JPH01167761A - Surface-treated base member for electrophotographic photoreceptor and method for manufacturing the same - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field to which the Invention Pertains] The present invention relates to a substrate member suitable for surface-processing a metal body, particularly for an electrophotographic photoreceptor for a laser, and a method for manufacturing the same.

[Description of prior art]

Metal bodies in the shape of plates, cylinders, endless belts, etc. are used as substrates (support bodies) of photoconductive members such as electrophotographic photoreceptors, and these metal bodies have a surface shape suitable for the purpose. That is required.

Therefore, the surfaces of these metal bodies are subjected to various cutting or polishing processes.

As the metal body, an aluminum alloy is generally used as the most suitable one, and the surface thereof is subjected to the above-described processing to obtain a desired surface, and a light-receiving layer according to the purpose is formed on the surface.

However, according to the conventional cutting method or polishing method, the alloy structure contains 5i-All-Fe system, Fe-Aj! system, intermetallic compounds such as TiBz, A6°Mg, T t,
In addition to the presence of oxides of S t and Fe and the presence of vacancies due to H2, surface defects such as grain boundary steps occurring between neighboring Attlli weaves with different crystal orientations may occur. There is.

Furthermore, when applying an aluminum alloy to a substrate, an extremely clean surface is used, and the surface of an aluminum alloy with such a surface condition is active even under an ultra-high vacuum such as IQ-'mHg. An oxide film about 30 times thicker is formed.

Substrates obtained by surface processing using conventional cutting or polishing methods in areas with such problems end up causing various problems and defects in the functionality of photoconductive members manufactured using the substrates. Become.

For example, in the case of an electrophotographic photoreceptor, the photoreceptive layer formed on the substrate may have poor uniformity or uniformity, or may have poor electrical, optical, and/or photoconductive properties. In many cases, the image becomes non-uniform, causing defects in the image, and ultimately rendering the image unusable. This point is remarkable when the photoreceptive layer is formed of silicon or an amorphous material mainly composed of silicon.

To solve the above-mentioned problems of the prior art, for example, ff1X has been proposed in Japanese Patent Application Laid-Open No. 61-231561.

This proposal is extremely effective as a solution to the above problems. However, in the case of an image forming member using a laser as the image exposure light source, there remains a problem that needs to be solved in terms of the generation of interference fringes on the image. Regarding this point,
There is strong market demand for even higher quality images,
In order to meet such requirements, it is desirable to suppress the problem of interference fringes on the image forming member side.

[Purpose of the invention]

The main object of the present invention is to
An object of the present invention is to provide a substrate member for an electrophotographic photoreceptor and a method for manufacturing the same, which improves the invention described in 2.1 and has a further improved interference fringe prevention effect.

[Structure and effects of the invention]

The present inventors have discovered an optimal surface shape for a substrate member for electrical or electronic devices, particularly electrophotographic photoreceptors, etc.
Moreover, as a result of extensive research to overcome the problems caused by the conventional surface shapes and processing methods mentioned above, we have developed a system that allows a rigid sphere with a specific surface shape to fall naturally from a predetermined height.
The present invention has obtained the knowledge that the object of the present invention can be achieved by colliding with the surface of the workpiece substrate by forcing it to fall, inverting the surface shape of the rigid sphere and forming similar spherical trace depressions, and said knowledge. As a result of further research based on
The present invention has now been completed.

The present invention provides an improved substrate member for an electrophotographic photoreceptor and a method for manufacturing the same.

The base member provided by the present invention has an uneven surface formed by a plurality of spherical trace depressions, and the shape of the unevenness due to the spherical trace depressions forms a continuous curve on the slope thereof,
The slope is characterized in that it forms a discontinuous curve at one point at the apex of the recess where it converges.

The method for manufacturing a base member provided by the present invention includes:
A rigid sphere whose surface has irregularities of a constant shape, each convex part has a slope that forms a continuous curve in the cross section, and the slope converges to form a discontinuous curve at the concave part. The method is characterized in that a plurality of rigid spheres are allowed to naturally fall to form irregularities on the surface of the workpiece base member due to the trace depressions of the rigid spheres. This is a method for producing a base member for an electrophotographic photoreceptor, the shape of which is a continuous curve on its slope, and a discontinuous curve at one point at the apex of the recess where the slope converges.

Hereinafter, the details of the present invention will be explained.

The surface-treated base member provided by the present invention is basically as shown in FIG.

That is, the base member 1 is formed by forming irregularities on the surface 2 by a plurality of spherical trace depressions 4.

That is, for example, the spherical trace depression 4 is formed by allowing the rigid sphere 3 to fall naturally from a position at a predetermined height H from the surface 2. Therefore, by dropping a plurality of rigid spheres 3 from substantially the same height H, a plurality of spherical trace depressions having substantially the same shape can be formed on the surface 2.

FIGS. 2(A) and 2(B) illustrate vestigial depressions formed in such a case.

In the example shown in FIG. 2(A), a plurality of spheres 3 having substantially the same shape are dropped from substantially the same height onto different parts of the surface 2 of the base member l to form a plurality of depressions 4 having substantially the same shape so as to overlap each other. They are formed sparsely and compacted to the extent that they do not occur, forming unevenness.

In the example shown in FIG. 2(B), a plurality of spheres 3 having substantially the same shape are dropped from substantially the same height onto different parts of the surface 2 of the base member 1 to form a plurality of depressions 4 having substantially the same shape so as to overlap each other. The height of the unevenness is reduced compared to the example shown in FIG. 2(A) by forming the unevenness densely so that they fit together. In this case, it is necessary to allow the spheres to fall naturally so that the times when the overlapping depressions 4 are formed, that is, when the spheres 3 collide with the surface 2 of the base member 1 are shifted from each other.

In this way, the desired shape can be created on the surface of the base member by appropriately adjusting conditions such as the hardness of the rigid sphere and the surface of the base member, the diameter of the rigid sphere, the surface shape of the rigid sphere, the falling height, and the amount of falling balls. A plurality of trace depressions can be formed at a predetermined density.

Therefore, by selecting the above conditions, it is possible to freely adjust the surface roughness, that is, the height and pitch of the unevenness, such as finishing the surface of the base member to a mirror finish or a non-mirror finish, and also to adjust the surface roughness, such as the height and pitch of the unevenness, according to the purpose of use. It is also possible to form unevenness in a desired shape.

Furthermore, by using the method of the present invention, poor surface conditions on the surface of boathole tubes or mandrel extruded and drawn AI tubes can be corrected and finished into desired surface conditions. This is because the regular irregularities on the surface are plastically deformed by the collision of the rigid spheres.

The base member 1 according to the present invention is made of a rigid sphere having a specific surface shape. In other words, in the surface shape of a rigid sphere, the slope is a continuous curve, but at one point on the top of the convex part it is a discontinuous curve.
It has M4Q conical irregularities, and by colliding the hard sphere with this specific surface shape with the surface of the base member, it is possible to form a hard sphere trace depression having a similar inverted shape on the surface of the base member. The hard sphere trace recesses having such a specific surface shape are formed by using, for example, a hard sphere having pseudo-conical irregularities on its surface as shown in FIG. 3A.

Rigid spheres with a specific shape on the surface can be made uneven by mechanical processing, plastic processing such as embossing or corrugation, or chemical methods such as etching with acid or alkali. It can be easily created by the method of forming. Further, electrolytic polishing, chemical polishing, final polishing, etc., or anodic oxide film formation, chemical film formation, plating, waxing, painting, vapor deposition film formation, film formation by CVD method, etc., on the surface of the rigid sphere with the unevenness formed in this way, etc. The surface treatment can be applied to adjust the uneven shape (height), hardness, etc. as appropriate.

The rigid sphere used in the present invention includes metals such as stainless steel, aluminum, steel, nickel, and brass, ceramics,
Various rigid spheres such as plastic can be used, with rigid spheres of stainless steel and steel being preferred, especially for reasons of durability and cost reduction.The hardness of the sphere may be higher or lower than that of the metal body. However, if the sphere is to be used repeatedly, it is preferable that the hardness be higher than that of the metal body.

By the way, the method of the present invention can be applied to base members made of any material, and therefore, these base members may be electrically conductive or electrically insulating.

Examples of the conductive substrate member include NiCr.

Stainless steel, 1. Cr, Mo, Au, Nb.

Examples include metals such as Ta, V, Ti, Pt, and Pb, and alloys thereof.

Materials for electrically insulating substrates include polyester, polyethylene, polycarbonate, cellulose, acetate,
Examples include films or sheets of synthetic resins such as polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, and polyamide, glass, ceramics, and paper. These electrically insulating substrate members are preferably provided with a conductive treatment on one surface and a light-receiving layer on the conductive surface side.

For example, if it is glass, NiCr is applied to its surface.

An! , Cr, Mo, Au, Ir, Nb, Ta, V.

Ti, P L, Pd, In, o,, SnO,, ITO
(Ingo3+5n01), etc., to give conductivity by providing a thin H, or if it is a synthetic resin film such as a polyester film, NiCr,
A1. Ag, Pb, Zn, Ni,
Au.

Cr, Mo, Ir, Nb, Ta,
A thin film of metal such as V, Tjl, or Pt is provided on the surface by vacuum evaporation, electron beam evaporation, sputtering, or the like, or the surface is laminated with the metal to impart conductivity to the surface.

The shape of the base member may be any shape such as a cylinder, a belt, or a plate, but the shape can be determined as appropriate depending on the purpose and desire. for example,
When used as an image forming member for continuous high-speed copying or electrophotography, it is desirable to have an endless belt shape or a cylindrical shape.

The thickness of the base member is determined appropriately so that the desired light-receiving member can be formed, but if flexibility is required as a light-receiving member, the thickness of the base member may be determined appropriately. It can be made as thin as possible within the range. However, from the viewpoint of manufacturing and handling of the base member, mechanical strength, etc., the thickness is usually set to 10μ or more.

The details of the method of the present invention will be explained below using the drawings as necessary. Figures 4(A) and 4(B) schematically show an example of a preferred apparatus used to carry out the method of the present invention.

In FIGS. 4(A) and 4(B), 11 is, for example, an aluminum cylinder for producing a base member. The cylinder 11 may be, for example, a drawn tube, or may be finished with an appropriate surface precision.

The cylinder 11 is supported by a rotating shaft (support) 12, driven by a suitable driving means 13 such as a morph, and is rotatable approximately around its axis.

A rotating container 14 is supported by a bearing 12 and rotated in the same direction as the cylinder 11, and accommodates a large number of rigid balls 15 having specific irregularities on the surface.

The rigid sphere 15 has a plurality of ribs 1 protruding from the inner wall of the container 14.
6 and is transported to the upper part of the container by the rotation of the container 14, and then falls onto the cylinder 11.

The rotation speed and the diameter of the cylinder 11 and the rotating container 14 that holds the rigid sphere 15 are appropriately determined and controlled in consideration of the density of the trace depressions to be formed, the supply amount of the rigid sphere, and the like.

When the rotary container 14 is rotated, the rigid spheres 15 that are transported along the container wall at an appropriate rotation speed fall and collide with the cylinder 11, forming trace depressions and unevenness on the surface thereof.

In addition, holes are uniformly bored in the wall of the container 14, and a mechanism is adopted in which the cleaning liquid is sprayed from the shower pipe 17 outside the container 14 when the container 14 is rotated.
It can also be configured to clean. In this case, dust and the like that adhere to the rigid spheres or due to static electricity generated by contact between the rigid spheres and the rotating vessel are washed out of the rotating vessel, and a desired base member can be manufactured.

Furthermore, in order to prevent uneven drying or dripping, it is preferable to use a nonvolatile substance alone or a mixture with a normal cleaning liquid such as triethane or trichlene as the cleaning liquid.

The substrate member according to the present invention produced with the above structure has excellent image performance when an electrophotographic light-receiving layer is formed on the substrate member of the present invention as an electrophotographic photoreceptor, particularly an electrophotographic photoreceptor for laser use. It is extremely excellent, and is particularly noteworthy in terms of its effect on preventing interference fringes.

The excellent effect of preventing interference fringes in the present invention is achieved by forming spherical trace depressions having a specific shape on the surface of the base member.

The rigid sphere having the specific surface shape shown in FIG. 3(A), that is, a pseudo-conical shape, schematically has the cross-sectional shape shown in FIG. 3(B). In particular, in the present invention, it is particularly important to have a cross-sectional shape as shown in FIG. 3(B). FIG. 3(B) is a cross-sectional view at the diameter of the pseudo-conical bottom surface forming the convex portion, where a indicates the deepest portion of the concave portion, and b indicates the top portion, respectively.

In the present invention, as shown in this figure, the slope forming one convex part forms a roughly continuous curve in other parts, but the convex part is formed so that it is discontinuous at one point b. This is a very important point. The nature of the frequent interference prevention effect of such a convex shape is not clear, but it may be related to the amount of change in the optical path length of the incident light per unit horizontal distance, or it may be related to the growth of the light-receiving member formed thereon. Whether this is due to a modification of the mechanism or a combined effect of these, it is clear that the confinement effect of the interference ring increases, promoting the miniaturization and dispersion of the interference fringe pattern and reducing the average of the macro image. It is assumed that this is due to the

As for the dimension factor 7 of such a shape, it is better that the diameter of the pseudo-cone bottom (L in Figure 3 (B)) is as small as possible;
00 μm or less is sufficient because the interference fringe confinement region cannot be visually discerned. It is effective to prevent interference fringes by making the slopes and tops of the convex parts as steep and pointed as possible, but if the protrusions are too strong, this is undesirable as it may cause image defects or other problems, and if the protrusions are too weak, it is not desirable. In practice, it is preferable to set the diameter to about 11,500 to 115 (h/L relationship in FIG. 3(B)) with respect to the diameter of the bottom of the pseudo cone.

In addition, although Fig. 3 (A) shows the bottom of the y1 cone as a perfect circle, it may be an oval or an irregular shape such as a cloud as long as it has an apex and satisfies the claims of the present invention. I can't help it.

A specific example of a schematic cross section of the base member 1 having a hard ball trace depression obtained by a hard ball having a specific surface shape preferred in the present invention is shown in FIGS. 5(A) to 5(C).

Figure 5(A) is formed by a rigid sphere having the shape shown in Figures 3(A) to (B), and Figure 5(B) is a rigid sphere used in Figure 5(B). It is formed by a rigid sphere in which the convex and concave surfaces of the pseudo-conical slope have opposite shapes.

Furthermore, the fifth (C) [ffl is a base member formed of a rigid sphere having a more complicated pseudo-conical shape.

The base member having hard sphere trace depressions having a specific shape according to the present invention has no intermetallic compounds, metal oxides, etc. in the metal structure, no pores, and has no grains. It has no surface defects such as interfacial steps, and at the same time, when an electrophotographic light-receiving layer is formed on the base member and used as an electrophotographic light-receiving member for a laser, it has extremely excellent performance in terms of interference prevention effect. This provides a high-quality image.

In the photoconductive member of the present invention, when a photosensitive layer made of, for example, an organic photoconductor is provided on the substrate member, this photosensitive layer can be functionally separated into a charge generation layer and a charge transport layer. Moreover, between these photosensitive layers and the base member,
For example, in order to prevent carrier injection from the photosensitive layer to the base member or to improve the adhesion between the photosensitive layer and the base member, an intermediate layer made of, for example, an organic resin can be provided. The charge generation layer may be made of, for example, conventionally known azo pigments, quinone pigments, quinocyanine pigments, perylene pigments, indigo pigments, bishenduimidadul pigments, quinacridine pigments,
Azulene compounds and metal-free phthalocyanine pigments described in JP-A-57-+65263.
e phthalocyanine) = One or more types of phthalocyanine pigments containing metal ions are used as a charge generating substance to bind polyester, polystyrene, polyvinyl butyral, polyvinyl pyrrolidone, methylcellulose, polyacrylic acid esters, cellulose esters, etc. It is formed by dispersing the resin in an organic solvent and coating it. The composition may be, for example, charge generating material 100
The amount is 20 to 300 parts by weight of the binder resin. The thickness of the charge generation layer is preferably in the range of 0.01 to 1.0 μm.

In addition, the charge transport layer may contain, for example, a polycyclic aromatic compound such as anthracene, pyrene, phenanthrene, coronene, etc. in the main chain or side chain, or indole, oxazole, isoxazole, thiazole, imidazole, pyrazole, oxadiazole, pyrazoline, thiadiazole. , compounds with nitrogen-containing cyclic compounds such as triazole, hydrazone compounds, and other transport materials such as polycarbonate, polymethacrylic acid esters, polyarylate, polystyrene, polyester, polysulfone, styrene-acrylonitrile copolymer, styrene-methyl meccrylate copolymer Dispersed using an organic solvent in a binder resin such as
Formed by coating. The thickness of the charge transport layer is 5 to 20μ
It is assumed that m.

Further, when the charge stopping layer and the charge transporting layer are laminated, the order of the layers may be arbitrary. For example, the charge generating layer and the charge transporting layer may be laminated in this order from the base member side. The layer order can also be reversed.

Further, the photosensitive layer mentioned above is not limited to the above, but for example, I
BM Journal of the Re5er
arch and Development + 19
Charge transfer complex consisting of polyvinyl carbazole and trinitrofluorenone disclosed in January 1971, pp. 75-89, U.S. Pat. No. 4,395,183, U.S. Pat. No. 43,271
A photosensitive layer using a pyrylium-based compound described in Publication No. 69, or a photosensitive layer containing well-known inorganic photoconductive substances such as zinc oxide and cadmium sulfide dispersed in a resin, selenium, selenium- It is also possible to use a vapor-deposited film of tellurium or the like, or a film body made of an amorphous material containing silicon atoms.

Among these, a photoconductive member using a film made of an amorphous material containing silicon atoms as a photosensitive layer has a photoconductive layer, for example, a charge injection blocking layer, a photosensitive layer ( It has a structure in which a photoconductive layer) and a surface protection layer are sequentially laminated.

The charge injection blocking layer is made of, for example, amorphous silicon (a-3i) containing hydrogen atoms and/or halogen atoms, and as a substance governing conductivity, it is a substance in the periodic table No. Contains atoms of elements belonging to Group 1 or Group Ⅰ. The thickness of the charge injection blocking layer is preferably 0.01 to 10 μm, more preferably 0.05 to 8 μm, and most preferably 0.07 to 5 μm.

Instead of a charge injection blocking layer, for example Aj! ,0. .

A barrier layer made of an electrically insulating material such as S iog , S 1sNa or polycarbonate may be provided, or a charge injection blocking layer and a barrier layer may be used together.

The photosensitive layer contains, for example, a hydrogen atom and a halogen atom.
-3t, and optionally contains a substance controlling conductivity different from that used in the charge injection blocking layer. The thickness of the photosensitive layer is preferably 1 to 100 .mu.m, more preferably 1 to 80 .mu.m, most preferably 2 to 50 .mu.m.

The surface protective layer is composed of, for example, 5iCx, SiNx, etc., and the layer thickness is preferably 0.01 to 10 μm, more preferably 0.02 to 5 μm, and most preferably 0.04 to 5 μm.

In the present invention, in order to form a photoconductive layer etc. composed of a-3T, for example, a glow discharge method, a sputtering method,
Alternatively, a vacuum deposition method that requires various conventionally known discharge phenomena, such as an ion blating method, may be applied.

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited thereto.

A rigid SUS stainless steel sphere with a top diameter of 5.01 mm was processed to form the pseudo-conical irregularities shown in FIG. 6(A). Using this hard sphere, Figure 4 (A) and Figure 4 (B)
Using the apparatus shown in the figure, the surface of a cylindrical aluminum alloy cylinder (diameter: 80 fins, length: 3580 mm) was treated to form irregularities with hard ball trace depressions on the cylinder surface. The depth of the unevenness caused by the dents was adjusted to the desired shape by controlling the fall height H, and the pitch (density) of the dents was controlled by controlling the amount of rigid spheres used and the processing time. On the other hand, for comparison, irregularities by hard ball trace depressions were formed on the cylinder surface using the same apparatus as in the example except that a rigid perfect sphere made of SUS stainless steel with a diameter of 0.3 fi was used. When these surfaces were observed with an optical microscope, it was found that spherical trace depressions were formed all over the flat surface.

The thus obtained cylindrical surface-treated cylinder was introduced into a film forming chamber using a glow discharge method, and a film was formed thereon under the conditions shown in the table below to produce an electrophotographic photosensitive drum.

The resulting two photoreceptor drums were set in a Canon Laser Copier NP9030, and image exposure was performed on the original document using a Canon NA-7 test chart under normal conditions using a laser with a wavelength of 780 nm and a spot diameter of 80 μm. When the resulting images were observed, they were found to be excellent images with no interference fringes at all.

Next, when the original manuscript was replaced with a black and white silver halide photograph, the same procedure was performed, and it was found that the image was also excellent, with no interference fringes that could be discerned.

Finally, when we changed the original document to a halftone solid image with a reflection density of 0.3, which can detect interference fringes most sensitively, we performed the same procedure, and found that the interference fringes were almost discernible on the drum with the uneven surface of the present invention. Whereas I couldn't
For the drum with a perfectly spherical uneven surface, interference fringes were observed that were slight but clearly visible to the naked eye.

Daiarashi Group 1 A cylinder with a cylindrical surface was obtained in the same manner as in Example 1 except that the surface shape of the rigid sphere was changed as shown in Figure 6(B), and the same surface observation and image evaluation were performed. Good results equivalent to those of Example 1 were also obtained for the following items.

[Summary of effects of the present invention]

According to the surface-treated substrate member of the present invention, the surface treatment is performed without a cutting process that is likely to cause surface defects that impair desired usage characteristics. For example, when this substrate member is used as a support for a photoconductive member, A photoconductive member with excellent uniformity in film formation and uniformity in electrical, optical, and photoconductive properties can be obtained, and especially when used for electrophotographic sensitization, it can produce high-quality images with few image defects. In particular, when coherent light such as laser light is used, excellent images without interference fringes can be obtained.

[Brief explanation of the drawing]

FIGS. 1 and 2 are schematic diagrams showing the relationship between the rigid sphere and the base member that constitute the present invention. Sections 3 (A) to (B)
) is a typical surface shape and sectional view for explaining the surface shape of the hard sphere for surface treatment of the present invention. FIGS. 4A and 4B are a schematic cross-sectional view and a schematic vertical cross-sectional view of an apparatus for producing a substrate member having spherical traces according to the present invention. Figures 5 (A), (B) to (C) are cross-sectional views of a base member formed with typical spherical trace depressions according to the present invention. Figures 6(A) and 6(B) show the specific shape of the unevenness formed on the surface of the rigid sphere used in the embodiment of the present invention.
It is an explanatory view of dimensions. In each figure, l... Member for base body, 2... Surface of member for base body, 3... Rigid sphere, 4... Spherical trace depression, 11
... Aluminum cylinder, 12 ... Bearing, 1
3... Drive means, 14... Rotating container, 15... Rigid sphere, 16... Lip, 17... Shower pipe.

Claims (1)

[Scope of Claims] 1. The surface has irregularities formed by a plurality of spherical trace depressions, the shape of the irregularities due to the spherical trace depressions forms a continuous curve on the slope, and the slope converges at the apex of the depression. A base member for an electrophotographic photoreceptor, characterized in that it forms a discontinuous curve at one point. 2. The base member for an electrophotographic photoreceptor according to claim 1, wherein the uneven shape is formed by depressions having substantially the same curvature and width. 3. The surface has irregularities of a constant shape, and each convex part has a slope that forms a continuous curve in the cross section,
A plurality of rigid spheres forming a discontinuous curve in a concave portion where the slopes converge are allowed to naturally fall to form irregularities on the surface of the base member due to trace depressions of the rigid spheres. The shape of the unevenness due to the spherical trace depressions forms a continuous curve on the slope, and forms a discontinuous curve at one point at the apex of the depression where the slope converges. A method for manufacturing a base member for an electrophotographic photoreceptor.