JP2005128444A - Toner carrying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner carrying device stably carrying recovered toner removed from a photoreceptor surface at a high carry speed, even in a temperature environment which is near its melting point or even when some aggregate of toner occurs by eliminating sticking to a toner carrying surface. <P>SOLUTION: The toner carrying device carries recovered toner to a developing unit. A toner carrying coil is provided inside the toner carrying part and the surface of the toner carrying part 20 that is the toner carrying surface is formed by fluorinated carbon resin. In this case, laminated material of Mylar(R) 22 and fluorinated carbon resin film 23 adhered to each other by a double-sided tape is stuck to the surface of base material 21 through the Mylar(R) 22. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a toner conveying device provided in an electrophotographic image forming apparatus, and more specifically, in a toner conveying device including a toner conveying portion (toner conveying path) and a conveying coil accommodated therein. The present invention relates to the surface structure of the toner conveying portion.

In the printing technology related to electrophotographic image forming apparatuses (copiers, printers, facsimiles, and the like), energy saving, space saving, and high image quality have become a major trend.
First, as one of the above-mentioned technologies for energy saving, there is a technique for suppressing power consumption by lowering the melting point of toner and reducing the amount of heat necessary for heat fixing. Second, in order to reduce the installation space, it is indispensable to reduce the size of the machine, the layout space of the entire machine is narrowed, and a sufficient gap (margin) is provided between the units arranged in the image forming apparatus. ) Is required to achieve the function. Third, in order to improve the image quality, finer expression is realized by reducing the toner particle size.

  Here, problems in the cleaning unit (cleaning device) when achieving the above-mentioned energy saving, space saving, and high image quality will be described. This cleaning unit is an apparatus for removing and collecting the toner remaining on the surface of the photoreceptor after the toner image (development image) is transferred to the transfer paper in the electrophotographic image forming process.

  In the above space saving technology, the position of the fixing unit tends to approach the cleaning unit in order to promote downsizing. This is to reduce the overall layout by reducing the distance to the fixing unit as a process after the transfer of the toner image onto the transfer paper as much as possible. This indicates that the distance between the collected toner conveyance path in the cleaning unit and the fixing unit which is the largest heat source in the image forming apparatus is also shortened. As a result, in the image forming apparatus that has been downsized, the cleaning unit has a layout closer to the fixing unit, which is a large heat source, compared to the previous one, and therefore the temperature around the cleaning unit is 55. It has been confirmed that the temperature environment is less than ℃.

  One of the measures for realizing an appropriate environmental design is a technique for reducing the power consumption of the entire machine. For this purpose, it is effective to reduce the amount of heat for fixing that uses the most electric power. For this purpose, it is desirable to use a toner having a low softening point so that fixing can be performed at a low fixing temperature. Accordingly, the present inventor has made an image forming apparatus using a toner having a softening point (about 60 ° C.) lower than that of a conventional machine.

  However, as described above, the temperature environment around the cleaning unit having the collected toner conveyance path has been recognized as a temperature rise of slightly less than 55 ° C., and there is little margin for collected toner conveyance. Toner transport. As a problem that occurs in transport under such a condition with no margin, since the softening point of the toner represents the central value of the softening point distribution of the toner, it has a low softening point among the variations. For example, the toner is softened at the ambient temperature. For this reason, in the prototype, the softened toner adheres to the surface of the collected toner conveyance path, and the adhered toner grows. This eventually causes a major conveyance failure and causes a trouble that damages the toner conveyance mechanism.

Next, as an effective method for improving the image quality, it is possible to reduce the particle size of the toner so that the details can be expressed.
Conventionally, as a toner conveying device of an image forming apparatus, a toner conveying coil (configured by winding a long member having an appropriate cross-section in a spiral shape around a rotating shaft) is used. Then, since it becomes difficult to carry by the toner carrying coil, it is necessary to examine the cross-sectional shape of the coil body (described later).

By the way, the following patent documents 1-4 are mentioned as a prior art relevant to this invention.
The invention disclosed in Patent Document 1 relates to a cleaning device that constitutes an electrophotographic image forming apparatus, and the object and configuration thereof are as follows.
(1) Purpose: To provide a cleaning device capable of preventing toner accumulation at an edge portion of a cleaning blade.
(2) Configuration: Means for periodically changing the pressure contact force of the cleaning blade against the image carrier so as not to cause toner accumulation at the edge portion is in contact with the rotationally driven eccentric blade pressure roller. And a roller that is driven to rotate.

The contents of the invention disclosed in Patent Document 2 are as follows.
(1) Purpose: To prevent an increase in the concentration of the additive added to the toner over time, and to prevent the occurrence of abnormal images such as a decrease in black solid density and missing fine lines.
(2) The surface of the developing roller in the developing device for supplying one-component toner to the electrostatic latent image formed on the photosensitive member is coated with a fluorine-based or silicone-based resin, and water on the surface of the coated developing roller is coated. The contact angle with respect to the horizontal surface sample when the water dropped onto the horizontal surface sample of the developing roller is in a state of being kept in shape by surface tension, the additive in the toner It prevents adhesion to the surface of the developing roller via water molecules.

The contents of the invention disclosed in Patent Document 3 are as follows.
(1) Purpose: No charge is accumulated on the surface of the toner carrier (development roller, development belt, etc.). As a result, no afterimage is generated, and a sufficient charge amount is imparted to the toner. To provide a toner carrier having high environmental resistance suitable for conveying an amount of toner and, in addition, obtaining a stable high quality image.
(2) Configuration: In a toner carrier for making the toner supplied to the surface a uniform thin layer by a toner layer thickness regulating member, and using this toner for developing an electrostatic latent image, the surface is made of nitrile rubber and fluororesin. It is formed by the mixture of these.

Further, Patent Document 4 discloses an invention having the following contents.
(1) Purpose: To provide an image forming apparatus capable of stably flying visualized particles to form a high-quality image for a long period of time.
(2) A recording medium for forming an image by attaching toner, a recording medium conveying roller, a fixing roller for fixing the toner to the recording medium, a control electrode for controlling toner charged in accordance with image information by electrification control, and charged A plate electrode for adhering the toner on the recording medium, a toner conveying belt for placing and conveying the toner, roller-shaped first and second supporting means for winding and supporting the toner conveying belt, a toner layer thickness regulating member, This image forming apparatus is constituted by a toner supply roller or the like. In this case, the use of the first support means having a surface formed of a fluororesin has the effect that the movement of the toner conveying belt becomes smoother, wear is reduced, and the vibration is suppressed. .

  However, in the electrophotographic image forming apparatus, there is no technique that has studied and solved the problem of toner fixation on the toner transport surface that forms a transport path for transporting the toner removed from the surface of the photoreceptor.

JP-A-6-130863 JP-A-8-44192 JP-A-8-44195 JP-A-9-131916

  The present invention has been made in view of the above circumstances of the prior art, and an object of the present invention is to provide a temperature environment near the softening point of the recovered toner removed from the surface of the photoreceptor by the cleaning unit in an electrophotographic image forming apparatus. In addition, even if some agglomerates between toners are generated, a toner conveying device capable of stably conveying at a high conveying speed without sticking to the conveying surface is provided. It is to easily realize energy saving, space saving, and high image quality in the image forming apparatus of the type.

  The present invention relates to an electrophotographic image forming apparatus, wherein the toner removed from the surface of the photosensitive drum is transported to a predetermined portion by a toner transport coil provided in the toner transport unit. The surface, that is, the contact surface with the toner being conveyed is formed of a fluororesin.

According to a first aspect of the present invention, there is provided a toner conveying device that is disposed in the image forming apparatus and conveys the toner removed from the surface of the photosensitive member to a predetermined portion.
A toner conveying coil is provided in the toner conveying portion, and the surface of the toner conveying portion is formed of a fluororesin.

  According to a second aspect of the present invention, in the toner conveying device according to the first aspect, the toner conveying portion is a bowl-shaped toner storage portion having a substantially semicircular cross section constituting the cleaning unit.

  According to a third aspect of the present invention, the toner conveying portion is a toner conveying tube that conveys the toner conveyed by a toner conveying coil provided in the bowl-shaped toner storage portion further toward the developing unit. The toner conveying device according to claim 1.

  According to a fourth aspect of the invention, the toner conveying device is provided in an image forming apparatus that uses toner having a softening point of 80 ° C. or lower and an average particle size of 8 μm or lower. The toner conveying device according to any one of the above.

  The invention according to claim 5 is characterized in that the surface of the toner conveying portion is formed by sticking a fluororesin film having a thickness of 0.5 mm or less to the surface of the base material. The toner conveying device according to claim 1.

  According to a sixth aspect of the present invention, the fluororesin film is attached to the surface of a mylar (thickness is, for example, 0.7 mm or less) formed in the same shape as the surface shape of the base material constituting the toner conveying portion with a double-sided tape. 6. The surface of the toner conveying portion is formed by preparing a laminate formed by sticking and sticking the laminate to the surface of the base material via a mylar. It is a toner conveyance apparatus of description.

  According to a seventh aspect of the present invention, the coil main body of the toner conveying coil has a substantially rectangular cross-sectional shape and a corner roundness of 1 mm or less (R ≦ 1), and fluorine forming the toner conveying portion surface. It is characterized in that there is no bulge on the surface of the toner conveying part (which causes disturbance of the flatness of the surface of the toner conveying part) due to bubbles having a diameter of 1 mm or more between the resin film and the base material on the lower layer side. The toner conveying device according to claim 1.

  According to an eighth aspect of the present invention, there is provided an image forming apparatus comprising the toner conveying device according to any one of the first to seventh aspects.

  According to the toner conveying device according to any one of claims 1 to 3, the recovered toner removed from the surface of the photoreceptor can be conveyed even in a temperature environment near the softening point, or even when agglomerates of the toners are somewhat generated. It can be stably conveyed at a high conveyance speed without sticking to the surface, and energy saving, space saving, and high image quality of an electrophotographic image forming apparatus are facilitated.

  In a conventional toner conveying device, when the image forming apparatus using toner having a softening point of 80 ° C. or lower and an average particle diameter of 8 μm or smaller is saved in space, the toner aggregates easily occur on the conveying surface. Although there is a problem that the toner is easily fixed, such a problem is accurately solved in the toner conveying device of the present invention (claim 4).

  In the toner conveying device according to the fifth aspect, the fluororesin film having a thickness of 0.5 mm or less is adhered to the surface of the base material to form the toner conveying portion surface. The toner can be held firmly, and the toner can be stably conveyed at a high conveyance speed over a long period of time.

  In the toner conveying device according to claim 6, since the surface of the toner conveying portion is formed by adhering a predetermined laminate, the fluororesin film that forms the surface of the toner conveying portion and the mylar on the lower layer side thereof Therefore, there is no bulge on the surface of the toner conveying portion due to the bubbles remaining between them, and a highly smooth toner conveying portion surface can be formed (see claim 7). In this case, it is preferable that the laminate is similarly attached to the surface of the base material with a double-sided tape, and the laminate can be accurately and firmly attached to the curved surface of the base material. It is possible to easily form a very high toner conveying portion surface.

  In the toner conveying device according to the seventh aspect, since the cross-sectional shape of the coil body is substantially rectangular, the toner conveying ability is greatly improved as compared with a conveying coil composed of a coil body having a circular cross section. In addition, since there is no bulge on the surface of the toner conveying portion due to bubbles having a diameter of 1 mm or more between the fluororesin film forming the surface of the toner conveying portion and the base material on the lower layer side, the coil body having the above-mentioned substantially rectangular cross section Even if is used, a high toner conveying function can be exhibited over the entire life of the machine without damaging the surface of the toner conveying portion.

  An image forming apparatus according to an eighth aspect of the present invention can provide an image forming apparatus including the toner conveying device that exhibits the effect of any one of the first to seventh aspects.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a main part structure of an electrophotographic image forming apparatus (copier) equipped with a toner conveying device of the present invention, and is a schematic diagram of a photosensitive drum and each unit disposed around the photosensitive drum. The structure is shown.

  First, an outline of the structure and operation of the entire copying machine will be described. The photosensitive drum 10 serving as an image carrier rotates in the direction of the arrow, and the surface is uniformly charged by the first charging unit 2, and a laser beam corresponding to the image information is generated in the axial direction of the photosensitive drum 10 by an exposure unit (not shown). And is sub-scanned by the rotation of the photosensitive drum 10. Thereby, an electrostatic latent image corresponding to the image information is formed on the surface of the photosensitive drum 10. This electrostatic latent image is developed by the developing unit 3 to become a toner image. The toner image rotates and moves to the transfer unit 11 via the second charging unit 4 and is transferred to the transfer paper P here. The transfer paper P is separated from the photosensitive drum 10 by the separation claw 5, and is fixed by a fixing unit (not shown), thereby completing the printing.

  On the other hand, the toner remaining on the surface of the photosensitive drum 10 after the transfer is removed and recovered by the cleaning blade 9 of the cleaning unit 12 (hereinafter, the recovered toner is referred to as recovered toner). Thereafter, the charge remaining on the surface of the photosensitive drum 10 is neutralized by the neutralizing light from the neutralizing lamp 1, and the surface of the photosensitive drum 10 is prepared for the next image formation.

  The cleaning unit 12 includes a cleaning blade 9 that presses against the surface of the photosensitive drum 10, a rotating shaft that is parallel to the rotating shaft of the photosensitive drum 10, and a brush tip that is in sliding contact with the surface of the photosensitive drum 10. A cylindrical cleaning brush 8 (which rotates while being in contact with the surface of the photosensitive drum), a toner conveying coil 7 for conveying the collected toner collected by the cleaning brush 8 to the developing unit 3, and the like. It is prepared for.

  Further, as a mechanism for maintaining the toner density of the developer in the developing unit 3 within a predetermined range, light reflection is used at a position close to the surface of the photosensitive drum 10 and facing the surface. A toner image density sensor 6 is provided.

The structure and action of the cleaning unit 12 and the structure for transporting the toner collected by the cleaning unit to the developing unit 3 will be described more specifically.
In the transfer process, the toner image on the surface of the photosensitive drum is not 100% transferred to the transfer paper P, and a part of the toner image remains on the surface of the photosensitive drum. The residual toner is scraped off by a rubber cleaning blade 9 that rubs against the surface of the photosensitive drum, and falls onto the toner transport coil 7 via the cleaning brush 8. The toner conveying coil 7 is a screw-type rotating body that is rotatably supported on the front and rear side plates of the housing 12a constituting the cleaning unit 12, and is rotated by a driving mechanism (not shown) to collect the collected toner to the photosensitive member. The drum 10 is moved to the near side or the far side of the drum 10, and is returned to the developing unit 3 through an unillustrated opening through a screw conveyor type recovery toner conveying device (not shown). The returned toner is supplied to the developing unit 3 in an appropriate amount and reused for image formation.

  2 to 4 relate to the toner conveying device according to the present invention, FIG. 2 is a schematic plan view showing the main part structure, FIG. 3 is a schematic sectional view of the collected toner storage unit, that is, the toner conveying unit, and FIG. FIG. 3 is a schematic perspective view showing a part of the toner conveying portion. The toner transport unit 20 is a part of the bottom of the housing 12 a constituting the cleaning unit 12 and has a substantially arc-shaped cross section. The toner transport coil 7 is parallel to the rotation axis of the photosensitive drum 10. And is configured to convey the collected toner to the developing unit 3. The surface of the toner transport unit 20 corresponds to the toner transport surface of the toner transport device according to the present invention.

  A driven gear 31 is attached to one end of the toner conveying coil 7 in the axial direction, the driven gear meshes with a drive gear 32 constituting a drive mechanism (not shown), and the coil body 7a and the rotary shaft 7b are integrated. The toner is conveyed by rotating. In addition, the toner conveying device (not shown) is connected to the end of the toner conveying portion 20 opposite to the driven gear 31, and the collected toner is collected in the direction of arrow A in FIG. It is conveyed toward the developing unit 3. The toner conveying device includes a tube body and a screw conveyor type conveying member that is rotatably inserted into the tube body, and the inner peripheral surface of the tube body also includes the toner conveying device according to the present invention. This corresponds to the toner transport surface of claim 3.

  Note that a lot of patent documents disclose toner recycling type image forming apparatuses provided with a toner conveying device for conveying toner collected from the surface of the photosensitive drum to a developing unit by a screw conveyor type conveying mechanism. For example, FIG. 2 of Japanese Patent Application Laid-Open No. 9-138579 shows a plan view of the toner conveying device, which is configured to replenish the collected toner from the collected toner replenishing port to the toner hopper of the developing unit.

  The feature (Claim 2) of the toner conveying device according to the present invention is that the surface of the toner conveying portion 20, that is, the toner conveying surface is formed of a fluororesin in FIGS. Specifically, the surface of the toner conveying portion is formed by sticking a fluororesin film having a thickness of 0.5 mm or less to the surface of the base material 21 made of, for example, hard plastic. In this case, a fluororesin film 23 is adhered to the surface of Mylar 22 (thickness is, for example, 0.7 mm or less) formed in the same shape as the surface shape of the base material 21 constituting the toner transport unit 20 with a double-sided tape. It is preferable to form the surface of the toner conveying section by sticking the laminate to the surface of the base material via Mylar 22 (the structure and effect of claim 6). See description).

In consideration of recycling of the components of the toner conveying device, it is desirable that the adhesive paste can be peeled off from the adhesive surface. From this point of view, it is optimal to select a double-sided tape as the adhesive member. In addition, the fluororesin is very soft, and if it has a thickness of about 0.1 mm, it is very difficult to attach to a curved surface such as a toner conveying surface, and has the same shape as the conveying surface as described above. It is effective to apply a double-sided tape to Mylar once and then apply a fluororesin film on this double-sided tape. In addition, by using a member with a very high degree of freedom of bending, such as Mylar, as the base material to which the fluororesin film is to be applied, the Mylar is once flattened even in a curved shape. It is possible to form a fluororesin toner conveying surface by sticking a soft and non-waist fluororesin film thereon.
In addition, as a method for coating the surface of the substrate with a fluororesin, an appropriate one can be selected and applied from other known methods such as a method of applying a paint containing a fluororesin. The method is more desirable.

  As the Mylar material, a material made of a resin such as polyethylene terephthalate, polyethylene, polyimide, or polyamide can be used. As the fluororesin, polyfluorinated ethylene, polytetrafluoroethylene, polyvinyl fluoride or the like (Teflon (registered trademark) VALFLON (registered trademark) or the like) can be used.

  In the above-mentioned background art section, it has been explained that when a toner particle having a small particle size is conveyed by a toner conveying coil, it is necessary to examine the cross-sectional shape of the coil body. For example, in the toner conveying coil 50 as shown in FIG. 6 using a member having a circular cross section as the long member, the amount of toner passing through increases and the staying time of the collected toner becomes longer. The toner conveying coil 50 is configured by winding a linear member having a circular cross section around a rotation shaft 51 to constitute a coil main body 52. Reference numeral 53 denotes a driven gear for rotating the toner conveying coil 50.

  To solve the above problem, a toner carrying coil 40 having a coil body 42 formed by winding a belt-like member having a substantially rectangular cross section around the rotation shaft 41 as shown in FIG. It has been confirmed that it is effective to increase Here, FIG. 5A is a front view showing the main part of the transfer coil, FIG. 5B is a perspective view showing the shape of the coil body, and FIG. 5C is a sectional view taken along line BB in FIG.

  As described above, in order to transport toner having a small particle size, it is necessary to use a coil having a high transport capability, and as shown in FIG. It is effective to use. However, in an experiment using a prototype of the toner conveying device conducted by the present inventor, the edge of the coil body (corner having a square cross section) is scratched almost circularly on the plane of the toner conveying surface made of fluororesin. (Not shown) may occur.

As a result of examination,
(1) This scratch is caused by the fluororesin film being broken into a circle, and the cause is that air bubbles having a diameter of 1 mm or more existed between the fluororesin film and the Mylar surface.
(2) In the method of sticking a fluororesin film using a double-sided tape, the above-mentioned bubbles do not occur, whereas in the method of applying an adhesive on the substrate surface and sticking the fluororesin film on this, This bubble is likely to be generated,
(3) Even if the bubbles are present, they are difficult to be generated in the toner conveying coil having a coil body having a circular cross section as shown in FIG. 6, whereas the rectangular cross section shown in FIG. It was found that the toner transport coil provided with the coil body is likely to be generated.

  As a method for preventing air bubbles having a diameter of 1 mm or more from being generated under the fluororesin film, a method of spraying a fluororesin-containing coating onto the substrate surface can be considered. In this method, the fluororesin is applied to the substrate surface. In some cases, the fixing force is small and the intended purpose of the present invention cannot be sufficiently achieved. On the other hand, it was confirmed that by using the film member as the fluororesin according to the present invention, the life of the toner conveying surface is sufficiently long even when the fluororesin surface is polished with toner or the like.

  The toner conveying device according to the illustrated embodiment receives and conveys the recovered toner that is removed from the surface of the photosensitive drum by the cleaning blade and discharged from the cleaning brush, and the toner conveying surface is a cleaning unit. In the present invention, the fluororesin film is formed on the substantially semicircular bottom surface of the toner storage section (on the bowl-shaped bottom surface of the substantially semicircular cross section). Item 3) is also effective.

  The toner conveying device according to this embodiment is configured by a toner conveying coil rotatably inserted in a circular tube, that is, a toner conveying coil and a tubular toner conveying surface surrounding the outer periphery of the toner conveying coil. 2 and 3 is connected to the toner conveying device shown in FIGS. 2 and 3, and conveys the collected toner toward the developing unit 3, and the tubular toner conveying surface is formed on the inner peripheral surface of the tubular body. It is formed by coating with a fluororesin film.

  The present invention is not limited to an electrophotographic image forming apparatus that uses toner as a developer, and is an apparatus that conveys fine powder whose fluidity changes due to heat, particularly those having a diameter of 10 μm or less, and those having a low softening point. It can be applied widely and effectively.

FIG. 2 is a cross-sectional view of a main part structure of an electrophotographic image forming apparatus (copier) equipped with the toner conveying device of the present invention, and shows a schematic structure of a photosensitive drum and each unit disposed around the photosensitive drum. Is. FIG. 3 is a schematic plan view showing a main part structure of the toner conveying device. FIG. 2 is a schematic cross-sectional view of a toner transport unit that constitutes the toner transport device. FIG. 3 is a schematic perspective view illustrating a part of a toner conveyance unit constituting the toner conveyance device. The present invention relates to a toner conveying coil formed by winding a belt-like member having a substantially rectangular cross section around a rotation axis, wherein (a) is a front view showing the main part of the conveying coil, and (b) is the shape of the coil body. The perspective view shown, (c) is the BB sectional drawing of (b). FIG. 6 is a perspective view of a toner conveying coil configured by winding a linear member having a circular cross section around a rotation axis.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Static elimination lamp 2 1st charging unit 3 Developing unit 4 2nd charging unit 5 Separation claw 6 Density sensor 7 Toner conveyance coil 7a Coil body 7b Rotating shaft 8 Cleaning brush 9 Cleaning blade 10 Photosensitive drum 11 Transfer unit 12 Cleaning unit 12a Case Body 20 Toner transport unit 21 Base material 22 Mylar 23 Fluororesin film 31 Drive gear 32 Drive gear 41 Rotating shaft 42 Coil body 40 Toner transport coil 50 Toner transport coil 51 Rotating shaft 52 Coil body 53 Drive gear P Transfer paper

Claims (8)

In a toner conveying device that is arranged in an image forming apparatus and conveys toner removed from the surface of a photoconductor to a predetermined part,
A toner conveying device comprising: a toner conveying coil in a toner conveying portion; and a surface of the toner conveying portion formed of a fluororesin.   The toner conveying device according to claim 1, wherein the toner conveying unit is a bowl-shaped toner storage unit having a substantially semicircular cross section that constitutes a cleaning unit.   The toner transport unit according to claim 1, wherein the toner transport unit is a toner transport tube that transports the toner transported by a toner transport coil provided in the bowl-shaped toner storage unit toward the developing unit. apparatus.   4. The toner transport according to claim 1, wherein the toner transport device is provided in an image forming apparatus using a toner having a softening point of 80 ° C. or lower and an average particle diameter of 8 μm or lower. apparatus.   The toner conveying device according to claim 1, wherein the surface of the toner conveying portion is formed by adhering a fluororesin film having a thickness of 0.5 mm or less to the surface of the substrate.   A laminate is prepared by sticking the fluororesin film with a double-sided tape on the surface of a mylar molded in the same shape as the surface shape of the base material constituting the toner conveying portion, and the laminate is passed through the mylar. The toner conveying device according to claim 5, wherein the surface of the toner conveying portion is formed by sticking to the surface of the base material.   The coil main body of the toner conveying coil has a substantially rectangular cross-section and a corner roundness of 1 mm or less, and between the fluororesin film forming the surface of the toner conveying portion and the base material on the lower layer side. The toner conveying device according to claim 1, wherein there is no bulge on the surface of the toner conveying portion due to bubbles having a diameter of 1 mm or more. An image forming apparatus comprising the toner conveying device according to claim 1.

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