JPH0310276A - Surface processing device for electrophotographic photosensitive body - Google Patents

Abstract

PURPOSE:To prevent uneveness in roughening caused by the contamination of a pressre roller and to obtain a lublicant photosensitive body surface by providing the pressure roller which makes an abrasive abut on the photosensitive body with a cleaning member. CONSTITUTION:The electrophotographic photosensitive body 1 is rotated clock wise or counterclockwise. While, a film type abrasive 2 is moved from a feeding roller 3 to a take-up roller 5 in the direction of an arrow A through the pressure roller made of rubber 4 which is in press-contact with the electrophotographic photosensitive body. At this time, the film type abrasive 2 rubbs the surface of the electrophotographic photosensitive body 1 at the position of the pressure roller 4. Then, by providing the pressure roller 4 with a pressure roller cleaning member 6, such debrises as dust sticking on the surface of the pressure roller 4 is removed and roughening is performed. Thus, uneveness in roughening caused by the contamination of the pressure roller is prevented and the photosensitive body with high lubricity is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a surface treatment apparatus for electrophotographic photoreceptors, and more particularly, to electrophotography for obtaining organic electrophotographic photoreceptors with good cleaning properties and image characteristics. The present invention relates to a surface roughening treatment device for a photoreceptor.

[Prior Art] Generally, in an electrophotographic process, an electrophotographic photoreceptor is repeatedly subjected to a cycle consisting of at least the steps of charging, image exposure, development, transfer, and cleaning. Especially after the transfer process. The cleaning process that removes residual toner on the photoreceptor is an important step to always obtain clear copy images.

Two conventional methods are used for this cleaning. The first method is to press a rubber plate-shaped member called a cleaning blade onto the photoconductor to eliminate the gap between the photoconductor and the cleaning blade, thereby preventing toner from slipping through and scraping off the remaining toner. be. FIG. 2 is a schematic cross-sectional view showing a typical example of a cleaning device using such a leaning blade.
A cleaning device 7 is placed close to a cylindrical photoconductor 8 rotating in the direction of arrow A, and one edge of one end of a cleaning blade 9 attached to the cleaning device is connected to the surface of the photoconductor 8. Then, scrape off the remaining 1-1 toner by pressing the photoconductor in one direction against the rotating direction of the photoconductor or in the forward direction (not shown). (It is known that it is). The second method is to wipe or knock off the remaining toner by rotating the roller of the fur brush so that it comes into contact with the surface of the photoreceptor. Among these methods, rubber blades are cheaper and easier to design, so cleaning using cleaning blades is currently the mainstream. Especially when performing natural color development, natural colors are produced by layering the three primary colors of magenta, cyan, and yellow, or even four colors including black!・The machine used by Gnar is the normal 1
color development, and therefore it is best to use a cleaning method in which a rubber blade is pressed against the photoreceptor.

However, cleaning blades that exhibit excellent cleaning properties have a large frictional force with the photoreceptor, so
There was a drawback that the cleaning blade was difficult to reverse. This reversal of the cleaning blade means that the cleaning blade 9a in the direction of the counter force shown in FIG. It is a phenomenon.

This phenomenon of the cleaning blade reversing is due to the fact that the surface of the photoconductor is hardened and scraped in order to extend the life of the photoconductor.
If t < , Cjv becomes 41 days easier. Additionally, when toner particle size is made uniform and minute toner particles are removed to improve image quality, toner may enter the gap between the cleaning blade and the surface of the photoreceptor. Since the lubricity caused by cleaning is weakened, the cleaning blade is more likely to turn over.

In addition, when performing natural color development, toner of magenta, cyan, and yellow or four colors including black is used three or four times to produce one image.
Because development is performed twice, the load on the cleaning blade increases, causing the cleaning blade to turn over,
Furthermore, a chip 1U at the edge portion is likely to occur.

In addition, when the surface layer of the photoreceptor is made of an organic material, the frictional resistance between the cleaning blade and the photoreceptor surface increases compared to an airless surface. is more likely to occur.

Therefore, in Japanese Patent Application No. 62-256769, the applicant previously proposed that the surface of the photoreceptor be roughened in advance so as to avoid deterioration in image quality by cleaning the cleaning blade by inverting the cleaning blade, chipping the blade edge, etc. We proposed a method to prevent defects. The roughening state of the photoreceptor surface is expressed by the 10-point average roughness (R, 1) measurement method defined by JrS standard BO601, and the maximum value, average value, and minimum value are preferably 0.3 to 0.3. It is within the range of 5.0 ILm, more preferably within the range of 0.3 to 2.0 LLm.If the maximum value is 5.0 μmJ: If the value is large, streaks will appear on the image as image defects. Furthermore, if the minimum value is smaller than 0.3 LLm, the friction between the cleaning blade and the photoreceptor surface is hardly alleviated in some areas, and the effect of roughening the photoreceptor surface is not recognized1. .The maximum value, average value and minimum value above are 0
, 3-5. If it is within the range of ( ) μm, the contact area between the photoreceptor surface and the cleaning blade is reduced, and ]
・Those with minute particle size contained in the toner (Habo 5
(μm or less) or scrapes (less than 1 μm) on the surface of the photoconductor that have been scraped off due to use can fit into the gap between the photoconductor surface and the cleaning blade, making it easier to provide lubricity. Therefore, it is possible to prevent cleaning failures due to inversion of the cleaning blade, etc.

On the other hand, as a method for roughening the surface of a photoreceptor, there is
J: Mechanical polishing methods such as sandblasting using brushes and abrasive materials as described in JP-A-3-92133 and JP-A-57-94772;
As described in JP-A No. 53-92133, the surface is made into a saucer-like shape under drying conditions during coating, or exposed to a solvent. There is a method of adding roughening powder particles to the surface layer and coating it to make the surface rough. Of these, PA
The mechanical polishing method is most preferable because it increases the lubricity between the cleaning defect and the surface of the photoreceptor.

This is because the scraping of the surface of the photoreceptor caused by mechanical polishing acts as a lubricant.

Further, among the 8a area polishing methods, a method using a film-like abrasive material is preferable. The reason for this is that in the case of the Sandplus 1-method, etc., the abrasive material is easily embedded in the organic electrophotographic photoreceptor, causing pinholes and deteriorating the electrophotographic properties, whereas the film This is because in the case of abrasive materials, there is almost no embedding.

[Problems to be Solved by the Invention] However, in the conventional mechanical polishing method in which the surface of the photoreceptor is pressure-polished with an abrasive material to make the surface rough, foreign matter such as dust particles attached to the back surface of the abrasive material is removed by polishing. The surface of the pressure roller that brings the material into contact with the photoreceptor gradually becomes dirty, and as a result, the ability of the pressure roller to press the material evenly is impaired.
There was a drawback that the surface was not evenly roughened.

Therefore, an object of the present invention is to obtain an organic electrophotographic photoreceptor with a uniformly roughened surface, which can prevent poor cleaning and scratch patterns on images due to reversal of the cleaning blade, loss of edges, etc. An object of the present invention is to provide a surface treatment device.

[Means for Solving the Problems] According to the present invention, in an apparatus for roughening the surface of an electrophotographic photoreceptor with a film-like abrasive material, the apparatus includes a device for bringing the abrasive material into contact with the photoreceptor. There is provided a surface treatment apparatus for an electrophotographic photoreceptor, characterized in that a pressing roller is provided, and the pressing roller is equipped with a cleaning member.

The device of the present invention includes a cleaning member on the presser roller, and removes foreign matter adhering to the presser roller.
10-point average surface roughness (R2) defined in S standard BO601
) and its maximum value, average value, and minimum value c
A uniform rough surface condition is obtained in which the maximum surface roughness, average surface roughness, and minimum surface roughness (hereinafter referred to as maximum surface roughness, average surface roughness, and minimum surface roughness, respectively) are all within the range of 0.3 to 5.0 ILm, and cleaning defects are prevented. be.

An example of a surface treatment apparatus for an electrophotographic photoreceptor according to the present invention is shown in FIG. 1 as a schematic cross-sectional view.

In FIG. 1, ■ is an electrophotographic photoreceptor, 2 is a film-like abrasive material, and 3 and 5 are a delivery roller and a winding roller for the abrasive material 2, respectively. Reference numeral 4 denotes a pressing roller for bringing the abrasive material 2 into contact with the photoreceptor 1. Reference numeral 6 denotes a cleaning member provided on the pressing roller 4.

Rotate the electrophotographic photoreceptor 1 clockwise or counterclockwise. On the other hand, a rubber presser roller 4 is in pressure contact with the electrophotographic photoreceptor from a roller 3 that feeds the film-like abrasive material 2.
It is moved to the winding roller 5 in the direction of arrow A. At this time, the film-like abrasive material 2 is
The surface of the electrophotographic photoreceptor 1 is rubbed at the position. In the present invention, by providing the press roller cleaning member 6 on the press roller 4, the surface of the press roller 4 is roughened while removing foreign matter such as dust attached to the surface.

The presser roller cleaning member provided in the device of the present invention may be any one that does not damage the presser roller.
, for example, a rubber blade (forward direction or counter direction), web, cloth, fur brush, sponge, etc. Further, if a cleaning liquid such as water or ethyl alcohol that does not harm the photoreceptor is used in combination, the cleaning effect will be even more effective.

Further, as the film-like abrasive material used in the apparatus of the present invention, for example, aluminum oxide, silicon carbide,
Examples include those in which fine particles of chromium oxide, diamond, etc. are coated and fixed on a film such as polyester.

The organic electrophotographic photoreceptor treated by the surface treatment apparatus of the present invention has an organic photosensitive layer 11 laminated on a conductive support lO, as shown in its cross section in FIG. 11 preferably includes a charge generation layer 12 and a charge transport layer 1
This is a laminated photosensitive layer with three functionally separated layers.

As a conductive support JO, it can be coated with a metal such as aluminum, aluminum alloy, stainless steel, a conductive material, or a suitable binder. ! Any conventionally known material can be used, such as a metal provided with a thin layer, or a drum-shaped or sheet-shaped material made of electrically conductive treated plastic or paper.

The charge generation layer 12 contains a charge generation substance such as an azo pigment, a quinone pigment, a gynocyanine pigment, a perylene pigment, an indigo pigment, or a phthalocyanine pigment, and a binding agent such as polyvinyl butyral, polystyrene, acrylic resin, polyester, polyvinyl acetate, or polycarbonate. It can be formed by being dispersed in a resin, or it can also be formed as a vapor deposited film using a vacuum evaporation device. The preferred film thickness is 0
．． It is 01 to 3 μm.

The charge transport layer 13 contains a charge transport material such as a styryl compound, a hydrazone compound, a triarylamine compound, a carbazole compound, an oxazole compound, or a pyrazoline compound, or a charge transport material such as a polyarylate, polystyrene, acrylic resin, polyester, or polycarbonate. It can be formed by being dispersed in a binder resin. The preferred film thickness is 10 to 30 μm.

1 In addition, as a structure of the photosensitive layer 11, the charge generation layer 12 may be formed on the charge transport layer 13, and furthermore, the photosensitive layer 11 may be
may be a single layer type in which the charge generating substance and the charge transporting substance described above are contained in the same layer.

Furthermore, an intermediate layer such as an undercoat layer may be provided between the conductive support 10 and the photosensitive layer 11 in order to improve adhesion and barrier properties.

The organic electrophotographic photoreceptor whose surface has been roughened by the method of the present invention is used in an electrophotographic process having a cleaning means using a rubber blade brought into contact with the photoreceptor in one counter direction.

[Example] The present invention will be explained below using examples.

Example 1 An aluminum cylinder support rod of 80φ
) Quaternary nylon copolymer) 5% methanol solution was applied by dip coating to provide a 1 part m thick undercoat layer.

2 Next, 10 parts of a disazo pigment having the following structural formula (parts by weight, the same applies hereinafter), polyvinyl butyral (degree of butyralization 68%,
5 parts (number average molecular weight 2'0000) and 50 parts of cyclohexanone were dispersed for 20 hours in a sand mill using 1φ glass beads. Add 70 to 1 methyl ethyl ketone to this dispersion.
Add 20 (appropriate) parts and coat on the undercoat layer to a film thickness of 0.1
A charge generation layer of .mu.m was formed.

Next, 10 parts of bisphenol Z type polycarbonate (viscosity average molecular weight 30,000) and 10 parts of a hydrazone compound of the following structural formula were mixed with monochlorobene C2H,5\
7◎ NO忰°""-")4 was dissolved in 6S part, and this solution was dip-coated on the charge generation layer 2 to form a charge transport layer with a thickness of 18 μm. The average surface roughness of this photoreceptor was 0.0 μm.

The surfaces of 1,000 photoreceptors prepared by the above method were all polished for 20 seconds using an apparatus shown in FIG. 1 having an abrasive material with a film grain size of 5.0 μm. At this time, a rubber blade was used as the pressing roller cleaning member and brought into contact with the pressing roller in the forward direction. In addition, the rotation speed of the pressing roller matches the feeding speed of the film-like abrasive material, and the speed is 70.0 mm.
/minute. Among the photoreceptors that underwent this surface polishing,
When the surface roughness of the first and last treated samples was measured, the average, minimum, and maximum surface roughness were 0.99 gm, 1.0 μm, 0.7 LLm, 0.8 gm, and 1.2, respectively.
Bm and 1.2jLm were almost identical. In addition, both photoreceptors were installed in an electrophotographic device (NP-3525, manufactured by Canon) having charging, image exposure, development, transfer, and cleaning with a rubber blade (linear pressure of 11.0 g/cml), and repeated image output evaluations were performed. When I did it,
No problems occurred until 100,000 copies were printed. The results are shown in Table 1.

Example 2 1000 photoreceptors prepared in the same manner as in Example 1 were treated in the same manner as in Example 1 using the same surface treatment apparatus as in Example I, except that a web soaked in alcohol was used as a pressing roller cleaning member. The surface was polished by 6Ji. When we measured the surface roughness of the first and last processed photoreceptors, the rF-average, minimum, and maximum surface roughness were all 0.
．． 9LLm and 0. ! 1μm, 0.7μm and o, 8μm,
They were almost the same as 1.2 μm and 1.2 μm. Both of these photoreceptors were incorporated into the same electrophotographic apparatus as in Example 1, and image output evaluations were repeatedly performed, and no problems occurred in either case up to 100,000 copies. The results are shown in Table 1.

Comparative Example 1 When a similar experiment was conducted using the same apparatus and photoreceptor as in Example 1 except that the photoreceptor was not polished, the reversal of the rotating cleaning blade for 10 images repeatedly occurred and the apparatus stopped working. 5 It was. The results are shown in Table 1.

Comparative Example 2 1000 photoreceptors coated in the same manner as in Example 1 were subjected to surface polishing under the same conditions as in Example 1 except that the pressing roller cleaning member 6 was not provided. When we measured the surface roughness of the first and last treated samples, we found that the average
The minimum and maximum surface roughness is 10 μm for the first treated surface.
,0. , +3 μm.

12 μm, and the last processed one was 1.3 μm.

[1,2+Lm, 5.21.1 m. When both photoreceptors were incorporated into an electrophotographic device similar to Example 1 and image output was evaluated, the former had no problems up to 100,000 copies, but the latter had image defects such as scratch patterns from the beginning of image output. Furthermore, after 30 sheets were rotated and images were produced, the blade reversed due to shallow surface roughness of the photoreceptor, causing the device to stop operating.1 The results are shown in Table 1.

6. Second, as shown in Example 1.2 and Comparative Examples 1 and 2, in roughening the surface of the photoreceptor, a cleaning member is provided on the pressing roller that brings the abrasive material into contact with the photoreceptor. In addition, it is possible to prevent uneven surface roughening due to dirt on the presser roller, and to obtain a photoreceptor surface with lubricity.

- As explained above, in the electrophotographic process using a cleaning means using a rubber blade, the surface of the photoreceptor is roughened and polished to prevent the cleaning blade from turning over or chipping the edges due to friction between the cleaning blade and the photoreceptor surface. However, there was a risk that the surface of the photoreceptor would be unevenly roughened due to dirt on the pressure roller that brings the abrasive material into contact with the photoreceptor. but,
According to the apparatus of the present invention, it is possible to produce a photoreceptor that is free from such problems, that is, has excellent lubricity due to its uniformly rough surface.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing an example of the surface treatment apparatus of the present invention. 1. FIG. 2 is a schematic sectional view of a cleaning device using a cleaning blade. FIG. 3 is a sectional view showing an example of an electrophotographic photoreceptor treated by the surface treatment apparatus of the present invention. 1 is an organic electrophotographic photoreceptor, 2 is a film strip abrasive material, 3 is a delivery roller, 4 is a press roller 5 is a take-up roller, 6 is a press roller cleaning member, 7 is a cleaning device, 8 is a photoreceptor, 9 is a cleaning A blade, 10 is a conductive support, 11 is a photosensitive layer, 12 is a charge generation layer, and 13 is a charge transport layer.

Claims (1)

[Claims] 1. In an apparatus for roughening the surface of an electrophotographic photoreceptor with a film-like abrasive material, the apparatus is provided with a pressing roller for bringing the abrasive material into contact with the photoreceptor, and the pressing roller is connected to a cleaning member. A surface treatment device for an electrophotographic photoreceptor, comprising: