JPH0476471B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) This invention relates to a method for manufacturing a photoreceptor for electrophotography, and in particular, it relates to a method for manufacturing a photoreceptor for electrophotography. The present invention relates to a method for manufacturing an electrophotographic photoreceptor by forming an adhered layer.

(Prior art) Photoreceptors for electrophotography are used in electronic copying machines, laser printers, etc.
It has been disclosed in various documents including Publication No. 170858. Recently, there has been a trend toward the use of functionally separated photoreceptors in which charge generation and charge transport are shared by each layer and manufactured in a laminated manner. It is provided with an adhesion layer such as a resin layer and a photosensitive layer provided thereon. A detailed explanation of the manufacture of the photoreceptor and the materials used therein will be omitted, but the substrate is made of suitable materials depending on the purpose, such as aluminum, and in the formation of the adhesion layer. Although it varies depending on the design of the photoreceptor, for example, a deposition liquid containing various resins such as polyester or a charge generating substance such as indium phthalocyanine in an organic solvent or the like is used.

Various methods have been proposed for manufacturing such electrophotographic photoreceptors. Among them, the dip coating method can be said to be one of the superior manufacturing methods when considering productivity, cost, quality of the photoreceptor after manufacturing, etc.

In this dip coating method, the substrate of an electrophotographic photoreceptor is immersed in a coating liquid for forming a resin layer as an undercoat layer, for example, and then the substrate is pulled up at a specified speed to coat the substrate surface with the coating liquid. It is applied. According to this method, the deposited liquid can be seamlessly formed on the surface of the substrate to a constant thickness, and photosensitive layers such as a charge generation layer and a charge transport layer can be further deposited on this resin layer. It is possible to sequentially stack layers using a liquid. Therefore, it can be said that this method is suitable for manufacturing a cylindrical electrophotographic photoreceptor.

Incidentally, the outer periphery of both ends of the base of an electrophotographic photoreceptor is usually subjected to conductive treatment, or various types of bumps are applied to maintain a constant distance between the base and, for example, a developing device. It is preferable that no adhesion layer, ie, a resin layer, a photosensitive layer, etc., be formed on this portion since it will come into contact with a pad or the like.

FIG. 4 is a perspective view schematically showing a preferred electrophotographic photoreceptor, in which band-shaped portions 11 at both ends of a cylindrical base 11 having openings at both ends are shown.
An adhesion layer 13 such as a resin layer or a photosensitive layer is formed in the area excluding areas other than a and 11b.

However, when manufacturing an electrophotographic photoreceptor using the above-mentioned dip coating method, generally one end of the base 11 having openings at both ends as shown in FIG. It is immersed in the adhering liquid up to a predetermined position.

When such a substrate 11 is used, since the substrate 11 is hollow, there is an advantage that the change in the liquid level of the adhered liquid before and after the substrate 11 is immersed in the adhered liquid is small, but if no countermeasure is taken. However, as shown in FIG. 6, there was a drawback that the coating liquid 13 was also applied to the immersed end of the substrate 11. Furthermore, when the base body 11 is immersed in the adherend liquid, the adherend liquid may also be applied to the inner surface (inside the cylinder) of the base body 11, causing the inner diameter dimension of the base body 11 to change. When such a dimensional change occurs, the base 1
It becomes impossible to insert a shaft for connection to a drive source for rotating the base body 11 into the inner surface of the base body 11.

In order to improve these drawbacks, various methods have been proposed in the past when using the dip coating method.

For example, according to the method proposed in JP-A No. 60-170858, after dip coating is completed, the coating liquid (coating film) on the edge of the substrate is coated before it dries. The paint film in this area is mechanically removed by rubbing a flexible plate. Further, if necessary, a solvent that dissolves the coating film is used in combination with the above-mentioned plate to remove the coating film.

In addition, according to a method proposed in Japanese Patent Application Laid-Open No. 60-168154, a substrate with one end closed is immersed in a deposited liquid from the other end to reduce the amount of deposited liquid that enters the inside of the substrate. The adhered liquid that has entered some areas is removed by the solvent that flows out from the nozzle.

Furthermore, in order to prevent the deposited liquid from penetrating the inner surface of the substrate, a jig as shown in FIG. 7 may be used. This jig consists of an upper end coating jig 17a and a lower end coating jig 17b, which are respectively provided at the openings at both ends of the base 11 via packings 15 such as O-rings, and these coating jigs are connected to each other at both ends of the base. It is provided with upper and lower coupling tools 19 for fixing to the substrate 11, and is intended to prevent the deposited liquid from entering into the interior of the substrate 11 by means of the upper and lower application jigs.

In addition, in the dip coating method, in order to obtain a uniform photoreceptor with good yield, changes in the surface of the deposited liquid before and after the substrate is immersed in the deposited liquid cannot be ignored. For this reason, as in the method disclosed in Japanese Unexamined Patent Publication No. 158456/1984, the level of the liquid to be adhered to is detected by a level detector before the substrate is immersed, and the height of the liquid level is always kept constant. ing. Alternatively, the height of the liquid level is always kept constant by causing the deposited liquid to overflow. This method covers a substrate that is cylindrical and has one end closed, or a substrate that has both ends closed with a jig as already explained using FIG. As in the case of immersion in liquid,
This is effective when the liquid level changes significantly before and after immersion.

(Problems to be Solved by the Invention) However, as mentioned above, conventional techniques such as mechanically removing unnecessary deposits on both ends of the substrate and removing deposits on the inner surface of the substrate using a solvent This method requires a removal process, and the solvent may also affect the deposited film that is necessary for the photoreceptor, increasing manufacturing costs and reducing reliability. There was a problem.

Furthermore, when using a base body with one end closed and a base body with both ends closed, it is certainly possible to reduce and prevent the adhered liquid from entering the inner surface of the base body.
There was a problem in that the level of the deposited liquid varied significantly before and after the substrate was immersed. Therefore, in order to cause the adhered liquid to overflow and maintain the level of the liquid at a constant level, the amount of overflow liquid must be increased, which results in an increase in the size of the apparatus.

Furthermore, when a jig as shown in FIG. 7 is actually used, the liquid adheres to the outer periphery of the end on the side where the substrate is immersed, so a step of removing this is necessary. Furthermore, the base 11 and the coating jigs 17a, 1
There were problems in that it was difficult to remove the coating jig because the adhered liquid entered between the coating and the 7b, and cleaning the coating jig after use was time-consuming and it was not easy to remove the seal. .

The purpose of this invention is to solve the above-mentioned problems,
A method for producing an electrophotographic photoreceptor in which an adhesion layer can be formed on the immersed end of the substrate and the inner periphery of the substrate without adhering the adhesion liquid to the substrate when the substrate is immersed in the adhesion liquid. Our goal is to provide the following.

(Means for Solving the Problems) In order to achieve this object, according to the method for manufacturing an electrophotographic photoreceptor of the present invention, a cylindrical substrate having openings at both ends is immersed in a coating liquid. When producing an electrophotographic photoreceptor by forming an adhesion layer on the substrate, the substrate has openings at both ends and the outer diameter of one end is substantially the same as the outer diameter of the aforementioned body. A stepped cylindrical part whose outer diameter other than the end portion is smaller than the inner diameter of the aforementioned base, and where the entire length of the portion where the inner diameter is smaller is longer than the entire length of the aforementioned base, is attached to one side of the aforementioned base. After fitting into the base body from the edge side of the base body, the abutting portion between the base body and the stepped cylindrical part is covered with adhesive tape over the mutual outer peripheral surfaces of the base body and the stepped cylindrical part, and then, The base body fitted with the stepped cylindrical portion is immersed in the deposited liquid from the one end edge side.

Note that during this immersion, the substrate is immersed in the liquid to a point where the other end of the substrate is partially exposed, and then the substrate is pulled up from the liquid at a specified speed. suitable. The stepped cylindrical portion may be made of metal or other suitable materials, but materials with excellent organic solvent resistance and low cost, such as polyethylene and polypropylene, may also be used. Furthermore, at least the inner surface of the stepped cylindrical portion is coated with, for example, polytetrafluoroethylene (hereinafter referred to as Teflon (trade name of DuPont)).
It is preferable to coat a material to which the liquid to be adhered is difficult to adhere, such as. Further, it is preferable to provide a taper on the inner circumferential surface of the stepped cylindrical portion on the end side where the outer diameter increases, in order to improve the flow of the deposited liquid when the substrate is pulled up after dip coating.

(Function) According to the method for manufacturing an electrophotographic photoreceptor of the present invention, the adhesive tape prevents the adhered liquid from entering the inner periphery of the substrate from the abutting portion of the substrate and the stepped cylindrical portion, and A region for preventing adhesion of adhered liquid is defined at the outer periphery of one end of the base body. Further, the stepped cylindrical portion prevents the deposited liquid from coming into contact with the inner peripheral portion of the substrate. For this reason, the coating is applied to an area extending from the outer periphery of the end (one end) on the side that is immersed in the liquid to be immersed in the coating liquid to the end (bottom) on this end side and then to the inner periphery of the substrate that has openings at both ends. It can prevent liquid from adhering. Furthermore, preventing the liquid from adhering to the outer peripheral portion of the other end of the substrate can be easily achieved by, for example, controlling the position of the substrate immersed in the liquid.

In addition, since a stepped cylindrical part is used in which the outer diameter of one end is substantially the same as the outer diameter of the base, the base with this stepped cylindrical part fitted looks like a Since its total length is the same as if it had been extended, when the substrate is pulled up from the deposited liquid, the flow of the deposited liquid at the lower end of the original substrate becomes better than when the stepped cylindrical portion is not used.

In addition, since a base body with open ends and a stepped cylindrical part with both ends open, that is, a pipe-shaped base body and a stepped cylindrical part, are used, the force required to immerse them in the deposited liquid is The volume of immersion is smaller than when dipping a substrate whose bottom end is blocked, and the volume of immersion is smaller than when dipping a substrate whose bottom end is blocked. Changes in liquid level height can be reduced.

Also, it is very easy to attach the stepped cylinder and the adhesive tape to the base and to remove them from the base.

In addition, by coating the inner surface of the stepped cylindrical part with Teflon, it becomes difficult for the adhered liquid to adhere to this surface, so it is easy to remove the adhered liquid adhering to the stepped cylindrical part after forming the adhered layer. It can be washed. or,
If the stepped cylindrical portion is made of polyethylene or the like, it is inexpensive and the covering member can be made disposable. Furthermore, by providing a taper in the stepped cylindrical portion, it is believed that the deposited liquid flows down uniformly when the substrate is pulled up after immersion, and a uniform deposited film can be obtained.

(Example) Hereinafter, an example of the method for manufacturing an electrophotographic photoreceptor of the present invention will be described with reference to FIGS. 1 to 3. Note that these drawings are merely shown schematically to the extent that the present invention can be understood, and the dimensions, shapes, and arrangement relationships of each component are not limited to the illustrated examples. Furthermore, in these figures, the same components are designated by the same reference numerals.

The present invention relates to a method for manufacturing an electrophotographic photoreceptor by immersing a cylindrical substrate in an adhering liquid to form an adhering layer on the substrate, and in this case, at least one end of the cylindrical substrate is A covering member for preventing adhesion of a liquid is provided in a region extending from the edge to the outer circumference and inner circumference of the base, and the base is immersed in the liquid from the end side where the cover member is provided. For example, it forms an undercoat layer, a charge generation layer, a charge transport layer, etc.

First Embodiment FIG. 1A is a cross-sectional view showing the basic structure of a cover member suitable for use in the electrophotographic photoreceptor manufacturing method of the present invention and the arrangement relationship between the cover member and the photoreceptor substrate. .

In FIG. 1A, reference numeral 11 indicates a cylindrical base having openings at both ends. Reference numeral 21 denotes a stepped cylindrical portion which is a part constituting the cover member, and in this case, it has openings at both ends, and the outer diameter dimension of one end 21a (dimension indicated by φ ₁ in FIG. 1A) is the same as that of the base 11. This end portion 21 has substantially the same outer diameter dimension as the outer diameter dimension of
The outer diameter dimensions of the cylindrical portions other than a (in Fig. 1A,
₂ ) is smaller than the inner diameter of the base body 11. Also, in this case, the stepped cylindrical part 2
1, the total length of the portion smaller than the inner diameter dimension of the base body 11 is made longer than the total length of the base body 11.
Further, 23 indicates a hanging part for hanging the base body and the stepped cylindrical part, and 31 indicates an adhesive tape which is a part of the cover member.

Further, in this stepped cylindrical portion 21, a portion of the cylindrical portion smaller than the inner diameter of the aforementioned base body is fitted into the inside of the aforementioned base body. Further, around the abutting portion between the edge of the base body and the end portion 21a of the stepped cylindrical portion, the end portion of the base body 11 and the end portion 21a of the stepped cylindrical portion are provided.
The above-mentioned adhesive tape 31 is pasted over the outer circumferential surfaces of the two to prevent the adhered liquid from entering through the gap between the abutting portions. As this adhesive tape, it is preferable to use a material with excellent solvent resistance such as polyimide or Teflon.
In this case, polyimide tape with adhesive (manufactured by Nitto Denko) was used.

FIG. 2 is an explanatory diagram schematically showing an example of a coating apparatus suitable for use in the dip coating method.

81 is a tank containing the deposited liquid, 82 is a deposited liquid overflow part, 83 is a pump for circulating the deposited liquid, 8
4 is a filter, 85 is a sub tank for adhered liquid, 86
is a stirrer for the deposited liquid, 87 is a deposited liquid supply pipe, 8
Reference numeral 8 indicates a diluent supply pipe for the deposited liquid, and reference numeral 89 indicates a substrate holder of a coating device for raising and lowering the substrate. The formation of an adhesion layer for manufacturing an electrophotographic photoreceptor will be explained with reference to this figure. It is clear that the method of the present invention can be realized not only by this coating device but also by using other suitable devices.

The base body 11 and cover member 21 (hereinafter abbreviated as the base body 11 etc.) as described above are fixed to the base body holding part 89 of the coating device via the hanging part 23. Next, the substrate 11 and the like are gently immersed from the end portion 21a side into the tank 81 containing the coating liquid. Although it varies depending on the design, it is usually 0.5 to 1 cm from the top of the base 11.
Immerse it to about the bottom level. Thereafter, by pulling up the substrate 11 and the like at a specified speed, it is possible to obtain an adhered layer of a certain thickness, such as a resin layer, a charge generation layer, or a charge transport layer. By changing the type of depositing liquid and performing the same operation, various deposited layers can be laminated. Thereafter, the adhesive tape 31 is peeled off and the stepped cylindrical portion is removed. No deposited film is formed on the inner surface of the base 11 of the photoreceptor obtained by such a method. Since no deposited film is formed on the upper end region of the substrate that is not immersed, the desired electrophotographic photoreceptor as already explained in FIG. 5 can be easily obtained.

In addition, as shown in FIG. 1B, by tapering the inner surface of the end 21a of the stepped cylindrical portion 21, it is possible to prevent the deposited liquid from being pulled up after immersing the substrate 11 in the deposited liquid. Since the flow (sag) is uniform, the thickness of the deposited film can be made uniform. Furthermore, if the photoreceptor is of the type described in this embodiment and shown in FIGS. 1A or 1B, the base 11 and the like can be easily made to stand on their own, thereby improving workability in manufacturing the photoreceptor.

Second Embodiment FIG. 3 is a sectional view showing a cover member and a base body for explaining a second embodiment of the present invention.

In addition to the same configuration as Example 1, this example has the following features:
An upper end fixing jig 33, which also serves as a part of the cover member, is provided between the stepped cylindrical portion 21 and the base 11 at the ends thereof on the opposite side from the side to be immersed in the liquid.
Furthermore, an adhesive tape 31 is pasted to cover the gap between the fixture 33 and the base 11. With this configuration, the fixing jig 33
The substrate 11 and the like can be immersed in the deposited liquid up to the vicinity of the upper end. The adherend layer formed by the dip coating method is usually thick at the beginning of coating and gradually becomes thinner, and the thickness becomes constant from about 1 to 4 cm away from the coating start position. Therefore, the adhesion layer that can actually be used as a photoreceptor is located closer to the center than 2 to 5 cm from the upper end. However, as in this example, if the deposited film is also formed on the fixing jig part, the film thickness will be uneven in this part, so the deposited film on the substrate should be kept at a constant thickness. It can be made into Therefore, in the past, it was not possible to use the photosensitive layer in a 3 to 6 cm portion of the total length of the photoreceptor substrate;
With this embodiment, it is possible to use the base up to the vicinity of both ends as a photoreceptor. This makes it possible to shorten the total length of the photoreceptor,
Furthermore, it is possible to downsize the device in which the photoreceptor is mounted.

Since the base body and cover member used in the first and second embodiments as described above both have a hollow structure, the base body 11 is placed in the tank 81 containing the coating liquid.
It is possible to reduce the change in the level of the deposited liquid in the tank when it is immersed or pulled up. Therefore, it is possible to reduce the amount of deposited liquid that overflows. As a result, the amount of circulation of the deposited liquid can be reduced, and it is also possible to prevent defects in the deposited layer due to bubbles in the deposited liquid caused by air entrainment in the piping.

Furthermore, by coating the inner surface of the stepped cylindrical part used in each of the above-mentioned Examples, the adherent liquid becomes difficult to adhere to this surface, so that the adherent liquid does not adhere to the stepped cylindrical part after the adherend layer is formed. The adhered liquid can be easily washed away. Furthermore, if the stepped cylindrical portion is made of polyethylene or the like, this is inexpensive and the cover member can be made disposable.

Furthermore, in each of the above-mentioned embodiments, the stepped cylindrical part is described as an integral cylindrical part, but the present invention can also be modified, for example, by dividing it into two parts at the stepped part, or by making it thinner toward the upper end. The shape and structure can be changed within the scope of the purpose.

Further, the present invention can be applied to a variety of substrate materials and coating liquid materials, including those conventionally used in electrophotographic photoreceptors.

Furthermore, the cover member according to the present invention can also be applied to the manufacture of products that require a structure similar to this electrophotographic photoreceptor.

(Effects of the Invention) As is clear from the above explanation, according to the method for manufacturing an electrophotographic photoreceptor of the present invention, the side of the cylindrical substrate having openings at both ends, which is immersed in the adhered liquid, It is possible to easily prevent the adhering liquid from adhering to the region extending from the outer periphery of the end (one end) to the bottom and inner periphery of this end. Furthermore, preventing the liquid from adhering to the outer periphery of the other end of the substrate can be easily achieved by controlling the position of the substrate immersed in the liquid. Therefore, a substrate having an adhesion layer only in necessary parts can be obtained without any post-treatment.

In addition, since a stepped cylindrical part whose outer diameter at one end is substantially the same as the outer diameter of the substrate is fitted to the substrate, it is possible to The flow of the deposited liquid at the lower end of the cylinder is better than when the stepped cylindrical part is not used. Therefore, the uniformity of the thickness of the adhered layer can be improved.

In addition, since the base body with both ends open and the stepped cylindrical part with both ends open are used, less force is required when immersing them in the adherend liquid, and the liquid level of the adherend liquid is lower. Since the change in height can be made small, the immersion device can also be made simple.

Further, since both the stepped cylindrical portion and the adhesive tape can be easily attached to and detached from the base, the photoreceptor can be manufactured easily.

[Brief explanation of drawings]

1A and 1B are cross-sectional views showing the arrangement relationship between a cover member and a photoreceptor substrate for explaining a first embodiment of the method for manufacturing an electrophotographic photoreceptor of the present invention, and FIG. 2 is a sectional view of the invention. 3 is an explanatory diagram of a second embodiment of the method for producing an electrophotographic photoreceptor according to the present invention, and FIG. 4 is a preferred embodiment of the method for producing an electrophotographic photoreceptor according to the present invention. FIG. 5 is a perspective view showing an example of a substrate for an electrophotographic photoreceptor; FIG. 6 is a perspective view showing a conventional photoreceptor after dip coating; FIG. 7 is a perspective view showing an example of a conventional dip coating jig. DESCRIPTION OF SYMBOLS 11... Base body, 21... Covering member (stepped cylindrical part), 23... Hanging part, 31... Covering member (adhesive tape), 33... (covering member) upper end fixing jig.

Claims (1)

[Scope of Claims] 1. When manufacturing an electrophotographic photoreceptor by immersing a cylindrical substrate having openings at both ends in an adhering liquid to form an adhering layer on the substrate, openings are provided at both ends. and the outer diameter of one end is substantially the same as the outer diameter of the base, and the outer diameter of the other end is smaller than the inner diameter of the base, and the inner diameter is smaller. After fitting the stepped cylindrical portion, the total length of which is longer than the total length of the base body, into the base body from one end edge side of the base body, the abutment portion between the base body and the stepped cylindrical portion is connected to the base body and the stepped cylindrical portion. An electronic device characterized in that the outer peripheral surfaces of the stepped cylindrical portions are covered with adhesive tape, and then the base body fitted with the stepped cylindrical portion is immersed in the adhered liquid from the one edge side. A method for manufacturing a photographic photoreceptor. 2. The method for manufacturing an electrophotographic photoreceptor according to claim 1, wherein the stepped cylindrical portion has an inner circumferential surface coated with polytetrafluoroethylene. 3. The method of manufacturing an electrophotographic photoreceptor according to claim 1 or 2, wherein the stepped cylindrical portion is made of polyethylene. 4. The electronic photograph according to any one of claims 1 to 3, wherein the stepped cylindrical portion has a tapered inner circumferential surface on the end side where the outer diameter increases. Method of manufacturing photoreceptor for use.