JPH0968821A - Electrophotographic organic photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an undercoat layer having satisfactory adhesion to an electrically conductive substrate and a photosensitive layer and giving a satisfactory image due to high chargeability and low potential in a light part in an environment at 5-35 deg.C and 20-85% RH and having stable chargeability and low potential in a light part even after a repetition test. SOLUTION: In this electrophotographic org. photoreceptor consisting of an electrically conductive substrate, an undercoat layer and a photosensitive layer, the undercoat layer is made of N-(alkoxymethyl)nylon as copolymerized nylon based on 12-nylon or a mixture of nylon with alcohol-soluble copolymerized nylon. The rate of N-alkoxymethylation is 1 to <15% for nylon as a whole and the thickness of the undercoat layer is <=1.5μm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic organic photoconductor, and more particularly to a technique for improving an undercoat layer of the photoconductor.

[0002]

2. Description of the Related Art Organic photoconductors are currently mainly used as photoconductors for laser beam printers and copying machines. The Carlson method is mainly applied to image formation using these photoconductors. Image formation by this method is performed by charging by corona discharge to the photoconductor in a dark place, formation of an electrostatic latent image by exposing the charged surface of the photoconductor, development of the electrostatic latent image by toner, and development. The toner image thus formed is fixed on paper or the like. After that, the photoconductor is reused after removing the charge, removing the residual toner, and removing the charge. The main characteristics required for these photoconductors are stability of charging due to corona discharge in the dark, fast light emission with a small amount of light (that is, high sensitivity and fast photoresponse). Is required. It is generally known to provide an undercoat layer between the support and the photosensitive layer as a means for improving the stability of charging by corona discharge in the dark.

Further, it has been proposed that the photosensitive layer has a laminated structure in which a charge generation layer and a charge transport layer are functionally separated.
In general, the charge generation layer is an extremely thin layer having a thickness of 0.2 to 1.5 μm. Therefore, defects on the surface of the support, such as unevenness and deposits, make the thickness of the charge generation layer uneven, resulting in image defects. However, there is a drawback that an image defect may occur due to a local deterioration of the charge injection preventing function under environmental conditions of high temperature and high humidity.

For this reason, an undercoat layer having a function of covering surface defects of the support, a function of preventing charge injection, and a function as an adhesive layer is provided between the charge generation layer and the support. Is proposed. So far, polyamide (JP-A-46-47344, JP-A-52-25638), polypebutide (JP-A-53-48523), casein (JP-A-55) are provided between the photosensitive layer and the support. -103556), polyvinyl alcohol (JP-A-52-100240), ethyl cellulose
(Japanese Patent Application Laid-Open No. 55-143564), a material in which polyamide or the like is mixed with conductive particles (Japanese Patent Application Laid-Open No. 2-74949).
It is known to use an undercoat layer made of N-alkoxymethylated nylon resin of nylon 12, preferably nylon resin in which alumina-coated titanium oxide fine particles are dispersed (Japanese Patent Laid-Open No. 5-72787). ing.

[0005]

However, when an undercoat layer made of these materials is applied to a photoreceptor,
At present, the characteristics required for the photoconductor are not sufficiently satisfied. Specifically, when an undercoat layer made of polyamide is applied to a photoconductor, at a film thickness of 0.3 μm or more, the initial bright part potential (VL) is high, and at the same time, the bright part potential is increased by repeated tests. There is a drawback that an increase in (VL) is recognized.

With a film thickness of 0.3 μm or less, even when an aluminum drum, which has been subjected to mirror finishing or other finishing using a diamond bite, is used as the conductive substrate, surface defects (roughness, unevenness) of the conductive substrate are caused. It was not possible to prevent image defects due to adhered substances) or insufficient ability of the function of preventing charge injection. As a method for preventing the bright portion potential (VL) from rising when the thickness of the undercoat layer is 0.3 μm or more, it has been proposed to use a mixture of conductive particles and a polymer such as polyamide. Although it is possible to prevent the partial potential (VL) from rising, on the contrary, there is a drawback that the charge injection preventing function is deteriorated and the initial charging ability (VO) is decreased. Therefore, a polyamide layer having a charge injection preventing function is used together. It is the current situation. In addition, in the case of water-soluble polymers such as polypeptides, casein and polyvinyl alcohol, 3
When left in a high temperature and high humidity condition such as 5 ° C. and 95% RH, there are drawbacks such as occurrence of image defects and poor adhesion.

The above-mentioned Japanese Patent Laid-Open No. 5-72787 describes that a highly sensitive photoreceptor can be obtained by using N-alkoxymethylated nylon 12 as an undercoat layer (undercoat layer). However, it has a drawback that the residual charge is remarkably increased by the repeated test.

Therefore, an object of the present invention is to provide an organic photoconductor for electrophotography which satisfies the following items 1) to 3). 1) To provide a good image based on high chargeability and low light portion potential in an environment of 5 to 35 ° C. and 20 to 85% RH. 2) Stable chargeability and low light area potential even after repeated tests. 3) To provide an undercoat layer having good adhesion to a conductive substrate and a photosensitive layer.

[0009]

In order to solve the above-mentioned problems, the present invention has the following constitution. (1) In an organic electrophotographic photoreceptor for electrophotography comprising a conductive substrate, an undercoat layer and a photosensitive layer, the undercoat layer is N of copolymerized nylon containing nylon 12 as a main component.
-(Alkoxymethyl) nylon alone or a mixture of the nylon and an alcohol-soluble copolymerized nylon, the N-alkoxymethylation rate of the entire nylon is 1% or more and less than 15%, and the undercoat layer is Is a film thickness of 1.5 μm or less.

(2) The undercoat layer in the organic photoconductor for electrophotography according to (1) above is produced by the reaction of titanium tetrachloride with hydrogen and oxygen and has an anatase content of 50.
˜90%, the rest having a rutile type crystal structure, and a titanium dioxide having a particle size of 70 nm or less made of nylon 100
An organic photoconductor for electrophotography, characterized in that 10 to 300 parts by weight are dispersed and the thickness of the undercoat layer is 7 μm or less.

(3) In an organic photoconductor for electrophotography comprising a conductive substrate, an undercoat layer and a photosensitive layer, the undercoat layer has the following formula (1) containing nylon 12 as a main component: (X ¹ in the formula (1) is expressed by the following formulas (2) to (4), (In the formulas (2) to (4), m and n are integers of 2 to 20, q is an integer of 0 to 20, R ¹ , R ² and R ⁵ are alkylene groups and R is an integer.
³ , R ⁴ represents an alkyl group), a modified copolymerized nylon having a structure represented by the formula (1) selected from the group consisting of substituents represented by (1) or the nylon and an alcohol-soluble copolymerized nylon. An organic photoreceptor for electrophotography, characterized in that the N-methyl modification ratio of the nylon as a whole is 1% or more and less than 20%, and the film thickness of the nylon layer is 1.5 μm or less. is there. In addition, R ¹ , R ² ,
The carbon number of the alkylene group of R ^{5 and} the alkyl group of R ³ and R ⁴ is preferably within the range of 1 to 5.

(4) The undercoat layer in the organic photoconductor for electrophotography according to (3) above is produced by the reaction of titanium tetrachloride with hydrogen and oxygen, and has an anatase content of 50.
˜90%, the rest having a rutile type crystal structure, and a titanium dioxide having a particle size of 70 nm or less made of nylon 100
An organic photoconductor for electrophotography, characterized in that 10 to 300 parts by weight are dispersed and the thickness of the undercoat layer is 7 μm or less.

(5) In the organic photoconductor for electrophotography according to the above (1) to (4), the photosensitive layer is a laminated type having a charge generation layer and a charge transport layer, and the charge generation agent in the charge generation layer is A phthalocyanine-based organic pigment, wherein the charge transporting material in the charge transporting layer is represented by the following formula: (In the formula, R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are a hydrogen atom, a halogen atom, an alkoxy group or an optionally substituted alkyl group or an aryl group, and R ¹³ is a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group. The group represents a group) and an organic photoconductor for electrophotography containing a distyryl compound.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Examples of alcohol-soluble nylon that can be used in the present invention include 6/66/12 nylon (trade name: Daiamide T171, manufactured by Daicel Hurtz Ltd.), 6/66/610 nylon ( Product name: Amilan CM8000, manufactured by Toray Industries, Inc., 6/66/12 nylon (Product name: Platabond H005, manufactured by Nippon Rilsan Co., Ltd.), and other alcohol-soluble nylons.
Trade name PlataBond NX1178 (manufactured by Nippon Rilsan Co., Ltd.), trade name PlataBond NX1602 (manufactured by Nippon Rilsan Co., Ltd.), trade name PlataBond NX127
6TC (manufactured by Nippon Rilsan Co., Ltd.) and the like.

Further, copolymerized nylon N- (alkoxymethyl) nylon containing Nylon 12 as a main component which can be used in the present invention (hereinafter referred to as "Nylon 12 base N-
Examples of (alkoxymethyl) -modified nylon ”include N- (methoxymethyl) nylon 12 (trade name: Toresin G550, manufactured by Teikoku Chemical Industry Co., Ltd.), N- (methoxymethyl) nylon 12 (trade name: phi). Resin FR
301, manufactured by Lead City Co., Ltd., and the like.

In the present invention, ethoxy-modified products, butoxy-modified products, Si-containing alcohol-modified products, and Si-containing alkoxide-modified products of N- (methoxymethyl) nylon 12 are also used. These modified products are obtained, for example, by mixing Nylon 12 base N- (methoxymethyl) modified nylon (trade name: Fine Resin FR301) and trimethylsilanol, and reacting at a temperature of 80 ° C. or higher.

Further, in the present invention, the undercoat layer using the nylon is produced by the reaction of titanium tetrachloride with hydrogen and oxygen, and the content of the anatase type is 50-9.
When the content of titanium dioxide is 0% and the rest has a rutile type crystal structure and the particle size is 70 nm or less and 10 to 300 parts are dispersed in 100 parts by weight of nylon, the thickness of the undercoat layer is 7 μm. In the following, preferably in the range of 1 to 5 μm, extremely stable chargeability and a low bright portion potential are exhibited even after repeated tests.

Titanium dioxide which can be used in the present invention is, for example, Titanium Dioxide P2 under the trade name.
5 (manufactured by Nippon Aerosil Co., Ltd.) and the like.

When the photosensitive layer is a laminated type having a charge generating layer and a charge transporting layer, in order to obtain highly sensitive and stable repeating characteristics, selection of the charge generating agent in the charge generating layer and charge transporting are performed. The choice of charge transport material in the layer is also important. Phthalocyanine pigments and bisazo pigments having a specific structure are particularly effective as the charge generating agent. Specific examples of the phthalocyanine pigment that can be used in the present invention are shown in Tables 1 and 2 below.

[0020]

[Table 1]

[0021]

[Table 2]

Specific examples of the distyryl type charge transport material used in the present invention are shown in Tables 3 to 7.

[0023]

[Table 3]

[0024]

[Table 4]

[0025]

[Table 5]

[0026]

[Table 6]

[0027]

[Table 7]

In the present invention, when the photosensitive layer is a laminated type having a charge generating layer and a charge transporting layer, these distyryl type charge transporting substances are essential components, and also hydrazone type, stilbene type and amine type. A diamine-based charge transport material can be used.

The organic photoreceptor for electrophotography according to the invention (1) has a nylon 12 base N as an undercoat layer.
-(Alkoxymethyl) -modified nylon alone or a mixture of the nylon and an alcohol-soluble copolymerized nylon, and the N-alkoxymethylation ratio of the entire nylon is less than 15%, preferably 10% or less. By using, it becomes possible to have a low bright portion potential and good repeated test characteristics. The details of this reason are unknown, but it is presumed that the reason is as follows. The N-methoxymethylation rate of commercially available N- (methoxymethyl) nylon that is usually used is 18% or more. The N-methoxymethylated portion of nylon is an active site that is highly reactive and can easily undergo a substitution reaction with another alcohol system, and it is presumed that this portion acts as a charge trap. When the charge is accumulated in the charge trap portion in the undercoat layer, it is presumed that the negative potential is correspondingly induced on the surface portion of the photoconductor and the residual potential is increased. Therefore, it is estimated that the higher the N-alkoxymethylation rate of N- (alkoxymethyl) nylon used for the undercoat layer and the thicker the film, the higher the residual potential in the repeated test. This estimation was supported by the examples described below.

Further, the higher the N-alkoxymethylation rate, the lower the Tg, the higher the water absorption rate, and the lower the electric resistance under high temperature and high humidity, which causes a problem that image defects increase.

On the other hand, the reason why the adhesion between the conductive substrate and the undercoat layer with respect to the photosensitive layer becomes good is presumed to be due to the material properties of N- (alkoxymethyl) nylon, mainly the low elastic modulus. -Alkoxymethylation rate is 1
% Or more, preferably 3% or more, good adhesion is exhibited,
The higher the N-alkoxymethylation rate, the better the adhesion.

However, even when the above-mentioned nylon is used, when the film thickness becomes thicker than 1.5 μm and 2 μm or more, the residual charge is remarkably increased by the repeated test. This increase in residual charge is produced by the reaction of titanium tetrachloride with hydrogen and oxygen, the content of the anatase type is 50 to 90%, the rest has a rutile type crystal structure, and the particle size is 70 nm or less. It can be prevented by the action of titanium dioxide.
Although the details of the cause are unknown, it is presumed that, as a result of the peculiar mixed crystal structure and peculiar manufacturing method, charge transfer easily occurs without lowering the resistance of UCL.

If necessary, the surface of the titanium dioxide is treated with a silicone-based surface treatment agent such as aminosilane, whereby the dispersibility of titanium dioxide in nylon is improved and, as a result, the stability of the charging potential is improved.

Further, by substituting the alkoxy group of N- (alkoxymethyl) nylon of the copolymerized nylon containing Nylon 12 as the main component with a silicone alcohol, the water absorption rate of the silicone is reduced by the water repellency of the silicone. Image defects at high temperature and high humidity can be prevented.

That is, the undercoat layer is nylon 1
In the case of the N-methyl modified nylon of the copolymerized nylon represented by the formula (1) containing 2 as the main component alone or in the case of the mixture of the nylon and the alcohol-soluble nylon, N-methyl as the whole nylon is used. A nylon having a modification rate of 1% or more, preferably 3% or more and less than 20%, preferably 15% or less, and the undercoat layer having a thickness of 1.
By forming the film having a thickness of 5 μm or less, preferably 1.0 μm or less, more preferably 0.5 μm or less, image defects can be prevented especially under high temperature and high humidity. That is, when the alkoxy group of N- (alkoxymethyl) nylon is replaced with a silicone-based alcohol, the water absorption rate is small due to the water repellency of silicone, so the upper limit of the N-methyl modification rate should be increased accordingly. You can Here, the N-methyl modification rate is the following formula, The number of repeating units a and b in the nylon structure represented by the formula (X ¹ in the formula is selected from the group consisting of the substituents of the formulas (2) to (4)) is represented as follows. N-methyl modification rate = b / (a + b)

In addition to the UCL, not only the UCL but also the combination of the charge generation layer and the charge transport layer is important in order to realize low residual potential and high repeated stability with low residual potential. Although details of the cause are unknown, it is achieved by a combination of a phthalocyanine pigment and a distil charge transport having a specific structure.

In the present invention, the photosensitive layer has a laminated structure as shown in FIG. 1, that is, it is composed of a conductive substrate 1, an undercoat layer 2, a charge generation layer 3 and a charge transport layer 4. When it is applied to a charge-type laminated type photoreceptor, particularly remarkable effects are obtained.

A positive charging type laminated photoreceptor comprising the conductive substrate 11, the undercoat layer 12, the charge transport layer 13, the charge generation layer 14 and the overcoat layer 15 shown in FIG. 2 and the conductivity shown in FIG. Base 21, undercoat layer 2
2. The positively chargeable single-layer type photosensitive member composed of the photosensitive layer 23 composed of the charge generating material, the charge transporting material, and the resin binder has a thin charge generating layer in the vicinity of the conductive substrate. Image defects due to surface defects of the conductive substrate are unlikely to occur, but when the present invention is applied, it is possible to provide a photoreceptor having a low initial bright portion potential and having no image defects in repeated tests.

Examples of the conductive substrate that can be used in the present invention include aluminum cylinders and aluminum vapor deposited films. The charge generating layer is composed of a charge generating agent and a resin binder.

The charge generating agents are listed in Tables 2 and 3 above.
Various phthalocyanine compounds and azo compounds shown in can be used. Further, as the binder for the charge generation layer, polycarbonate, polyester, polyamide, polyurethane, epoxy, polyvinyl butyral, polyvinyl acetal, phenoxy resin, silicone resin, acrylic resin, vinyl chloride resin, vinylidene chloride resin, vinyl acetate resin, homar resin , Cellulose resins, or copolymers thereof, and halides or cyanoethylated compounds thereof are used, and modified vinyl chloride resins, polyvinyl acetal resins, and polyvinyl butyral resins are particularly preferable.

The charge transport layer comprises a charge transport material and a resin binder. As the charge transport material, diamine compounds, hydrazone compounds, and stilbene compounds can be used in addition to the distil compounds shown in Tables 4 to 7 as essential components. As the resin binder for the charge transport layer, polycarbonate, polystyrene, polyphenyl ether, acrylic resin or the like can be used,
Polycarbonate is particularly preferable.

[0042]

Embodiments of the present invention will be described below. In the following examples, a case where the invention is applied to a negative charging type laminated type photoreceptor will be described. Examples 1 to 4 and Comparative Examples 1 to 11 [Preparation of Conductive Substrate] Aluminum made by extrusion processing and having grooves for interference prevention machined on the surface is machined to have a thickness of 1.0 mm, a length of 350 mm, and an outer diameter. After ultrasonically cleaning a 60 mm drum with trichlene or the like, the surface of the drum was rubbed with a sponge while dripping an alkaline cleaning solution containing a surfactant, and then ultrasonically cleaned with warm pure water at 80 ° C. and dried.

[Preparation of Coating Solution for Undercoat Layer] A commercially available alcohol-soluble nylon, a nylon 12 base copolymer having a trade name of Daiamide T171 (manufactured by Daicel Schultz) and N- (methoxymethyl) nylon 12 ( 100 parts by weight of a mixture of trade name Fine Resin FR301 and Lead City Co., Ltd. is dissolved in a mixed solvent of 500 parts by weight of methanol and 500 parts by weight of dichloromethane to prepare coating solutions A-1 to 5 for undercoating. did. The mixing ratios and N-methoxymethylation ratios of the above nylons in the prepared undercoat coating liquids A-1 to A-5 are shown in Table 8 below.
Shown in

[0044]

[Table 8]

[Preparation of Coating Liquid for Charge Generation Layer] The compounds shown in Table 1 (Compound No. CG-P1,
5 parts by weight of metal-free phthalocyanine) and 5 parts by weight of modified vinyl chloride (trade name MR110, manufactured by Zeon) as a binder are mixed with 500 parts by weight of dichloromethane and kneaded with a mixer for 3 hours to prepare a charge generation layer. Was prepared.

[Preparation of Coating Solution for Charge Transport Layer] As the charge transport material, the following formula, A hydrazone compound represented by (Compound No. CT-28)
8 parts by weight and 2 parts by weight of a distil-based diamine compound (Compound No. CT-1) shown in Table 3, a polycarbonate as a resin binder (trade name Panelite L122
5: Teijin Chemicals Ltd. 10 parts by weight, 2,6 di-t-butylhydroxytoluene 0.4 parts by weight as an antioxidant, dichloromethane 80 parts by weight, silicone oil KP-3400.06 parts by weight To prepare a coating solution for the charge transport layer.

[Production of Photoreceptor] On the above-mentioned aluminum substrate, an undercoat layer having a film thickness of 0.5 μm, 1 μm, or 2 μm was applied by a dip method using the coating solutions A-1 to 5 for the undercoat layer. And dried. Further, a charge generation layer (0.3 μm) and a charge transport layer (20 μm) are provided on the undercoat layer by using the above-mentioned charge generation layer coating liquid and charge transport layer coating liquid, and the photoconductor [A1-1 ]-[A5-3] were produced.

Examples 5 to 8 and Comparative Examples 12 to 22 [Preparation of coating liquid for undercoat layer] Commercially available alcohol-soluble nylon, trade name Daiamide T171 (manufactured by Daicel Schultz), nylon 12 base co-weighing. Based on the combination, the N-methoxymethylation rate was 1 by a known method.
%, 10%, 15%, 20%, and different nylons were produced. 100 parts by weight of these nylons are mixed with 50 parts of methanol.
It was dissolved in a mixed solvent of 0 parts by weight and 500 parts by weight of dichloromethane to prepare coating solutions B-1 to 5 for the undercoat layer. The N-methoxymethylation rate of the coating liquid is as follows. B-1 (1%), B-2 (5%), B-3 (10
%), B-1 (15%), B-1 (20%).

[Preparation of Photoreceptor] After washing the aluminum substrate in the same manner as in Example 1, the coating solution B-1 for the undercoat layer was prepared.
5 to 5, undercoat layers having film thicknesses of 0.5 μm, 1 μm and 2 μm were applied by a dip method and dried. Further, a charge generation layer (0.3 μm) and a charge transport layer (20 μm) are provided on the undercoat layer by the above-mentioned coating liquid for the charge generation layer and coating liquid for the charge transport layer,
Photoconductors [B1-1] to [B5-3] were produced.

Examples 9 to 16 and Comparative Examples 23 to 26 [Preparation of coating liquid for undercoat layer] N- (methoxymethyl) nylon 12 (trade name Fine Resin FR30)
1, manufactured by Lead City Co., Ltd., and subjected to alcohol substitution reaction in various alcohol solutions to produce various modified nylons. The produced nylon has the following formula containing nylon 12 as a main component, X ¹ in the structural formula represented by is shown in Table 9 below.

[0051]

[Table 9]

50 parts by weight of the modified nylon and 50 nylon 12 base copolymer of alcohol-soluble nylon (trade name: Daiamide T171 (manufactured by Daicel Schultz)).
500 parts by weight of methanol and 5 parts by weight of dichloromethane
It was dissolved in a mixed solvent of 00 parts by weight to prepare coating solutions C-1 to C-4 for the undercoat layer.

[Production of Photoreceptor] After washing the aluminum substrate in the same manner as in Example 1, the coating solution C-1 for the undercoat layer was prepared.
4 to 4, undercoat layers having a film thickness of 0.5 μm, 1 μm and 2 μm were applied by a dip method and dried. Further, a charge generation layer (0.3 μm) and a charge transport layer (20 μm) are provided on the undercoat layer by the above-mentioned coating liquid for the charge generation layer and coating liquid for the charge transport layer,
Photoconductors [C1-1] to [C4-3] were produced.

Examples 17 to 22 and Comparative Examples 27 to 32 [Preparation of coating liquid for undercoat layer] Commercially available alcohol-soluble nylon with a trade name of Daiamide T171 (manufactured by Taisel Schultz) and a nylon 12 base. Polymer 7
0 parts by weight and 30 parts by weight of N- (methoxymethyl) nylon 12 (trade name: Fine Resin FR301, manufactured by Lead City Co., Ltd.) were added to 400 parts by weight of methanol and 500 parts of dichloromethane.
It was dissolved in a mixed solvent of parts by weight to prepare a coating liquid D for undercoat. Separately, it was produced by the reaction of titanium tetrachloride surface-treated with aminosilane, hydrogen and oxygen in 1200 parts by weight of methanol, the content of anatase type was 70%, and the rest had a rutile type crystal structure and a particle size thereof. Is 20
nm titanium dioxide (trade name: titanium dioxide P25) (hereinafter referred to as "ASP25") 1000 parts by weight and 10φ zirconia ball 200 as a dispersion medium.
0 parts by weight was subjected to ball mill dispersion treatment for 7 days or more to prepare paste A. The coating liquid D and the paste A were mixed and dispersed for 2 hours with a paint shaker to prepare coating liquids D-1 to D-4 for the undercoat layer. Table 1 shows the composition ratio of nylon and titanium dioxide (TiO ₂ ) in the prepared coating liquid.
3 is shown.

[Preparation of Photoreceptor] After the aluminum substrate was washed in the same manner as in Example 1, the coating solution D-1 for the undercoat layer was prepared.
4 to 4, undercoat layers having film thicknesses of 1 μm, 5 μm, and 8 μm were applied by the dip method and dried. Further, a charge generation layer (0.3 μm) and a charge transport layer (20 μm) are provided on the undercoat layer using the above-mentioned charge generation layer coating liquid and charge transport layer coating liquid, and the photoreceptor [D-1 ]-[D4-3] were produced.

Examples 23 to 26, Comparative Examples 33 to 43 [Preparation of coating liquid for charge transport layer] 10 parts by weight of the hydrazone compound represented by the above-mentioned compound CT-28 as a charge transport material, and polycarbonate as a resin binder (trade name Pane). Light L1225: Teijin Chemicals Ltd. 10 parts by weight, 2,6, -di-t-butylhydroxytoluene 0.4 parts by weight as an antioxidant, dichloromethane 80 parts by weight, silicone oil KP-340 0.06 By dissolving in parts by weight, a coating liquid II for the charge transport layer was prepared.

[Production of Photoreceptor] As in Example 1, coating solutions A-1 to A-5 for the undercoat layer were formed on an aluminum substrate.
An undercoat layer having a film thickness of 0.5 μm, 1 μm, and 2 μm was applied by the dipping method and dried. Then, after forming a charge generation layer (0.3 μm) on the undercoat layer with the above coating liquid for the charge generation layer,
Further, a charge transport layer (20 μm) is provided thereon by the coating liquid II for the charge transport layer, and the photoconductors [E1-1] to [E5] are provided.
~ 3] were produced.

Evaluation Condition of Photoreceptor After visually evaluating the uniformity of the charge generation layer of the photoreceptor, the photoreceptor was mounted in an evaluation machine of a laser printer, and the normal temperature and humidity (20 ° C., 60% RH; RR), low temperature and low humidity (5 ° C., 30% RH, hereinafter referred to as LL), high temperature and high humidity (35 ° C., 85% RH, hereinafter referred to as HH) for 1 hour or more, and then obtained by reversal development The images obtained were evaluated. Further, a running test was performed 10,000 times in an RR atmosphere to evaluate the images obtained by the change in the light potential (VL) and the dark potential (VO) and the inversion phenomenon.

With respect to the adhesiveness, 25 squares having a side of 2 mm were drawn on the prepared photoconductor with a cutter knife, and a peeling test was performed with cellophane tape. The obtained results are shown in Tables 10 to 14 below. The criteria for the image evaluation results in each table are as follows. K indicates the generation level of minute black dots when a blank sheet is printed. W indicates the generation level of minute white dots when black paper is printed. △ is a level that is slightly generated but practically no problem. X markedly occurred.

[0060]

[Table 10]

[0061]

[Table 11]

[0062]

[Table 12]

[0063]

[Table 13]

[0064]

[Table 14]

As can be seen from Tables 10 to 13, the photoconductors of the examples have a smaller bright part potential (VL) immediately after the start of the test than the photoconductors of the comparative examples and are bright even after 10,000 running tests. There is little change in the partial potential (VL) and the dark portion potential (V0), and the image obtained by the inversion phenomenon is also good.

Further, as is clear from the reference examples shown in Table 14, a specific distyryl compound is used as a charge transport material in the charge transport layer in order to achieve low residual potential and high repetitive stability with low residual potential. It turns out that plays an important role in.

[0067]

EFFECT OF THE INVENTION The photoconductor to which the present invention is applied has very few image defects and shows stable images (high chargeability and low light portion potential) under the environment of 5 ° C. to 35 ° C. and 0 to 95% RH. Obtained,
It has stable chargeability in repeated tests and a low bright portion potential, does not cause image defects due to light interference, and has sufficient adhesive force with the conductive substrate and the photosensitive layer.

[Brief description of drawings]

FIG. 1 is a cross-sectional structural view of a negative charging type laminated type photographic photosensitive member according to an example of the present invention.

FIG. 2 is a cross-sectional structural view of a positive charging type laminated type photoconductor according to another example of the present invention.

FIG. 3 is a sectional structural view of a positive charging type single layer type photographic photoreceptor according to still another example of the present invention.

[Explanation of symbols]

 1, 11, 21 Conductive substrate 2, 12, 22 Undercoat layer 3, 13, 23 Charge generation layer 4, 14 Charge transport layer 15 Overcoat layer

Claims (5)

[Claims] 1. An electrophotographic organic photoreceptor comprising a conductive substrate, an undercoat layer and a photosensitive layer, wherein the undercoat layer is N- (alkoxymethyl) nylon of copolymerized nylon containing nylon 12 as a main component. Or a mixture of the nylon and an alcohol-soluble copolymerized nylon, wherein the N-alkoxymethylation ratio of the nylon as a whole is 1% or more and less than 15%, and the thickness of the undercoat layer is 1. An organic photoconductor for electrophotography, which has a thickness of 5 μm or less. 2. The undercoat layer in the organic photoconductor for electrophotography according to claim 1, which is produced by reacting titanium tetrachloride with hydrogen and oxygen, and has an anatase content of 50 to 50.
90%, the remainder having a rutile type crystal structure, and having a particle size of 70 nm or less, titanium dioxide is dispersed in an amount of 10 to 300 parts with respect to 100 parts by weight of nylon, and the thickness of the undercoat layer is 7 μm. An organic photoconductor for electrophotography, comprising: 3. An organic photoconductor for electrophotography comprising a conductive substrate, an undercoat layer and a photosensitive layer, wherein the undercoat layer has the following formula (1) containing nylon 12 as a main component: (X ¹ in the formula (1) is expressed by the following formulas (2) to (4), (In the formulas (2) to (4), m and n are integers of 2 to 20, q is an integer of 0 to 20, R ¹ , R ² and R ⁵ are alkylene groups and R is an integer.
³ , R ⁴ represents an alkyl group), a modified copolymerized nylon having a structure represented by the formula (1) selected from the group consisting of substituents represented by (1) or the nylon and an alcohol-soluble copolymerized nylon. An organic photoconductor for electrophotography, characterized in that the N-methyl modification ratio of the whole nylon is 1% or more and less than 20%, and the film thickness of the nylon layer is 1.5 μm or less. 4. The undercoat layer in the organic photoconductor for electrophotography according to claim 3, which is produced by reacting titanium tetrachloride with hydrogen and oxygen and has an anatase content of 50 to 50.
90%, the remainder having a rutile type crystal structure, and having a particle size of 70 nm or less, titanium dioxide is dispersed in an amount of 10 to 300 parts with respect to 100 parts by weight of nylon, and the thickness of the undercoat layer is 7 μm. An organic photoconductor for electrophotography, comprising: 5. The photosensitive layer is a laminated type having a charge generation layer and a charge transport layer, the charge generation agent in the charge generation layer is a phthalocyanine-based organic pigment, and the charge transport material in the charge transport layer is formula, (In the formula, R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are a hydrogen atom, a halogen atom, an alkoxy group or an optionally substituted alkyl group or an aryl group, and R ¹³ is a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group. The organic photoconductor for electrophotography according to any one of claims 1 to 4, comprising a distyryl compound represented by the formula (1).