JP6938427B2 - Manufacturing method of electrophotographic photosensitive member and electrophotographic photosensitive member and image forming apparatus - Google Patents

Description

The present invention relates to a method for producing an electrophotographic photosensitive member, an electrophotographic photosensitive member obtained thereby, and an image forming apparatus.

The electrophotographic photosensitive member used in the image forming apparatus, for example, prevents charge injection on the outer surface (also referred to as the outermost surface) which is the outer peripheral surface of a cylindrical substrate entirely made of an aluminum (Al) -based material. It has a structure in which a surface layer composed of a layer, a photoconductive layer, a surface protection layer, etc. is formed. This aluminum cylindrical substrate can produce an electrophotographic photosensitive member at low cost and light weight, and moreover, when the surface layer is formed of an amorphous silicon (a-Si) -based material, the substrate can be manufactured. It has an advantage that the adhesion between the aluminum surface and the film-like surface layer formed on the surface of the aluminum is increased, and the reliability can be improved.

The above-mentioned surface layer can be formed by using a deposit film forming apparatus such as a plasma CVD apparatus or a glow discharge decomposition apparatus. If such a plasma CVD apparatus or the like is used, one apparatus can roughen the outer peripheral surface of the cylindrical substrate and form each layer constituting the surface layer while maintaining the vacuum state in the vacuum reaction chamber. Can be performed continuously (see Patent Documents 1, 2, etc.).

The cylindrical substrate is manufactured in a substrate manufacturing process or a factory different from the above-mentioned film forming process, and is transferred to a surface layer film forming process or a factory in a state where the outer surface is exposed, which is called a raw tube. It is transported and delivered. As disclosed in Patent Document 3, the cylindrical substrate is manufactured by cutting a tubular body obtained by hot-extruding or cold-drawing an aluminum-based material to a predetermined length, for example, on the outer surface of the cylindrical substrate. After performing centerless polishing, both ends of this substrate are machined with the in-row part by cutting with the outer surface as the processing standard, and the machined surface of the in-row part is used as the processing standard for this substrate. It is performed by a method of cutting the outer surface.

Japanese Unexamined Patent Publication No. 10-186698 JP-A-2009-64030 Japanese Unexamined Patent Publication No. 2003-162078

By the way, as described above, the raw tube of the cylindrical substrate before the film forming process undergoes metal processing such as end cutting and cutting, and because of the accuracy of the cutting process or because the stress due to the cutting process is accumulated. , The circumferential shape of the outer surface, which is the outer peripheral surface of the raw pipe, is different for each raw pipe. Therefore, it is possible that some of the raw tubes of the cylindrical substrate do not meet the design specifications partially in the circumferential direction, or the circumferential shape of the outer surface fluctuates in the circumferential direction. There is, and it is considered that the roundness of the outer surface of such a cylindrical substrate is reduced.

As described above, the circumferential shape of the outer surface is partially different in the circumferential direction, that is, a raw tube having a reduced roundness is used as a cylindrical substrate, and a surface layer is formed on the outer surface. When the electrophotographic photosensitive member is incorporated into an image forming apparatus and printing is performed, the gap, gap, contact pressure, etc. between the electrophotographic photosensitive member and the rollers or blades located around the electrophotographic photosensitive member fluctuates in the circumferential direction, resulting in a shading pattern. It may cause image abnormalities such as.

An object of the present disclosure is to provide a method capable of stably producing an electrophotographic photosensitive member having high print quality, a high-quality electrophotographic photosensitive member obtained by the method, and the electrophotographic photosensitive member. It is an object of the present invention to provide an image forming apparatus capable of suppressing the occurrence of an image abnormality.

The method for producing an electrophotographic photosensitive member of the present disclosure is a method for producing an electrophotographic photosensitive member having a surface layer on the outer peripheral surface of a cylindrical substrate.
A measurement preparation step in which a cylindrical substrate to be measured is placed at a predetermined object measurement position in the roundness measuring device, and a measurement preparation step.
While the cylindrical substrate and the roundness measuring device are relatively rotated, the outer peripheral surface of the cylindrical substrate is measured at the object measurement position over the entire circumference, and the reference circle and roundness of the outer peripheral surface are measured. The roundness measurement step to calculate and
The necessity of the thin-film deposition mask for the cylindrical substrate is determined by comparing the value of the roundness of the outer peripheral surface calculated in the roundness measurement step with the value of the predetermined reference roundness. Deposition mask necessity judgment step and
When it is determined in the step of determining the necessity of a vapor deposition mask that a vapor deposition mask is necessary, the outer periphery thereof is located at the end or edge of the cylindrical substrate in the rotation axis direction with respect to the determined cylindrical substrate. A thin-film mask addition step of arranging a plurality of thin-film masks that prevent the surface layer from adhering to the area on a strip-shaped mask target region that is continuous in the circumferential direction at intervals in the circumferential direction.
A surface layer film forming step of depositing a surface layer on the outer peripheral surface of the cylindrical substrate including the vapor deposition mask, and a surface layer film forming step.
A thin-film mask removal step of removing the thin-film mask on the outer peripheral surface from the cylindrical substrate for which the formation of the surface layer has been completed.
When it is determined in the vapor deposition mask necessity determination step that the vapor deposition mask is unnecessary, a non-defective film forming step of forming a surface layer on the outer peripheral surface of the determined cylindrical substrate is included. ..

Further, the electrophotographic photosensitive member of the present disclosure is manufactured by using the above-mentioned manufacturing method.

Further, the image forming apparatus of the present disclosure includes the above-mentioned electrophotographic photosensitive member.

According to the method for producing an electrophotographic photosensitive member of the present disclosure, it is possible to stably produce an electrophotographic photosensitive member having high printing quality in which the occurrence of image abnormalities is suppressed. Further, the electrophotographic photosensitive member manufactured by using this manufacturing method and the image forming apparatus including the electrophotographic photosensitive member can suppress the occurrence of image abnormality.

It is a flow chart which shows the outline of the manufacturing method of the electrophotographic photosensitive member of an embodiment. (A) is a semi-cross-sectional view of the electrophotographic photosensitive member of the embodiment, and (b) is a configuration example of a surface layer formed on the outer peripheral surface of the electrophotographic photosensitive member of the embodiment. It is a structural drawing which shows the structure of the image forming apparatus of embodiment in a partial cross section. In each of (a) and (b), the sliding contact position between the electrophotographic photosensitive member 10 and the roller 113B of the magnetic roller (development roller) and the position of the charged region (Zone) as viewed from the direction of arrow E in FIG. It is a figure which shows the relationship. It is a figure explaining the method of measuring the roundness of a cylindrical substrate. Both (a) and (b) are diagrams for explaining an example of the arrangement position of the vapor deposition mask corresponding to the outer peripheral surface shape of the cylindrical substrate. It is a figure explaining the example of the arrangement position of the vapor deposition mask corresponding to the other outer peripheral surface shape of a cylindrical substrate. It is a figure explaining the example of the arrangement position of the vapor deposition mask corresponding to the other outer peripheral surface shape of a cylindrical substrate. This is an example of a thin-film deposition mask applied to the end of a cylindrical substrate, and an example using tape is shown. This is an example of a thin-film deposition mask applied to the end of a cylindrical substrate, and an example of using an end cover is shown. This is an example of a thin-film deposition mask applied to the end of a cylindrical substrate, and an example of using another jig-like end cover is shown.

Hereinafter, a method for manufacturing an electrophotographic photosensitive member according to an embodiment, an electrophotographic photosensitive member and an image forming apparatus provided with the electrophotographic photosensitive member will be described with reference to the drawings. In the embodiment, the longitudinal direction of the cylinder along the tubular length direction of the electrophotographic photosensitive member is referred to as a rotation axis direction or simply an axial direction. The "roundness" used below is measured by applying JIS B 0621-1984 "Definition and display of geometric deviation" and JIS B 7451-1997 "Roundness measuring machine" mutatis mutandis. It shall represent the roundness of the outer peripheral surface of the substrate measured around the "rotation axis" (center of rotation) with respect to the "reference circle".

First, the configuration of the electrophotographic photosensitive member 10 of the present embodiment and the outline of how it is used in the device will be described.
The electrophotographic photosensitive member 10 of the embodiment shown in the configuration diagram of FIG. 2A is used by being incorporated as an electrophotographic photosensitive member or an electrophotographic photosensitive member unit in the image forming apparatus 100 shown in FIG. The electrophotographic photosensitive member 10 has a pressure-resistant layer 2a, a charge injection blocking layer 2b, a photoconductive layer 2c, as shown in FIG. 2B, on an outer peripheral surface 1a which is the outermost surface of a cylindrical substrate 1 made of metal. The surface layer 2 composed of the surface protective layer 2d is laminated (deposited).

When the electrophotographic photosensitive member 10 is incorporated into the image forming apparatus 100 of FIG. 3 and used, the sliding contact position between the electrophotographic photosensitive member 10 and the magnetic roller (development roller) 113A as viewed from the direction of arrow E in FIG. As shown in "FIGS. 4 (a) and 4 (b)", which is a diagram showing the positional relationship between the electrophotographic photosensitive member 10 and the charged region (indicated by Zone in the figure), both ends of the magnetic roller 113A in the axial direction. The two rollers 113B come into contact with predetermined positions near the ends on both sides of the electrophotographic photosensitive member 10 in the rotation axis direction and rotate, so that a minute gap (a minute gap between the electrophotographic photosensitive member 10 and the magnetic roller 113A) ( The so-called gap) is defined, and stable printing is possible.

Then, the electrophotographic photosensitive member 10 of the present embodiment uses the manufacturing method described later shown in FIG. 1 to bring the electrophotographic photosensitive member 10 into contact with the electrophotographic photosensitive member 10 at the time of printing when the electrophotographic photosensitive member 10 rotates. Since the rotation and the gap are stable, high imprint quality and image reproducibility can be maintained. The manufacturing method will be described below.

The method for producing an electrophotographic photosensitive member of the embodiment is a method for producing an electrophotographic photosensitive member having a surface layer on the outer peripheral surface of a cylindrical substrate, and is measured by a roundness measuring device as shown in FIG. A measurement preparation step for arranging the target cylindrical substrate, a roundness measurement step for calculating the reference circle and roundness of the outer peripheral surface by measuring the outer peripheral surface of the cylindrical substrate over the entire circumference, and the measured cylindrical shape. A step of determining the necessity of a vapor deposition mask for a substrate, a step of adding a vapor deposition mask to apply a vapor deposition mask to a cylindrical substrate determined to require a vapor deposition mask, and a step of adding a vapor deposition mask to the cylindrical substrate including the vapor deposition mask. It includes a surface layer film forming step of depositing a surface layer on the outer peripheral surface and a vapor deposition mask removing step of removing the vapor deposition mask from the cylindrical substrate after the film formation.

When it is determined that the vapor deposition mask is unnecessary in the above-mentioned step of determining the necessity of the vapor deposition mask, a non-defective film formation step of forming a surface layer by depositing a surface layer on the outer peripheral surface is performed on the determined cylindrical substrate. Run. Since the non-defective product film forming step is the same as the surface layer film forming step described above except for the presence or absence of the vapor deposition mask, detailed description thereof will be omitted.

In the measurement preparation step in FIG. 1, for example, the cylindrical substrate 1 to be measured is placed at a predetermined object measurement position in a roundness measuring device having a rotation measuring table as shown in FIG. 5 to prepare for measurement. It is a process. Reference numerals X and Y in FIG. 5 indicate a measuring probe including a dimension measuring instrument and a displacement sensor, and reference numeral Z indicates a lower chuck.

The measurement probes X and Y may be contact type, but it is preferable to use non-contact type when it is desired to avoid minute measurement marks depending on the measurement position. Further, the lower chuck indicated by reference numeral Z also serves as a turntable connected to the rotation drive mechanism. The lower chuck Z can detect the rotation angle and the phase in the circumferential direction in synchronization with a stepping motor or the like that drives the lower chuck Z.

The cylindrical substrate 1 serves as a support for the surface layer 2, and at least the surface of the cylindrical substrate 1 has conductivity, and as shown in the semi-cross-sectional view of FIG. 2A, in the tubular length direction. It includes an outer peripheral surface 1a and an inner peripheral surface 1b that are continuous in a certain axial direction, and an end surface 1c that is a substrate end surface (hereinafter, simply referred to as “end surface”) formed at both ends in the axial direction.

A drum attachment called a flange 3 is centered on the rotation axis of the cylindrical substrate 1 indicated by the alternate long and short dash line in the region of the inner peripheral surface 1b that is open at both ends of the cylinder and adjacent to the end surface 1c. Circumferential step portions 1d for precisely fitting the inro (inro) are formed. Further, each end face 1c has at least a circumferential step portion in consideration of contact with the flange 3 described above and the turntable of the roundness measuring device described later and handling in a film forming process or the like to be performed later. It is formed so as to be perpendicular to the peripheral surface of 1d, preferably the peripheral surface of the circumferential step portion 1d and the outer peripheral surface 1a.

The cylindrical substrate 1 has a cylindrical shape, for example, aluminum (Al), stainless steel (SUS), zinc (Zn), copper (Cu), iron (Fe), titanium (Ti), nickel (Ni), and chromium (Cr). ), Tantal (Ta), Tin (Sn), Gold (Au), Silver (Ag), Magnesium (Mg) and Manganese (Mn), or alloys containing these exemplified metal materials make the whole conductive. It is formed as having sex.

Further, in the cylindrical substrate 1, a conductive film made of the above-exemplified metal material or a transparent conductive material such as ITO (Indium Tin Oxide) or tin dioxide (SnO _{2) is adhered to the surface of resin, glass, ceramics or the like.} It may be a thing.

Among these exemplified materials, an aluminum (Al) -based material may be used as the material for forming the cylindrical substrate 1. The cylindrical substrate 1 of the embodiment was entirely made of an aluminum (Al) -based material. As the aluminum (Al) -based material, the electrophotographic photosensitive member 10 can be manufactured lightweight and at low cost, and the pressure-resistant layer 2a, the charge injection blocking layer 2b, and the photoconductive layer 2c described later are formed of amorphous silicon (a-Si). ) When it is formed of a material, the adhesion between those layers and the cylindrical substrate 1 is increased, and the reliability can be improved.

The measurement target position of the cylindrical substrate 1 in the roundness measuring device, that is, the illustrated vertical position of the measuring probes X and Y is the position of the magnetic roller (development roller) 113A after being incorporated into the image forming device 100 described above. It is set at a position near the end of the cylindrical substrate 1 in consideration of contact or sliding contact with the roller 113B. The alternate long and short dash line in the figure is a circumference indicating a virtual end of a charged region when incorporated in the image forming apparatus 100. Although it depends on the model to be incorporated, the roundness measurement position is usually set near the end of the cylindrical substrate 1, that is, the distance from the end surface 1c on the outer peripheral surface 1a is set to a position of 2 to 50 mm. In the example described later, the measurement was performed at a position 15 mm from each of both end faces 1c.

Further, the grip (chuck) of the cylindrical substrate 1 to be measured in the illustrated vertical direction is the inner peripheral surface of the image forming apparatus 100 in the same manner as the flange 3 in consideration of the actual rotation to which the flange 3 is attached. This is performed by fitting an inro (inro) to the circumferential step portion 1d provided in 1b. As a result, the rotation axis of the cylindrical substrate 1 and the rotation axis of the chuck Z of the roundness measuring device can be accurately centered (centered). A chuck for centering may also be provided at the upper end of the cylindrical substrate 1 in the vertical direction shown in the drawing.

When the setting of the cylindrical substrate 1 into the roundness measuring device is completed, the roundness measuring step is executed. In the roundness measurement step, the outer circumference of the cylindrical base 1 at the above-mentioned object measurement position is performed while rotating the cylindrical base 1 relative to the roundness measuring device using the above-mentioned roundness measuring device. This is a step of measuring over the entire circumference of the surface 1a. In this measurement, for example in the case of radial method, the distance from the center of rotation "radius r _n", and records the measured over the entire circumference of the outer peripheral surface 1a. The control device or computer such as a roundness measuring apparatus, the circumferential shape of the outer peripheral surface 1a of the recording radius r _n of the above, as illustrated in FIGS. 6-8, the measured cylindrical substrate 1 (Thick line with measurement point: roundness curve), the corresponding reference circle S of the outer peripheral surface with respect to the center of rotation, and the roundness are calculated for each cylindrical substrate 1 to be measured. Calculated by

The number of measurement points n of the radius r depends on the diameter φ of the cylindrical substrate 1 or the shape and tip diameter of the stylus, but is about 5000 to 10000 points (n = 5000 to 10000) with a radius r of 30 mmφ. .. However, since it would be complicated to display all of them, in the examples of FIGS. 6 to 8, the measurement results are extracted every 10 ° and displayed at 36 points (360 °). Further, Rs in the figure shows the radius of the reference circle _{S, r max} and _{r min} are measured maximum values in the radius _{r n} (the maximum value) and the minimum value (minimum value), respectively.

Next, when the circumferential shape (roundness curve) of the outer peripheral surface 1a of the cylindrical substrate 1 to be measured is determined, the control device or computer of the roundness measuring device can be used with JIS B 7451-1997 "roundness". The above-mentioned measurement with respect to any one of the minimum square center (LSC), the minimum region center (MZC), the minimum circumferential circle center (MCC), and the maximum inscribed circle center (MIC) described in Annex 1 of "Measuring Machine". The difference between the maximum radius (r _max ) and the minimum radius (r _min ) of the roundness curve is evaluated as the "roundness" of the outer peripheral surface 1a of the measurement target. As a reference, the minimum circumscribed circle (Circumcircle) and the maximum inscribed circle (Incircle) of the measured roundness curve are shown in FIG. 6A.

Then, as shown in FIG. 1, the vapor deposition mask necessity determination step is executed. In the vapor deposition mask necessity determination step, the measurement roundness value of the outer peripheral surface 1a described above is compared with a predetermined reference roundness value, and the necessity of the vapor deposition mask for the measured cylindrical substrate 1 is necessary. Is a step of determining.

For example, when the reference roundness is set to 5 μm, the control device or computer of the roundness measuring device described above is a measuring cylinder if the measured roundness of the measured outer peripheral surface 1a is 5 μm or more. It is determined that the roundness of the state substrate 1 needs to be improved, and the necessity of the vapor deposition mask is determined to be "necessary". On the contrary, if the measured roundness of the measured outer peripheral surface 1a is less than 5 μm, it is judged that the roundness of the measured cylindrical substrate 1 does not need to be improved, and the necessity of the vapor deposition mask is set to “No”. Judgment (see FIG. 1).

Here, for the cylindrical substrate 1 having a measured roundness of less than 5 μm, for which it is determined that improvement in roundness is not necessary, the following step of adding a vapor deposition mask is skipped, and a conventional method for manufacturing an electrophotographic photosensitive member is performed. Similarly, the process proceeds to the surface layer deposition step.

On the other hand, the cylindrical substrate 1 having a measured roundness of 5 μm or more, which is determined to require improvement in roundness, proceeds to the vapor deposition mask addition step. In the following step of adding a vapor deposition mask, after the vapor deposition and film formation steps of the surface layer 2 described above, in the cylindrical shape of the substrate 1, the radial shrinkage (diameter reduction) of the portion to which the surface layer 2 is not attached is the surface layer. Focusing on the fact that the surface layer 2 is partially and selectively adhered in the circumferential direction, paying attention to the fact that the portion 2 adhered / formed is larger than the shrinkage in the radial direction, the true shape of the cylindrical substrate 1 is formed. The aim is to improve the roundness. By forming a non-uniform (discontinuous) surface layer 2 in the circumferential direction on the outer peripheral surface 1a at the end or edge, the cylindrical substrate 1 itself is non-uniformly contracted in the circumferential direction in a desired shape. The finding of diameter is a technical idea that did not exist before this disclosure.

That is, in the vapor deposition mask addition step, the outer peripheral surface is located at the end or edge of the cylindrical substrate 1 in the rotation axis direction with respect to the cylindrical substrate 1 for which it is determined that the roundness needs to be improved. A plurality of thin-film masks M that inhibit the adhesion of the surface layer 2 to this region W are arranged at intervals in the circumferential direction on the band-shaped mask target region W that is partially continuous in the circumferential direction of 1a. ..

To give a specific example, for example, in the case of the cylindrical substrate 1 having distortion of the outer peripheral surface that bulges in two directions with the rotation center O in between, as shown in FIG. 6A, a plurality of thin-film depositions are performed. At least one of the masks M is arranged at a _{position (r max ) in the mask target area W where} the value of the measured radius rn is maximized.

Each deposition mask M, roundness curve of the outer peripheral surface (thick line with the measurement point), at a position projecting radially outward from the reference circle S representing the entire circumference average value of each measurement radius r _n there, the value of the measured radius r _n is the position greater than the full circumference average value, are respectively arranged. As described above, this is because at the position where each vapor deposition mask M is arranged, the radial contraction (reduced diameter) of the circumferential portion where the adhesion of the surface layer 2 described later is inhibited is the surface. by utilizing the fact that larger than the site where the layer 2 is deposited, deposition, measuring radius r _n reduced in diameter the base of the big large-diameter portion is measured radius r _n is the diameter of the small diameter portion This is to suppress and improve the roundness of the outer peripheral surface 1a.

Further, in a cross-sectional view orthogonal to the rotation axis of the cylindrical substrate 1 as shown in FIGS. 6 to 8, the plurality of vapor deposition masks M on the outer peripheral surface 1a are in the circumferential direction on the outer peripheral surface 1a of each vapor deposition mask M. The central angles of the sector around the rotation axis corresponding to the positions, for example, the respective angles α shown in FIGS. 6A and 6B, are evenly spaced around the rotation axis and the rotation center O at predetermined angles. Be placed.

That is, in other words, each of these vapor deposition masks M is arranged in the so-called circumferential direction equidistant arrangement. It should be noted that such an arrangement of masks evenly distributed in the circumferential direction is derived from the fact that distortion of the outer peripheral surface 1a of the cylindrical substrate 1 tends to appear evenly distributed in the circumferential direction. Therefore, the circumferential arrangement of the deposition mask M, as described above, to design the arrangement of the position measuring radius r _n protrudes radially outward from the reference circle S basis.

Further, such angle alpha, the central angle of the sector around the axis of rotation of each deposition mask M is projected from the reference circle S of the measuring radius r _n, i.e. it is determined by the magnitude of the roundness. For example, if the measured radius r projecting amount from the reference circle S of _n is small FIG 6 (a), 2 single deposition mask M disposed symmetrically (equal intervals) across the rotation center O are each central angle It is arranged so that α is 30 °.

Also, as in the case projecting amount from the reference circle S of the measuring radius r _n than in FIGS. 6 (a) is large Fig 6 (b), 2 single deposition mask disposed symmetrically (equal intervals) The central angle α of M may be 90 °.

Further, in the case of the cylindrical substrate 1 in which the outer peripheral surface 1a of the cylindrical substrate 1 protrudes in three directions as shown in FIG. 7, the vapor deposition mask is similar to the case of FIGS. 6 (a) and 6 (b) described above. the M, values of the measured radius r _n comprises at least one maximum and a position (r _max), roundness curve of the outer peripheral surface 1a is arranged at a position projecting radially outward from the reference circle S. In this example, each center angle beta of the three deposition mask M is 60 °, the center angle beta, in accordance with the protruding amount from the reference circle S of the measuring radius r _n, may be appropriately changed.

Further, in the case of the cylindrical substrate 1 in which the outer peripheral surface 1a of the cylindrical substrate 1 protrudes in four directions as shown in FIG. 8, the vapor deposition mask M is measured in the same manner as in the cases of FIGS. 6 and 7 described above. the value of the radius r _n comprises at least one maximum and a position (r _max), roundness curve of the outer peripheral surface 1a is to position, i.e. in positions 4 which protrudes outward in a radial direction than the reference circle S. In this example, although the four 45 ° central angle gamma respective deposition mask M, also the central angle gamma, according to the projection amount from the reference circle S of the measuring radius r _n, can be changed as appropriate ..

In order to facilitate the arrangement and design of each thin-film deposition mask M as described above, in the roundness measurement step described above, immediately after the measurement of the outer peripheral surface 1a is completed, the base point of the radius measurement is set to a cylinder. The inner peripheral surface 1b or the end surface 1c of the shape substrate 1 may be engraved with a pen, a ruled line, or the like. For example, FIGS. 6 to 8 show an example in which a mark showing the position of 0 ° is marked on the inner surface of the cylindrical substrate 1 by marking to the extent that the dimensional accuracy of the substrate is not affected.

Further, the length (width in the circumferential direction) of each vapor deposition mask M in the rotation axis direction may be at least 3 mm or more. For example, when the roller 113B of the magnetic roller 113A is located outside the charging region (Zone) of the electrophotographic photosensitive member 10 and on the end side as shown in FIG. 4A, vapor deposition will be described with reference to FIG. The length of the mask M in the rotation axis direction may be 3 mm or more and the distance L1 or less from the end of the substrate of the rollers 113B.

Further, as shown in FIG. 4B, when the roller 113B is located on the center side inside the charged region (Zone) of the electrophotographic photosensitive member 10, the length of the vapor deposition mask M in the rotation axis direction is 3 mm. The distance from the end of the substrate in the charged region may be L2 or less.

Further, as a specific example of the vapor deposition mask M arranged in the mask target region W at the end of the cylindrical substrate 1, the vapor deposition masks M1 to M3 as shown in FIGS. 9 to 11 can be mentioned. These examples correspond to the cylindrical substrate 1 whose outer peripheral surface bulges in two directions as shown in FIG. 6 (b), but the examples in FIG. 6 (a) and FIGS. 7 and 8 and the examples , And other examples as well.

For example, the thin-film deposition mask M1 shown in FIG. 9 is obtained by attaching a tape-shaped thin-film deposition mask M1 such as masking tape to the end of the cylindrical substrate 1. In this case, there is an advantage that the mask of any arrangement can be dealt with immediately and easily.

Further, as the thin-film deposition mask M2 shown in FIG. 10, a plurality of types of thin-film deposition masks M2 having various central angles that can be fitted to the end portion of the cylindrical substrate 1 are prepared in a patterned manner, and if required. It fits into the end. In this case, the vapor deposition mask M2 can be easily arranged at the end portion. Further, in the base tube of the cylindrical substrate 1, projecting from the reference circle S of the measuring radius r _n of the outer circumferential surface 1a (swelling) is, which lot since the the property that just as easily protrude in two directions, in particular It is valid.

The pattern of the vapor deposition mask M2 may be a 15 ° step such as 15 °, 30 °, 45 °, etc., or a step in steps of 10 °. By preparing abundant patterns in advance, it is possible to correspond to the cylindrical substrate 1 of various sizes.

Further, the vapor deposition mask M3 shown in FIG. 11 uses an auxiliary pipe (dummy pipe) DP extending in the rotation axis direction, which is arranged continuously at the end of the cylindrical substrate 1, and the vapor deposition mask is used on the auxiliary pipe DP. Fix M3. This also allows the vapor deposition mask M3 to be easily and quickly disposed. The vapor deposition mask M3 and the auxiliary pipe DP may be separate or integrated.

As the material constituting the vapor deposition mask M, a metal, ceramics containing glass, a resin mainly composed of fluorine, or the like can be used. In particular, although the material is not limited, it is preferable that the material has sufficient heat resistance at the temperature (about 350 ° C.) at the time of film formation described later and does not decompose or emit outgas due to plasma discharge or the like.

Next, a surface layer film forming step for forming the surface layer 2 is performed. The surface layer film forming step is a step of depositing the surface layer 2 on the outer peripheral surface 1a of the cylindrical substrate 1 on which the vapor deposition mask M is arranged.

The surface layer 2 can be formed by using a deposit film forming apparatus such as a plasma CVD apparatus. Further, if such a plasma CVD apparatus or the like is used, the outer peripheral surface 1a of the cylindrical substrate 1 can be continuously roughened and the surface layer can be continuously maintained in a vacuum state in the vacuum reaction chamber by one apparatus. It is possible to perform the formation process of each layer constituting 2.

Briefly explaining each layer constituting the surface layer 2, as shown in FIG. 2B, the pressure-resistant layer 2a on the most cylindrical substrate 1 side and in close contact with the cylindrical substrate 1 has withstand voltage characteristics in the surface layer 2. This is a layer containing, for example, amorphous silicon nitride (a-SiN). Its thickness is 0.5 to 15 μm. The withstand voltage layer 2a is also called a withstand voltage layer or a withstand voltage holding layer. Since the surface layer 2 shown in the drawing emphasizes the thickness of each layer or each film, the layer thickness, the layer thickness ratio, and the like are different from the actual ones.

In the case of positive charge, the charge injection blocking layer 2b has a role of blocking the injection of electrons as carriers from the cylindrical substrate 1, and is formed of, for example, an amorphous silicon (a-Si) -based material. NS. The charge injection blocking layer 2b is, for example, a-Si containing boron (B) and, in some cases, nitrogen (N), oxygen (O), or both in the case of positive charging as a dopant. In the case of negative charge, phosphorus (P) and optionally nitrogen (N), oxygen (O), or both can be used, and the thickness thereof is 2 to 10 μm.

The photoconductive layer 2c has a role of generating carriers by irradiation with light such as laser light, and is, for example, an a-Si-based material and an amorphous selenium (a-Se) -based material such _{as Se-Te or As 2} Se _3. Is formed by. The photoconductive layer 2c of the embodiment is formed of a-Si and a-Si based material in which carbon (C), nitrogen (N), oxygen (O) and the like are added to a-Si and a-Si, and boron (boron) is used as a dopant. B) or phosphorus (P) is contained. When the photoconductive layer 2c is formed by using the a-Si material, the thickness thereof may be set to about 5 to 100 μm, more specifically to 10 to 80 μm. The charge injection blocking layer 2b and the photoconductive layer 2c may be collectively referred to as a “photosensitive layer”.

The surface protective layer 2d has a role of protecting the surface of the photoconductive layer 2c, and is an a-Si-based material such as amorphous silicon carbide (a-SiC) or amorphous silicon nitride (a-SiN), or an amorphous material. Carbon (a-C) may be used, or a multilayer structure thereof may be used. In the embodiment, from the viewpoint of abrasion resistance, the surface protective layer 2d having a structure in which a-C having high resistance is laminated on a-SiC is preferably adopted. The thickness of the surface protective layer 2d may be set to, for example, 0.1 to 2 μm, more specifically 0.5 to 1.5 μm.

Finally, the electrophotographic photosensitive member 10 is completed by performing a vapor deposition mask removing step of removing the vapor deposition mask M on the outer peripheral surface 1a from the electrophotographic photosensitive member 10 for which the formation of the surface layer 2 has been completed.

According to the method for manufacturing the electrophotographic photosensitive member 10 of the present embodiment described in detail above, the position of the cylindrical position in contact with or in sliding contact with the roller 113B of the magnetic roller 113A of the image forming apparatus 100 after cooling is completed after all the steps are completed. Since the roundness with respect to the rotation axis is improved, a high-quality electrophotographic photosensitive member with little fluctuation in the so-called development gap can be stably produced.

Next, a configuration example of the image forming apparatus 100 incorporating the electrophotographic photosensitive member 10 manufactured as described above will be shown.

The image forming apparatus 100 according to the embodiment adopts the Carlson method as an image forming method, and includes the electrophotographic photosensitive member 10 described above, a charger 111, an exposure device 112, and a developing roller 113A described above. The device 113, the transfer device 114, the fixing devices 115A and 115B, the cleaning device 116 including the cleaning roller 116B and the cleaning blade 116A in contact with the electrophotographic photosensitive member, the static eliminator 117 and the like are provided. The arrow along the recording medium P in the drawing indicates the moving direction of the paper which is the recording medium P.

The configuration of the image forming apparatus 100 will be briefly described.

The charger (charging roller) 111 has a role of negatively charging the surface of the negatively charged electrophotographic photosensitive member 10, for example. In the present embodiment, as the charger 111, for example, a contact type charger configured by coating a core metal with conductive rubber or PVDF (polyvinylidene fluoride) is adopted.

The exposure device 112 has a role of forming an electrostatic latent image on the electrophotographic photosensitive member 10. As the exposure device 112, for example, an LED (light emitting diode) head in which a plurality of LED elements (wavelength: 680 nm) are arranged can be adopted.

The developer 113 has a role of developing an electrostatic latent image of the electrophotographic photosensitive member 10 to form a toner image. The developer 113 in this example includes a magnetic roller 113A that magnetically holds the developer (hereinafter, toner) T.

The toner T constitutes a toner image formed on the surface of the electrophotographic photosensitive member 10, and is triboelectrically charged in the developing device 113. Examples of the toner T include a two-component developer containing a magnetic carrier and an insulating toner, and a one-component developer containing a magnetic toner.

The magnetic roller 113A has a role of transporting the toner T to the developing region on the surface of the electrophotographic photosensitive member 10. The magnetic roller 113A conveys the triboelectric toner T in the developing device 113 to the surface of the electrophotographic photosensitive member 10 in the form of a magnetic brush adjusted to a constant ear length.

The transfer device 114 has a role of transferring the toner image of the electrophotographic photosensitive member 10 to a recording medium P such as paper supplied to the transfer region between the electrophotographic photosensitive member 10 and the transfer device 114. .. The transfer device 114 in this example includes a transfer charger 114A and a separation charger 114B.

The fuser 115 has a role of fixing the toner image transferred to the recording medium P to the recording medium P, and includes a pair of fixing rollers 115A and 115B. The fixing rollers 115A and 115B are, for example, metal rollers whose surface is coated with ethylene tetrafluoride or the like.

The cleaner 116 has a role of removing the toner T remaining on the surface of the electrophotographic photosensitive member 10, and includes a cleaning roller 116B and a cleaning blade 116A.

The static eliminator 117 has a role of removing the surface charge of the electrophotographic photosensitive member 10, and a device capable of emitting light having a specific wavelength (for example, 630 nm or more) is used.

By providing the electrophotographic photosensitive member 10 having a small roundness described above, the image forming apparatus 100 of the present embodiment stably obtains a high-quality printed image with little fluctuation in the so-called development gap. be able to. That is, high print quality can be stably maintained.

The present invention is not limited to those shown in the above-described embodiments, and can be improved or modified without departing from the gist of the present invention.

For example, in the above-described embodiment, the measurement of roundness is shown by the radius method, but the measurement may be performed by the diameter method using a contact type or non-contact type measurement probe. As described above, the protrusion (bulge) of the outer peripheral surface 1a from the reference circle S in the raw pipe of the cylindrical substrate 1 has the property that it easily protrudes in two directions in the same manner in all lots, and therefore the measured circle. The mask target region W may be set in the portion of the circumferential shape having the largest diameter with respect to the reference circle S, and the vapor deposition mask M may be arranged in the region W. In this case as well, the roundness of the cylindrical substrate 1 can be improved.

Next, a cylindrical substrate (sample) determined to require a vapor deposition mask is used because the measured roundness is 5 μm or more through the above-mentioned “roundness measurement step” and “deposition mask necessity determination step”. The case where the film is formed after applying the vapor deposition mask of the present disclosure (Examples 1 to 5) and the case where the film is formed on the entire circumference without the vapor deposition mask (Comparative Examples 1 and 2) are perfect circles. We evaluated how much the degree was improved.

“Table 1” below shows the film formation of the cylindrical substrates (bare tubes) of Examples 1 to 5 with a vapor deposition mask and the cylindrical substrates (bare tubes) of Comparative Examples 1 and 2 without a vapor deposition mask. It is a list of the previous specifications and the roundness of the "electrophotographic photosensitive member (product)" after film formation. In addition, "Table 1" specifies the specifications of the vapor deposition mask applied to each sample.

As each of the cylindrical substrates, those having a length of 360 mm in the rotation axis direction were used. Further, for the measurement of roundness, the roundness measuring device shown in FIG. 5 was used, and the measurement position was set to a position (roller position) of L = 15 mm from both end faces.

Although detailed description of the film forming conditions is omitted, the total thickness of the surface layer formed by the film forming is 20 μm. The breakdown is a pressure resistant layer (2 μm), a charge injection blocking layer (3 μm), a photoconductive layer (14 μm), and a surface protective layer (1 μm).

As a vapor deposition mask that protects the end portion of the cylindrical substrate (prevents adhesion of the surface layer), a heat-resistant adhesive tape made of polyimide (two types of masking tape having a width of 5 mm and a width of 10 mm) was used. Then, as in the pattern described in the above-described embodiment, this polyimide tape was attached to both ends (mask target area W) of the cylindrical substrate as a vapor deposition mask in the following pattern.

For example, with respect to a cylindrical substrate (Examples 1, 2, and 4) having an "elliptical" outer peripheral surface, the central angle α is 90 ° and rotation is performed as shown in FIG. 6 (b). Polyimide tapes (tape width 5 mm or 10 mm) having a predetermined circumferential length were attached to two positions (maximum positions of roundness) diagonally (equally distributed) with the center in between.

Further, with respect to the cylindrical substrate having a “triangular” shape on the outer peripheral surface (Example 3) and the cylindrical substrate having a “square” shape on the outer peripheral surface (Example 5), FIG. 7 respectively. And as shown in FIG. 8, the central angle is β (60 °) or γ (45 °), and the positions are diagonally (equally distributed) with the center in between. A polyimide tape having a length in the circumferential direction (tape width is 5 mm or 10 mm) was attached as shown in the figure.

As shown in Table 1, the results after film formation show that the cylindrical substrates of Examples 1 to 5 using the vapor deposition mask partially continuous in the circumferential direction (discontinuous in the circumferential direction) were formed into a film. It can be seen that the roundness of the outer peripheral surface of each of the electrophotographic photosensitive members is improved. On the other hand, in the electrophotographic photosensitive member formed without using the vapor deposition mask, the roundness deteriorated or did not change.

In this way, by attaching a vapor deposition mask that is discontinuous in the circumferential direction, a surface layer that is non-uniform (discontinuous) in the circumferential direction is formed at the end or edge of the outer peripheral surface of the cylindrical substrate, thereby forming a perfect circle. It is possible to reduce the diameter of a cylindrical substrate having an inferior degree in a non-uniform manner in the circumferential direction in a desired shape and improve its roundness.

Further, depending on the manufacturing method of the embodiment and the example, the roundness of the cylindrical substrate (delivered raw tube) is usually out of the standard of 5 μm or more, and the specification as a final product (photoreceptor) is not satisfied, which is not possible. It becomes possible to commercialize a photoconductor that is disposed of as a non-defective product. Therefore, the yield of the cylindrical substrate in lot units can be improved, and as a result, the cost of the electrophotographic photosensitive member can be reduced.

1 Cylindrical substrate 1a Outer peripheral surface 1b Inner peripheral surface 1c End surface 1d Circumferential step 2 Surface layer 3 Flange 10 Electrophotographic photoconductor M, M1, M2, M3 Evaporation mask

100 Image forming device 111 Charger 112 Exposure device 113 Developer 113A Magnetic roller 114 Transfer device 114A Transfer charger 114B Separation charger 115 Fixer 115A, 115B Fixing roller 116 Cleaning device 116A Cleaning blade 116B Cleaning roller 117 Static eliminator P Recording medium T toner (developer)

Claims (4)

A method for producing an electrophotographic photosensitive member having a surface layer on the outer peripheral surface of a cylindrical substrate.
A measurement preparation step in which a cylindrical substrate to be measured is placed at a predetermined object measurement position in the roundness measuring device, and a measurement preparation step.
While the cylindrical substrate and the roundness measuring device are relatively rotated, the outer peripheral surface of the cylindrical substrate is measured at the object measurement position over the entire circumference, and the reference circle and roundness of the outer peripheral surface are measured. The roundness measurement step to calculate and
The necessity of the thin-film deposition mask for the cylindrical substrate is determined by comparing the value of the roundness of the outer peripheral surface calculated in the roundness measurement step with the value of the predetermined reference roundness. Deposition mask necessity judgment step and
When it is determined in the step of determining the necessity of a vapor deposition mask that a vapor deposition mask is necessary, the outer periphery thereof is located at the end or edge of the cylindrical substrate in the rotation axis direction with respect to the determined cylindrical substrate. A thin-film mask addition step of arranging a plurality of thin-film masks that prevent the surface layer from adhering to the area on a strip-shaped mask target region that is continuous in the circumferential direction at intervals in the circumferential direction.
A surface layer film forming step of depositing a surface layer on the outer peripheral surface of the cylindrical substrate including the vapor deposition mask, and a surface layer film forming step.
A thin-film mask removal step of removing the thin-film mask on the outer peripheral surface from the cylindrical substrate for which the formation of the surface layer has been completed.
When it is determined in the vapor deposition mask necessity determination step that the vapor deposition mask is unnecessary, a non-defective film forming step of forming a surface layer on the outer peripheral surface of the determined cylindrical substrate is provided.
A method for producing an electrophotographic photosensitive member including. The method for producing an electrophotographic photosensitive member according to claim 1, wherein at least one of the plurality of thin-film vapor deposition masks is arranged at a position in the mask target region where the value of the radius or the diameter is maximum. Each vapor deposition mask is arranged at a position where the circumferential shape of the outer peripheral surface protrudes radially outward from the reference circle, and the radius or diameter value is larger than the all-around average value. The method for producing an electrophotographic photosensitive member according to claim 1. In a cross-sectional view orthogonal to the rotation axis of the cylindrical substrate, the plurality of vapor deposition masks have a fan-shaped central angle around the rotation axis corresponding to the circumferential position on the outer peripheral surface of each vapor deposition mask. The method for manufacturing an electrophotographic photosensitive member according to claim 1, wherein the electrophotographic photosensitive member is arranged at equal intervals with a predetermined angle around it.

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