JP2000347534A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device making the coefficient of friction on the image carrier surface stabilized to the satisfying value. SOLUTION: This image forming device, is provided with developing means developing the latent image on the image carrier, transferring means transferring the toner image on transfer paper, a contact function member to the image carrier such as cleaning means adopting a contact blade as well as applying means applying a releasing agent holding the applying member 7 in directly contact with the above image carrier. Then, the above applying member 7 is a roller of a triple-layer structure consisting of a core bar 7a, an elastic layer 7b and the lubricant layer 7c, making the lubricant layer 7c into the structure capable of forming a wide nip held in contact with the image carrier in rotatably by the relative peripheral speed differential with regard to the image carrier held in contact with the image carrier.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as a copying machine, a facsimile, and a printer.
More particularly, the present invention relates to an apparatus provided with an application unit for applying a lubricant to the surface of an image carrier used in an electrostatic copying process of an image forming apparatus by directly contacting an application member.

[0002]

2. Description of the Related Art As a technique for applying a lubricant to the surface of an image carrier used in an electrophotographic copying process such as a copying machine, the following technique is known.

For example, Japanese Patent Application Laid-Open No. Sho 56-74283 discloses that
An "apparatus for applying a low coefficient of friction substance of an electrophotographic copying machine" of the present applicant is disclosed. In this application apparatus, a lubricant disposed downstream of a cleaning unit and supplying a cleaning effect to a photoreceptor surface is supplied. It has a sub-cleaning means.

Japanese Patent Application Laid-Open No. Sho 61-153684 discloses that
A cleaning device is disclosed which includes a supply means for supplying a lubricant to a non-image area on the surface of the photoconductor downstream of a cleaning blade extending beyond the image area to the vicinity of both ends of the photosensitive layer of the photoconductor and pressing against the surface. ing.

Japanese Patent Application Laid-Open No. Hei 10-260614 discloses that
An "image forming apparatus" of the present applicant is disclosed, and the image forming apparatus has a brush that contacts a surface of an image carrier,
And a member for applying a lubricant to the surface of the image carrier while being rotationally driven.

[0006]

However, in a conventional image forming apparatus having a functional member that comes into contact with a photoreceptor, such as a developing unit and a transfer unit, as well as a cleaning unit,
For example, in the apparatus described in JP-A-56-74283, the length of the lubricant in the axial direction of the photoconductor is substantially the same as the length of the photosensitive layer and is permanently provided. The balance between the application of the lubricant and the recovery by the developing unit and the transfer unit is lost in the portions other than the portions that are in contact with each other, and the supply outside the developing unit and the transfer unit is excessive, resulting in poor cleaning at both ends of the blade and toner scattering. This may cause abnormal images.

Further, in the apparatus described in JP-A-61-153684, since a lubricant is permanently provided downstream of the blade in a portion of the blade outside the image area where the blade contacts the photosensitive member, the supply becomes excessive. The cleaning failure occurs in the portion, and the scattering of the toner causes an abnormal image to be generated.

In the apparatus described in Japanese Patent Application Laid-Open No. 10-260614, since the lubricant is uniformly applied to the surface of the photoreceptor over substantially the entire area in the axial direction of the photoreceptor, both the developing means and the transfer means are in contact with each other. Except for the portion, the balance between the collection of the lubricant by the developing unit and the transfer unit and the application of the lubricant is lost, which causes the occurrence of an abnormal image as described above.

Therefore, the present invention solves the above-mentioned disadvantages and facilitates the transfer of the lubricant to the image carrier, so that the coating amount of the lubricant and the recovered amount are easily balanced. It is an object of the present invention to provide an image forming apparatus provided with:

[0010]

In order to achieve the above object, an image forming apparatus according to the present invention comprises a developing means for developing an electrostatic latent image formed on the image carrier, and a transfer paper for developing the developed image. The image carrier having at least one unit provided with a functional member that comes into contact with the rotating image carrier, such as a transfer unit that transfers the image to the image carrier, or a cleaning unit that abuts the blade on the surface of the image carrier after the transfer. An image forming apparatus provided with an application unit for applying a lubricant to the surface of the image carrier by directly contacting the application member with the image carrier; It is characterized by having an elastic layer between it and the agent.

The base portion of the coating member is a metal core having a cylindrical outer peripheral surface, and the elastic layer is provided on the outer peripheral surface of the metal core,
It is preferable that a lubricant layer is provided on the outer periphery of the elastic layer to form a triple-layer rotating roller.

Further, the coating member has a lubricant layer over the entire area in the outer circumferential direction, and the lubricant layer is brought into contact with the image carrier to form a nip, and a peripheral portion relative to the image carrier is formed. It is desirable to be able to rotate with a speed difference.

When the peripheral speed ratio when the coating member is at the same peripheral speed as the image carrier is 0.0, and when the peripheral speed ratio when the coating member is stopped is 1.0, the image bearing member has It is preferable that the rotation direction of the application member with respect to the body is the forward direction, and the peripheral speed ratio is 0.1 or more. Further, it is preferable that the rotation direction of the coating member with respect to the image carrier is the counter direction, and the peripheral speed ratio is 1.1 or more.

The pressing force of the coating member against the image bearing member can be any value between 10 N and 80 N as a pulling force per 0.03 m width of the paper sandwiched by the nip. Further, it is preferable that the lubricant is higher in the same charging series as the toner polarity.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an entire configuration around an image carrier of the image forming apparatus of the present embodiment. Around the photosensitive drum 1 as an image carrier rotated in the direction of the arrow, in addition to the charge removing lamp 2 and the charging roller 3, a developing unit having a developing roller 4, a transfer unit 5 having a transfer roller 5, and a cleaning blade Various units including a functional member that comes into contact with the drum surface, such as a cleaning unit having a unit 6, are disposed. Downstream of the cleaning means, there is provided an application means in which a lubricant supply roller 7 as an application member is brought into direct contact with the surface of the photosensitive drum 1. A series of image forming processes of this apparatus is an example of a negative-positive (N / P) type in which toner adheres to a place where electric potential is low. First, the operation of the entire machine will be described.

When the print button of the operation unit (not shown) is pressed and the operation is turned on, the discharging lamp 2, the charging roller 3,
A predetermined voltage or current is sequentially applied to the developing roller 4, the transfer roller 5, and the separation electrode 8 at a predetermined timing ゛. Almost at the same time, the photosensitive drum 1 and the charging roller 3
The transfer roller 5 of the transfer means, the development roller 4 of the development means, the left screw 9 and the right screw 10, the toner discharge screw 11 of the cleaning means, and the lubricant supply roller 7 rotate in predetermined directions, respectively. start.

The surface of the rotating photosensitive drum 1 is
The charge is removed by the charge removing lamp 2, and the lubricant is applied almost uniformly to the surface by the lubricant supply roller 7 rotating while being pressed against the drum surface with a predetermined pressing force. Then, after being uniformly negatively charged (−900 V) by the charging roller 3 rotating while being in contact with the photosensitive drum 1, predetermined image information is converted into an optical signal by scanning with a laser beam 4, and the surface of the drum is scanned. A latent image is formed (black solid potential is -150 V).

The electrostatic latent image is developed by a developing roller 4 which has been made into a magnetic brush shape by a developer containing toner charged and frictionally charged by being conveyed and agitated by two screws 9 and 10 in the developing means. The developing bias is set to -600 V), and the image is visualized as a toner image. Then, between the photosensitive drum 1 and the transfer roller 5, the transfer paper fed from a paper feed mechanism (not shown) is transferred to the registration roller 12 and the lower registration roller 1.
3, the toner image is supplied in synchronization with the leading end position of the toner image. The toner image formed on the photosensitive drum 1 is transferred (+10 μA is applied) to the fed transfer paper by contact of the transfer roller 5 and application of a transfer bias.

The transfer paper on which the toner image has been transferred is separated from the photosensitive drum 1 by the separation electrode 8 and sent to a fixing device (not shown), where the toner is fixed by heating and pressing, and then as a copy image. Emitted outside the machine. On the other hand, the toner remaining on the photosensitive drum 1 without being transferred by the transfer roller 5 is transferred to the cleaning unit by the rotation of the photosensitive drum 1, and is removed by the cleaning blade 6 abutting on the surface of the photosensitive drum 1 in the counter direction. The toner is then conveyed by the toner discharge screw 11.

FIG. 2 is a sectional view showing the overall structure of the lubricant supply roller 7. The lubricant supply roller 7 as a coating member according to the present invention is a rotating roller, and a foamed polyurethane 7b as an elastic layer is provided on an outer peripheral surface of a cylindrical or columnar core metal 7a serving as a base portion thereof. A layer of a lubricant 7c is provided on the outer peripheral portion of 7b, and is configured in a three-layer structure. As described above, according to the configuration in which the lubricant supply roller 7 that is in pressure contact with the photosensitive drum 1 has the elastic layer between the base portion and the surface lubricant 7c, a large pressing force is applied. Even without this, a nip having a width in the circumferential direction can be formed between the photosensitive drum 1 and the entire surface in the longitudinal direction.

As shown in the example of FIG. 1, the lubricant supply roller 7 is a pressing compression spring 14 as a biasing means so as to come into pressure contact with the photosensitive drum 1 with a predetermined pressing force.
Urged in the direction of the photosensitive drum 1. In this state, the foamed polyurethane 7b can be deformed by a weak urging force of the compression spring 14 or the like, and a nip can be formed at the contact portion of the lubricant supply roller 7. In this way, if a wide nip can be formed even with relatively weak pressure welding, the lubricant 7c
Transfer to the drum surface is easy. As described above, since the pressing force required for applying the lubricant 7c is the minimum, the lubricant 7c is applied.
Excessive supply of c can be suppressed and coating unevenness can be prevented. In this embodiment, the tensile force per 3 cm width of the paper sandwiched between the photosensitive drum 1 and the lubricant 7c is 10 N
The photosensitive drum 1 is pressed against the photosensitive drum 1 with a strength of about 80N.

In order to reduce the occurrence of streak-like application unevenness, the lubricant supply roller 7 can apply the lubricant 7c by a rotating cylindrical surface, and the lubricant supply roller 7 can be disposed between the lubricant supply roller 7 and the photosensitive drum 1. It is driven to rotate with an appropriate peripheral speed difference. The lubricant supply roller 7 rotates in a direction opposite to the photosensitive drum 1 (counter direction). Here, when the photosensitive drum 1 and the lubricant supply roller 7 have the same peripheral speed. When the peripheral speed ratio is set to “0.0” and the peripheral speed ratio when the lubricant supply roller 7 is stopped is set to “1.0”, the peripheral speed ratio is substantially “1.2”.
The setting is made so that Note that the peripheral speed difference required for reducing coating unevenness or the like may be a relative difference, so that if the rotation is in the counter direction as in the present embodiment, the lubricant supply roller 7 has a slow reverse rotation. The circumferential speed ratio is preferably 1.1 or more. If the rotation direction of the lubricant supply roller 7 is set to the forward direction, the circumferential speed ratio is slightly slower than that of the photosensitive drum 1 and is 0.1 or more. It is preferable to set the speed ratio. Regardless of the rotational direction, such a difference in peripheral speed allows the entire cylindrical surface of the lubricant supply roller 7 to be used uniformly, and stable application can be performed for a long period of time.

The lubricant 7c is a fluorine-based material such as polytetrafluoroethylene (PTFE). The lubricant 7c has a higher charging series than the polarity of the toner used for the photosensitive drum 1. That is, the lubricant 7 is applied to the toner which takes on “negative polarity” when charged and rubbed.
c is also of a negative charging series, which is charged to “minus” when rubbed, and is higher in the charging series. Therefore, even if the pressing force is small and the peripheral speed difference is small as described above, it is possible to easily transfer the photosensitive drum 1 to the charged photosensitive drum 1.

As shown in FIG. 1, a lubricant supply roller 7 is constantly pressed against the photosensitive drum 1 by a compression spring 14, and rotates in contact with the photosensitive drum 1 to make contact with the surface of the photosensitive drum 1. Due to the difference in the coefficient of friction with the surface of the lubricant supply roller 7, the lubricant 7c is almost uniformly transferred to the drum surface while being scraped off. The change in the coefficient of friction of the drum surface, that is, the change with time of the lubricant 7c applied on the photosensitive drum 1 can be explained as follows.

The lubricant 7c transferred onto the photosensitive drum 1
Passes between the charging roller 3 and the pressure contact,
At this time, a voltage of “negative polarity” (−
1600 V) is applied, the lubricant 7 c of the same charging series does not adhere to the charging roller 3. When the photosensitive drum 1 reaches the developing area, the potential on the surface of the photosensitive drum 1 becomes “−900”.
V "and the developing bias corresponding thereto is" -600
V, there is a potential difference of "300 V" during this period, and a part of the lubricant 7c on the photosensitive drum 1 is collected by the developing means. This recovered amount is about 35% of the amount of the lubricant 7c applied on the photosensitive drum 1.

Next, when reaching the transfer means, a constant current of "+10 μA" is applied to the transfer roller 5, and about 44% is collected. As a result of this collection, about 21% of the lubricant 7c remains on the photosensitive drum 1 and reaches the cleaning means. With the remaining amount of the lubricant 7c, the lubricant 7 on the photosensitive drum 1 is
Most of c is not scraped off and goes again to the application area of the lubricant 7c. Such a process is repeated, and the surface of the drum lowers to a coefficient of friction corresponding to the contact condition of the lubricant supply roller 7 for each rotation.

However, as described above, the lubricant 7c is recovered at the two locations of the developing means and the transfer means, and the recovery by the developing means among them occurs only during the initial operation. That is, when the lubricant 7c is mixed in the developer, the lubricant 7c mixed in the developer by the rubbing by the magnetic brush is again applied to the photosensitive drum 1.
After a certain period of time, the amount of the lubricant 7c in the developer gradually increases, and the amount of recovery and the amount of re-application become the same, so that the recovery by the developing means is practically impossible. Therefore, when the friction coefficient is stabilized, the collection is performed only by the transfer unit, and the application amount and the collection amount in the transfer unit are the same.

Therefore, the coefficient of friction becomes stable after a certain period of time, so that the photosensitive drum 1
After the amount of the lubricant 7c remaining on the upper surface increases sequentially, the applied amount and the recovered amount must be the same. For this purpose, "when the coating amount is constant and the collection amount increases to catch up with the coating amount", "when the coating amount decreases and the collection amount increases", or "when the collection amount is constant and the coating amount 3 is considered. Since the actual recovery amount decreases over time due to re-application by the developing means, "when the coating amount is constant and the recovery amount increases to catch up with the coating amount" or "when the coating amount decreases and the recovery amount increases And the coefficient of friction becomes stable when "the collection amount is constant and the application amount decreases".

The lubricant supply roller 7 according to the present invention is capable of performing favorable application in accordance with a reduction in the friction coefficient of the drum surface in a state where the lubricant nip is formed by pressing the photosensitive drum 1 lightly to form a wide nip. The coefficient of friction of the surface of the photosensitive drum 1 is maintained at a constant value when the application and the recovery of the lubricant 7c are balanced after a certain period of time. Also,
As described above, in a stable state after a lapse of a certain time, the amount of development and transfer to the transfer unit is constant, and a desired friction coefficient can be obtained by setting appropriate contact conditions.
For example, when it is desired to increase the friction coefficient, the pressing force of the lubricant supply roller 7 may be reduced, or the peripheral speed ratio with the photosensitive drum 1 may be reduced to reduce the application amount. When it is desired to lower the friction coefficient, the pressing force may be increased, or the peripheral speed ratio may be increased to increase the application amount.

The coefficient of friction of the surface of the photosensitive drum 1 is
The photoconductor drum 1 and the blade 6 must be abraded and stabilized in a region where other side effects do not occur. Hereinafter, setting of the contact condition of the lubricant supply roller 7 for obtaining a desired friction coefficient will be described.

FIG. 3 is a view for explaining an apparatus for measuring the friction coefficient of the drum surface, and FIG. 4 is a view for explaining a method for measuring the paper pulling force of the lubricant supply roller 7. FIG. 5 is a diagram showing the relationship between the number of passed sheets and the friction coefficient of the drum for each of the different settings (5N to 100N) of the paper pulling force.

As shown in FIG. 3, the coefficient of friction of the surface of the photosensitive drum 1 can be measured by a method generally called an Euler belt type. For example, the measuring device includes a drum support 1 for holding the photosensitive drum 1 on a base 15.
6 and force gauge base 1 on which force gauge 17 is placed
8 are fixed. A belt 19 that is in surface contact with the drum surface is connected to the force gauge 18, a weight 20 is hung at the end of the belt 19, and the resistance between the drum surface and the belt 19 is read. Find μ. In this example, the friction coefficient μ when a weight 20 of 100 g was hung was determined by the following equation. μ = ln ((F / 100) / (π / 2))

In the above-mentioned image forming apparatus, it is desirable that the friction coefficient μ not causing wear of the drum or the like and causing other side effects be in the range of μ = 0.2 to 0.3.
When the friction coefficient μ is larger than 0.2 to 0.3, for example, when μ = 0.4, wear occurs on both the photosensitive drum 1 and the cleaning blade 6. Conversely, when it is small, for example, when μ = 0.1, such wear does not occur, but side effects such as image deletion occur.

On the other hand, as shown in FIG. 4, the pressing force of the lubricant supply roller 7, that is, the pressure contact force between the photosensitive drum 1 and the lubricant supply roller 7, sandwiches the paper 21 having a width of 3 cm therebetween. The paper 21 was pulled through the tension gauge 22 and measured as a pulling force of the paper 21. The pulling force of the paper 21 indicates the pressing force of the lubricant supply roller 7, and the number of rotations matches the pressing force.

The diagram of FIG. 5 is an experimental result showing the change in the friction coefficient of the drum surface with the number of sheets passed when different pulling forces are set. In this experimental example,
The peripheral speed ratio between the lubricant supply roller 7 and the photosensitive drum 1 is "1.
2 ". As shown in FIG. 5, the friction coefficient μ stabilizes at a constant value when the number of sheets exceeds a predetermined number. In order to obtain a good value of 0.2 to 0.3 of the friction coefficient μ in this, 10N to 80N / 0.03 m
It has been found that under the conditions of the present embodiment, an appropriate value is maintained without abrasion of the drum and image flow.

In this experimental result, even if the pulling force of the paper 21 is 5 N / 0.03 m, it is possible to reduce the friction coefficient μ to 0.2 to 0.3 by increasing the peripheral speed ratio. is there. However, in such a case, the peripheral speed ratio must be set to a large value of "4 to 5".
In order to make the photosensitive drum linear velocity (200 m
m / sec), calculated from the lubricant supply roller 7 (φ14 mm), the necessary rotation speed is “1091 rpm to 136 rpm”.
4 rpm ". If such high-speed rotation is required, other problems such as abrasion of the bearing and noise will occur.

On the other hand, at 100 N / 0.03 m, it is only necessary to lower the peripheral speed ratio. In this case, however, in order to obtain a good friction coefficient μ = 0.2 to 0.3, the peripheral speed ratio should be reduced. The speed ratio needs to be "0.02-0.05". In this case, the number of rotations of the lubricant supply roller 7 ranges from “5 rpm to 13 rpm”.
m ", which is considerably slower than the rotation speed of the other parts.
In this case, a deceleration mechanism for that purpose is required, resulting in an increase in cost. In consideration of the above, the peripheral speed ratio of the present embodiment is fixed to the above-mentioned “1.2”, and the contact condition of the lubricant supply roller 7 with which a good friction coefficient μ is obtained is set. And the value of the above-mentioned pulling-out force "10 N to 80 N / 0.03 m".

As in the above-described embodiment, by using a rotating roller type coating member having an elastic layer or the like,
If the contact condition for facilitating the transfer of the lubricant 7c to the photoreceptor drum 1 and stabilizing the balance between the applied amount of the lubricant 7c and the recovered amount for a long period of time is provided, over the entire area where the applied member contacts. In addition, it is possible to eliminate the adverse effect of other contact units such as the transfer means on the application balance of the lubricant, and to maintain a good application balance. And it can reduce the abrasion of drums and blades, prevent image flow, cleaning blade entanglement, and other problems such as chatter, and thus improve transfer efficiency, enable the use of small particle size toner and spherical toner, etc. Various merits arise.

[0039]

As described above, the image forming apparatus according to the present invention has a developing means for developing an electrostatic latent image formed on the image carrier, and a transferring means for transferring the developed image to transfer paper. Or one or more units having a functional member that comes into contact with the rotating image carrier, such as cleaning means for bringing a blade into contact with the surface of the image carrier after transfer, and applying a coating member to the image carrier. An image forming apparatus provided with an application unit for applying a lubricant to the surface of the image carrier by directly contacting the substrate with the image carrier, wherein the application member is disposed between the base portion and the lubricant to be brought into contact with the image carrier. Because of the configuration having the elastic layer, the coating is performed well even with a weak pressing force of the coating member against the image carrier, and the balance between the coating amount and the collection amount of the developing unit and the transfer unit is stabilized for a long time. The statue above Cleaning failure such as wear and cleaning means lifting member and the like can be prevented.

The base portion of the coating member is a metal core having a cylindrical outer peripheral surface. The elastic layer is provided on the outer peripheral surface of the metal core, and a lubricant layer is provided on the outer peripheral surface of the elastic layer. According to the configuration of the rotating roller having the triple layer structure, it is possible to supply a good lubricant for a long period of time by using the surface area corresponding to the circumference of the roller.

Further, the coating member has a lubricant layer over the entire area in the outer peripheral direction, and the lubricant layer is brought into contact with the image carrier to form a nip, and a peripheral portion relative to the image carrier is formed. According to the configuration capable of rotating with a speed difference, it is possible to further reduce the occurrence of streak-like coating unevenness on the image carrier as occurs in the fixed coating device.

The pressing force of the coating member against the image bearing member may be any value between 10 N and 80 N as a pulling force per 0.03 m width of the paper sandwiched by the nip. For example, there is no wear of the image carrier and it is possible to maintain the friction coefficient without image flow.

According to the configuration in which the lubricant is higher in the same charging series as the toner polarity, the lubricant can be easily transferred to the image carrier even with the weak pressing force and the peripheral speed difference. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration around a photoconductor of an image forming apparatus according to the present exemplary embodiment.

FIG. 2 is a vertical cross-sectional view illustrating an entire configuration of a lubricant supply roller according to the embodiment.

FIG. 3 is a side view showing an apparatus for measuring a coefficient of friction on a drum surface.

FIG. 4 is a diagram illustrating a method of measuring a pressing force of a lubricant supply roller.

FIG. 5 is a diagram illustrating a relationship among a set value of a pressing force of a lubricant supply roller, a number of passed sheets, and a friction coefficient of a drum.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image carrier (photosensitive drum) 4 Developing means (developing roller) 5 Transfer means (transfer roller) 6 Blade 7 Coating member (lubricant supply roller) 7a Base part of coating member (core metal) 7b Elastic layer (polyurethane foam) 7c Lubricant layer (PTFE) 21 paper (3cm width paper)

Claims (7)

[Claims] A developing means for developing the electrostatic latent image formed on the image carrier, a transfer means for transferring the developed image to a transfer paper, or a blade contacting the surface of the image carrier after the transfer. A cleaning unit for rotating the image bearing member, the device including at least one unit having a functional member that comes into contact with the rotating image carrier. An image forming apparatus provided with an application unit for applying an image, wherein the application member has an elastic layer between a base portion thereof and a lubricant to be brought into contact with the image carrier. 2. The base member of the coating member is a metal core having a cylindrical outer peripheral surface, the elastic layer is provided on the outer peripheral surface of the metal core, and a lubricant layer is provided on the outer peripheral surface of the elastic layer. 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a rotating roller having a three-layer structure. 3. The coating member has a lubricant layer over the entire area in the outer peripheral direction, and the lubricant layer is brought into contact with the image carrier to form a nip, and a peripheral portion relative to the image carrier is formed. 3. The image forming apparatus according to claim 2, wherein the image forming apparatus is rotatable with a speed difference. 4. When the peripheral speed ratio when the coating member is at the same peripheral speed as the image carrier and the peripheral speed ratio when the coating member is stopped is 1.0, 4. The image forming apparatus according to claim 3, wherein the rotation direction of the coating member with respect to the image carrier is a forward direction, and the peripheral speed ratio is 0.1 or more. 5. When the peripheral speed ratio when the coating member is at the same peripheral speed as the image carrier and the peripheral speed ratio when the coating member is stopped is 1.0, 4. The image forming apparatus according to claim 3, wherein a rotation direction of the application member with respect to the image carrier is a counter direction, and the peripheral speed ratio is 1.1 or more. 6. The pressing force of the coating member against the image bearing member is any value between 10 N and 80 N as a pulling force per 0.03 m width of the paper sandwiched by the nip. The image forming apparatus according to claim 1, wherein: 7. The image forming apparatus according to claim 1, wherein the lubricant is higher in the same charging series as the toner polarity.