JP2020171877A - Washing method of substrate, and manufacturing method of electro-photographic photosensitive member - Google Patents

Abstract

To provide a washing method of a substrate capable of washing sufficiently a metal soap adhering onto the substrate, while suppressing corrosion of the substrate.SOLUTION: A washing method of a substrate includes the first washing step for washing an impact pressed substrate to which a metal soap adheres with an organic washing agent containing at least one kind selected from glycol ether and aliphatic alcohol as much as 10 mass% or more, and the second washing step for washing the substrate after the first washing step with an acidic or alkaline water-based cleaning agent.SELECTED DRAWING: None

Description

The present invention relates to a method for cleaning a substrate and a method for producing an electrophotographic photosensitive member.

An electrophotographic image forming apparatus is used in an image forming apparatus such as a copier and a laser beam printer. When manufacturing an electrophotographic photosensitive member used in an image forming apparatus, for example, an undercoat layer (sometimes called an intermediate layer) is formed on a conductive substrate such as aluminum, and then a photosensitive layer is formed. In many cases.
The electrophotographic photosensitive member generally has a layer structure in which a photosensitive layer is formed on a substrate. Further, as the conductive substrate, a conductive material formed into a cylindrical shape by non-cutting processing, impact press processing, or the like is used.

On the substrate for the electrophotographic photosensitive member (hereinafter, in some cases, simply referred to as “base”), deposits such as oil used in the process of producing the substrate are attached to the surface of the substrate. Therefore, when the substrate is used as a substrate in an electrophotographic photosensitive member, it is desirable to perform a cleaning treatment in advance to remove deposits.

Here, Patent Document 1 states that "after cleaning with a water-insoluble solvent, the water-insoluble solvent is replaced with the water-insoluble solvent and a rinsing solution compatible with water, and then the water-insoluble cleaning agent is used for cleaning. A cleaning method characterized by the above is disclosed.

Further, Patent Document 2 states, "The conductive substrate for an electrophotographic photosensitive member is immersed and washed in pure water, ion-exchanged water or surfactant-containing water, and rinsed with alcohol-containing pure water or ion-exchanged water under the action of ultrasonic waves. A method for cleaning a conductive substrate for an electrophotographic photosensitive member, which comprises treating and drying, is disclosed.

Japanese Unexamined Patent Publication No. 07-148472 Japanese Unexamined Patent Publication No. 05-204173

In impact press processing, which is one of the methods for molding a substrate, it is known that metal soap is used as a lubricant when processing slag or the like to form a substrate. If an attempt is made to clean the metal soap adhering to the substrate after this impact press working, the substrate may be corroded. Alternatively, the metal soap adhering to the substrate may not be sufficiently washed (for example, the amount of the metal soap adhering is 30 × 10 ^-3 mg / cm ² or less).
Therefore, the subject of the present invention is a cleaning method for cleaning the substrate with an organic cleaning agent containing at least one selected from glycol ether and an aliphatic alcohol in an amount of less than 10% by mass, or by using an organic cleaning agent. Compared with the cleaning method in which the amount of the metal soap adhering after cleaning the substrate exceeds 30 × 10 ^-3 mg / cm ^2, the metal soap adhering to the substrate is sufficiently applied while suppressing the corrosion of the substrate. To provide a method for cleaning a substrate to be cleaned.

Specific means for solving the above problems include the following aspects.

[1] A first cleaning step of cleaning the impact-pressed substrate to which the metal soap is attached with an organic cleaning agent containing at least 10% by mass or more of at least one selected from glycol ether and an aliphatic alcohol.
A second cleaning step of cleaning the substrate after the first cleaning step with an acidic or alkaline aqueous cleaning agent, and
A method for cleaning a substrate, including.
[2] The first cleaning step of cleaning the impact-pressed substrate to which the metal soap is attached with an organic cleaning agent until the amount of the metal soap attached is 30 × 10 ^-3 mg / cm ² or less.
A second cleaning step of cleaning the substrate after the first cleaning step with an acidic or alkaline aqueous cleaning agent, and
A method for cleaning a substrate, including.
[3] The method for cleaning a substrate according to [1] or [2], wherein the second cleaning step is a step of cleaning the substrate with an alkaline aqueous cleaning agent.
[4] The method for cleaning a substrate according to [3], wherein the pH of the alkaline aqueous cleaning agent at 25 ° C. is 9 or more and 12 or less.
[5] The method for cleaning a substrate according to any one of [1] to [4], wherein the liquid temperature of the organic cleaning agent is 60 ° C. or higher.
[6] The method for cleaning a substrate according to [5], wherein the liquid temperature of the organic cleaning agent is 80 ° C. or higher.
[7] The method for cleaning a substrate according to any one of [1] to [6], wherein the first cleaning step is performed under reduced pressure.
[8] The method for cleaning a substrate according to any one of [1] to [7], wherein the metal soap contains a metal stearic acid salt.
[9] The method for cleaning a substrate according to any one of [1] to [8], wherein the substrate is a cylindrical substrate.
[10] A cleaning step of cleaning the impact-pressed conductive substrate to which metal soap is attached by the substrate cleaning method according to any one of [1] to [9].
A photosensitive layer forming step of forming a photosensitive layer on the conductive substrate, and
A method for producing an electrophotographic photosensitive member, including.

According to the invention according to [1], [8] or [9], a cleaning method for cleaning the substrate with an organic cleaning agent containing at least one selected from glycol ether and an aliphatic alcohol in an amount of less than 10% by mass. Provided is a method for cleaning a substrate, which sufficiently cleans the metal soap adhering to the substrate while suppressing corrosion of the substrate.

According to the invention according to [2], as compared with the case of the cleaning method in which the amount of the metal soap adhered after cleaning the substrate with an organic cleaning agent exceeds 30 × 10 ^-3 mg / cm ² . Provided is a method for cleaning a substrate, which sufficiently cleans the metal soap adhering to the substrate while suppressing corrosion of the substrate.

According to the invention according to [3], as compared with the case where the second cleaning step is a step of cleaning the substrate with an acidic aqueous cleaning agent, the metal soap adhering to the substrate while suppressing corrosion of the substrate. A method of cleaning the substrate is provided which thoroughly cleans the substrate.

According to the invention according to [4], a substrate that sufficiently cleans the metal soap adhering to the substrate while suppressing corrosion of the substrate, as compared with the case where the pH of the alkaline aqueous cleaning agent at 25 ° C. exceeds 12. Cleaning method is provided.

According to the invention according to [5] or [6], as compared with the case where the liquid temperature of the organic cleaning agent is less than 60 ° C., the metal soap adhering to the substrate is sufficiently removed while suppressing the corrosion of the substrate. A method of cleaning the substrate to be cleaned is provided.

According to the invention according to [7], a method for cleaning a substrate that sufficiently cleans the metal soap adhering to the substrate while suppressing corrosion of the substrate, as compared with the case where the first cleaning step is performed under atmospheric pressure. Is provided.
According to the invention according to [10], a cleaning method for cleaning the substrate with an organic cleaning agent containing at least one selected from glycol ether and an aliphatic alcohol in an amount of less than 10% by mass, or an organic cleaning agent. A cleaning step of cleaning the conductive substrate by a cleaning method in which the amount of the metal soap adhered after cleaning the substrate exceeds 30 × 10 ^-3 mg / cm ² , and a photosensitive layer is formed on the conductive substrate. Compared with the case of the method for producing an electrophotographic photosensitive member including the step of forming a photosensitive layer, the electrophotographic photosensitive member provided with a substrate obtained by sufficiently cleaning the metal soap adhering to the substrate while suppressing corrosion of the substrate. A manufacturing method is provided.

It is a schematic cross-sectional view which shows an example of the layer structure of the electrophotographic photosensitive member manufactured by the manufacturing method which concerns on this embodiment. It is a schematic cross-sectional view which shows another example of the layer structure of the electrophotographic photosensitive member manufactured by the manufacturing method which concerns on this embodiment.

Hereinafter, embodiments of this embodiment will be described. These descriptions and examples exemplify the embodiments and do not limit the scope of the embodiments.

In the numerical range described stepwise in the present embodiment, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of the numerical range described stepwise in another stepwise. Good. Further, in the numerical range described in the present embodiment, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the embodiment.

In the present embodiment, each component may contain a plurality of applicable substances. When referring to the amount of each component in the composition in the present embodiment, if a plurality of substances corresponding to each component are present in the composition, the plurality of species present in the composition unless otherwise specified. Means the total amount of substances in.

-How to clean the substrate-
The method for cleaning the substrate according to the first embodiment is to use an organic cleaning agent containing at least 10% by mass or more of at least one selected from glycol ether and an aliphatic alcohol on the impact-pressed substrate to which the metal soap is attached. It includes a first cleaning step for cleaning and a second cleaning step for cleaning the substrate after the first cleaning step with an acidic or alkaline aqueous cleaning agent. The method for cleaning the substrate according to the first embodiment may include other steps.

In impact press processing, which is one of the methods for molding a substrate, metal soap is used as a lubricant when processing slag or the like to form a substrate. Therefore, metal soap is attached to the substrate after the impact press processing.

As one of the methods for removing the metal soap adhering to the substrate after the impact press working, a method for cleaning the substrate with only a strongly alkaline aqueous solution (for example, pH 12 or higher) is known. However, in this method, the metal soap adhering to the substrate is removed, and the substrate tends to be corroded by the strongly alkaline aqueous solution.
Further, as another method for removing the metal soap adhering to the substrate after impact press processing, a method for cleaning the substrate only with an organic cleaning agent such as alcohol is also known. However, with this method, it is difficult to sufficiently remove the metal soap adhering to the substrate (for example, the amount of the metal soap adhering is 30 × 10 ^-3 mg / cm ² or less).

On the other hand, the method for cleaning the substrate according to the first embodiment provides a method for cleaning the substrate, which includes the above steps to clean the metal soap adhering to the substrate while suppressing corrosion of the substrate. This factor is not always clear, but it is presumed as follows.

In the method for cleaning a substrate according to the first embodiment, an organic cleaning agent containing at least 10% by mass or more of at least one selected from glycol ether and an aliphatic alcohol in the first cleaning step (hereinafter, "specific organic solvent"). Also referred to as) to wash the substrate. Glycol ethers and aliphatic alcohols tend to have a solubility parameter (hereinafter, also referred to as “SP value”) closer to that of metal soaps, as compared with organic solvents such as paraffinic hydrocarbons. That is, glycol ethers and aliphatic alcohols tend to have a high affinity for metal soaps. Therefore, by performing the first cleaning step using the specific organic solvent, most of the metal soap adhering to the substrate tends to be removed without corroding the substrate. Then, in the subsequent second cleaning step, the substrate after the first cleaning step is washed with an acidic or alkaline aqueous cleaning agent. In this second cleaning step, since the amount of metal soap adhering to the substrate is small, the substrate tends to be removed before it corrodes. As a result, it is considered that the metal soap adhering to the substrate can be sufficiently washed while suppressing the corrosion of the substrate.

The method for cleaning the substrate according to the second embodiment is to use an organic cleaning agent on the impact-pressed substrate to which the metal soap is attached until the amount of the metal soap adhered is 30 × 10 ^-3 mg / cm ² or less. It includes a first cleaning step of cleaning and a second cleaning step of cleaning the substrate after the first cleaning step with an acidic or alkaline aqueous cleaning agent. The method for cleaning the substrate according to the second embodiment may include other steps.

The method for cleaning the substrate according to the second embodiment provides a method for cleaning the substrate, which comprises the above steps to clean the metal soap adhering to the substrate while suppressing corrosion of the substrate. This factor is not always clear, but it is presumed as follows.

In the method for cleaning the substrate according to the second embodiment, in the first cleaning step, the substrate is cleaned with an organic cleaning agent until the amount of the metal soap adhered is 30 × 10 ^-3 mg / cm ² or less. .. That is, most of the metal soap adhering to the substrate tends to be removed. At this time, since an organic cleaning agent is used as the cleaning agent, corrosion of the substrate tends to be suppressed. Then, in the subsequent second cleaning step, the substrate after the first cleaning step is washed with an acidic or alkaline aqueous cleaning agent. In this second cleaning step, since the amount of metal soap adhering to the substrate is small, it tends to be able to be removed before the substrate is corroded. As a result, it is considered that the metal soap adhering to the substrate can be sufficiently washed while suppressing the corrosion of the substrate.

Hereinafter, the method for cleaning the substrate according to the first embodiment and the second embodiment are also collectively referred to as "method for cleaning the substrate according to the present embodiment". However, the example of the method for cleaning the substrate of the present invention may be any method for cleaning the substrate that corresponds to either one of the methods for cleaning the substrate according to the first embodiment and the second embodiment.

Hereinafter, the method for cleaning the substrate according to the present embodiment will be described in detail.

[Hypokeimenon]
The substrate according to this embodiment is an impact-pressed substrate. Hereinafter, the impact-pressed substrate is also simply referred to as "base".
Impact press working is a processing method in which a material such as a metal block is placed in a female mold, and the material is impacted by hitting the material through the male mold to form a substrate along the male mold.

The substrate may be a substrate whose inner diameter, outer diameter, cylindricity, roundness, etc. are adjusted by one or a plurality of ironing operations with respect to the substrate formed by impact press processing. Further, the substrate may be one in which both ends of the substrate in the ironing direction are cut off after the ironing process and further end face treatment is applied.

The substrate is preferably a cylindrical substrate from the viewpoint of manufacturing the substrate by impact press working.

The material of the substrate is not particularly limited as long as it can be molded by impact press working. The material of the substrate is preferably composed of, for example, aluminum, and more preferably made of a metal containing aluminum (aluminum or an aluminum alloy). Examples of the aluminum alloy constituting the substrate include aluminum alloys containing Si, Fe, Cu, Mn, Mg, Cr, Zn, and Ti in addition to aluminum. The aluminum alloy constituting the substrate is preferably a so-called 1000 series alloy, and the aluminum content (mass ratio) is preferably 99.5% or more from the viewpoint of processability, conductivity, and corrosion resistance, and 99.6. % Or more is more desirable. The substrate may be conductive, i.e. volume resistivity less than 10 ¹³ Ωcm.

Before the first cleaning step, the substrate according to the present embodiment has the metal soap used as a lubricant in the impact processing adhered to it.
The metal soap may be used alone or in combination of two or more.
Metal soap is a fatty acid metal salt in which a fatty acid and a metal are combined.
Examples of the fatty acid metal salt include metal salts of fatty acids having 10 or more and 25 or less carbon atoms (preferably 12 or more and 22 or less). Examples of the metal salt of fatty acid having 10 or more and 25 or less carbon atoms include a metal salt of stearic acid, a metal salt of palmitic acid, a metal salt of lauric acid, a metal salt of oleic acid, a metal salt of linoleic acid, and a metal of ricinoleic acid. Examples include salt. Examples of the metal in the fatty acid metal salt include a divalent metal.
Examples of the metal in the fatty acid metal salt include magnesium, calcium, aluminum, barium, and zinc. Among these, zinc is preferable from the viewpoint of preferably obtaining a substrate by impact processing.

Among the above, the fatty acid metal salt preferably contains at least one selected from a metal salt of stearic acid and a metal salt of lauric acid from the viewpoint of preferably obtaining a substrate by impact processing, and the metal of stearic acid. It is more preferable to contain a salt, and even more preferably to contain zinc stearate.

On the other hand, when the metal soap contains a stearin metal salt, the stearic acid metal salt tends to adhere strongly to the substrate, and it tends to be difficult to sufficiently clean the metal soap. According to the present embodiment, by using the method for cleaning the substrate according to the present embodiment, even in an impact-pressed substrate to which a metal soap containing a metal stearic acid salt is attached, the substrate can be subjected to while suppressing corrosion of the substrate. The attached metal soap can be sufficiently washed.

The impact-pressed substrate is machined by other molding methods (for example, a plastic working method such as an extrusion method or a drawing method, or a machining method for further improving the accuracy of the substrate obtained by the plastic working method. There are different features in appearance compared to the substrate formed by the method, grinding method, deep drawing method, ironing method, etc.).
For example, impact press working tends to have a high working rate. Therefore, in the impact-pressed substrate, the crystal grains are made finer, and streaky portions that are thinly stretched in the axial direction are formed. From this appearance feature, it can be determined that the substrate is impact-pressed.

Further, for example, the impact-pressed substrate generally becomes high hardness (for example, 45 HV or more) by work hardening. Therefore, the impact-pressed substrate has a higher hardness than, for example, a substrate obtained by cutting the surface of an aluminum tubular tube (bare tube). From this difference in hardness, it can be determined that the substrate is impact-pressed. Specifically, for example, the surface hardness of the impact-pressed substrate is 45 HV or more and 60 HV or less.
The surface hardness (Vickers hardness) of the substrate is determined by pushing an indenter from the surface of a metal tubular body using a Vickers hardness tester (trade name: MVK-HVL, manufactured by Akashi), pushing load: 1 kgf, pushing time: 20. Measure based on the measurement condition of seconds. The measurement points are 12 points in total, 4 points in the circumferential direction and 3 points in the axial direction for each sample. In the present embodiment, the outer peripheral surface hardness of the metal tubular body is determined as the average value of the hardness measured at the above 12 points.

[First cleaning process]
In the first cleaning step in the first embodiment, the impact-pressed substrate to which the metal soap is attached is cleaned with an organic cleaning agent containing at least 10% by mass or more selected from glycol ether and an aliphatic alcohol. To do.

In the first cleaning step in the second embodiment, the impact-pressed substrate to which the metal soap is attached is washed with an organic cleaning agent until the amount of the metal soap adhered is 30 × 10 ^-3 mg / cm ² or less. To do. The amount of the metal soap adhered is preferably 25 × 10 ^-3 mg / cm ² or less, preferably 20 × 10 from the viewpoint of sufficiently cleaning the metal soap adhering to the substrate while further suppressing the corrosion of the substrate. more preferably ^-3 mg / cm ² or less, further preferably 15 × ¹⁰ -3 mg / cm ² or less. The amount of metal soap adhered is preferably close to 0 mg / cm ² .

The fact that the amount of metal soap adhering to the substrate after the first cleaning is 30 × 10 ^-3 mg / cm ² or less means that most of the metal soap adhering to the surface of the substrate has been removed. Represent.

The abundance of the metal soap after the first cleaning can be determined by the following procedure.
First, the mass W ₀ of the slag before impact press working is measured in advance. Next, a lubricant is applied to the slag and impact press processing is performed. After the impact press working, the mass W ₁ of the substrate is measured again. The difference ΔW (= W ₁ −W ₀ ) of the obtained mass is defined as the amount of metal soap adhered to the substrate after the first cleaning step.

In the method for cleaning the substrate according to the second embodiment, as a method in which the amount of metal soap adhered after the first cleaning step is within the above range, for example, an organic cleaning agent is a specific organic cleaning agent described later. Examples thereof include a method of setting the amount of metal soap used in impact press processing within the above range in advance. However, the type of the organic cleaning agent is not particularly limited as long as the amount of the metal soap adhered after the first cleaning step can be within the above range.

≪Organic cleaning agent≫
In the first cleaning step according to the first embodiment, in addition to cleaning the substrate with the specific organic cleaning agent described later, the substrate may be further cleaned with the organic cleaning agent.
In the first cleaning step according to the second embodiment, the substrate is cleaned with an organic cleaning agent.

An organic cleaning agent is a cleaning agent containing an organic solvent as a main component. Here, the term "main component" means, for example, that when the organic cleaning agent contains an organic solvent and water, the ratio of the organic solvent to the total amount of the organic cleaning agent is larger than the ratio of water to the total amount of the organic cleaning agent. Represents a large number of cases. The organic cleaning agent preferably does not contain water.

The organic cleaning agent is not particularly limited as long as it can be washed until the amount of metal soap adhered is 30 × 10 ^-3 mg / cm ² or less, and a known organic solvent may be applied.
Examples of the organic cleaning agent include halogen-based solvents (methylene chloride, 1,1,1-trichloroethane, trichloroethylene, etc.), silicone-based solvents, paraffin-based hydrocarbons, glycol ethers described below, aromatic hydrocarbons described below, and described below. Examples thereof include aliphatic alcohols and alcohols other than the aliphatic alcohols described later.

The organic cleaning agent may be a specific organic cleaning agent described later.
The organic cleaning agent may be used alone or in combination of two or more.

≪Specific organic cleaning agent≫
In the first cleaning step according to the first embodiment, the substrate is cleaned with a specific organic cleaning agent.
In the first cleaning step according to the second embodiment, the substrate may be cleaned with a specific organic cleaning agent.

The specific organic cleaning agent refers to an organic cleaning agent containing at least one selected from glycol ether and an aliphatic alcohol in an amount of 10% by mass or more based on the total amount of the organic cleaning agent.

As the specific organic cleaning agent, at least one selected from glycol ether and fatty alcohol is used as the specific organic cleaning agent from the viewpoint of sufficiently cleaning the metal soap adhering to the substrate while further suppressing the corrosion of the substrate. It is preferably contained in an amount of 10% by mass or more, 30% by mass or more and 100% by mass or less, and more preferably 50% by mass or more and 100% by mass or less with respect to the total amount.

When the specific organic cleaning agent contains both glycol ether and an aliphatic alcohol, the total amount of the glycol ether and the aliphatic alcohol is 10% by mass or more based on the total amount of the organic cleaning agent.
When the specific organic cleaning agent contains two or more kinds of glycol ethers or aliphatic alcohols, the total amount of the two or more kinds of glycol ethers or aliphatic alcohols is 10% by mass or more based on the total amount of the organic cleaning agents. is there.

(Glycol ether)
The glycol ether may be a dialkyl glycol ether in which the hydroxy groups at both ends of the glycol are ether-bonded to an alkyl group, or a monoalkyl glycol ether in which one end of the glycol is ether-bonded to an alkyl group. Glycol ethers may be used alone or in combination of two or more.

The structures of glycols, monoalkyl glycol ethers and dialkyl glycol ethers are as shown below.
-Glycol (HO-L ^1- (OL ² ) n-OH)
L ¹ and L ² each independently represent a hydrocarbon group, and n represents 0 or an integer of 1 or more and 20 or less.
-Monoalkyl glycol ether (R ^1- L ^1- (OL ² ) n-OH)
R ¹ represents an alkyl group, L ¹ and L ² each independently represent a hydrocarbon group, and n represents 0 or an integer of 1 or more and 20 or less.
-Dialkyl glycol ether (R ² -OL ^1- (OL ² ) n-O-R ³ )
R ³ and R ² each independently represent an alkyl group, L ¹ and L ² each independently represent a hydrocarbon group, and n represents 0 or an integer of 1 or more and 20 or less.

Examples of glycols forming glycol ethers include aliphatic glycols, aromatic glycols, and alicyclic glycols. Among the above, the glycol is preferably an aliphatic glycol from the viewpoint of further enhancing the detergency of the organic cleaning agent for metal soap.

The aliphatic glycol is not particularly limited, and examples thereof include an aliphatic glycol having 2 or more and 20 or less carbon atoms. Examples of aliphatic glycols having 2 to 20 carbon atoms include 4-oxa-2,6-heptanediol, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, and 1,3. -Butanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, 1,3-propylene glycol, 1,10-decanediol, 1,12-dodecanediol, Examples thereof include 1,18-octanedecadiol and 1,20-icosandiol.

Examples of the alkyl ether chain in the glycol ether include linear or branched alkyl ether chains having 1 to 20 carbon atoms (-OR and R represent alkyl groups having 1 to 20 carbon atoms). Glycol ether having.

Specifically, the linear alkyl ether chain includes a methyl ether group, an ethyl ether group, an n-propyl ether group, an n-butyl ether group, an n-pentyl ether group, an n-hexyl ether group, and an n-heptyl ether group. n-octyl ether group, n-nonyl ether group, n-decyl ether group, n-decyl ether group, n-dodecyl ether group, n-hexadecyl ether group, n-octadecyl ether group, n-icosyl ether group, etc. Can be mentioned.

Specific examples of the branched alkyl ether chain include an isopropyl ether group, an isobutyl ether group, a sec-butyl ether group, a tert-butyl ether group, an isopentyl ether group, a neopentyl ether group, a tert-pentyl ether group, and an isohexyl ether group. , Sec-hexyl ether group, tert-hexyl ether group, isoheptyl ether group, sec-heptyl ether group, tert-heptyl ether group, isooctyl ether group, sec-octyl ether group, tert-octyl ether group, isononyl ether Examples thereof include a group, a sec-nonyl ether group, a tert-nonyl ether group, an isodecyl ether group, a sec-decyl ether group and a tert-decyl ether group.

The glycol ether may contain isomers and the like generated in the manufacturing process as long as the metal soap adhering to the substrate can be sufficiently washed while suppressing the corrosion of the substrate. For example, when dipropylene glycol monomethyl ether is used as the glycol ether, 2- (2-hydroxy-propoxy) -propane-1-ol, 2- (2-hydroxy-1-methyl-ethoxy) -propane-1-ol, etc. Structural isomers may be contained.

The glycol ether may be a commercially available product or a synthetic product. In the case of a commercial product, as a commercial product which is a specific organic cleaning agent containing 10% by mass or more of glycol ether, for example, Fine Top S130 manufactured by Kuraray Co., Ltd .; HC-FX70 manufactured by Tosoh Co., Ltd .; JXTG Energy Co., Ltd. NS-100R; MK-2, MK20, MK-30, etc. manufactured by Musashi Techno Chemical Co., Ltd. can be mentioned.

(Alphatic alcohol)
The aliphatic alcohol may be a monohydric alcohol or a polyhydric alcohol. The aliphatic alcohol is not particularly limited as long as it is an alcohol having an aliphatic chain, and may be an acyclic aliphatic alcohol or an alicyclic alcohol. The aliphatic alcohol may be used alone or in combination of two or more.

The aliphatic alcohol is preferably, for example, an aliphatic alcohol having 10 or more and 150 or less carbon atoms.

As the acyclic aliphatic alcohol, saturated aliphatic alcohol, unsaturated aliphatic alcohol and the like are used. Examples of the acyclic saturated aliphatic alcohol include decyl alcohol, undecyl alcohol, dodecyl alcohol (lauryl alcohol), tridecyl alcohol, tetradecyl alcohol, hexadecyl alcohol, octadecyl alcohol, nonadecil alcohol and tetracosenyl alcohol. And so on. Acyclic unsaturated aliphatic alcohols include, for example, decenyl alcohol, dodecenyl alcohol, tridecenyl alcohol, pentadecenyl alcohol, oleyl alcohol, tetracosenyl alcohol, gadrail alcohol and linoleyl. Alcohol and the like can be mentioned.

As the alicyclic alcohol, a monocyclic aliphatic alcohol, a compound ring aliphatic alcohol and the like are used. Examples of the monocyclic aliphatic alcohol include octylcyclohexyl alcohol, dodecylcyclohexylalcohol, nonylcyclohexylalcohol and stearylcyclohexylalcohol. Examples of the dicyclic aliphatic alcohol include adamantyl alcohol and dicyclohexyl alcohol.

The aliphatic alcohol may be a commercial product or a synthetic product.
In the case of a commercially available product, examples of the commercially available product which is a specific organic cleaning agent containing 10% by mass of an aliphatic alcohol include HC-AW7000 manufactured by Tosoh Corporation.

(Other organic cleaning agents)
The specific organic cleaning agent is an organic cleaning agent other than glycol ether and an aliphatic alcohol (hereinafter, also referred to as “other organic cleaning agent”) in an amount of less than 90% by mass based on the total amount of the organic cleaning agent. May be included in. The content of the other organic cleaning agents is preferably 0% by mass, that is, not contained in the total amount of the organic cleaning agents.

The other organic cleaning agents are not particularly limited, and known organic solvents may be applied. Other organic cleaning agents include, for example, halogen-based solvents (methylene chloride, 1,1,1-trichloroethane, trichlorethylene, etc.), silicone-based solvents, paraffin-based hydrocarbons, aromatic hydrocarbons, glycol ethers described later, and the like. Can be mentioned.
Among the above, the other organic cleaning agent is preferably a paraffinic hydrocarbon from the viewpoint of safety and low environmental load.

(Characteristics of specific organic cleaning agents)
The SP value of the specific organic cleaning agent is not particularly limited, but is preferably a value close to the SP value of the metal soap. When the SP value of the specific organic cleaning agent and the SP value of the metal soap are close (for example, the absolute value of the difference between the two SP values is 4 or less), the compatibility between the two tends to increase, and the specific organic cleaning for the metal soap tends to increase. It is considered that the detergency of the agent can be further improved.

The SP value according to the present embodiment means a value calculated by Fedor's method. Specifically, the solubility parameter (SP value) is, for example, Polymer. Eng. Sci. , Vol. 14, p. Based on the description of 147 (1974), the SP value is calculated by the following formula. As the solubility parameter (SP value), (cal / cm ³ ) ^1/2 is adopted as the unit, but the unit is omitted according to the practice and is expressed dimensionlessly.
Formula: SP value = √ (Ev / v) = √ (ΣΔei / ΣΔvi)
Ev: Evaporation energy (cal / mol)
v: Molar volume (cm ³ / mol),
Δei: Evaporative energy of each atom or atomic group Δvi: Molar volume of each atom or atomic group)

(Method for cleaning the substrate in the first step)
The method for cleaning the substrate in the first step according to the present embodiment is not particularly limited as long as it is a method for cleaning the substrate using an organic cleaning agent. Examples of the method for cleaning the substrate in the first step include the methods shown below.

(1) A pressing cleaning method in which an organic cleaning agent is attached to a cleaning member such as a brush, and the cleaning member to which the organic cleaning agent is attached is pressed against a substrate.
(2) A dipping cleaning method in which the substrate is immersed in a cleaning tank containing an organic cleaning agent.
(3) A spray cleaning method in which an organic cleaning agent is sprayed onto a substrate by spraying, showering, or the like.
(4) A high-pressure cleaning method in which a jet nozzle is used to inject a high-pressure organic cleaning agent.
(5) A vacuum vapor method in which an organic cleaning agent is boiled under vacuum and the substrate is rinsed with steam.

Among the above, the substrate cleaning method in the first step is selected from the group consisting of a pressing cleaning method, a high-pressure cleaning method, a dipping cleaning method and a vacuum vapor method from the viewpoint of efficient cleaning of the substrate and cost. It is preferable to include at least one cleaning method, more preferably at least one selected from the group consisting of the pressing cleaning method and the immersion cleaning method, and further preferably to include the immersion cleaning method.

The method for cleaning the substrate may be an embodiment in which only one cleaning method is used to clean the substrate, or a mode in which two or more cleaning methods are used in combination to clean the substrate.

The immersion cleaning includes, for example, a simple immersion in which the substrate is simply immersed in a cleaning tank, a heating immersion in which the substrate is immersed while heating, an ultrasonic immersion in which the substrate is immersed while applying ultrasonic waves, an organic cleaning agent circulated by a pump or the like. Circulation immersion, injecting inert gas such as nitrogen gas and immersing while diffusing organic cleaning agent by jet flow, bubbling immersion, immersing the cleaning tank while shaking and rotating at least one, shaking rotation immersion, depressurization Examples thereof include vacuum immersion for immersion underneath.

Among the above, from the viewpoint of increasing the detergency of the organic cleaning agent for metal soap, the method for cleaning the substrate in the first step includes bubbling immersion, shaking rotation immersion, warming immersion, ultrasonic immersion and vacuum immersion. It is preferable to include at least one cleaning method selected from the group, and it is more preferable to include at least one cleaning method selected from the group consisting of warm immersion, ultrasonic immersion and vacuum immersion.

In the case of the immersion cleaning, a method may be used in which a plurality of cleaning tanks are provided according to the amount of metal soap adhering to the substrate and the immersion cleaning is performed in sequence. In this case, the plurality of cleaning tanks are composed of multiple stages, and the cleaning process may be performed by gradually changing the components and concentrations of the cleaning agent from the first cleaning tank in which the substrate is immersed to the last cleaning tank. preferable.

In the case of the immersion cleaning, the time of immersion in the cleaning tank (cleaning time) may be appropriately set according to the number of cleaning tanks, the amount of metal soap adhering to the substrate, and the like. From the viewpoint of detergency, the longer the cleaning time, the more preferable. On the other hand, from the viewpoint of cost, the cleaning time is preferably short. For example, the washing time is preferably 30 seconds to 10 minutes, and more preferably 1 minute to 5 minutes. When cleaning using a plurality of cleaning tanks, the cleaning time means the total cleaning time in each cleaning tank.

The liquid temperature of the organic cleaning agent is not particularly limited and may be appropriately set according to the properties of the organic cleaning agent to be used. The liquid temperature of the organic cleaning agent is, for example, preferably 60 ° C. or higher, more preferably 70 ° C. or higher, and more preferably 80 ° C. or higher, from the viewpoint of further enhancing the cleaning property of the organic cleaning agent with respect to metal soap. It is more preferable to have. The upper limit of the liquid temperature of the organic cleaning agent is, for example, preferably 100 ° C. or lower, more preferably 95 ° C. or lower, and further preferably 90 ° C. or lower.

The first cleaning step may be performed under atmospheric pressure, reduced pressure, or pressurized pressure. From the viewpoint of further improving the detergency of the organic cleaning agent for metal soap, the liquid temperature of the organic cleaning agent is set to a temperature equal to or higher than the boiling point, so that the first cleaning step is performed under reduced pressure (for example, -100 kPa (10 torr) or more). It is preferably carried out under reduced pressure of −88 kPa (100 torr) or less). From the viewpoint of cleaning cost, it is preferable that the first cleaning step is performed under atmospheric pressure.

[Second cleaning process]
The method for cleaning the substrate according to the present embodiment includes a second cleaning step.
In the second cleaning step, the substrate after the first cleaning step is cleaned with an acidic or alkaline aqueous cleaning agent.

≪Water-based cleaning agent≫
In the second cleaning step according to the present embodiment, the substrate after the first cleaning step is cleaned with an aqueous cleaning agent. Water-based cleaning agents are acidic or alkaline.

An aqueous cleaning agent is a cleaning agent whose main component is an aqueous solution in which a water-soluble substance is dissolved in water. Here, the term "main component" means that, for example, when the water-based cleaning agent contains an organic solvent and the aqueous solution, the ratio of the aqueous solution to the total amount of the water-based cleaning agent is larger than the ratio of the organic solvent to the total amount of the water-based cleaning agent. Represents a case.

(Acid water-based cleaning agent)
Acidic aqueous cleaning agents include sulfuric acid, trifluoromethanesulfonic acid, hydrochloric acid, perchloric acid, nitrate, tetrafluoroboric acid, acetic acid, trifluoroacetic acid, and solid acid (citrate, carbonic acid, oxalic acid, phosphoric acid, boric acid). , Hypochloric acid, etc.) dissolved in an aqueous solution.

The pH of the acidic aqueous cleaning agent at 25 ° C. is preferably 1 or more and 5 or less, more preferably 1.5 or more and 5 or less, and 2 or more and 5 or less from the viewpoint of further suppressing corrosion of the substrate. It is more preferable to have.

(Alkaline water-based cleaning agent)
As an alkaline aqueous cleaning agent, alkaline substances (hydroxide salts such as sodium hydroxide, potassium hydroxide and cesium hydroxide; carbonates such as sodium hydrogen carbonate, sodium carbonate, potassium carbonate and cesium carbonate; ammonia, pyridine, etc. Examples thereof include an aqueous solution in which triethylamine, guanidine, organic bases such as 1,8-diazabicyclo- [5.4.0] -7-undecene, etc.) are dissolved. Among the above, the alkaline aqueous cleaning agent preferably contains an aqueous solution in which one or more alkaline substances selected from the group consisting of hydroxide salts and carbonates are dissolved, and is an aqueous solution in which the hydroxide salt is dissolved. It is more preferable to include.

The pH of the alkaline aqueous cleaning agent at 25 ° C. is preferably 9 or more and 12 or less, more preferably 9 or more and 12.5 or less, and 10 or more and 12 or less from the viewpoint of more efficiently cleaning the substrate. Is more preferable.

The second cleaning step is preferably a step of cleaning the substrate with an alkaline aqueous cleaning agent from the viewpoint of sufficiently cleaning the metal soap adhering to the substrate while further suppressing the corrosion of the substrate.

(Surfactant)
The water-based cleaning agent according to the present embodiment may further contain a surfactant.
Surfactants include nonionic surfactants such as polyoxyethylene alkylphenyl ether, polyoxyethylene polyoxypropylene block copolymer type and nonylphenol polyoxyethylene ether, alkylbenzenes, higher alcohols, α-olefin sulfates and cay. It is preferable to use an anionic surfactant such as an oxidate such as acid, phosphoric acid and carbonic acid.

The concentration of the surfactant in the aqueous cleaning agent is, for example, preferably 0.1% by mass or more and 0.5% by mass or less, and more preferably 0.2% by mass or more and 0.4% by mass or less.

(Method of cleaning the substrate in the second step)
Examples of the method for cleaning the substrate in the second step include the same cleaning method as the method for cleaning the substrate using the above-mentioned organic cleaning agent.

[Cleaning agent removal process]
The method for cleaning the substrate according to the present embodiment may include a cleaning agent removing step after each of the first cleaning step and the second cleaning step.
In the cleaning agent removing step, the organic cleaning agent or the water-based cleaning agent adhering to the substrate after each step is cleaned. Hereinafter, the organic cleaning agent and the water-based cleaning agent are also collectively simply referred to as "cleaning agent". Including the cleaning agent removing step, the cleaning agent adhering to the substrate can be removed.
The method for removing the cleaning agent is not particularly limited, and a known method for removing the cleaning agent may be applied. For example, in the cleaning agent removing step, from the viewpoint of enhancing the removing property of the cleaning agent, a solvent (water or organic solvent) in the cleaning agent solution used in each step or a solvent having a high affinity with the solvent in the cleaning agent solution is used. It is preferable to remove the cleaning agent.

[Drying process]
The method for cleaning the substrate according to the present embodiment may include a drying step after each of the first cleaning step and the second cleaning step. When the method for cleaning the substrate according to the present embodiment includes the cleaning agent removing step, the drying step is preferably performed after the cleaning agent removing step.
In the drying step, the cleaning agent or solvent adhering to the substrate after each step is dried and removed. The drying method is not particularly limited, and a known drying method may be applied. For example, examples of the drying method include a warm pure water drying method in which the substrate is immersed in heated pure water and then the substrate is pulled up to dry the substrate.

[Other processes]
The substrate cleaning method according to the present embodiment includes, in addition to the first cleaning step, the second cleaning step, the cleaning agent removing step, and the drying step, other steps such as a pretreatment step, an intermediate treatment step, and a posttreatment step. (Hereinafter, also simply referred to as “other steps”) may be included. For example, the pretreatment step may include a foreign matter removing step of removing solid foreign matter and the like adhering to the substrate in advance.

By the above steps, the impact-pressed substrate to which the metal soap is attached can be washed. As described above, the method for cleaning the substrate according to the present embodiment has been described, but the method for cleaning the substrate according to the present embodiment is not limited to this.

-Manufacturing method of electrophotographic photosensitive member-
The method for producing an electrophotographic photosensitive member according to the present embodiment includes a cleaning step of cleaning the impact-pressed conductive substrate to which metal soap is attached by the method for cleaning the substrate according to the present embodiment. Is not particularly limited as long as it is a manufacturing method in which

The method for producing the electrophotographic photosensitive member according to the present embodiment includes, for example, a cleaning step of cleaning the impact-pressed conductive substrate to which metal soap is attached by the substrate cleaning method according to the present embodiment, and the conductive substrate. It is preferable to include a photosensitive layer forming step of forming a photosensitive layer on the surface.

When an electrophotographic photosensitive member is manufactured using an impact-pressed substrate with metal soap attached, a coating liquid for forming a photosensitive layer or the like is applied onto the surface of the substrate to form a coating liquid. Coating film defects such as uneven coating and repelling may occur, and the accuracy of forming the photosensitive layer may be lowered.
On the other hand, the method for producing an electrophotographic photosensitive member according to the present embodiment includes a step of cleaning the conductive substrate by the method for cleaning the substrate according to the present embodiment. Therefore, it is considered that the occurrence of coating film defects when the coating liquid for forming a photosensitive layer or the like is applied on the surface of the substrate to form the layer is suppressed.

The photosensitive layer formed in the photosensitive layer forming step may be a single-layer type photosensitive layer in which a charge generating material and a charge transporting material are contained in the same photosensitive layer to integrate functions, and the charge generating layer and the charge transporting layer may be used. A laminated photosensitive layer in which the functions having and are separated may be used. When the photosensitive layer is a laminated photosensitive layer, the order of the charge generating layer and the charge transporting layer is not particularly limited, but the electrophotographic photosensitive member has a charge generating layer, a charge transporting layer, and surface protection on a conductive substrate. A structure having layers in this order is preferable. Further, the electrophotographic photosensitive member may include a layer other than these layers.
FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of the electrophotographic photosensitive member manufactured by the manufacturing method according to the present embodiment. The electrophotographic photosensitive member 107A has a structure in which an undercoat layer 101 is provided on a conductive substrate 104, and a charge generation layer 102, a charge transport layer 103, and a surface protection layer 106 are sequentially formed on the undercoat layer 101. In the electrophotographic photosensitive member 107A, a photosensitive layer 105 whose functions are separated into a charge generating layer 102 and a charge transporting layer 103 is configured.

Further, FIG. 2 is a schematic cross-sectional view showing another example of the layer structure of the electrophotographic photosensitive member manufactured by the manufacturing method according to the present embodiment. The electrophotographic photosensitive member 107B shown in FIG. 2 has a structure in which an undercoat layer 101 is provided on a conductive substrate 104, and a photosensitive layer 105 and a surface protective layer 106 are sequentially formed. In the electrophotographic photosensitive member 107B, a single-layer type photosensitive layer is formed in which a charge generating material and a charge transporting material are contained in the same photosensitive layer 105 and the functions are integrated.

The electrophotographic photosensitive member in the present embodiment may or may not be provided with the undercoat layer 101 and the surface protective layer 106 as long as the substrate and the photosensitive layer are provided.

Hereinafter, a method for producing each layer of the electrophotographic photosensitive member according to the present embodiment will be described in detail. The reference numerals will be omitted.

(Undercoat layer forming process)
The undercoat layer forming step is, for example, a step of forming a layer containing inorganic particles and a binder resin.

The formation of the undercoat layer is not particularly limited, and a well-known forming method is used. For example, a coating for forming the undercoat layer in which components constituting the undercoat layer such as inorganic particles and a binder resin are added to a solvent. This is done by forming a liquid coating film, drying the coating film, and heating if necessary.

As the solvent for preparing the coating liquid for forming the undercoat layer, known organic solvents such as alcohol-based solvent, aromatic hydrocarbon solvent, halogenated hydrocarbon solvent, ketone-based solvent, ketone alcohol-based solvent, and ether-based solvent are used. Examples thereof include solvents and ester-based solvents.
Specific examples of these solvents include methanol, ethanol, n-propanol, iso-propanol, n-butanol, benzyl alcohol, methyl cellsolve, ethyl cell solution, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, and the like. Examples thereof include ordinary organic solvents such as n-butyl acetate, dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene and toluene.

Examples of the method for dispersing the inorganic particles when preparing the coating liquid for forming the undercoat layer include known methods such as a roll mill, a ball mill, a vibrating ball mill, an attritor, a sand mill, a colloid mill, and a paint shaker.

Examples of the method of applying the coating liquid for forming the undercoat layer onto the conductive substrate include a blade coating method, a wire bar coating method, a spray coating method, a dip coating method, a bead coating method, an air knife coating method, and a curtain coating method. Ordinary methods such as.

The film thickness of the undercoat layer is set, for example, preferably in the range of 15 μm or more, more preferably 20 μm or more and 50 μm or less.

(Intermediate layer forming process)
The electrophotographic photosensitive member may further provide an intermediate layer between the undercoat layer and the photosensitive layer. The intermediate layer forming step is a step of forming a layer containing components constituting the intermediate layer such as a binder resin.

The formation of the intermediate layer is not particularly limited, and a well-known forming method is used. For example, a coating film of an intermediate layer forming coating film in which the components constituting the intermediate layer are added to a solvent is formed to form the coating film. Is dried and heated as needed.
As a coating method for forming the intermediate layer, ordinary methods such as a dip coating method, a push-up coating method, a wire bar coating method, a spray coating method, a blade coating method, a knife coating method, and a curtain coating method are used.

The film thickness of the intermediate layer is preferably set in the range of 0.1 μm or more and 3 μm or less. The intermediate layer may be used as the undercoat layer.

(Charge generation layer forming process)
The charge generation layer forming step is, for example, a step of forming a layer containing a charge generating material and a binder resin. The charge generation layer forming step may be a step of depositing a charge generating material to form a vapor deposition layer. The vapor-deposited layer of the charge generating material is suitable when a non-interfering light source such as an LED (Light Emitting Diode) or an organic EL (Electro-Lumisensence) image array is used.

The formation of the charge generation layer is not particularly limited, and a well-known formation method is used. For example, a coating film of a coating liquid for forming a charge generation layer is formed by adding a component constituting the charge generation layer to a solvent. This is done by drying the coating film and heating it if necessary. The charge generation layer may be formed by vapor deposition of a charge generation material. The formation of the charge generation layer by thin film deposition is particularly suitable when a condensed ring aromatic pigment or a perylene pigment is used as the charge generation material.

Solvents for preparing the coating liquid for forming the charge generation layer include methanol, ethanol, n-propanol, n-butanol, benzyl alcohol, methyl cellsolve, ethyl cell solution, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, n acetate. -Butyl, dioxane, tetrahydrofuran, methylene chloride, chloroform, chlorobenzene, toluene and the like can be mentioned. These solvents may be used alone or in admixture of two or more.

As a method of dispersing particles (for example, a charge generating material) in a coating liquid for forming a charge generating layer, for example, a media disperser such as a ball mill, a vibrating ball mill, an attritor, a sand mill, a horizontal sand mill, a stirrer, or an ultrasonic disperser. , Roll mills, high pressure homogenizers and other medialess dispersers are used. Examples of the high-pressure homogenizer include a collision method in which a dispersion liquid is dispersed by a liquid-liquid collision or a liquid-wall collision in a high-pressure state, and a penetration method in which a dispersion liquid is dispersed by penetrating a fine flow path in a high-pressure state.
At the time of this dispersion, it is effective to set the average particle size of the charge generating material in the coating liquid for forming the charge generating layer to 0.5 μm or less, preferably 0.3 μm or less, and more preferably 0.15 μm or less. ..

As a method of applying the coating liquid for forming the charge generation layer on the undercoat layer (or on the intermediate layer), for example, a blade coating method, a wire bar coating method, a spray coating method, a dipping coating method, a bead coating method, and an air knife coating method. Examples thereof include ordinary methods such as a method and a curtain coating method.

(Charge transport layer forming process)
The charge transport layer forming step is, for example, a step of forming a layer containing the charge transport material and the binder resin. The charge transport layer may be a layer containing a polymer charge transport material.

The formation of the charge transport layer is not particularly limited, and a well-known formation method is used. For example, a coating film of a coating liquid for forming a charge transport layer is formed by adding a component constituting the charge transport layer to a solvent. This is done by drying the coating film and heating it if necessary.

Solvents for preparing the coating liquid for forming the charge transport layer include aromatic hydrocarbons such as benzene, toluene, xylene and chlorobenzene; ketones such as acetone and 2-butanone; methylene chloride, chloroform, ethylene chloride and the like. Halogenated aliphatic hydrocarbons; ordinary organic solvents such as cyclic or linear ethers such as tetrahydrofuran and ethyl ether can be mentioned. These solvents are used alone or in combination of two or more.

When the coating liquid for forming the charge transport layer is applied onto the charge generating layer, the coating methods include blade coating method, wire bar coating method, spray coating method, immersion coating method, bead coating method, air knife coating method, and curtain. Examples thereof include a usual method such as a coating method.

(Protective layer forming process)
The protective layer is provided on the photosensitive layer as needed. The protective layer is provided, for example, for the purpose of preventing a chemical change of the photosensitive layer during charging and further improving the mechanical strength of the photosensitive layer.

The protective layer forming step is, for example, a step of forming a layer containing components constituting the protective layer such as a binder resin. The formation of the protective layer is not particularly limited, and a well-known forming method is used. For example, a coating film of a coating liquid for forming a protective layer is formed by adding a component constituting the protective layer to a solvent, and the coating film is formed. Is dried, and if necessary, it is cured by heating or the like.

As the solvent for preparing the coating liquid for forming the protective layer, aromatic solvents such as toluene and xylene; ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ester solvents such as ethyl acetate and butyl acetate; tetrahydrofuran , Ether-based solvent such as dioxane; cellosolve-based solvent such as ethylene glycol monomethyl ether; alcohol-based solvent such as isopropyl alcohol and butanol. These solvents are used alone or in combination of two or more.
The coating liquid for forming the protective layer may be a solvent-free coating liquid.

As a method of applying the coating liquid for forming a protective layer on a photosensitive layer (for example, a charge transport layer), a dip coating method, a push-up coating method, a wire bar coating method, a spray coating method, a blade coating method, a knife coating method, and a curtain coating method are used. Ordinary methods such as law can be mentioned.

(Single-layer photosensitive layer forming process)
The single-layer photosensitive layer (charge generation / charge transport layer) forming step forms a layer containing, for example, a charge generation material, a charge transport material, and, if necessary, a binder resin and other well-known additives. It is a process to do.
The method for forming the single-layer photosensitive layer is the same as the method for forming the charge generation layer and the charge transport layer.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to the following Examples. The materials, amounts used, ratios, treatment procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present embodiment. Unless otherwise specified, "part" means "part by mass".

[Example 1]
(Preparation of impact-pressed substrate with metal soap attached)
-Slag preparation step, lubricant application step A slag of JIS designation 1050 alloy with aluminum purity of 99.5% by mass or more was prepared.
100 parts of zinc stearate was applied to the slag by immersion coating to form a lubricant coating film on the slag surface.

-Impact press processing and ironing process Using the slag on which the lubricant coating film is formed, a cylindrical substrate with a bottom surface is produced by impact pressing with a die (female type) and a punch (male type). It was designated as "impact-pressed substrate with metal soap attached".

(First cleaning process)
The organic cleaning agents shown in Table 1 were placed in a cleaning tank 1 having an ultrasonic transmitting ability, and the temperature was kept at 80 ° C. Next, the substrate prepared above was immersed in the organic cleaning agent in the cleaning tank 1 and brought under reduced pressure (-88 kPa). Then, the substrate was washed by ultrasonic immersion for 4 minutes while applying ultrasonic waves to the substrate under a reduced pressure of 80 ° C.

(Drying step 1)
The substrate washed by the first washing step was dried under reduced pressure (-8 kPa) at 80 ° C. in a dryer to remove the organic cleaning agent adhering to the surface of the substrate.

(Second cleaning process)
The water-based cleaning agent (alkaline aqueous solution) shown in Table 1 was placed in the cleaning tank 2 and kept warm at 25 ° C. Next, the substrate that had undergone the drying step was immersed in the water-based cleaning agent in the cleaning tank 2 and simply immersed at 40 ° C. for 4 minutes to wash the substrate.

(Drying step 2)
The substrate that had undergone the second cleaning step was immersed in a cleaning tank 3 containing pure water at 60 ° C., simply immersed for 4 minutes, and then the substrate was pulled up to dry the substrate.

[Examples 2 to 16 and Comparative Examples 1 to 3]
The impact-pressed substrate to which the metal soap was attached was washed by the same operation as in Example 1 except that the materials and conditions in the first step and the second step were set to the specifications shown in Table 1.

[Evaluation of corrosion of the substrate]
The outer peripheral surface of the substrate in each example was magnified to 1 cm × 1 cm by a microscope, and the surface was observed, and the presence or absence of corrosion on the observed surface was evaluated according to the following criteria.
G1: 1cm ² No corrosion on the observation surface.
G2: 1cm ² Corrosion occurs in 1 to 3 places on the observation surface.

[Evaluation of substrate detergency]
A mixed solution of ink and water was dropped onto the outer peripheral surface of the cylindrical substrate in each example. The way the mixed solution was repelled at this time was visually observed on the surface, and the detergency of the substrate was evaluated according to the following criteria.
G1: There is no repelling.
G2: Small punctate repellents are observed in 1 to 3 places, but this is acceptable.
G3: Small punctate cissing is observed, but acceptable.
G4: There is a repellent.

From the above results, it was found that the method for cleaning the substrate in the examples sufficiently cleans the metal soap adhering to the substrate while suppressing the corrosion of the substrate, as compared with the method for cleaning the substrate in the comparative example.

101 Undercoat layer 102 Charge generation layer 103 Charge transport layer 104 Conductive substrate 105 Photosensitive layer 106 Surface protective layer 107A, 107B Electrophotographic photosensitive member

Claims (10)

The first cleaning step of cleaning the impact-pressed substrate to which the metal soap is attached with an organic cleaning agent containing at least 10% by mass or more of at least one selected from glycol ether and an aliphatic alcohol.
A second cleaning step of cleaning the substrate after the first cleaning step with an acidic or alkaline aqueous cleaning agent, and
A method for cleaning a substrate, including. The first cleaning step of cleaning the impact-pressed substrate to which the metal soap is attached with an organic cleaning agent until the amount of the metal soap attached is 30 × 10 ^-3 mg / cm ² or less.
A second cleaning step of cleaning the substrate after the first cleaning step with an acidic or alkaline aqueous cleaning agent, and
A method for cleaning a substrate, including. The method for cleaning a substrate according to claim 1 or 2, wherein the second cleaning step is a step of cleaning the substrate with an alkaline aqueous cleaning agent. The method for cleaning a substrate according to claim 3, wherein the pH of the alkaline aqueous cleaning agent at 25 ° C. is 9 or more and 12 or less. The method for cleaning a substrate according to any one of claims 1 to 4, wherein the liquid temperature of the organic cleaning agent is 60 ° C. or higher. The method for cleaning a substrate according to claim 5, wherein the liquid temperature of the organic cleaning agent is 80 ° C. or higher. The method for cleaning a substrate according to any one of claims 1 to 6, wherein the first cleaning step is performed under reduced pressure. The method for cleaning a substrate according to any one of claims 1 to 7, wherein the metal soap contains a metal stearic acid salt. The method for cleaning a substrate according to any one of claims 1 to 8, wherein the substrate is a cylindrical substrate. A cleaning step of cleaning the impact-pressed conductive substrate to which metal soap is attached by the substrate cleaning method according to any one of claims 1 to 9.
A photosensitive layer forming step of forming a photosensitive layer on the conductive substrate, and
A method for producing an electrophotographic photosensitive member, including.