JPH10153890A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an excellent image on recording material by an image forming means by attracting corrugated recording material closely on a recording material carrier carrying and feeding the recording material. SOLUTION: This image forming device possesses the recording material carrier 8 carrying and feeding the recording material and an image forming means forming an image on the recording material carried by the recording material carrier. In this case, a flexible upper guide member 38 pressing the recording material carried from the upper side of the recording material carrier to the recording material carrier and an electrifier for attraction 30 positioned on the lower side of the recording material carrier in accordance with the upper guide member and electrostatically attracting the recording material to the recording material carrier are provided, so that the recording material is attracted to the recording material carrier closely.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a printer, a facsimile, a copying machine, and the like, and more particularly to a multiple image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, there has been known an image forming apparatus which forms an image using a plurality of photosensitive drums.

As shown in FIG. 6, this type of image forming apparatus comprises four photosensitive drums 1a, 1b, 1c which form toner images of respective colors of yellow, magenta, cyan and black and which are arranged in parallel with each other. , 1d, and a transfer belt 8 arranged below the photosensitive drums 1a to 1d so as to extend longitudinally therethrough.

Around primary photosensitive drums 1a to 1d, primary chargers 2a, 2b, 2c, 2d, developing units 3a,
3b, 3c, 3d, transfer chargers 4a, 4b, 4c, 4
d, and a cleaner (not shown), and LED devices 5a, 5b, 5c, 5d as exposure means are arranged above the photosensitive drums 1a to 1d.

The photosensitive drums 1a, 1b, 1c, and 1d are charged by respective primary chargers 2a to 2d, and the separated yellow, magenta, cyan, and black light images are LED devices 5a, 5b, 5c, and 5c. Exposure by 5d,
Photoconductor drums 1a, 1b, 1c, 1 such as electrophotographic photoconductors
d, yellow, magenta, cyan, and black latent images are formed, and the respective latent images are developed by the developing units 3a to 3d, and yellow, magenta, cyan, and black are formed on the photosensitive drums 1a, 1b, 1c, and 1d. The toner images of
Form.

On the other hand, transfer paper as a recording material is supplied from registration rollers 10a, 7a to 7c from sheet feeding units 7a to 7c having a sheet feeding cassette, a pickup roller, a conveying roller and the like.
The roller 10a is fed to the transfer belt 8 by the rollers 10a and 10b. Transfer paper is suction roller 1
The sheet is conveyed to the image transfer area while being held on the transfer belt 8 by the action of the suction unit such as 1. Here, the method of holding the transfer belt 8 on the transfer belt 8 may be mainly electrostatic attraction onto a transport medium made of a thin dielectric film or the like. Transfer belt 8
The transfer paper adsorbed on the photosensitive drums 1a, 1b, 1c, and 1d is sequentially conveyed by the rotation of the transfer belt 8 to the transfer units opposed to the respective photosensitive drums 1a, 1b, 1c, and 1d. A toner image is transferred onto the transfer paper in a superimposed manner by the operation of the transfer chargers 4a to 4d arranged in each transfer section, and a color image in which four color toner images of yellow, magenta, cyan, and black are superimposed on the transfer paper Is obtained.

The transfer paper on which the four color toner images have been transferred is separated from the transfer belt 8 at the rear end in the transport direction and is fixed by a fixing device 9.
The toner is then fixed by receiving heat and pressure, whereby the toners of the respective colors are dissolved and mixed to form a full-color print image fixed on the transfer paper, and then discharged outside the copying machine. The transfer of the photosensitive drums 1a, 1b,
1c and 1d clean the remaining toner after transfer by the respective cleaners and prepare for the next image formation.

Next, the structure of a general suction unit is shown in FIG.
This will be described in detail based on this. The transfer paper sent from the registration roller 10 reaches the suction roller pair 11. The lower suction roller 11a of the suction roller pair 11 is connected to the charger 4, and the upper suction roller 11b is grounded. Then, a high voltage is applied to the charger in synchronization with the timing at which the transfer paper enters the suction position, thereby generating charges on the transfer paper and the transport medium (transfer belt 8),
The transfer paper is electrostatically attracted to the transfer belt 8. Also,
As another method for adsorbing the transfer paper, as shown in FIG. 8, the photosensitive drums 1a to 1d grounded and the photosensitive drum 1
A method is also considered in which transfer blades 12a to 12d, which are located at positions opposite to a to 1d and are connected to the charger, simultaneously attract the transfer sheet and the transfer belt 8 and transfer the transfer sheet to the transfer sheet.

[0009]

In the conventional image forming apparatus as described above, transfer paper left in a high humidity environment,
The transfer paper that has passed through the fixing device once in the double-sided copy mode may be in a “wavy” state in which the transfer paper partially expands because the transfer paper itself absorbs a large amount of moisture.

In the configuration shown in FIG. 7 or FIG. 8, when the transfer paper in the "wavy" state enters the suction portion, the transfer paper in the "wavy" state is suctioned onto the transfer belt 8 while partially forming a gap. Will be done. As a result, "transfer missing" in which an image formed on the transfer paper is partially missing may occur.

As a countermeasure for the above-described transfer omission, as shown in FIG. 9, a mylar 13 for pressing the transfer paper against the transfer belt from above has been considered to be provided upstream of the suction section in the transfer paper transfer direction. Since the transfer paper is actually attracted to the transfer belt 8 at the downstream position in the paper transport direction of the mylar 13, the transfer paper is once extended by the mylar while the transfer paper is being transported from the mylar 13 to the suction unit. The transferred transfer paper returns to the original transfer paper in a wavy state, and is adsorbed in a state where there is a gap between the transfer belt 8 and the transfer paper, which may cause transfer omission.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an image forming apparatus which always maintains a good image quality in which transfer omission does not occur irrespective of transfer paper conditions and environmental conditions.

[0013]

According to a first aspect of the present invention, a recording material carrier for carrying and transporting a recording material is provided.
An image forming apparatus having image forming means for forming an image on a recording material carried on the recording material carrier, a flexible upper guide member for pressing the recording material against the recording material carrier from above, An adsorber for electrostatically adsorbing the recording material to the recording material carrier, which is located below the recording material carrier corresponding to the upper guide member, and which is upstream of the image forming means in the recording material transport direction; It is characterized by being provided in.

A second invention is characterized in that the upper guide member in the first invention has a width shorter than a width of a recording material having a maximum size on which an image is formed.

A third invention is characterized in that the entire width of the upper guide member and the attraction charger in the first invention is set to 50 to 200 mm.

According to a fourth aspect of the present invention, in the second or third aspect, both sides of the upper guide member and a predetermined range from the contact portion between the upper guide member and the recording material carrier to the upstream side in the transport direction are provided. A lower guide member for guiding the lower side of the recording material is provided above the transfer belt.

A fifth invention is characterized in that the lower guide member in the fourth invention is made of a flexible material.

A sixth invention is characterized in that a plurality of the upper guide members according to the second or third invention are provided, and the plurality of upper guide members are sequentially increased in width from the upstream one in the transport direction. .

According to a seventh aspect of the present invention, in the sixth aspect of the present invention, both sides of the plurality of upper guide members and a predetermined range from the contact portion between each upper guide member and the recording material carrier to the upstream side in the transport direction. In this case, a lower guide member for guiding the lower side of the recording material is provided above the transfer belt.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) An embodiment of the present invention will be specifically described with reference to FIG. Hereinafter, an electrophotographic method is used as an image forming method, and a color image output apparatus in which the present invention is considered to be particularly effective will be described. In this example, a digital color image reader section is provided above the image output section, and the printer section is provided below the image output section.

In the reader section, an original is placed on an original platen glass and exposed and scanned by an exposure lamp. The reflected light image from the original is condensed by a lens on a full-color sensor to obtain a color-separated image signal. This signal is subjected to various processes in a video processing unit via an amplifier circuit, and then sent to an image output unit.

The image output unit is configured as described below. The image output unit is roughly divided into an image forming unit 20
(Four stations a, b, c, and d are arranged side by side and have the same configuration. The symbols a to d are attached as suffixes of the respective symbols like the photosensitive drum 1a). It comprises a paper feed unit 7, a transfer / conveyance unit 8, a fixing unit 9, and a control unit (not shown). Further, this unit will be described in detail.

The image forming section 20 has the following configuration. Photoconductor drums 1a to 1d as image carriers
Primary chargers 2a to 2a facing the outer peripheral surface of
d, optical systems 5a to 5d, and developing devices 3a to 3d. In the primary chargers 2a to 2d, the photosensitive drum 1
A uniform amount of charge is applied to the surfaces a to 1d. Subsequently, an electrostatic latent image is formed on the photosensitive drums 1a to 1d by exposing the photosensitive drums 1a to 1d by, for example, an LED device modulated according to a recording image signal by the optical systems 5a to 5d.
Further, the developing devices 3a to 3d (in the present device, four color developing agents such as yellow, cyan, magenta, and black (hereinafter referred to as toners)
4a to 14d, which are brought close to the photosensitive drum of each station) to make the electrostatic latent image conspicuous. On the downstream side of the image transfer area T in the photosensitive drum rotation direction, cleaning is performed by removing toner remaining on the photosensitive drum without being transferred to the recording material by the cleaning devices 15a to 15d. With the process described above,
Image formation by each toner is performed sequentially.

The paper supply unit 7 includes a cassette 15 for storing recording paper P as a recording material, and a pickup roller 1 for feeding out recording paper one by one from the cassette.
6. Paper feed roller 23 for transporting the recording paper sent from the pickup roller to the registration roller
a and 23b, a paper feed guide 24, and a transport unit 25 for transporting the recording paper in accordance with the image forming timing of the image forming unit.
It has registration rollers 10a and 10b as second transport means for sending the recording paper to the transfer paper transport unit, which will be described later.

The transfer transport unit 25 as the first transport means will be described in detail. The unit 25 includes a plurality of rollers on which a recording paper holding sheet (for example, PET <polyethylene terephthalate> or PVdF
<Polyvinylidene fluoride> or the like is used). 27 is a sheet drive roller, 28 is a driven roller, and an image transfer plane is formed between these two rollers. More specifically, the distance between the sheet and the photosensitive drum is only slightly (about 1 mm). Reference numeral 29 denotes a tension roller for applying an appropriate tension to the sheet of the transfer belt 8.

An adsorption charger 30 is disposed at a position where the recording paper sent from the registration roller enters the transfer belt 8, and each photosensitive drum downstream of the charger in the recording paper transport direction faces the transfer belt. In the image transfer area, transfer charging blades 4a1 to 4d1 are arranged behind the holding sheet. The blade can be pressurized and separated from the photosensitive drum by a mechanism (not shown). At the time of pressurization, good image transfer is performed by lifting the sheet and pressing it against the drum with an appropriate pressure. Drive roller 27
A charging / discharging / charging unit 31 for separating and removing the recording paper is disposed slightly upstream of the charging / discharging / charging unit 32 for applying a uniform charge to the sheet surface, and a charging / discharging unit 32 for cleaning the recording paper holding surface of the sheet. A brush roller 33 and the like are provided.

The fixing unit 9 as a fixing unit includes a fixing roller 34 having a heat source such as a halogen heater therein.
a and a pressure roller 34b pressed against the roller (this roller may also be provided with a heat source), and an input guide 3 for guiding the recording paper to the nip portion of the roller pair.
5, an inner discharge recording paper roller 3 for further guiding the recording paper discharged from the roller pair to the outside of the apparatus.
6. It is composed of an externally discharged recording paper roller 37 and the like.

The control unit includes a control board, a motor drive board, and the like for controlling the operation of the mechanism in each unit.

Next, description will be made in accordance with the operation of the apparatus.

When an image forming operation start signal is issued, first, recording paper P is fed out of the cassette 15 by the pickup roller 16 one by one. Then, the recording paper is guided between the paper feed guides 24 by the paper feed rollers 23a and 23b, and is conveyed to the registration rollers 10a and 10b. At that time, the registration roller is stopped, and the leading end of the recording paper strikes the nip portion and is skewed.
Thereafter, the registration roller starts rotating at the timing when the image forming unit starts forming an image. The rotation timing is set so that the recording paper and the toner image on the photosensitive drum exactly coincide in the image transfer area.

When the recording paper enters and comes into contact with the holding sheet moving by the driving roller of the transfer belt 8, the recording paper is electrostatically attracted by Coulomb force generated on the sheet by the action of the attraction charger. The transfer belt rotates in synchronization with the photosensitive drum, and the recording paper is transported to the first image transfer area Ta while being held thereon. In this case, a high voltage is applied to the transfer charging blade 4a1 pressurized at the start of the sequence in accordance with the passage timing of the recording paper. Then, the toner image formed on the photosensitive drum by the above-described process is transferred onto the surface of the recording paper, and then the recording paper is further conveyed to the next image transfer area. Here, the image formation is performed with a delay corresponding to the time required for the recording paper to be conveyed between the stations, and the next toner image is transferred with the registration on the previous image. Hereinafter, the same process is repeated, and eventually, the toner images of four colors are multiplex-transferred.

When the operation is completed, the adsorbing force between the recording sheet and the holding sheet is reduced by the action of the charge removing device in the separating section, and the recording sheet is separated from the holding sheet by the curvature of the driving roller that follows.

The recording paper separated from the transfer belt is accurately guided by the entrance guide 35 to the fixing roller nip. The toner image is fixed on the recording paper surface by the heat of the roller 34a and the pressure of the nip. Thereafter, the recording paper is conveyed by inner and outer discharge paper rollers 36 and 37,
The recording paper is discharged outside the machine. The transfer blade is depressurized and the sequence ends with the sheet separated from the drum (to protect it by minimizing external forces on the drum).

The features of the present embodiment reside in the following upper guide member 38 and suction charger 30. This will be described with reference to FIG. The phenomenon of transfer omission is caused by the relatively large recording paper size (A3 size: 29).
7 × 420). The upper guide member 38 has, for example, a length in the width direction (a direction perpendicular to the recording material conveyance direction and also in the main scanning direction at the time of image formation) of the maximum size of the recording paper (the normal maximum size is A3, the width direction length) Length is shorter than 297mm (50mm-200m)
m), and is made into a film or a thin plate by a flexible mylar (trade name) or the like arranged so as to be pressed onto the transfer belt 8. The upper guide member 38
By urging the central portion of the conveyed recording paper to the transfer belt 8 with an appropriate elastic force, the gap between the central portion of the recording paper and the transfer belt 8 is eliminated, and at the same time, the recording paper is moved to a position facing the upper guide member 38. First, only the central portion of the recording sheet is electrostatically adsorbed to the transfer belt 8 by a certain adsorbing charger 30. At this point, portions other than the center of the recording paper (both ends) are not attracted to the transfer belt 8, and there is no gap between the center of the recording paper and the transfer belt 8.

Next, the recording paper adsorbed only at the central portion is further conveyed and passes through the photosensitive drum 1a. The photosensitive drum 1a is grounded. A transfer blade 4a is provided at a position facing the photosensitive drum 1a, and is connected to a charger for transferring toner onto recording paper. According to this configuration, the recording paper functions to transfer when the recording paper passes through the photosensitive drum 1a, but also functions to attract the recording paper to the transfer belt 8 at the same time. Therefore, the recording paper that has passed through the upper guide member 38 and has been suctioned only at the central portion first can be extended in the width direction of the recording paper because both ends thereof are not yet suctioned and are in a free state. Next, by passing through the photosensitive drum 1a, the entire area (entire width) of the recording paper can be electrostatically attracted without any gap on the transfer belt 8.

That is, if the entire area of the recording paper is attracted to the transfer belt 8 at the same time by using a roller or the like, the recording paper in the wavy state is simultaneously adsorbed to the transfer belt 8, so that the slack due to the waving of the recording paper is eliminated. Is lost, and the waving is not completely removed, resulting in transfer omission.

Thus, the central portion of the recording paper that has reached the transfer belt 8 is pressed onto the transfer belt 8 by the upper guide member 38 and is attracted to the destination, thereby forming a gap between the transfer paper 8 and the central portion of the recording paper. After removing the slack of the recording paper to both ends that have not been adsorbed, the photosensitive drum 1
The entire area of the recording paper is sucked by a. As a result, the gap with the transfer belt 8 can be removed in the entire area of the recording paper. Further, it is more cost effective than the suction roller 11 of FIG. 7 which has been conventionally used as a measure against transfer omission.

(Second Embodiment) In the configuration shown in FIG. 1, the transfer charger 4a
To 4d, charged by the charger 30, etc.
Unnecessary charges are removed by 2 or the like. Then, in the next round, the transfer belt 8 from which charge has been removed as described above is newly charged by the charger 30 and the like. However, actually, even on the transfer belt 8 after the charge elimination is performed, the charge is not completely eliminated, but is slightly charged. The recording paper before reaching the transfer belt 8 is also usually slightly charged.

The present embodiment solves such a problem. FIG. 3 shows a diagram that best illustrates the features of the second embodiment.

In the first embodiment, the central portion of the corrugated recording paper is transferred to the transfer belt 8 by the upper guide member 38 and the charger 30.
A non-sucking area is formed on both sides of the sheet, and the area is ideally uncharged. For this reason, the recording paper conveyed is transferred to the transfer belt 8. Is electrostatically attracted to the transfer belt 8 with a slight attraction force only by contacting the uncharged area. In such a state, as in the first embodiment, even if the recording paper is pressed against the transfer belt 8 from above in the vicinity of the central portion of the recording paper and simultaneously adsorbed by the charger 30, the recording paper in the area of the upper guide member 38 can be obtained. The gap between the transfer belt 8 and the transfer belt 8 is eliminated, but the vicinity of the non-sucking area on both sides (main scanning direction) of the recording sheet is also slightly absorbed. It cannot escape completely to both sides, and it occurs near both ends of the upper guide member 38.

Therefore, in this embodiment, the upper guide member 3
Lower guide members 39 for preventing the recording paper and the transfer belt 8 from contacting each other are provided in the non-sucking area portions on both sides of the position where the recording paper 8 contacts the recording paper. The width of the lower guide member may be the same as or smaller than the width of the non-sucking regions on both sides. The lower guide member includes an upper guide member and a transfer belt 8.
The length is a predetermined distance upstream from the contact portion with the recording material conveyance direction, but may extend downstream from the contact portion as shown in the figure. With this configuration, the recording paper does not come into contact with the transfer belt 8 and suction in this area is prevented. The lower guide member 39 is grounded to prevent charging. When the lower guide member 39 is arranged at a position where no gap is formed between the lower guide member 39 and the transfer belt 8, the bending of the recording paper pressed by the upper guide member is suppressed. Can be. In addition, the lower guide 39 is
Is arranged, it is desirable that the material of the lower guide 39 be a flexible or flexible material (eg, Mylar (trade name) or the like) so as not to damage the transfer belt 8. In addition, it is preferable in terms of manufacturing that the lower guide member is formed as a substantially U-shaped integral unit as shown in the figure without separately manufacturing the lower guide portions on both sides.

With the above configuration, by completely preventing the recording paper from being attracted to the non-sucking areas on both sides, the gap between the recording paper and the transfer belt formed by the wrinkled state of the recording paper can be reduced. The recording paper can be electrostatically adsorbed onto the transfer belt 8 without any gap since the recording paper can be effectively released by the adsorption area. Therefore, transfer omission can be prevented.

(Third Embodiment) FIG. 4 shows a diagram that best illustrates the features of the third embodiment.

In this embodiment, in order to further enhance the effect of preventing transfer omission of the first embodiment, the width Y is larger than the width X of the upper guide member 38 between the upper guide member 38 and the photosensitive drum 1a. A second upper guide member 40 which is wider and shorter than the photosensitive drum 1a and a second suction charger 41 having the same width as the second upper guide member 40 are provided. In this way, the gap between the recording sheet and the transfer belt 38 is gradually released to both sides (main scanning direction), so that the recording sheet is attracted to the transfer belt 8. Thereby, transfer omission can be prevented. In this embodiment, the recording paper is adsorbed by the upper guide member and the charger twice in the upstream side of the photosensitive drum 1a, but the recording is performed by providing the upper guide member and the charger for adsorption twice or more. The paper may be electrostatically attracted to the transfer belt.

(Fourth Embodiment) FIG. 5 is a diagram best showing the features of the fourth embodiment.

In the present embodiment, the upper guide member 38 and the second upper guide member 40 are in contact with the recording paper, as in the second embodiment, in order to further enhance the effect of the transfer omission of the fourth embodiment. Recording paper and transfer belt 8
The lower guide 42 is provided so as not to come into contact. In this case, the shape of the lower guide 39 is such that the upper guide member 38 and the second
The upper guide member 38 and the second upper guide member 4 so that the upper guide member 40 can come into contact with the conveyed recording paper.
The shape is cut out by a width of 0. This prevents the recording paper and the transfer belt from adsorbing on both sides of each upper guide member, and for the same reason as described in the second embodiment,
Transfer omission can be more effectively prevented.

The above embodiment has been described with reference to an example of a four-color copying machine. However, the present invention is not limited to this, and a recording material is adsorbed and carried on a recording material carrier to form an image on the recording material. Needless to say, the present invention can be applied to an image forming apparatus that performs the following operations.

[0048]

As described above, according to the present invention,
A flexible upper guide member for pressing the recording material onto the recording material carrier from above the recording material carrier; and a recording material carrier positioned below the recording material carrier corresponding to the upper guide member. The space between the wavy recording material and the transfer belt is moved to both sides by adsorbing only the central part of the recording material on the upstream side of the image forming means by providing an adsorption charger for electrostatically adsorbing the recording material. Thus, the recording material can be adsorbed to the recording material carrier without any gap. Also, by providing the lower guide member on the transfer belt near both sides of the upper guide member, when the upper guide member and the charger adsorb only the central portion of the recording material earlier, the recording material in a wavy state near both sides thereof And the transfer belt can be prevented from adsorbing, the movement of the space between them can be ensured, the gap can be eliminated, and the recording material can be adsorbed favorably on the transfer belt.

[Brief description of the drawings]

FIG. 1 is a sectional view of an entire image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a main part according to the first embodiment of the present invention.

FIG. 3 is a perspective view of a main part according to a second embodiment of the present invention.

FIG. 4 is a perspective view of a main part according to a third embodiment of the present invention.

FIG. 5 is a perspective view of a main part according to a fourth embodiment of the present invention.

FIG. 6 is a cross-sectional view of a conventional image forming apparatus.

FIG. 7 is a perspective view showing an example of a conventional electrostatic attraction of a recording material onto a transfer belt.

FIG. 8 is a perspective view showing an example of conventional electrostatic attraction of a recording material onto a transfer belt.

FIG. 9 is a perspective view showing an example of a conventional electrostatic attraction of a recording material onto a transfer belt.

[Explanation of symbols]

1a to 1d photosensitive drums 2a to 2d primary chargers 3a to 3d developing devices 4a to 4d transfer chargers (blades) 5a to 5d LED devices 6a to 6d cleaners 7a to 7d feed units 8 Transfer belt 9 ... Fixing device 10a, 10b ... Regist roller 11 ... Suction roller 12a-12d ... Transfer blade 13 ... Mylar 14 ... Hopper 15 ... Cassette 30, 41 ... Suction charger 31 ... Separation and charge removal charger 32 ... Charger 38, 40 ... Upper guide member 39, 42 ... Lower guide member

Claims (7)

[Claims] A recording material carrier that carries and conveys the recording material;
An image forming apparatus comprising: an image forming unit that forms an image on a recording material carried by the recording material carrier; a flexible upper guide member that presses the recording material onto the recording material carrier from above; An adsorber for electrostatically adsorbing the recording material to the recording material carrier, which is located below the recording material carrier corresponding to the upper guide member, and which is upstream of the image forming means in the recording material transport direction; An image forming apparatus provided in the image forming apparatus. 2. The image forming apparatus according to claim 1, wherein the upper guide member has a width shorter than a width of a recording material having a maximum size on which an image is formed. 3. An image forming apparatus according to claim 1, wherein a total width of said upper guide member and said attraction charger is set to 50 to 200 mm. 4. A lower guide member for guiding a lower side of a recording material on both sides of the upper guide member and over a predetermined range from a contact portion between the upper guide member and the recording material carrier to an upstream side in the transport direction. The image forming apparatus according to claim 2, wherein the image forming apparatus is provided above the transfer belt. 5. The image forming apparatus according to claim 4, wherein said lower guide member is made of a flexible material. 6. The image forming apparatus according to claim 2, wherein a plurality of the upper guide members are provided, and the plurality of the upper guide members are sequentially increased in width from the upstream one in the transport direction. 7. The image forming apparatus according to claim 6, wherein
A lower guide member that guides the lower side of the recording material on both sides of the plurality of upper guide members and a predetermined range from the contact portion between each upper guide member and the recording material carrier to the upstream side in the transport direction is transferred. An image forming apparatus provided above a belt.