxiality of 175 μm. As a result of measuring the film thickness of the belt of Comparative Example 2 in the same manner as in Example 1, the average film thickness of 306 locations on the entire belt surface was 7
5.5 μm, maximum thickness 89 μm, minimum thickness 65 μm
The average value of the film thickness at 17 locations in the axial direction at each position in the circumferential direction is 81 μm at the maximum, 69.5 μm at the minimum, and the variation is 11.5 μm (+7.3 with respect to the average film thickness of the entire belt).
%, -7.9%).

When this belt was stretched on a three-axis stretching shaft device shown in FIG.
For / 5, large wavy irregularities were generated on the belt surface between the tension shafts. When the undulation was measured using a laser displacement meter in the same manner as in Example 1, the same data as the belt of Comparative Example 1 was obtained, and the amount of unevenness of the undulation was 0.
It turned out to be 77 mm.

This belt was used under the same conditions as in Example 2 as shown in FIG.
Was used as the fixing belt 52 of the fixing device 5 shown in FIG. When 10,000 sheets of recording paper (J paper manufactured by Fuji Xerox Co., Ltd.) with an unfixed toner image adhered to the surface of the fixing device 5 were passed, the fixing belt 52 was wavy, and the area of contact with the support roll was increased. , The meandering / bias of the fixing belt 52 occurs, and the fixed image fixed by the fixing device 5 is displaced. The ratio of recording paper passing through the fixing device 5 is one in several. The toner fluttered and the toner scattered on the recording paper due to the flutter. [Other Comparative Examples] Three comparative example belts were manufactured through a film forming process using three different cylindrical dies other than the cylindrical dies used in Comparative Examples 1 and 2, respectively.

Each of the three black circles in the range p2 in the graph of FIG. 9 corresponds to the measurement result of the three comparative examples. The graph also shows a white circle p4_1 indicating the measurement result of the variation in Comparative Example 1 and a white circle p4_2 indicating the measurement result of the variation in Comparative Example 2.

As can be seen from this graph, when the concentricity of the cylindrical mold is 150 μm, the above-mentioned variation in the film thickness of the belt is 14%, and when the concentricity increases to 200 μm, the variation in the film thickness of the belt also decreases. It increases almost in proportion to the coaxiality and reaches 17%.

Each of these three comparative belts was stretched on a biaxial recording paper transport device shown in FIG. 7A in the same manner as in the first embodiment. However, large wavy irregularities were generated on the belt surface between the tension shafts, and when the recording paper was passed, poor paper passing due to fluttering of the paper and scattering of toner on the paper occurred.

Further, a fluorine rubber layer was laminated on each of these three comparative examples in the same manner as in Example 2. Under the same conditions as in Example 2, each of the belts on which these fluoro rubbers were laminated was used as the fixing belt 5 of the fixing device 5 shown in FIG.
Used as 2. When 10,000 sheets of recording paper (J paper manufactured by Fuji Xerox Co., Ltd.) having an unfixed toner image adhered to the fixing device 5 using each of these belts were passed, the belts of these three comparative examples were used. In the fixing device 5 using any one of the belts, as in Comparative Example 2, since the fixing belt 52 is wavy and the contact area with the support roll is reduced, meandering / skew of the fixing belt 52 occurs. The fixed image fixed by the fixing device 5 is displaced, and the recording paper passed through the fixing device 5 flutters at a rate of one out of several sheets, and the toner scatters on the recording paper due to the flutter. .

From the above Examples and Comparative Examples, the base portion of the stretched belt according to the present embodiment is such that the average thickness in the width direction intersecting with the above-described transporting direction is equal to the average thickness of the entire stretched belt in the transporting direction. It is understood that when the variation condition that the variation is less than ± 5% with respect to the average thickness of the entire stretch belt, no noticeable wavy irregularities are generated in the stretch belt.

A solid line q1 in the graph of FIG. 9 guides seven black circles in a range p1 representing the seven embodiments and three black circles in a range p2 representing the three comparative examples. The solid line q1 is a straight line indicating the above-mentioned variation of 3% at the coaxiality of 40 μm and the above-mentioned variation of 17% at the coaxiality of 200 μm. When the coaxiality is 120 μm, the above-mentioned variation shown by the solid line q1 is 1
0%.

For this reason, the tension belt of the present embodiment having a variation of ± 5% or less with respect to the average film thickness of the entire belt surface during the above-mentioned film forming process when manufacturing the tension belt is required. It can be seen that a cylindrical mold having a coaxiality of 120 μm or less between the wall surface and the inner wall surface was used.

[0094]

As described above, according to the present invention,
Conveying belt for smooth transport of the transported object while maintaining a gentle surface, preventing waving when being stretched on two or more axes. Wavy is prevented when being stretched on two or more axes. An intermediate transfer member that provides a good transfer without maintaining the smooth surface and preventing the toner of the toner image carried on the surface from scattering and causing a shift in the carried toner image. A fixing device that has a fixing belt with a smooth surface that is prevented from waving and that does not cause the toner on the unfixed toner image on the recording paper to scatter and that the image on the recording paper does not deviate, thereby performing a good fixing operation. And a belt manufacturing method for manufacturing a belt having a smooth surface that is prevented from waving when stretched around two or more shafts.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus according to an exemplary embodiment to which a conveying belt, an intermediate transfer member, and a fixing device of the present invention are applied.

FIG. 2 is a schematic configuration diagram of a fixing device according to the exemplary embodiment.

FIG. 3 is a diagram illustrating a process of manufacturing a polyimide belt.

FIG. 4 is a view showing an endless belt of the present embodiment.

FIG. 5 is a diagram showing a method for measuring unevenness on a stretched belt.

FIG. 6 is a diagram illustrating an example of a displacement of a belt surface.

FIG. 7 is a diagram illustrating a recording sheet transport device.

FIG. 8 shows the relationship between the coaxiality of the outer wall surface and the inner wall surface of each of the plurality of cylindrical molds and the variation in the film thickness of each belt manufactured through the film forming process by each of the cylindrical molds. It is a graph.

FIG. 9 is a graph showing an example of a displacement of a belt surface.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Intermediate transfer body 3 Bias roll 4 Tray 5 Fixing device 6 Developing part 21, 23, 24 Support roll 22 Backup roll 25 Conductive roll 26 Electrode roll 41 Recording paper 42 Feed roll 43 Transport path 51 Fixing roll 51a Hollow roll 51b Elastic body layer 51c Heat release oil resistant layer 53 Pressure roll 54 First support roll 55 Second support roll 56 Pressure pad 57 Cleaning means 58 Release agent uniform application means

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 15/16 G03G 15/16 15/20 102 15/20 102 F term (Reference) 2H032 AA05 BA09 2H033 AA08 AA09 AA15 BA08 BA12 BA16 BA43 BA49 BB01 BB28 BB39 3F049 BA01 BA14 BB12 LA02 LA05 LA07 LB03

Claims (10)

[Claims] 1. An endless transport belt which is stretched around a plurality of shafts and circulates in a predetermined transport direction, and which transports the transported material on a transported material, comprising: A transport belt, comprising a material, wherein a variation in an average thickness of the substrate in a width direction crossing the transport direction in the transport direction is ± 5% or less of an average thickness of the entire surface of the substrate. 2. The conveyor belt according to claim 1, wherein the plurality of shafts are stretched at a tension of 0.5 N or more and 50 N or less per unit cross-sectional area of 1 mm ^2.
The conveyor belt as described. 3. The transport belt according to claim 1, wherein the transport belt is formed using a polyimide resin as a material. 4. A recording medium having two rotating members rotating while contacting each other, and fixing the toner image on the recording material at a position where the two rotating members contact each other while moving the recording material to which the toner image is attached. In the fixing device, at least one of the two rotating members includes a fixing belt having a base material in the form of a resin endless belt that is stretched around a plurality of shafts and circulated and moved in a predetermined conveyance direction. And a variation in an average thickness of the substrate in a width direction intersecting the transport direction in the transport direction is ± 5% or less of an average thickness of the entire surface of the substrate. 5. The fixing belt according to claim 4, wherein the fixing belt is stretched around the plurality of shafts with a tension of 0.5 N or more and 50 N or less per unit cross-sectional area of 1 mm ^2.
The fixing device as described in the above. 6. The fixing belt according to claim 1, wherein at least one of an elastic layer having elasticity and a release layer for improving the releasability of the toner image is provided on the surface of the base material, or the elastic layer and the elastic layer. 5. The method according to claim 4, wherein two layers including the release layer covering the base material are formed, and a total thickness of the layers formed on the base material is 5 μm or more and 500 μm or less. Fixing device. 7. The fixing device according to claim 4, wherein the base material is formed using a polyimide resin as a material. 8. A toner image is transferred to a predetermined secondary transfer position by receiving a toner image on a surface thereof and is circulated and moved in a predetermined transport direction while being stretched around a plurality of shafts. In the intermediate transfer body in the form of a resin endless belt for transferring the toner image to a recording material, the average thickness in the width direction intersecting the conveyance direction varies in the conveyance direction with respect to the average thickness of the entire surface of the intermediate transfer body. 5%
An intermediate transfer member characterized by the following. 9. The intermediate transfer member according to claim 8, wherein the intermediate transfer member is formed using a polyimide resin as a material. 10. A mold in which both an inner wall surface and an outer wall surface are formed in a cylindrical shape, and a distance between a central axis of the inner wall surface cylinder and a central axis of the outer wall surface cylinder is 120 μm or less, is provided. A method of manufacturing a belt, wherein a resin solution is put into a mold, and the mold is rotated around a cylindrical center of an outer wall surface as a center of rotation to produce an endless resin belt.