JP2011128392A - Cleaning device and image forming apparatus - Google Patents

Abstract

Provided are a cleaning device and an image forming apparatus that have little deterioration with time and excellent cleaning controllability.
In a cleaning device provided with a cleaning roller that electrostatically removes charged fine powder on the surface of the object to be cleaned in proximity to or in contact with the object to be cleaned, a positive potential is applied to the surface of the cleaning roller. The cleaning device includes a first region 71e having a second region 71f having a negative potential, and the second region 71f is made of a negative electret material containing an amorphous fluororesin and an aminosilane compound.
[Selection] Figure 4

Description

  The present invention relates to a cleaning device and an image forming apparatus for removing transfer residual toner.

  2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus, unnecessary charged fine powder adhered to a surface after a toner image is transferred to a recording body or another image carrier, such as an image carrier or an intermediate transfer body. The residual transfer toner is removed by a cleaning device. As a cleaning member of this cleaning device, one using a cleaning blade is well known because it can generally be simplified in configuration and has excellent cleaning performance.

  Further, in order to meet the recent demand for higher image quality, an image forming apparatus using a nearly spherical toner (hereinafter referred to as “spherical toner”) formed by a polymerization method or the like is known. This spherical toner has characteristics such as higher transfer efficiency than conventional pulverized toner (unshaped toner), and is known to be able to meet the recent demand for higher image quality. However, as shown in FIG. 13, after the spherical toner 103 is dammed up by the cleaning blade 102, it rolls by the frictional force with the photosensitive member 101 and slips through the cleaning blade 102, thereby deteriorating the cleaning performance.

  On the other hand, there is an electrostatic brush cleaning method as a cleaning method having a reliable cleaning property even when cleaning a small particle size toner or a spherical toner. FIG. 14 is a schematic configuration diagram of the electrostatic brush cleaning device 110. The electrostatic brush cleaning device 110 disposes the toner from the brush by disposing the conductive brush roller 111 so as to contact and rub against the surface of the photosensitive member 101 and repelling the toner adhering to the brush of the conductive brush roller 111. Flicker 112 is provided as a removing means. A voltage is applied to the conductive brush roller 111 from the power supply 113, and the toner is removed from the photosensitive member by an electrostatic force in addition to the rubbing force. For this reason, the cleaning performance can be obtained even with respect to a small particle size toner or a spherical toner.

  In general, in an image forming apparatus, a toner having a polarity opposite to that of a developed toner is applied in a transfer process to transfer the toner on the photoreceptor, so that the toner remaining on the photoreceptor after the transfer is the toner polarity after development. It is a mixture of the toner as it is and the toner charged to the opposite polarity. As a cleaning device for cleaning this bipolar mixture, a cleaning device 120 as shown in FIG. 15 has been proposed. That is, the first conductive brush roller 121 to which a positive voltage is applied from the power source 131 and the second conductive brush roller 122 to which a negative voltage is applied from the power source 132 are arranged and cleaned for each polarity toner. Is.

However, it is possible to dispose two conductive brush rollers 121 and 122 so as to face the photoconductor 101 and to dispose toner collecting devices 123 and 124 that collect toner attached to the respective brushes. It is difficult to achieve the problem of downsizing.
Therefore, Patent Document 1 proposes a cleaning device including a conductive brush roller that cleans the toner for each polarity toner without increasing the size. In the conductive brush roller of Patent Document 1, a positive bias is applied to a plurality of conductive nappings, and a negative bias is applied to the first region where the plurality of nappings have a positive potential and napping. Thus, the plurality of raised portions are divided into second regions having a negative potential. Then, the brush roller divided into the positive and negative areas is rotated so that each of the brush rollers comes into contact with the surface of the photoconductor, and cleaning is performed for each polar toner from the surface of the photoconductor. Accordingly, it is only necessary to arrange one brush roller so as to face the image carrier, and this is advantageous in terms of downsizing. Furthermore, Patent Document 2 succeeds in collecting positive and negative toners with a single roller using a cleaning roller in which positive and negative electret materials are alternately arranged without using an electrostatic brush. Yes.

  In the electrostatic brush cleaner of Patent Document 1, the first region having a positive potential and the second region having a negative potential are configured by a plurality of raised portions that can be easily deformed. When the contact with the photosensitive member occurs, the raised hair is deformed, and the raised hair in the first region and the raised hair in the second region may come into contact with each other and leak. If the leakage occurs, the potentials of the first region and the second region decrease, and the transfer residual toner cannot be electrostatically adsorbed by the brush, resulting in a problem of defective cleaning. For this reason, it is conceivable that the raising is coated with an insulating member to prevent leakage even if the raising in the first region and the raising in the second region come into contact with each other. However, when the insulating coating material applied to the surface of the brushed brush is lost due to wear over time, the conductive portions are exposed, and furthermore, the exposed portions come into contact with each other to cause leakage. There was a problem that the cleaning ability was greatly reduced.

  The invention disclosed in Patent Document 2 solves such a problem, and achieves toner cleaning by using a permanent charging member, that is, an electret material. Using a cleaning roller in which positive and negative electret materials are alternately arranged, positively or negatively charged toner is once captured in each electret material portion of opposite polarity and cleaned with a brush or the like It is. Certainly, it does not use a power supply device at all, and has an excellent feature in terms of downsizing of the device. First, the electret property is deteriorated with time, and secondly, the toner has a fixed potential. The lack of controllability of cleaning with respect to the input amount, and thirdly, the difficulty of processing the cleaning roller exist as problems.

  The present invention has been made in view of the above-described problems, and the object of the present invention is to suppress the increase in size of the device while satisfactorily removing the charged fine powder of each polarity with a single roller, and the layout in the device. It is an object of the present invention to provide a cleaning apparatus and an image forming apparatus that can suppress a decrease in the degree of freedom of the apparatus, suppress an increase in cost of the apparatus, have little deterioration with time, and have excellent cleaning controllability.

（式中、ｎは繰り返し単位数である。）
４．本発明のクリーニング装置は、さらに、上記アミノシラン化合物が、下記一般式（２）で表されるアミノシラン化合物であることを特徴とする。

（式中、ＹはＮＨ_２または（ＣＨ_２）_ｊ−ＮＨ_２を示し、Ｒは（ＣＨ_２）_ｋＣＨ_３を示す。ｍは１または２、ｊおよびｋは１、２または３である。）
５．本発明のクリーニング装置は、さらに、上記第２領域の負極性エレクトレット材料が、電子線照射により永久帯電処理されたものである
ことを特徴とするクリーニング装置
６．本発明のクリーニング装置は、さらに、上記クリーニングローラに当接し、上記クリーニングローラに付着した帯電微粉を堰き止めて、該帯電微粉を上記クリーニングローラ表面の該帯電微粉の帯電極性と異なる極性の領域と対向させるスクレーパ部材を備えたことを特徴とする。
７．本発明のクリーニング装置は、さらに、上記スクレーパ部材および上記クリーニングローラのいずれか一方が弾性変形するように、上記スクレーパ部材を上記クリーニングローラに当接させたことを特徴とする。
８．本発明のクリーニング装置は、さらに、上記被清掃体と上記クリーニングローラとの対向領域において、上記被清掃体と上記クリーニングローラとの間に線速差が生じるように構成したことを特徴とする。
９．本発明のクリーニング装置は、さらに、上記被清掃体表面が上記クリーニングローラとの対向領域を通過する間に、上記第１領域および第２領域と上記被清掃体表面とが少なくとも一回以上接触するように構成したことを特徴とする。
１０．本発明のクリーニング装置は、さらに、上記第１領域と上記第２領域とを上記帯電微粉の平均粒径以上のピッチで配置したことを特徴とする。
１１．本発明のクリーニング装置は、さらに、上記第１領域および上記第２領域が、櫛形状のパターンで上記クリーニングローラ表面に形成されたことを特徴とする。
１２．像担持体と、該像担持体を帯電する帯電装置と、該像担持体に静電潜像を形成する潜像形成装置と、該像担持体上の静電潜像にトナーを付着させて顕像化する現像装置と、該像担持体上のトナー像を転写材に転写する転写装置と、該像担持体をクリーニングするクリーニング装置とを備えた画像形成装置において、上記クリーニング装置として請求項１ないし１０のいずれかに記載のクリーニング装置を用いることを特徴とする。
１３．本発明のクリーニング装置は、さらに、上記像担持体上にトナー像を形成するためのトナーとして、形状係数ＳＦ−１が１００〜１５０の範囲にあるものを用いることを特徴とする。 The features of the present invention, which is a means for solving the above problems, are listed below.
1. The cleaning device of the present invention is a cleaning device provided with a cleaning roller that comes close to or abuts on the object to be cleaned and electrostatically removes the charged fine powder on the surface of the object to be cleaned.
The cleaning roller surface includes a first region having a positive potential and a second region having a negative potential, and the second region is made of a negative electret material containing an amorphous fluororesin and an aminosilane compound. It is characterized by comprising.
2. The cleaning device of the present invention is further characterized in that the first region having a positive potential is constituted by an electrode having a variable potential.
3. The cleaning device of the present invention is further characterized in that the amorphous fluororesin is a fluororesin represented by the following general formula (1).

(In the formula, n is the number of repeating units.)
4). The cleaning apparatus of the present invention is further characterized in that the aminosilane compound is an aminosilane compound represented by the following general formula (2).

(In the formula, Y represents NH ₂ or (CH ₂ ) _j —NH ₂ , R represents (CH ₂ ) _k CH ₃ , m is 1 or 2, j and k are 1, 2 or 3. )
5. 5. The cleaning device according to the present invention is further characterized in that the negative electret material in the second region has been subjected to permanent charging treatment by electron beam irradiation. The cleaning device of the present invention further contacts the cleaning roller, dams up the charged fine powder adhering to the cleaning roller, and causes the charged fine powder to have a region having a polarity different from the charged polarity of the charged fine powder on the surface of the cleaning roller. A scraper member to be opposed is provided.
7). The cleaning device of the present invention is further characterized in that the scraper member is brought into contact with the cleaning roller so that one of the scraper member and the cleaning roller is elastically deformed.
8). The cleaning device of the present invention is further characterized in that a linear velocity difference is generated between the object to be cleaned and the cleaning roller in a region where the object to be cleaned and the cleaning roller are opposed to each other.
9. In the cleaning device of the present invention, the first region and the second region and the surface of the object to be cleaned contact each other at least once while the surface of the object to be cleaned passes through the region facing the cleaning roller. It is configured as described above.
10. The cleaning device of the present invention is further characterized in that the first region and the second region are arranged at a pitch equal to or larger than the average particle diameter of the charged fine powder.
11. The cleaning device of the present invention is further characterized in that the first region and the second region are formed on the surface of the cleaning roller in a comb-shaped pattern.
12 An image carrier, a charging device for charging the image carrier, a latent image forming device for forming an electrostatic latent image on the image carrier, and a toner attached to the electrostatic latent image on the image carrier. An image forming apparatus comprising: a developing device that visualizes; a transfer device that transfers a toner image on the image carrier to a transfer material; and a cleaning device that cleans the image carrier. The cleaning apparatus according to any one of 1 to 10 is used.
13. The cleaning device of the present invention is further characterized in that a toner having a shape factor SF-1 in the range of 100 to 150 is used as a toner for forming a toner image on the image carrier.

According to the present invention, the charged fine powder charged to the negative polarity on the surface to be cleaned is removed in the first region having the positive potential on the surface of the cleaning roller, and the positive electrode in the second region having the negative potential on the surface of the cleaning roller. By removing the charged fine powder, the bipolar charged fine powder on the surface to be cleaned can be removed with a single cleaning roller. Therefore, the apparatus can be reduced in size as compared with the case where two rollers to which positive and negative voltages are respectively applied are arranged. In addition, since the first region and the second region are formed on the surface of the cleaning roller, the first region and the second region are compared with those in which the first region and the second region are formed by a plurality of brushed brush brushes. Can be prevented from coming into contact with each other. Therefore, leakage caused by contact between the first region and the second region can be suppressed, a decrease in potential of the first region and the second region can be suppressed, and good cleaning performance can be maintained. Can do.
Further, by configuring the first region with a positive variable potential and forming only the second region with a material having excellent electret properties, the power supply device can be one of the positive power sources, and further cleaning control can be performed. It became possible to acquire sex. By reducing the power source, it is possible to suppress a decrease in the degree of freedom of layout in the apparatus, to suppress an increase in the number of parts of the apparatus, and to suppress an increase in cost.

1 is a schematic configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention. It is an enlarged block diagram of the cleaning apparatus shown in FIG. It is a schematic block diagram of the cleaning roller shown in FIG. It is a figure which shows the mode of the electric field of the cleaning roller surface which concerns on one Embodiment of this invention. It is a figure which shows a mode that the scraper member of the cleaning apparatus which concerns on one Embodiment of this invention removes the transfer residual toner adhering to the cleaning roller surface. It is a figure explaining the contact state of the scraper member and cleaning roller of the cleaning apparatus which concerns on one Embodiment of this invention. FIG. 6 is a diagram for explaining how to remove transfer residual toner on the surface of the photosensitive member when the linear velocity of the cleaning roller is made slower than the linear velocity of the photosensitive member. (A) is a figure explaining the mode of the electric field which affects a toner when an electrode pitch is smaller than the particle size of a toner, (b) is a toner when an electrode pitch is larger than the particle size of a toner. It is a figure explaining the mode of the electric field which influences. It is a figure which shows the cleaning roller and photoconductor with a large electrode pitch L. It is a figure explaining the fluororesin coating sheet preparation procedure in the manufacturing method of the cleaning roller of Example 1 thru | or 3. It is a figure explaining the cleaning roller manufacturing method of Example 1 and 2. FIG. It is a figure explaining the cleaning roller manufacturing method of Example 3. FIG. FIG. 4 is a diagram illustrating a state where spherical toner passes through a cleaning blade. It is a figure which shows an example of the conventional cleaning apparatus. It is a figure which shows the other example of the conventional cleaning apparatus.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated based on drawing. Note that it is easy for a person skilled in the art to make other embodiments by changing or correcting the present invention within the scope of the claims, and these changes and modifications are included in the scope of the claims. The following description is an example of an embodiment of the present invention, and does not limit the scope of the claims.

An embodiment in which the present invention is applied to a printer as an image forming apparatus will be described with reference to FIG. FIG. 1 is an overall configuration diagram of a printer according to the present embodiment.
Around the photosensitive member 1 as an image carrier, a charging device 2 that charges the surface of the photosensitive member 1 with a charging roller 2a, and an exposure device 3 that forms a latent image on the uniformly charged surface of the photosensitive member 1 with a laser beam L. The toner image formed on the photosensitive member 1 by the developing device 6 as a developing means for forming a toner image by attaching charged toner to the latent image on the photosensitive member 1 and the transfer roller 12a is applied to the transfer paper P. A transfer device 5 for transferring, and a cleaning device 7 for removing toner remaining on the photosensitive drum 1 after the transfer are sequentially arranged.
In the printer having the above configuration, the photosensitive member 1 whose surface is uniformly charged by the charging roller 2a of the charging device 2 forms an electrostatic latent image by the exposure device 3, and forms a toner image by the developing device 6. The toner image is transferred onto the transfer paper P conveyed from the surface of the photoreceptor 1 by the transfer device 5.

  Below the transfer device 5, a paper feed cassette 4 that stores a plurality of transfer papers P as recording bodies is disposed. The paper feed cassette 4 rotates the paper feed roller 4a pressed against the uppermost transfer paper P at a predetermined timing, and feeds the transfer paper P to the paper feed path. In the paper feed conveyance path, the transferred transfer paper P passes through the plurality of conveyance roller pairs 13 and then is sandwiched between the rollers of the registration roller pair 14 and stopped. The registration roller pair 14 faces the transfer nip between the transfer roller 12a and the photoconductor 1 at a timing at which the sandwiched transfer paper P can be superimposed on the toner image formed on the photoconductor 1 as described above. Send it out. As a result, the toner image on the photosensitive member 1 and the transfer paper P sent out by the registration roller pair 14 are brought into close contact with each other at the transfer nip. Then, it is electrostatically transferred onto the transfer paper P due to the influence of the transfer voltage.

A paper transport belt 12 is wound around the transfer roller 12a, and the paper transport belt 12 is stretched between the transfer roller 12a and the drive roller 12b, and moves endlessly counterclockwise in the drawing. Further, a fixing device 9 and a discharge roller pair 10 are sequentially disposed on the left side of the paper conveying belt 12. The transfer paper P on which the above-described toner image has been electrostatically transferred is fed onto the paper transport belt 12 and then enters the fixing device 9. The transfer paper P that has entered the fixing device 9 is subjected to heat treatment and pressure treatment. As a result, the toner is thermally melted under pressure and the toner image is fixed on the transfer paper P. Then, the transfer paper P is discharged from the fixing device 9 to the paper discharge tray 15 through the paper discharge roller pair 10.
The toner remaining on the photosensitive drum without being transferred is collected by the cleaning device 7.

The photosensitive member 1, the developing device 6, the charging device 2, the cleaning device 7 and the like disposed around the photosensitive member 1 may be configured as a process cartridge. This process cartridge is detachable from the printer body. Therefore, when the life of a component housed in the process cartridge comes to an end or maintenance is necessary, the process cartridge may be replaced, and the convenience is improved.
FIG. 2 is an enlarged configuration diagram of the cleaning device 7 shown in FIG. The cleaning device 7 includes a cleaning roller 71, a scraper member 73, and a transport unit 74. The cleaning roller 71 is brought into contact with the photoreceptor 1 to form a cleaning nip. The cleaning roller 71 is driven to rotate counterclockwise in the figure by driving means (not shown) so as to move in the same direction as the surface of the photoreceptor 1 at this nip. The plate-shaped scraper member 73 is disposed so that the edge at the tip thereof is brought into contact with the cleaning roller with a predetermined pressure. Further, the conveying means 74 is disposed below the scraper member 73 in the direction of gravity.

FIG. 3 is a schematic configuration diagram of the cleaning roller 71 shown in FIG. The cleaning roller 71 is provided with an electrode 201 formed of a conductive material and a surface layer 202 formed of an electret material on the surface of a cylindrical core material. The electrode 201 and the electret surface layer 202 have a combination of strips, and the electrode 201 and the electret surface layer 202 appear alternately in the roller rotation direction. By applying a positive voltage to the electrode 201, the surface of the cleaning roller 71 has a first region 71e having a positive potential extending in the axial direction as the center of the portion having the highest positive charge density, and a negative polarity. As the center of the portion having the highest charge density, second regions 71f having a negative potential in the axial direction are alternately formed (see FIG. 4).
As a result, a strong electric field is generated between the first region 71e and the second region 71f. By the electric field formed between these regions, the transfer residual toner charged to the positive or negative polarity on the surface of the photoreceptor can be attracted to the cleaning roller 71 by being attracted to the first region 71e or the second region 71f. It is also possible to change the electric field by arbitrarily controlling the voltage applied to the electrode 201, and it is possible to control according to the toner input amount, and the most efficient cleaning condition can be instantly created. It becomes possible.

In the present embodiment, the first region 71e having a positive potential and the second region 71f having a negative potential are provided in a straight line along the axis of the roller. It may be curved. Further, the first region 71e and the second region 71f may be arranged in a lattice shape, a staggered shape, or at random.
In this embodiment, a surface layer made of an electret material is directly provided on the surface of the core material. However, an elastic layer made of an elastic member such as foamed urethane rubber is formed on the surface of the core material. A surface layer made of an electret material may be formed on the surface of the layer. By providing the elastic layer, the cleaning roller 71 can be favorably bent and the cleaning nip can be widened.

  The electret material is a polymer material that is permanently electrically polarized. The electret material can be generally obtained by heating and cooling a polymer material with an electric field applied from the outside. The reason why such a characteristic is born is considered as follows. When a strong electric field is applied from the outside while the polymer material is heated, the ions constituting the polymer material, ions bound to the molecule, ions dispersed in the polymer material, and the like reappear along the electric field. They are arranged, or binding ions and dispersed ions move in the material and are unevenly distributed. When slowly cooled in such a state, the polymer material, the bound ions, and the dispersed ions cannot move and become an electret material that stably shows a non-uniform charge state. There are an extremely large number of polymer materials exhibiting such characteristics, which are general polymers. Typically, any of styrene, polyethylene, polyester, polyethylene terephthalate, and the like can be used as an electret material. In addition, electret properties are exhibited even when modifications such as fluorine and chloride are added. Since ions of molecular level polarization, bonding, or dispersion are important, strong electret properties can be expressed by implanting electrons or ions into the material from the outside during the creation of the electret material.

  As the negative electret material, a material obtained by adding a specific aminosilane compound to an amorphous fluororesin having very excellent electret properties is used. Although the detailed mechanism is still unknown, a large number of negative charges are arranged around the electrostatic charge by dispersing a positively charged low molecular weight compound having an amino group in the fluororesin, which is a negatively chargeable material. It is presumed that stable electret properties are expressed. This material has an excellent performance in which the surface potential hardly attenuates for one year or more in a normal temperature and humidity environment. Further, as the electretization method, treatment with an electret by so-called radio electret, in addition to the conventional corona discharge and direct current application with a sandwich electrode, is most desirable. This is because most of the surface charge is generated by corona discharge and direct current applied by sandwich electrodes, whereas in the radio electret, electrons penetrate deep into the resin and are held as space charges. As a result, it is possible to prevent charging stability for 3 years or more, prevention of attenuation in a high humidity environment, and deterioration of electret properties due to contact or friction. Further, by using a silane compound, the adhesiveness to the substrate is very poor with only the fluororesin, but there is an effect of improving this.

（式中、ｎは繰り返し単位数である。）

（式中、ＹはＮＨ_２または（ＣＨ_２）_ｊ−ＮＨ_２を示し、Ｒは（ＣＨ_２）_ｋＣＨ_３を示す。ｍは１または２、ｊおよびｋは１、２または３である。）
なお、本実施形態のエレクトレット材料の詳細な製造方法については、後述する。 In the present invention, as the negative electret material, a material containing an amorphous fluororesin and an aminosilane compound is used. As the amorphous fluororesin, those represented by the following general formula (1) are preferable, and both ends of the molecule are groups selected from CF ₃ , COOH and CONH—C ₃ H ₆ —Si (OC ₂ H ₅ ) _3. Is preferred. As an aminosilane compound, what is represented by following General formula (2) is preferable. In the present invention, the following amorphous fluororesin and the following aminosilane compound are preferably used in combination.

(In the formula, n is the number of repeating units.)

(In the formula, Y represents NH ₂ or (CH ₂ ) _j —NH ₂ , R represents (CH ₂ ) _k CH ₃ , m is 1 or 2, j and k are 1, 2 or 3. )
In addition, the detailed manufacturing method of the electret material of this embodiment is mentioned later.

  Next, the operation of the cleaning device 7 will be described in detail. When a print signal is input and an image forming operation is started, after the charging, writing, developing, and transferring steps, the transfer residual toner on the photosensitive member 1 is sent to a portion facing the cleaning device 7. In the transfer residual toner, in addition to the toner charged to the normal polarity (negative polarity) by being charged in the transfer step, the toner charged to the reverse polarity (positive polarity) or the non-charged toner is mixed. When the surface of the photoreceptor enters the cleaning nip region, negative transfer residual toner on the surface of the photoreceptor is between the first region 71e and the second region 71f on the surface of the cleaning roller 71 as shown in FIG. It is captured by the circumferential electric field formed in the cleaning roller. The negative transfer residual toner on the surface of the photoconductor moves under the influence of the electric field between the regions and moves between the photoconductor 1 and the cleaning roller 71 to the first region 71e having the positive potential and cleaning. It is electrostatically attracted to the first area 71e on the surface of the roller 71. On the other hand, the positive transfer residual toner on the surface of the photosensitive member moves while rolling between the photosensitive member 1 and the cleaning roller 71 to the second region 71f having a negative potential by the action of an electric field between the regions. The two regions 71f are electrostatically adsorbed. Further, the weakly charged transfer residual toner on the surface of the photosensitive member also rolls between the photosensitive member 1 and the cleaning roller 71 due to the action of a strong electric field between the regions, and frictionally charges to increase the charge amount to the first region 71e. Move and electrostatically attract to the cleaning roller 71. Further, the uncharged toner on the surface of the photosensitive member is frictionally charged before passing through the cleaning nip, and is electrostatically attracted to the cleaning roller 71. Thereby, the transfer residual toner on the surface of the photoreceptor is removed by the cleaning roller 71.

FIG. 5 is a view for explaining how the positive transfer residual toner electrostatically attracted to the second area 71 f on the surface of the cleaning roller 71 is removed by the scraper member 73. As shown in FIG. 5A, the positive transfer residual toner 104 electrostatically attracted to the second region 71 f on the surface of the cleaning roller 71 is blocked by the scraper member 73. As shown in FIG. 5B, the positive transfer residual toner 104 dammed up by the scraper member 73 relatively moves on the surface of the cleaning roller. As shown in FIG. 5C, when the positive transfer residual toner 104 dammed up by the scraper member 73 faces the first region 71e having the positive potential on the surface of the cleaning roller 71, the positive polarity The transfer residual toner 104 flies from the surface of the collection roller by a repulsive force and is detached from the cleaning roller 71.
Similarly, after the negative transfer residual toner 105 adhering to the first region 71e on the surface of the cleaning roller 71 is blocked by the scraper member 73, the toner moves relatively on the surface of the cleaning roller. Then, when facing the second region 71 e having a negative potential, it flies off the surface of the cleaning roller with a repulsive force and is detached from the cleaning roller 71. Thereby, the transfer residual toner is removed from the surface of the cleaning roller, and stable cleaning performance can be maintained.
The untransferred toner separated from the cleaning roller 71 falls onto the conveying means 74 (see FIG. 2), and is appropriately discharged out of the cleaning device 7 by the conveying means 74.

In addition, the scraper member 73 is preferably brought into contact with the cleaning roller 71 so that at least one of the scraper member 73 and the cleaning roller 71 is elastically deformed. For example, when the scraper member 73 and the cleaning roller 71 are brought into contact with the cleaning roller 71 without deformation, due to the swell of the scraper member 73 itself, the swell and eccentricity of the surface of the cleaning roller 71, etc., as shown in FIG. In addition, there may be a gap between the scraper member 73 and the surface of the cleaning roller 71. In such a case, the transfer residual toner adsorbed on the cleaning roller 71 may not be blocked by the scraper member 73 and may slip through the gap between the scraper member 73 and the cleaning roller 71.
For this reason, as shown in FIG. 6B, the hardness of the scraper member 73 is lowered and elastically deformed so as to contact the cleaning roller 71. As a result, even if the swell of the scraper member 73, the swell or eccentricity of the surface of the roller 71 occurs, the scraper member 73 is elastically deformed to absorb these fluctuations, and the adhesion between the cleaning roller 71 and the scraper member 73 is improved. Can be secured. Further, as shown in FIG. 6C, the same effect can be obtained even when the cleaning roller 71 is elastically deformed.

  Further, when the cleaning roller 71 has the same linear velocity as the photosensitive member 1, the contact position between the toner remaining on the photosensitive member and the cleaning roller 71 does not change until the cleaning roller 71 passes through the cleaning nip. Therefore, when the transfer residual toner on the surface of the photosensitive member at the entrance of the cleaning nip faces the portion having the highest charge density of the same polarity as the transfer residual toner on the surface of the cleaning roller, the transfer residual toner on the surface of the photosensitive member It is not affected by the electric field between them. Therefore, the untransferred toner is not subjected to an electrostatic force that moves to an area of a different polarity on the surface of the cleaning roller due to an electric field between the areas. As a result, there is a possibility that the cleaning roller 71 cannot be electrostatically attracted and cannot be removed from the surface of the photoreceptor. Therefore, in the present embodiment, the cleaning roller 71 is made faster or slower than the linear velocity of the photosensitive member 1 so as to provide a linear velocity difference with the photosensitive member 1.

FIG. 7 is a diagram for explaining how the positive transfer residual toner is attracted to the cleaning roller 71 when the linear velocity of the cleaning roller 71 is made slower than the linear velocity of the photosensitive member to provide a linear velocity difference. . As shown in FIG. 7A, when the positive transfer residual toner on the surface of the photosensitive member 1 faces the portion having the highest positive charge density on the surface of the cleaning roller at the entrance of the cleaning nip, FIG. As shown in FIG. 2, the transfer residual toner adhering to the surface of the photoconductor moves relatively upward on the surface of the cleaning roller 71 while rotating clockwise in the drawing. Then, the untransferred toner on the surface of the photosensitive member is statically moved to the second region 71f having the negative potential on the upper side due to the influence of the electric field formed between the first region 71e and the second region 71f on the surface of the cleaning roller. It is attracted electrically and adheres to the second region 71f (FIG. 7C). As a result, even if the polarity of the transfer residual toner on the surface of the photosensitive member at the entrance of the cleaning nip faces the portion with the highest charge density of the same polarity on the surface of the cleaning roller, the cleaning roller is surely kept until the cleaning nip passes 71 can be adsorbed.
7 illustrates an example in which the linear velocity of the cleaning roller 71 is slower than the linear velocity of the photosensitive member 1. However, the same applies when the linear velocity of the cleaning roller 71 is higher than the linear velocity of the photosensitive member 1. An effect can be obtained. In this case, the transfer residual toner relatively moves on the surface of the cleaning roller 71 downward in the figure, and is electrostatically attracted to the lower area in the figure.

Further, the transfer residual toner once electrostatically attracted to the cleaning roller 71 does not move relative to the surface of the cleaning roller due to a mechanical force due to the linear speed difference between the cleaning roller 71 and the photosensitive member 1. The mechanical force is weaker than the electrostatic adsorption force by the electrode. In the present embodiment, the mechanical force due to the difference in linear velocity is adjusted so as to be weaker than the electrostatic attraction force by the contact pressure of the cleaning roller 71 to the photosensitive member 1. Further, it is preferable to reduce the elasticity by providing an elastic layer on the cleaning roller 71 so that the cleaning nip width is not narrowed as a result of the contact pressure of the cleaning roller 71 with the photoreceptor 1 being lowered.
Further, a linear velocity difference between the photosensitive member 1 and the cleaning roller 71 so that the uncharged transfer residual toner on the photosensitive member is frictionally charged before it passes through the cleaning nip and can be electrostatically attracted to the cleaning roller 71, Set the cleaning nip width.

  If there is a slight linear velocity difference between the photosensitive member 1 and the cleaning roller 71, the transfer residual toner on the surface of the photosensitive member can be reliably affected by the electric field between the regions on the surface of the cleaning roller, and the transfer residual toner. It is possible to move to a region having a polarity different from the charged polarity of the toner and electrostatically attract the cleaning roller 71. However, in order to more reliably cause the transfer residual toner to be electrostatically attracted to the cleaning roller 71, the surface of the photoreceptor contacts the first region 71e and the second region 71f at least once while passing the cleaning nip. It is preferable. As a result, the transfer residual toner on the surface of the photosensitive member comes into contact with a region having a potential different from the charge polarity of the transfer residual toner until it passes through the cleaning nip. As a result, the transfer residual toner on the photoconductor can be electrostatically attracted to the cleaning roller 71 reliably.

The inter-region pitch between the first region 71e and the second region 71f on the surface of the cleaning roller is preferably set at least equal to or larger than the particle size of the toner. The smaller the pitch between the regions, the stronger the electric field between the regions and the stronger the force for electrostatically attracting the toner, which is preferable. However, as shown in FIG. 8A, when the inter-region pitch L1 is smaller than the particle diameter M of the toner, the toner on the photoreceptor is affected by the electric field between the plurality of regions. That is, due to the influence of the electric field X1 between the second region A located on the left side in FIG. 8A and the first region B located substantially in the center in the region of the cleaning roller surface facing the untransferred toner 106. The positive transfer residual toner is subjected to a force that moves electrostatically to the left in FIG. At the same time, the electric field between the second region C located on the right side in FIG. 8A and the first region B located substantially in the center of the cleaning roller surface region facing the transfer residual toner 106. Due to the influence of X2, a force that electrostatically moves to the right side in the figure acts on the positive transfer residual toner. As a result, the forces that move the transfer residual toner electrostatically cancel each other. Therefore, the force for electrostatically moving the toner is weakened. For this reason, the inter-region pitch L1 is preferably set to at least the particle size M of the toner, as shown in FIG. Thereby, the transfer residual toner 106 is only affected by the electric field X3 between one region, and the influences of the electric field do not cancel each other. Therefore, the untransferred toner 106 is moved by the electrostatic force that moves to the left in FIG. 8B generated by the electric field between the regions, and is attracted to the second region 71f.
In the present embodiment, toner having an average particle diameter of 5 to 10 μm is used. In this case, the inter-region pitch L1 is preferably at least 10 μm.

Further, as shown in FIG. 9, even if the inter-region pitch L1 is wide, the surface of the photoreceptor 1 is brought into contact with the first region 71e and the second region 71f at least once while passing the cleaning nip. It is conceivable to increase the cleaning nip width or increase the linear velocity difference between the photosensitive member 1 and the cleaning roller 71. However, when the nip width is increased or the difference in linear velocity between the photosensitive member 1 and the cleaning roller 71 in the cleaning nip is increased, the transfer residual toner is caused by the progress of abrasion or friction due to the frictional force between the photosensitive member 1 and the cleaning roller 71. Additives and the like fall off and the filming on the surface of the photoreceptor is accelerated.
In order to suppress such a problem, the linear velocity Vc of the cleaning roller 71 is preferably suppressed to 0.5 to 1.5 times the linear velocity Vd of the photoreceptor 1. In the cleaning nip, when the moving direction of the cleaning roller 71 moves in the opposite direction to the moving direction of the photosensitive member 1, the transfer is caused by the progress of friction or friction caused by the frictional force between the photosensitive member 1 and the cleaning roller 71 as described above. Since the residual toner additives may fall off and the filming on the surface of the photoconductor may be accelerated, the cleaning roller moves in the forward direction relative to the photoconductor in the cleaning nip. It is preferable to do this.

  Further, if the diameter of the cleaning roller 71 is increased, the width of the cleaning nip can be increased. However, if the diameter of the cleaning roller 71 is increased, the apparatus is increased in size. For this reason, in order to suppress the enlargement of the apparatus, the diameter of the cleaning roller is preferably 8 to 12 [mm], more preferably about 10 [mm]. When the diameter of the cleaning roller 71 is about 10 [mm], it is difficult to set the cleaning nip width N to 1 [mm] or more. Therefore, in this embodiment, the nip width is set to 1 [mm] or less and (Vc (linear speed of the cleaning roller) / Vd (linear speed of the photosensitive member)) of 0.5 to 1.5. Therefore, in the present embodiment, the condition that the inter-region pitch L1 is maximum is when the nip width N is 1 [mm] and (Vc / Vd) is 0.5 or 1.5.

  The time t required for the surface of the photoreceptor 1 to move from the cleaning nip entrance to the exit is t = N / vd. At this time t, the distance y that the cleaning roller 71 moves is Vc × t = (Vc / Vd) N. When the nip width N = 1 [mm] and (Vc / Vd) = 0.5, the moving distance y of the cleaning roller surface is 0.5 [mm]. That is, the surface of the cleaning roller moves by 0.5 [mm] while the surface of the photoconductor moves by 1 [mm] of the nip width. Therefore, if the inter-region pitch L1 is set to 0.5 [mm] or less, the surface of the photoreceptor can be brought into contact with the first region 71e and the second region 71e while passing through the cleaning nip. When (Vc / Vd) = 1.5, the surface of the cleaning roller 71 moves 1.5 [mm] while the surface of the photoconductor 1 moves with the nip width N = 1 [mm]. That is, while the photosensitive member surface passes through the cleaning nip, the cleaning roller surface advances 0.5 [mm] ahead. Therefore, also in this case, if the inter-region pitch L is set to 0.5 [mm] or less, the surface of the photoreceptor can be brought into contact with the first region 71e and the second region 71f while passing through the cleaning nip. .

Next, although manufacture of a cleaning roller is demonstrated in detail by Examples 1-3, a manufacturing method is not limited to these.
First, the manufacturing method of the cleaning roller of Example 1 will be described.
FIG. 10 is a diagram illustrating the method for manufacturing the cleaning roller of the first embodiment. First, a fluororesin represented by the general formula (1) having both ends at the COOH group and a weight average molecular weight of about 50000 is dissolved in perfluoroalcohol at a concentration of 5% by mass. Further, 3-aminopropyl (diethoxy) methylsilane is dissolved in this solution so as to have a ratio of 3% by mass with respect to the fluororesin, thereby obtaining a coating solution 1. On the other hand, a comb-like projection 621 is formed on a flat plate by fine processing such as electroforming, and the coating liquid 1 is applied to the flat portion of the surface of the projection 621 (FIG. 10A). A strip-shaped protrusion is stuck on the conductive sheet 50 so as to face the sheet 50, and the fluororesin solution 622 is transferred to the surface of the conductive sheet 50 (FIG. 10B). The conductive sheet is dried, the fluororesin is solidified, and a sheet in which the fluororesin is applied in a comb shape on the conductive sheet is produced (FIG. 10C). There is no particular restriction on the thickness of the fluororesin, but the thickness after drying is 10 μm or more in terms of preventing dielectric breakdown in the bulk and obtaining a sufficient charge density and preventing short-circuiting at the time of charge injection by the sandwich electrode described later. It is desirable that the thickness is 50 to 300 μm.
Next, as shown in FIG. 11, the sheet 50 thus obtained is sandwiched between a plate-like first electrode 61 connected to the ground and a plate-like second electrode 62 connected to the power source. . The second electrode 62 is connected to a DC high voltage power supply 64 through a negative electrode portion 63 for applying a negative bias.

A negative voltage of −5 kV is applied to the second electrode 62 by the DC high-voltage power supply 64 and the sheet material 50 is heated to 120 ° C. Thereby, negative electric charge injection is performed to the fluororesin formed in strip shape, and electret property is expressed. Next, when the sheet material is removed to room temperature, as shown in FIG. 10 (c), electrets in which the first regions where the conductive sheets are exposed and the second polarity having a negative potential are arranged alternately. A sheet material is obtained. Separately from this, when a 20 mm square fluororesin was electreted using the same method and the surface charge density was calculated from the surface potential, it was confirmed that the charge density was as high as 1.2 mC / m ² .
And as shown in FIG.10 (d), by winding the sheet material of the obtained electret material around the cylindrical core material 71b, the 1st area | region which has electroconductivity, and the 1st area | region which has a negative potential. A cleaning roller in which two polarities are alternately arranged can be obtained.
Using the cleaning roller thus obtained, a potential of +350 V was applied to the first region serving as an electrode to clean the transfer residual toner on the photosensitive member. As a result, the toner could be electrostatically adsorbed to the cleaning roller. Very good toner removal performance was obtained.
In FIG. 10D, although drawn roughly, both ends of the sheet material made of electret material are butted with high accuracy and wound around the core material so that the joints do not hinder rotation. Further, when the sheet material is wound around the core material so that the end portions of the sheet material are overlapped, the stacking order is the rotation direction of the cleaning roller 71 so that the scraper member 73 contacting the cleaning roller does not peel off the overlapped portion. Overlapping edges so that they are in order.

Further, it is possible to prevent the cleaning roller surface from having a joint or an overlapping portion. In order not to have joints or overlapping portions, a fluororesin is applied to a seamless conductive roller obtained by injection molding or the like while being rotated by the transfer method described above. The electretization by charge injection can be performed in the same manner as described above.
In addition, by changing the shape of the protrusion used at the time of transfer, various area patterns such as a lattice shape and a curved shape can be formed on the surface of the cleaning roller.

Next, a method for manufacturing the cleaning roller of Example 2 will be described.
FIG. 11 is a diagram illustrating a method for manufacturing the cleaning roller 71 according to the second embodiment. Similarly to Example 1, a sheet in which a fluororesin is applied in a comb shape on a conductive sheet is prepared. In Example 2, there is no limitation on the thickness of the fluororesin because no short circuit occurs during electretization, but here again, in order to prevent dielectric breakdown in the bulk and increase the surface charge, the thickness is 10 μm or more. It is desirable that the thickness is 50 to 300 μm.
The sheet 50 thus obtained is irradiated with an electron beam by an area beam type electron beam irradiation apparatus (NHVCorp.Curetron) to inject charges into the resin. The test was carried out under the conditions of an acceleration voltage of 200 kV, a current of 20 mA, a dose of 15 kGy / Pass, and 3 Pass. The conductive sheet portion is slightly charged with static electricity, but does not have electret properties. Only the fluororesin portion is strongly negatively charged and can be permanently charged. Apart from this, using a similar method, electrifying a 20 mm square fluororesin by electron beam irradiation under the same conditions and calculating the surface charge density from the surface potential yields a high charge density of 2.1 mC / m ^2. It was confirmed. Despite the extremely high charge, neither dielectric breakdown from the air interface nor internal dielectric breakdown occurred.

The strip-shaped electret sheet thus manufactured is wound around a cylindrical core material in the same manner as in Example 1, thereby having a first region having conductivity and a negative potential. A cleaning roller in which the second polarity is alternately arranged can be obtained. As in Example 1, when a potential of +350 V was applied to the first region serving as an electrode and the transfer residual toner on the photoconductor was cleaned, the toner could be completely electrostatically adsorbed to the cleaning roller, which was extremely excellent. Toner removal performance was obtained.
Compared with the manufacturing method of Example 1, since there is no operation to apply a high voltage near the conductive sheet, it is safe, and since many charges can be injected as space charges, the cleaning property can be improved. For the same reason, the pitch between the regions can be greatly reduced as compared with the case where the electret is formed by the sandwich electrode. As a result, the electric field between the regions can be further increased, and the transfer residual toner on the photoreceptor can be electrostatically adsorbed to the cleaning roller.

Next, a method for manufacturing the cleaning roller of Example 3 will be described.
FIG. 12 is a diagram for explaining a method of manufacturing the cleaning roller according to the third embodiment. Similarly to Example 1, a sheet in which a fluororesin is applied in a strip shape on a conductive sheet is prepared. In Example 3, there is no limitation on the thickness of the fluororesin because no short circuit occurs during electretization, but here again, in order to prevent dielectric breakdown in the bulk and increase the surface charge, the thickness is 10 μm or more. It is desirable that the thickness is 50 to 300 μm.
First, as shown in FIG. 12, the surface on which the fluororesin is applied on the electrode 87 connected to the ground is placed on the opposite side of the electrode. Next, as shown in FIG. 12, the sheet is uniformly charged using a corona charger. The voltage applied to the corona charger was set to -5.5 kV, and the grid voltage was set to -500V. In this embodiment, corona discharge using a tungsten wire is used. However, a needle electrode may be used as long as similar corona discharge occurs.
Thereby, as shown in FIG. 10C, a sheet material in which first conductive regions having a predetermined width on the surface and linear second regions having a negative potential appear alternately. It is formed. Next, as shown in FIG. 10 (d), the first region having conductivity and the second polarity having a negative potential are alternated by winding the sheet material around a cylindrical core material 71b. The cleaning rollers 71 (see FIG. 9) arranged in the above can be obtained. Here again, as in Example 1, when a potential of +350 V was applied to the first region serving as an electrode and the transfer residual toner on the photoconductor was cleaned, the toner could be completely electrostatically adsorbed to the cleaning roller. Excellent toner removal performance was obtained.

Next, the manufacturing method of the cleaning roller of Example 4 will be described.
In Example 4, all were produced under the same conditions as in Example 2 except that both ends of the amorphous fluororesin used (general formula (1)) were replaced with CF ₃ groups. Similar to the result of Example 2, the conductive sheet portion is slightly charged with static electricity but does not have electret properties. Only the fluororesin portion is strongly negatively charged and can be permanently charged. Apart from this, using a similar method, electrifying a 20 mm square fluororesin by electron beam irradiation under the same conditions and calculating the surface charge density from the surface potential yields a high charge density of 1.4 mC / m ^2. It was confirmed. Despite the extremely high charge, neither dielectric breakdown from the air interface nor internal dielectric breakdown occurred.

  The strip-shaped electret sheet thus manufactured is wound around a cylindrical core material in the same manner as in Example 1, thereby having a first region having conductivity and a negative potential. A cleaning roller in which the second polarity is alternately arranged can be obtained. As in Example 1, a potential of +350 V was applied to the first region serving as an electrode to clean the transfer residual toner on the photosensitive member. As a result, the toner could be completely electrostatically adsorbed to the cleaning roller, which was excellent. Toner removal performance was obtained.

Next, a method for manufacturing the cleaning roller of Example 5 will be described.
In Example 5, except for changing the both ends of the amorphous fluorine resin used (the general formula (1)) to _{CONH-C 3 H 6 -Si (} OC 2 H 5) 3 groups, the same as in Example 2 It was produced under the conditions of Similar to the result of Example 2, the conductive sheet portion is slightly charged with static electricity but does not have electret properties. Only the fluororesin portion is strongly negatively charged and can be permanently charged. Apart from this, using the same technique, electretizing a 20 mm square fluororesin by electron beam irradiation under the same conditions and calculating the surface charge density from the surface potential yields a high charge density of 1.9 mC / m ^2. It was confirmed. Despite the extremely high charge, neither dielectric breakdown from the air interface nor internal dielectric breakdown occurred.

  The strip-shaped electret sheet thus manufactured is wound around a cylindrical core material in the same manner as in Example 1, thereby having a first region having conductivity and a negative potential. A cleaning roller in which the second polarity is alternately arranged can be obtained. As in Example 1, when a potential of +350 V was applied to the first region serving as an electrode and the transfer residual toner on the photoconductor was cleaned, the toner could be completely electrostatically adsorbed to the cleaning roller, which was extremely excellent. Toner removal performance was obtained.

Next, a toner that is preferably used in the image forming apparatus of the present embodiment will be described. In order to obtain a high-definition image, it is preferable that the particle size distribution of small particles is sharp. With a toner having a small particle size and a narrow particle size distribution, the toner charge amount distribution is uniform, a high-quality image with little background fogging can be obtained, and the transfer rate can be increased.
The toner shape factor SF-1 is preferably in the range of 100 to 150. Here, the shape factor SF-1 is a numerical value indicating the ratio of the roundness of the shape of the spherical material, and the square of the maximum length MXLNG of the elliptical shape formed by projecting the spherical material on a two-dimensional plane is defined as a graphic area AREA. Divided by and multiplied by 100π / 4.
That is, it is defined by the following equation (1).
SF-1 = {(MXLNG) ² / AREA} × (100π / 4) (1)

  When the value of SF-1 is 100, the shape of the toner becomes a true sphere, and becomes larger as the value of SF-1 increases. In general, when the shape of the toner is close to a sphere, the contact state between the toner and the toner or the toner and the photoconductor becomes point contact, so that the adsorption force between the toners is weakened and the fluidity is increased. The adsorption force between the toner and the photosensitive member is also weakened, and the transfer rate is increased. Therefore, the amount of toner removed by the cleaning device can be reduced. Accordingly, it is possible to extend the life of the cleaning device by using toner having a high degree of circularity with a shape factor SF-1 in the range of 100 to 150.

Further, the toner used in this embodiment is prepared by the chemical synthesis method as described below. That is, a binder resin containing a modified polyester resin that can be urea-bonded in an organic solvent, a toner composition containing a colorant is dissolved or dispersed to form particles in an aqueous medium and a polyaddition reaction. It is obtained by removing the solvent from the dispersion, washing and drying. In addition, as a chemical synthesis method for obtaining a so-called spherical toner by increasing the average circularity, a known emulsion polymerization method, suspension polymerization method, dispersion polymerization method or the like may be used in addition to the above-described method. A toner obtained by spheroidizing treatment by heat treatment may be used.
In this embodiment, the cleaning device of the present invention is applied to a monochrome image forming apparatus having one process cartridge, but the present invention is not limited to this. For example, the present invention can be applied to a color image forming apparatus in which four process cartridges of magenta, cyan, yellow, and black are arranged side by side to constitute a tandem image forming unit.

  Further, the present invention can be applied to an intermediate transfer type image forming apparatus that transfers a toner image on a photosensitive member to an intermediate transfer member and transfers the toner image on the intermediate transfer member to a transfer sheet. At this time, the cleaning device of the present invention can be applied not only as a cleaning device for cleaning the transfer residual toner attached on the photosensitive member but also as an intermediate transfer member cleaning device for cleaning the transfer residual toner attached on the intermediate transfer belt. . As the intermediate transfer member, in addition to a belt-shaped intermediate transfer belt, a drum-shaped intermediate transfer drum or the like can be used. The electrical characteristics (volume resistivity, surface resistivity, etc.), thickness, structure (single layer, double layer, multiple layers), material, material, etc. of the intermediate transfer member are appropriate depending on the imaging conditions. Can be selected and employed.

In this embodiment, the cleaning roller is brought into contact with the photoconductor, but the cleaning roller may be disposed close to the photoconductor. Also in this case, the transfer residual toner on the surface of the photosensitive member is changed to the charge polarity of the transfer residual toner by the electric field between the first region having a positive potential on the surface of the cleaning roller and the second region having a negative potential. Attracts to the reverse polarity region. The transfer residual toner attracted by the influence of the electric field between the regions moves while rolling on the surface of the photosensitive member, and is adsorbed to a region having a polarity opposite to the charged polarity of the transfer residual toner. Thereby, the positive transfer residual toner and the negative transfer residual toner can be electrostatically adsorbed by one roller.
In the above description, the cleaning device that removes transfer residual toner attached to an image carrier such as an intermediate transfer member or a photosensitive member has been described. However, the present invention is not limited to this. For example, the present invention can also be applied to a cleaning device that removes positively charged dust and negatively charged dust attached to a floor, a desk, glass, or the like as an object to be cleaned.

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Charging device 2a Charging roller 3 Exposure device 4 Paper feeding cassette 4a Paper feeding roller 5 Transfer device 6 Developing device 7 Cleaning device 9 Fixing device 10 Paper discharge roller pair 12 Paper transport belt 12a Transfer roller 12b Drive roller 13 Transport roller Pair 14 Registration roller pair 15 Discharge tray 50 Conductive sheet 61 First electrode 62 Second electrode 621 Comb-like projection 622 Fluorine resin solution 623 Fluorine resin 63 Negative electrode portion 64 DC high voltage power supply 71 Cleaning roller 71b Core material 71e First area 71f having a positive potential 72f Second area 73 having a negative potential Scraper member 74 Conveying means 101 Photoreceptor 102 Cleaning blade 103 Spherical toner 104 Positive transfer residual toner 105 Negative transfer residual toner 106 Transfer residual toner 110 Electrostatic brush cleaning Device 111 Conductive brush roller 112 Flicker 113 Power source 120 Cleaning device 121 First conductive brush roller 122 Second conductive brush roller 123 Toner recovery device 124 Toner recovery device 131 Power source 132 Power source 201 Electrode 202 Surface layer A Second region B Second 1 region C 1st region L Laser beam L1 Inter-region pitch M Toner particle size P Transfer paper X1, X2, X3 Electric field

JP 2005-157374 A JP 2007-199639 A

Claims (13)

In a cleaning device provided with a cleaning roller that comes close to or abuts on the object to be cleaned and electrostatically removes the charged fine powder on the surface of the object to be cleaned.
The cleaning roller surface includes a first region having a positive potential and a second region having a negative potential,
The second region is constituted by a negative electret material containing an amorphous fluororesin and an aminosilane compound. The cleaning device according to claim 1,
The cleaning apparatus, wherein the first region having a positive potential is configured by an electrode having a variable potential. The cleaning device according to claim 1 or 2,
The amorphous fluororesin is a fluororesin represented by the following general formula (1).

(In the formula, n is the number of repeating units.) The cleaning device according to any one of claims 1 to 3,
The cleaning apparatus, wherein the aminosilane compound is an aminosilane compound represented by the following general formula (2).

(In the formula, Y represents NH ₂ or (CH ₂ ) _j —NH ₂ , R represents (CH ₂ ) _k CH ₃ , m is 1 or 2, j and k are 1, 2 or 3. ) The cleaning device according to any one of claims 1 to 4,
The cleaning device characterized in that the negative electret material in the second region has been subjected to permanent charging treatment by electron beam irradiation. The cleaning device according to any one of claims 1 to 5,
A scraper member that contacts the cleaning roller, dams up the charged fine powder adhering to the cleaning roller, and opposes the charged fine powder to a region of a polarity different from the charged polarity of the charged fine powder on the surface of the cleaning roller; A cleaning device characterized. The cleaning device according to claim 6.
The cleaning apparatus, wherein the scraper member is brought into contact with the cleaning roller so that one of the scraper member and the cleaning roller is elastically deformed. The cleaning device according to any one of claims 1 to 7,
A cleaning apparatus, characterized in that a linear velocity difference is generated between the object to be cleaned and the cleaning roller in a region where the object to be cleaned and the cleaning roller are opposed to each other. The cleaning device according to claim 8, wherein
The first and second regions and the surface of the object to be cleaned are in contact with each other at least once while the surface of the object to be cleaned passes through the region facing the cleaning roller. Cleaning device. The cleaning device according to any one of claims 1 to 9,
The cleaning device, wherein the first region and the second region are arranged at a pitch equal to or greater than an average particle diameter of the charged fine powder. The cleaning device according to any one of claims 1 to 10,
The cleaning device, wherein the first region and the second region are formed on the surface of the cleaning roller in a comb-shaped pattern. An image carrier, a charging device for charging the image carrier, a latent image forming device for forming an electrostatic latent image on the image carrier, and a toner attached to the electrostatic latent image on the image carrier. In an image forming apparatus comprising: a developing device that visualizes; a transfer device that transfers a toner image on the image carrier to a transfer material; and a cleaning device that cleans the image carrier.
An image forming apparatus using the cleaning device according to claim 1 as the cleaning device. The image forming apparatus according to claim 12.
An image forming apparatus comprising: a toner having a shape factor SF-1 in the range of 100 to 150 as a toner for forming a toner image on the image carrier.

Images