JP2001183859A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device with an easily workable solid lubricant. SOLUTION: In the image forming device 1 with a photoreceptor 3 which supports a toner image and a solid lubricant 17 which supplies its lubricant to the surface of the photoreceptor 3, the solid lubricant 17 is obtained by melting and molding a thermoplastic polymer material having 60-200 deg.C melting point and a linear molecular structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile, and the like.

[0002]

2. Description of the Related Art Generally, an image forming apparatus is provided with a solid lubricant for applying a lubricant to the surface of a photoconductor (image carrier). The friction of the surface is reduced. As the solid lubricant, for example, a material obtained by melt-molding zinc stearate into a bar shape is used, and the lubricant obtained by shaving the bar-shaped solid lubricant little by little is supplied to the surface of the photoreceptor. Has become.
The solid lubricant based on zinc stearate has already been proposed and commercialized.

[0003]

However, a lubricating material used as a solid lubricant has a small cohesive energy between its molecules. In particular, zinc stearate and the like have extremely distorted wall interfaces due to their molecular arrangement. Easy to occur. For this reason, when zinc stearate is processed into a molded body, it often becomes very brittle, and there is a problem that the molding is difficult.

Accordingly, an object of the present invention is to provide an image forming apparatus having a solid lubricant which can be easily processed.

[0005]

According to a first aspect of the present invention, there is provided an image forming apparatus comprising: an image carrier for carrying a toner image; and a solid lubricant for supplying a lubricant to the surface of the image carrier. The solid lubricant has a melting point of 60 ° C. or more and 200
It is characterized in that a thermoplastic polymer material having a linear molecular structure of not more than ° C is melt-molded.

According to the first aspect of the present invention, the melting point of the solid lubricant is set to 60 ° C. or more because the temperature in the image forming apparatus is generally set to be about 50 ° C. When the melting point is less than 60 ° C., the solid lubricant is softened in the image forming apparatus, and it is difficult to stably supply the lubricant to the image carrier.
The solid lubricant preferably has a melting point of 80 ° C. or higher.

The reason why the solid lubricant has a melting point of 200 ° C. or less is that the temperature range which can be used in a general hot melt molding machine (eg, an injection molding machine) is 200 ° C. or less. If the temperature exceeds 200 ° C., it becomes difficult to mold the lubricant using a general hot melt molding machine, so that the specialization of the hot melt molding machine is often caused, and the cost increases, This is because the energy consumption rate depending on the temperature may increase.

Therefore, the melting point is not less than 60 ° C. and 200 ° C.
By using the following solid lubricant, the lubricant can be stably supplied to the image carrier, processing of the solid lubricant is easy, and cost can be reduced. Also, compared to materials with high molding temperatures, less energy is required for molding,
Resources can be protected.

Further, the use of a thermoplastic polymer material having a linear molecular structure as a solid lubricant increases the solid bonding force due to the entanglement of long-chain molecules during molding, resulting in processing into a molded article. Solid lubricant (compact) stronger than zinc stearate, which often becomes very brittle
Is formed, and the hot-melt molding process can be easily performed.

[0010] Since the solid bonding force is strong, handling during the production of the solid lubricant can be facilitated, so that the production cost can be reduced and the yield is good. In addition, since hot melt molding can be easily performed, a solid lubricant having a complicated shape can be easily manufactured, and the shape of the solid lubricant can be freely changed to some extent. In addition, since the shape of the solid lubricant can be freely changed to some extent, the degree of freedom with respect to the installation location of the solid lubricant in the image forming apparatus increases.

According to a second aspect of the present invention, in the first aspect, the solid lubricant has an insulating property and is electrostatically charged by friction with the image carrier. I do.

According to the second aspect of the present invention, the first aspect is provided.
And the solid lubricant is electrostatically charged, so that the lubricant is electrostatically attracted to the surface of the image carrier (electrostatically adsorbed). The agent can be easily supplied to the image carrier, and the supply of the lubricant is improved.

[0013] The invention according to claim 3 is the invention according to claim 1 or 2.
In the invention described in (1), a pressing member that presses the solid lubricant toward the image carrier is provided, and the lubricant is applied by bringing the solid lubricant into contact with the surface of the image carrier.

[0014] According to the third aspect of the present invention, the first aspect is provided.
In addition to the effect similar to that of the invention described in Item 2, the lubricant can be easily applied (supplied) to the image carrier with a simple configuration having only a pressing member.

The invention described in claim 4 is the first or second invention.
In the invention described in (1), a rotation member having a surface in contact with the solid lubricant and the image carrier is provided, and the lubricant is applied to the image carrier by rotation of the rotation member.

[0016] According to the fourth aspect of the present invention, the first aspect is provided.
Or lubrication removed from the solid lubricant by rotating a rotating member (for example, a roller or a brush) that comes into contact with the solid lubricant and the image carrier while having the same operation and effect as the invention described in (2). The agent is applied to the surface of the image carrier. Accordingly, it is possible to prevent unevenness of the lubricant applied to the surface of the image carrier, and to apply the lubricant substantially uniformly to the surface of the image carrier.

The invention according to claim 5 is the invention according to claims 1 to 4
In the invention according to any one of the above, the solid lubricant is disposed in a portion where the surface of the image carrier is not irradiated with light.

According to the fifth aspect of the present invention, there is provided the first aspect.
In addition to providing the same function and effect as the invention described in any one of (1) to (4) above, light is less likely to sneak onto the surface of the image carrier, so that the surface of the image carrier is less likely to generate photoconductivity and the surface of the image carrier is It is almost insulated. The lubricant is electrostatically charged by the friction of the lubricant against the surface of the image carrier.
Therefore, since the lubricant is electrostatically attracted to the image carrier, the lubricant can be easily supplied to the image carrier, and the supply property of the lubricant is improved.

The portion where the surface of the image bearing member is not irradiated with light refers to, for example, a portion where the irradiation of light from the static eliminator or the exposure device is not performed.

The invention according to claim 6 is the invention according to claims 1 to 5
In the invention according to any one of the above, the solid lubricant is disposed in a portion where the surface of the image carrier is not irradiated with light.

According to the sixth aspect of the present invention, a molecular weight of 1
The reason why the polyethylene material having a molecular weight of 0000 or less is used is that if the molecular weight exceeds 10,000, the entanglement of polyethylene molecules becomes strong and it becomes difficult to supply a lubricant to the image bearing member. Therefore, the effects and advantages described in any of claims 1 to 5 are exhibited, and the molecular weight is 1000.
By using a polyethylene material of 0 or less, the lubricant can be easily supplied to the image carrier.

The invention according to claim 7 is the invention according to claims 1 to 6
In the invention according to any one of the above, the solid lubricant is made of a modified polyethylene obtained by partially modifying a polyethylene.

According to the invention described in claim 7, according to claim 1,
The same effects as those of the invention described in any one of the above (1) to (6), and the use of the modified polyethylene makes it possible to control the intermolecular cohesion and the like of the solid lubricant. You can control.

[0024]

Embodiments of the present invention will be described below with reference to the accompanying drawings. First, a first embodiment will be described with reference to FIGS. FIG.
Is an image forming unit 2 of the image forming apparatus 1 according to the present embodiment.
It is a block diagram which shows schematically.

As shown in FIG. 1, the image forming section 2 of the image forming apparatus 1 has a photoreceptor (image carrier) 3, and the surface of the photoreceptor 3 is uniformly charged by a charging roller 5. It is designed to be charged. After an electrostatic latent image is formed on the surface of the photoreceptor 3 by exposure L from an exposure device (not shown), the electrostatic latent image is supplied with toner by a developing sleeve 8 of a developing unit 7 to form a toner image. It is visualized.
The toner image formed on the surface of the photoconductor 3 is transferred by a transfer unit 10 of a transfer unit 9 onto a sheet conveyed from a sheet feeding device (not shown) via a conveying roller 11.

In the image forming section 1, the cleaning blade 13 of the cleaning unit 12 scrapes and removes toner remaining on the surface of the photoconductor 3 after transfer. Between the cleaning blade 11 and the charging roller 5, there is provided a static eliminator (QL) 14 for removing residual charges remaining on the photoconductor 3.

Inside the cleaning unit 12, a lubricant supply unit 15 for applying (supplying) a lubricant to the surface of the photoconductor 3 is provided. As shown in FIG. 2, the lubricant supply unit 15 includes a holding holder 19 that holds the solid lubricant 17.
, A supply roller 21 and a cleaning brush 23. The solid lubricant 17 is supplied to the supply roller 2 at a predetermined pressure.
1 so that the spring 25 of the holding holder 19
Pressurized. The supply roller 21 is configured to scrape the solid lubricant 17 by its rotation, and the lubricant scraped by the supply roller 21 is removed by the cleaning brush 23.
Is supplied to the surface of the photoconductor 3.

The reason why the lubricant is supplied to the photoconductor 3 is to prevent the life of the photoconductor 3 from being shortened due to wear. That is,
If the photosensitive layer of the photoconductor 3 is scraped to some extent, the photoconductor 3
This is because the electrical characteristics of the device change, and a predetermined image forming process cannot be performed. This abrasion occurs in all the portions where the photoconductor 3 contacts other image forming units in the image forming process.

In particular, the cleaning blade 13 that mechanically removes the toner remaining on the photoconductor 3 has a large amount of wear, and the wear on the units other than the cleaning blade 13 does not significantly affect the actual life of the photoconductor 3. The wear caused by the cleaning blade 13 is mainly divided into two forms.

One is abrasion caused by the shearing force generated between the photoconductor 3 and the cleaning blade 13, and the other is that the toner is sandwiched between the cleaning blade 13 and the photoconductor 3 and acts like a grindstone. , Wear and rough wear. The factors that determine the wear include the photoconductor 3
Of photoreceptor 3 of cleaning blade 13
, The composition of the toner particles, the coefficient of surface friction of the photoconductor 3 (the lower the wear amount, the lower the abrasion amount).

Therefore, in the present embodiment, the solid lubricant 1
Reference numeral 7 is provided to reduce the coefficient of friction of the surface of the photoconductor 3. When the lubricant is supplied to the surface of the photoconductor 3, the photoconductor 3
The coefficient of friction between the photoconductor 3 and the cleaning blade 13 is reduced, and the amount of wear of the photoconductor 3 can be reduced. When the coefficient of static friction of the photoreceptor 3 is 0.4 or less as measured by the Euler belt method from the viewpoint of the abrasion, it is known that the abrasion amount of the photoreceptor 3 is sufficiently reduced.

Here, the Euler belt system will be described. A belt-shaped measurement portion obtained by cutting a medium-thick high-quality paper so that the paper-drawing direction is the longitudinal direction is brought into contact with the outer periphery 1/4 portion of the surface of the photoreceptor 3, and a load (eg,
g), and after connecting the force gauge to the other side (after installation), pull this force gauge and read the value (load) of the force gauge when the belt starts to move. It is calculated by:

[0033]

Μs = 2 / π × ln (F / W) (1) where μs: coefficient of static friction F: measured value W: load In the present embodiment, a lubricant is supplied to the surface of the photoconductor 3 By doing so, the coefficient of static friction of the photoconductor 3 calculated by the above equation (1) is set to 0.4 or less. However, when not only maintaining the value of 0.4 or less always, but also controlling the amount of wear to some extent, it is preferable to set the value of 0.1 at any time.
It may be more than four. Further, it can be controlled to 0.3 to 0.1 as a region having a higher effect on abrasion. In this case, it was observed that the wear amount of the photoconductor 3 was further reduced.

The lower limit of the static friction coefficient of the photosensitive member 3 is as follows.
It is desirable not to drop below 0.08. Photoconductor 3
If the static friction coefficient of the sample is reduced to 0.08 or less, an image defect may occur due to the influence of ionized adhered substances and the like. Note that an image defect is not always generated when the static friction coefficient is equal to or less than 0.08 because the image defect also depends on environmental conditions and the like. Therefore, the lower limit of the static friction coefficient of the photoconductor 3 may be arbitrarily set according to the environmental conditions.

In the present embodiment, a material having a melting point of 60 ° C. or more is selected as the solid lubricant 17. That is, when the solid lubricant 17 solidified as a molded body of the lubricant is disposed in the image forming apparatus 1 as in the present embodiment, the solid lubricant 1
As 7, it is preferable to select a material having a melting point of 60 ° C. or higher. Further, a material having a melting point of 80 ° C. or more is preferable. This is because, when the lubricating material has a low melting point typified by silicone oil or the like, the shape stability after molding is poor.

In general, the temperature inside the image forming apparatus 1 is usually set so as to be generally about 50 ° C. or less. An experiment in which an image forming apparatus having a temperature of 50 ° C. and a material having a melting point of 60 ° C. or lower were left (a test at 50 ° C.).
Was performed, the softening started even when the melting point was not reached in the machine, and the scraping amount with a brush or the like became unstable. That is, it was confirmed that the supply amount of the lubricant to the photoconductor 3 changed depending on the temperature inside the apparatus.

As an example, when an experiment was conducted using an alkoxy-modified unreacted silicone oil (melting point: 55 ° C.), when the supply amount was 25 ° C. and 50 ° C. in the machine, the supply method was the same. In the case of (supply by the lubricant supply unit 15 in FIG. 2), the supply amount at 50 ° C. may be more than five times that at 25 ° C., and environmental stability could not be maintained.

On the other hand, when a similar experiment was conducted using PE (polyethylene) having a melting point of 80 ° C. or higher,
The supply amount at 0 ° C. is approximately 1.1 to 1.1 at 25 ° C.
It was reduced to about 5 times, and it became possible to supply it stably.

As the material of the solid lubricant 17, a thermoplastic material is used. When the lubricant is solidified as the solid lubricant 17, the lubricant can be installed in the image forming apparatus 1 in a state of a component, so that the assembling property is improved. In addition, if the hot-melt molding process can be performed, the shape can be freely changed to some extent, and the degree of freedom for installation can be increased. In particular, when the solid lubricant 17 is provided around the photoconductor 3, the space often requires a complicated shape due to entanglement with other members. In contrast, in melt molding,
Even if the solid lubricant 17 has a complicated shape under molding conditions such as a complicated mold shape, it can be provided at low cost. In addition, since solid lubricants 17 having various shapes can be easily produced, it is possible to optimize the supply of the lubricant.

As a material for the solid lubricant 17, a linear polymer is used. When a linear polymer is used, the entanglement of long-chain molecules at the time of molding increases the solid bonding force, so that a stronger molded article can be formed as compared with zinc stearate having a low molecular weight. As a result of specific experiments, for example, if PE has a molecular weight of about 400 or more,
It was confirmed that the rigidity and strength of the molded product were superior to those of zinc stearate. As described above, when the solid bonding force is strong, handling when manufacturing the molded body can be relatively easily performed, the manufacturing cost can be reduced, and the yield is good.

The material of the solid lubricant 17 has a melting point of 2
Those having a temperature of 00 ° C or less are used. Thus, the solid lubricant 17 can be molded using a general resin material hot melt molding machine (for example, an injection molding machine or the like), and it is not necessary to use a dedicated machine. Therefore, there is an advantage that the cost of molding can be performed in the same manner as general resin molding.
Although a material having a melting point of 200 ° C. or less can be arbitrarily selected, PE is shown as an example. The melting point of PE is generally from about 80 ° C. to about 130 ° C., depending on the average molecular weight. That is, P
Since the molding temperature of E is 200 ° C. or lower, which is a temperature range that can be used in a general injection molding machine or the like, molding under arbitrary conditions becomes possible.

On the other hand, a fluorine-based resin such as PTFE (polytetrafluoroethylene) whose function is recognized as a lubricant often has a molding temperature of 300 ° C. or higher. For this reason, a general injection molding machine or the like cannot be used, which often leads to specialization of the apparatus, and there is a tendency that problems such as a high cost or an energy consumption rate due to the molding temperature are increased. Therefore, a material having a low molding temperature, such as PE, requires less energy for molding than a fluororesin or the like whose molding temperature is about 300 ° C.,
Excellent in resource conservation.

The solid lubricant 17 satisfying the conditions described above
In the present embodiment, PE is used as the material for.
The results of comparison between the lubricity of this PE and the lubricity of PTFE are shown in Table 1 below.

[0044]

[Table 1] Comparison of friction coefficient

According to Table 1, although the coefficient of friction of PE slightly decreased, the lubricity thereof was extremely remarkable as compared with that of PTFE, and there was no problem in the performance as a lubricant.
In Table 1, “Polymer / Polymer” means PTFE
Is the coefficient of friction when rubbing each other or PEs, "polymer / steel" is the coefficient of friction when rubbing steel against PTFE or PE, and "steel / polymer" is PT
It is a coefficient of friction when FE or PE is rubbed.

The molecular structure of PE is linear as in PTFE, as shown in the following molecular formula (1). However, while PTFE has no branch structure, PE
Has been confirmed to have many branches, as shown in FIG. Therefore, considering the structure of this PE, P
It is considered that the displacement of the wall interface is less likely to occur as compared with TFE.

[0047]

Embedded image — (CH ₂ —CH ₂ ) _—n (1) PE has more entanglement of molecules than PTFE, and therefore the coefficient of friction of the photoreceptor 3 depends on its molecular weight (average). This is because when PE as a lubricant is applied to the surface of the photoreceptor 3, displacement of the wall interface is less likely to occur due to entanglement of PE molecules, and the friction coefficient of the photoreceptor 3 surface increases. Therefore, by changing the molecular weight of PE, the photoreceptor 3
After the PE is applied to the photoconductor 3, the friction coefficient of the photoconductor 3 can be controlled. For example, PE having a molecular weight of 400,
In the case of PE having a molecular weight of 5,000, PE having a slight molecular weight of 5000 is inferior in lubricity.

An experiment was conducted by allocating the molecular weight of PE to a plurality of values. When the molecular weight exceeded 10,000, the entanglement of the molecules became strong, and after shaping the solid lubricant 17, the solid lubricant 17 was scraped off by the cleaning brush 23. It was confirmed that it would be difficult. Therefore, in the present embodiment, in order to ensure the supply of the lubricant, the molecular weight is 1000
PE of 0 or less is used. The molecular weight of PE is 100
Although it is not particularly limited as long as it is 00 or less, as described above,
When the molecular weight of PE is 400 or more, the solid bond becomes strong. Therefore, it is preferable to use PE having a molecular weight of 400 or more and 10,000 or less.

On the other hand, in order to facilitate the supply of the lubricant from the solid lubricant 17 to the photoreceptor 3 (to improve the supply of the lubricant), the lubricant from the solid lubricant 17 is supplied to the photoreceptor 3. At this stage, it is desirable that the lubricant be electrostatically charged by friction with the photoconductor 3. That is, when the lubricant is charged, the lubricant is electrostatically attracted (electrostatically attracted) to the photoconductor 3 and the lubricant adheres to the photoconductor 3. When the lubricant is charged, it is particularly effective for the initial adsorption to the photoconductor 3. The higher the lubricity of the lubricant, the higher the electrostatic adsorption, and the lower the friction coefficient of the photoconductor 3. Is faster with respect to the supply time. Therefore, when a material having a high chargeability is used, the supply property of the lubricant increases.

In order to electrostatically charge the lubricant, the solid lubricant 17 is basically required to have electrically stable insulation. In order to make the solid lubricant 17 have insulating properties, the solid lubricant 17 preferably has a volume resistance of 10 ¹⁰ Ω · m or more. On the other hand, PE used in the present embodiment has a volume resistivity of about 10 ¹⁵ Ω · m or more even if it is a low molecular weight material / high acid value type. The electrostatic adsorption depends on the ratio (Q / M) of the charge amount Q to the mass M. The larger the Q / M is, the easier the adsorption is. Therefore, the smaller the size of the solid lubricant 17 is, the better. It is desirable to supply in the following size.

In the case where electrostatic attraction is performed, it is desirable that the photosensitive member 3 on the partner side has high insulation properties. However, the photoreceptor 3 is generally an optical semiconductor, and in a portion to which the light from the static eliminator 14 or the exposure L is irradiated, the photoreceptor 3 is not strictly insulated, and the electrostatic attraction hardly occurs. Therefore, it is desirable that the solid lubricant 17 is arranged in a place where the surface of the photoconductor 3 is not irradiated with light.

In the present embodiment, as described above, the lubricant supply unit 15 is disposed inside the cleaning unit 10 (see FIG. 1). By arranging the lubricant supply unit 15 inside the cleaning unit 10, the sneak of light from the static eliminator 14 and the like are small, and the photoconductor 3 is almost in an insulated state, so that electrostatic attraction easily occurs. The location of the lubricant supply unit 15 is not limited to the inside of the cleaning unit 10 and may be any location where the surface of the photoconductor 3 is not irradiated with light.

The lubricant (PE particles) from the solid lubricant 17 composed of PE is supplied to the surface of the photoreceptor 3 via the cleaning brush 23. At this time, the lubrication is caused by friction with the photoreceptor 3 The agent is negatively charged. It is considered that this is because PE (polycarbonate), which is a material forming the surface of the photoconductor 3, has a negative charge sequence of PE. The measurement of the charge amount can be performed by using a system (blow-off device) for measuring the charge amount of the toner.

The lubricant adhering to the surface of the photoreceptor 3 also exerts a physical force such as a Van der Waals force to form a molecular layer on the surface of the photoreceptor 3. Since the lubricant is electrostatically charged, the lubricant is electrostatically adsorbed on the surface of the photoconductor 3, so that the lubricant is easily supplied to the surface of the photoconductor 3. In addition, the lubricant quickly adheres to the photoreceptor 3 and can have a predetermined friction coefficient, so that abrasion on the surface of the photoreceptor 3 can be reduced.

Next, another embodiment will be described. Parts having the same functions and effects as those of the above-described embodiment are denoted by the same reference numerals, and detailed description of those parts will be omitted.

The second embodiment differs from the first embodiment in that a modified PE in which a part of the PE is denatured is used as the material of the solid lubricant 17. That is, by using the modified PE represented by the following molecular formula (2), the branched structure is intentionally increased, thereby controlling the intermolecular cohesive force, slip (collapse), and the like of the solid lubricant 17.

[0057]

Embedded image When an experiment was performed using the modified PE represented by the above molecular formula (2), the friction coefficient of the photoreceptor 3 could be reduced to about ４ to ／ of that of ordinary PE. in this way,
By enabling the control of the coefficient of friction, development characteristics, transfer characteristics, and the like can be controlled. Although the functional group of the above molecular formula (2) is a methyl group, it may be substituted with an alkyl group or the like, and the functional group can be arbitrarily selected according to each characteristic.

FIG. 4 is a sectional view schematically showing a lubricant supply section 15 according to the third embodiment. The third embodiment is different from the first embodiment in that the cleaning brush (rotating member) 23 is brought into contact with the photoreceptor 3 and the solid lubricant 17 without providing the supply roller 21.

As the cleaning brush 23 rotates, the lubricant removed from the solid lubricant 17 is supplied to the surface of the photoreceptor 3. Therefore, it is possible to prevent unevenness of the lubricant supplied to the surface of the photoconductor 3 and to supply the lubricant to the surface of the photoconductor 3 substantially uniformly.

FIG. 5 is a sectional view schematically showing a lubricant supply section 15 according to the fourth embodiment. In the third embodiment, the solid lubricant 17 is directly contacted (pressed) with the photoconductor 3 by the spring (pressing member) 25 of the holding holder 19 without providing the supply roller 21 and the cleaning brush 23. , Is different from the first embodiment. In the third embodiment, the lubricant can be easily supplied to the photoreceptor 3 with a simple configuration in which only the spring 25 is provided.

FIG. 6 is a configuration diagram schematically showing an image forming section 31 of an image forming apparatus 30 according to the fourth embodiment.

As shown in FIG. 6, the image forming section 31 of the image forming apparatus 30 has a photosensitive member (image carrier) 3.
The electrostatic latent image formed on the photoconductor 3 is transferred to the first
The toner is developed as a first color toner image by the developing device 32a. The developed toner image is transferred to the intermediate transfer belt 33.
Is transferred to Then, the photoconductor 3 is uniformly charged again to form a second color electrostatic latent image, and the second color toner image is developed by the second developing device 32b. The developed toner image is transferred so as to overlap the first color toner image on the intermediate transfer belt 33.

Similarly, the third and fourth developing devices 32c,
By 32d, a full-color image is obtained by superimposing the toner image of the third color and the toner image of the fourth color on the intermediate transfer belt 33. The full-color image on the intermediate transfer belt 33 is collectively transferred by the transfer unit 9 onto the sheet sent from the transport roller 11. Although not shown, the image forming apparatus 31 includes a charger for charging the photoreceptor 3, a photosensitive durable cleaning unit for cleaning the photoreceptor 3, an intermediate transfer belt cleaning unit for cleaning the intermediate transfer belt 33, and the like. Is provided.

The intermediate transfer belt 15 is provided with the same lubricant supply section 15 as in the second embodiment. As in the present embodiment, the solid lubricant 17 is
Can also be used to reduce the friction coefficient. It is needless to say that also in the present embodiment, the lubricant supply unit 15 of the first embodiment and the lubricant supply unit 15 similar to the third embodiment may be provided.

[0065]

According to the first aspect of the present invention, the melting point is 60.
By using a solid lubricant at a temperature of not less than 200 ° C. and not less than 200 ° C., the lubricant can be stably supplied to the image bearing member, and the processing of the solid lubricant is easy and the cost can be reduced. In addition, compared to a material having a high molding temperature, less energy is required for molding, and resources can be protected.

On the other hand, since the solid bonding force is strong,
Since the handling at the time of producing the solid lubricant can be facilitated, the production cost can be reduced and the yield is good. In addition, since hot melt molding can be easily performed, a solid lubricant having a complicated shape can be easily manufactured, and the shape of the solid lubricant can be freely changed to some extent. In addition, since the shape of the solid lubricant can be freely changed to some extent, the degree of freedom with respect to the installation location of the solid lubricant in the image forming apparatus increases.

According to the second aspect of the present invention, the same effect as that of the first aspect of the invention is provided, and the solid lubricant is electrostatically charged, so that the lubricant is electrostatically charged on the image carrier. Since the lubricant is attracted to the surface, the lubricant can be easily supplied to the image carrier, and the supply of the lubricant is improved.

According to the third aspect of the present invention, the same effect as that of the first or second aspect of the present invention is obtained, and the lubricant is easily applied to the image carrier with a simple structure having only the pressing member. can do.

According to the fourth aspect of the present invention, the same effect as that of the first or second aspect of the invention can be obtained, and the unevenness of the lubricant applied to the surface of the image carrier can be prevented. The lubricant can be applied to the surface substantially uniformly.

According to the fifth aspect of the present invention, the same effects as those of the first to fourth aspects of the present invention are obtained, and light is less likely to be transmitted to the surface of the image carrier.
The surface of the image carrier hardly generates photoconductivity, and the surface of the image carrier becomes almost insulated. The lubricant is electrostatically charged by the friction of the lubricant against the surface of the image carrier. Therefore,
Since the lubricant is electrostatically attracted to the image carrier, the lubricant can be easily supplied to the image carrier, and the supply of the lubricant is improved.

According to the sixth aspect of the present invention, the effects described in any one of the first to fifth aspects can be obtained, and the molecular weight is 1
By using a polyethylene material of 0000 or less,
Lubricant is easily supplied by the image carrier.

According to the seventh aspect of the present invention, the same effects as those of the first to sixth aspects of the invention can be obtained, and the intermolecular cohesion of the solid lubricant can be controlled by using the modified polyethylene. Therefore, the coefficient of friction on the surface of the image carrier can be controlled.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing an image forming unit of an image forming apparatus according to a first embodiment.

FIG. 2 is a sectional view schematically showing a lubricant supply unit.

FIG. 3 is a diagram showing a molecular structure of polyethylene which is a material of a solid lubricant.

FIG. 4 is a sectional view schematically showing a lubricant supply unit according to a second embodiment.

FIG. 5 is a sectional view schematically showing a lubricant supply unit according to a third embodiment.

FIG. 6 is a configuration diagram schematically illustrating an image forming unit of an image forming apparatus according to a fourth embodiment.

[Explanation of symbols]

 1, 30 Image forming apparatus 3 Photoreceptor (image carrier) 17 Solid lubricant 23 Cleaning brush (rotating member) 25 Spring (pressing member) 33 Intermediate transfer belt (image carrier)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yota Sakon 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Akiyo Nakajima 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. (72) Inventor Nobuto Yokokawa 1-3-6 Nakamagome, Ota-ku, Tokyo F-term in Ricoh Co., Ltd. 2H034 AA07 2H068 AA06 BB03 BB31 BB63 BB64 EA07 FA03 FC15

Claims (7)

[Claims] 1. An image forming apparatus comprising: an image carrier for carrying a toner image; and a solid lubricant for supplying a lubricant to the surface of the image carrier, wherein the solid lubricant has a melting point of not less than 60 ° C. and not less than 200 ° C. An image forming apparatus comprising a thermoplastic polymer material having a linear molecular structure of not more than 100 ° C., which is formed by melt molding. 2. The image forming apparatus according to claim 1, wherein the solid lubricant has an insulating property and is electrostatically charged by friction with the image carrier. 3. The image forming apparatus according to claim 1, further comprising a pressing member for pressing the solid lubricant toward the image carrier, wherein the solid lubricant is applied to the surface of the image carrier by bringing the solid lubricant into contact therewith.
An image forming apparatus according to claim 1. 4. The image forming apparatus according to claim 1, further comprising a rotating member having a surface in contact with the solid lubricant and the image carrier, wherein the lubricant is applied to the image carrier by rotation of the rotating member. Image forming device. 5. The image forming apparatus according to claim 1, wherein the solid lubricant is disposed in a portion where the surface of the image carrier is not irradiated with light. 6. The image forming apparatus according to claim 1, wherein the solid lubricant is made of a polyethylene material having a molecular weight of 10,000 or less. 7. The image forming apparatus according to claim 1, wherein the solid lubricant is made of a modified polyethylene obtained by partially modifying a polyethylene.