JPS63170651A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a photosensitive body high in sensitivity, small in electric fatigue at the time of repeated uses, and superior in lightfastness by using a specified enamine compound for an electric charge transfer layer. CONSTITUTION:A photosensitive layer formed on a conductive substrate contains as a charge carrier transfer agent the enamine compound represented by formula (I) in which R1 is methyl or ethyl, and R2 is methyl or H substituted at the para- or meta-position. This enamine compound is dispersed or added together with a binder, a sensitizing dye or pigment, or a charge generating agent to form a single layer type photosensitive body or added to the charge transfer layer adjacent to the charge generating layer together with the binder to form the laminate type photosensitive body, thus permitting the obtained charge transfer layer to be high in sensitivity and durability.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of application for smoked confectionery) The present invention relates to a photoreceptor for electrophotography, and more specifically,
The present invention relates to an element for a cylindrical device, which contains 1% of an enamine 16 compound as a charge carrier transfer agent in a four-electrophotosensitive layer formed on a conductive substrate.

(Prior Art) Conventionally, photoconductive materials for photoreceptors used in electrophotography include inorganic materials such as selenium, cadmium sulfide, and zinc oxide. The "electrophotographic method" referred to here is a general method in which the photosensitive material is negatively charged by corona discharge in a dark place, and then all charges in the exposed area are selectively erased by image exposure. , a so-called electrostatic latent image is obtained, and in this latent image area.

Positively or negatively charged to make nine colored fine particles layer-resistant.

This is an image forming method that develops and visualizes images.

Characteristics required of a photoreceptor used in such an electrophotographic method are that it can be charged to a sufficient potential in a dark place, (2) that it can be charged to a sufficient potential in a dark place, and (3) that it can be charged to a sufficient potential for a sufficient time in a dark place; When irradiated with light, the charge must disappear quickly.

In recent years, in order to compensate for these drawbacks, organic electrophotographic photoreceptors using various organic substances have been proposed. The organic electrophotographic photoreceptor has (i) a mA amount, (+i
) Selection of 01D material, which has good processability and can be processed into films, sheets, and drums.

The combination has the following characteristics: 1 spectral sensitivity, easy sensitivity design, non-toxic substances can be used, and users can handle and dispose of it themselves. Many are already in practical use.

For example, BoIJ-N-vinylcarbazole,! :2,
4.7-Dolinitrofluorene? A photoreceptor consisting of poly-N-vinylcarbazole sensitized with a biryllium salt and the following (U.S. Pat. Photoreceptors made of eutectic complexes (% opening: 47-10735) are known, and Toku Ki & Kon has developed a multilayer structure that separates charge generation and charge movement into separate functions, making it possible to develop organic photoreceptors. Developments related to the body are actively being carried out.

The advantage of the functionally separated type is that the performance of the photoreceptor can be varied by selecting the charge generation layer and the charge transfer layer separately. for example.

By selecting the charge generation layer, a high sensitivity ratio and a panchromatic ratio can be achieved, and by selecting the charge transport layer, durability and sacrificial properties can be achieved. Based on this idea, it has already entered the practical stage.

One in which dimethylperylimide is used as a charge generation layer and oxadiazole is used as a charge transfer layer [J, Appl, Photo.

Eng., 4118 (1978)], Squarylium.

There are known materials in which a charge generation layer is made of chlorodiane blue or the like and a charge transfer layer is made entirely of pyrazoline (Japanese Patent Application Laid-Open Nos. 49-105536 and 1982-105537). All of them have unique characteristics as photoreceptors for electrophotography,
The electrophotographic method has been applied not only to copying machines but also to various types of printers such as laser printers, LED printers, and liquid crystal printers.

In addition, as its applications have expanded to include colorization,
The characteristics required of photoreceptors are also slightly different. For this reason, there are still many charge generating agents available today.

Charge transfer agents have been developed.

(Problems to be Solved by the Invention) Although inorganic substances such as those described above have many characteristics that suit the various required characteristics described above, they also have various drawbacks. It's hilarious.

For example, selenium, which is currently widely used, is difficult to mold, is expensive to manufacture, is not legible, is difficult to process into a belt, and furthermore, its properties deteriorate due to heat and humidity. Next.

Sufficient care must be taken when handling it. The major disadvantage of selenium is its toxicity, so you need to be very careful when handling the photoreceptor t''.My friend,
General users cannot dispose of, incinerate, or otherwise dispose of used photoreceptors.

This is a major obstacle to the widespread use of copying machines and printers that utilize electrophotography. In addition to selenium, cadmium sulfide and zinc oxide can also be dispersed in a binder as an inorganic substance and used as a photoreceptor.

However, these have many drawbacks in mechanical properties such as hardness, friction resistance, and tensile strength, and it is necessary to use properties that remain unresolved or have many problems for long-term repeated use. .

(Means for Solving the Problems) The present invention aims to obtain a charge transfer node with S6 sensitivity and high durability. However, the present inventors have discovered that they have excellent storage stability and stability against light irradiation, leading to the creation of the present invention.

Many enamine compounds are known, and many pioneering examples of functionally separated photoreceptors with charge transfer layers have been proposed, but there are few examples of enamine compounds that have been put to practical use. for example,
Journal of Imaging Science
Vol 29, A I, P 7, Jan,
/ Feb, (1985), its representative enamine compounds are.

N-(2,2-Bis(4-Methoxyphen
yl ) ethylene]-4-Methoxy-N
-(4-Methoxyphenyl) -Ben
zenamine N-(2,2-Bis (4-Ethoxypheny
l)ethenyl)-4-Methoxy-
N-(4-Methoxyphenyl)-Benz
An example is described in which enamine or the like is used as a charge transfer layer. However, the general formula CI) as an adjunct of the present invention is shown.
There are no examples disclosed that disclose an enamine structure in which an alkyl group such as a methyl group is substituted with a phenyl ring. Furthermore, it is pointed out that the enamine compound charge transport layer in the report requires further improvement in terms of sensitivity, repeated use characteristics, and light resistance.

In view of the above-mentioned circumstances, the present inventors conducted intensive research and found that by using a specified nine-enamine ratio compound represented by the following general formula CI) in the charge transfer layer, the enamine It has been found that a significantly improved photoreceptor can be obtained compared to the compound.

(However, R1 is a methyl group or ethyl IS, and Rt is a methyl group substituted at the meta position or a hydrogen atom.) The specified enamine compounds useful in the present invention are s
When R1 is a methyl group, the primary 2.2-(4,4'-dimethoxyphenyl)acetaldehyde is 2.2-(4,4
An aldehyde f arsenate such as '-jetoxyphenyl)acetaldehyde and an aromatic amine such as p,p'-ditolylamine or m,m'-ditolylamine or diphenylamine are combined in a reaction solvent such as benzene or toluene to form p-1 It can be obtained by carrying out a dehydration reaction in the presence of luenesulfonic acid by a known method. That is,
The enamine compound is shown below.

N-(2,2-Bis(4-Methoxyphe
nyl) ethylene)-4-Methyl-
N-(4-Methylphenyl)-Ben
zenamine N-(2,2-Bis (4-Methoxyphe
nyl) ethenyl]-3-Methyl-
N-(3-Methylphenyl)-Ben
zenamine N-(2,2-Bis (4-Methoxyphe
nyl)ethenyl)-N-Phenyl-B
enzenamineN-4:2.2-Bis (4-
Ethoxyp! '1enyl)ethenyl]-
4-Methyl-N-(4-Methylphe
nyl ) -Benzenamine N -[2,2-Bis (4-Ethoxyphen
yl)ethenyl]-3-Methyl-
N-(3-Methylphenyl)-Ben
zenamineN-(2,2-Bis(4-Et
hoxyphenyl) ethenyl]-N-p
henyl-Benzenamine Furthermore, the general formula (
1) A propyl group or a butyl group having 3 or more carbon atoms may be introduced into s R1 in enamine compounds that can be easily predicted.

- In the present invention, a methyl group was used for R1, but
Ethyl group, propyl group, butyl group 1 Para position, me
An enamine structure introduced at the tha position is also expected. for example.

N-[2,2-Bis (4-Methoxyphe
nyl) ethenyl]-4-Propyl-
N-(4-Propylphenyl)-Benz
enamineN −[2,2-Bis (4-Eth
oxyphenyl)ethenyl]-S-Pr
opyl-N-(5-Propylphenyl
) -BenzenamineN -[2,2-Bis
(4-Methoxyphenyl) ethene
yl:1-4-Butyl-N-(4-Butyl
lphenyl) -BenzenamineN-
[2,2-Bis (4-Ethoxyphenyl
) ethenyl)-3-Butyl-N-(5-B
utilphenyl)-BenzenamineN
-[: 2, 2-Bis (4-Propoxyp
(henyl) ethenyl]-4-Propyl
-N-(4-Propylphenyl)-Ben
Examples include zenaone.

Above is the enamine compound used in the present invention.

It can be used in the same way as conventional charge transfer agents, for example, along with a binder, as a sensitizing dye.

A photoreceptor in which a sensitizing pigment or a charge generating agent is dispersed or added, or a photoreceptor that is laminated adjacent to a charge generating layer together with a binder, can be prepared as a photosensitive member.

In the present invention, when the aforementioned tomo enamine compound is used as a charge transfer layer of a photoreceptor, it is possible to obtain a photoreceptor with particularly high sensitivity, less electrical fatigue during repeated use, and excellent light resistance. can.

The layer structure of the functional An photoreceptor includes conductive layer 1171m, charge generation layer, 11! A cargo transport layer is essential, and a barrier layer and a protective layer can be provided as necessary.

The stacking order of the 4'vL layer, the charge generation layer, and the charge transfer layer may be arbitrary, but the charge generation layer and the charge transfer layer must be adjacent to each other.

As the conductive layer, conventionally used conductive materials 1
For example, an aluminum plate, aluminum-deposited plastic, or a plastic material coated with conductive paint can be used.

As a charge generation material used for the charge generation layer.

Any material that absorbs light and generates charge carriers with high efficiency can be used.

Preferred materials include selenium and selenium tellurium.

Inorganic materials such as cadmium sulfide, biryllium salts.

Organic materials such as squarylium salts, azo pigments, cyanine pigments, quinone pigments, and 7-thalocyanine pigments can be used. When these materials are steamed, a charge is generated by copying cloth from the dispersion! −.

The thickness of this charge generation layer can range from 0.01 to 5 microns.

A charge transfer layer is provided on the specific charge generation layer by any of the above methods, and the enamine compound of the present invention is
A charge transfer layer is obtained by coating and drying a solution of this and an appropriate binder dissolved in an organic solvent.

As the binder, acrylic resin, polycarbonate resin, polyester resin, polysulfone resin, etc. can be used. The ratio of the enamine compound of the present invention to the binder can be in the range of 2 parts by weight to 0.5 parts by weight based on INt part of the enamine.

The thickness of the charge transfer layer may range from 5 to 30 microns.

(Action of the invention) The electrophotographic photoreceptor thus obtained can be used in electrophotographic copying machines, laser printers, LED printers, LC
It can be applied to many fields such as D printers, 14L photo plate master plates, and electrophotographic microfilms.

The photosensitive characteristics of the obtained photoreceptor were 5p-428 manufactured by Kawaguchi Denki.
It is evaluated using a K test machine as follows.

First, the photoreceptor was charged with -5.6KV corona radiation, and left in a dark place until a constant voltage was reached.

Next, a tungsten lamp was used to irradiate the surface of the photoreceptor with light of 20 lux, and one surface of the mold became 1/2 of the level before irradiation.
Sensitivity is measured by measuring the time it takes for the luminance to reach 1 second. Mayu.

Spectral sensitivity is the halved exposure energy μJule/d't-, which is the sum of the energy intensity μW/d of the photoreceptor surface after 1 minute of light and the time it takes for the surface potential to become 1/2.
The reciprocal of this is called the spectral sensitivity.

The fatigue characteristics during repeated use were similarly measured using a 5P-428 tester manufactured by Kawaguchi Electric, with a corona discharge of -5.6 KV and a corona linear velocity of 207 Fl/If! 1, the surface of the photoreceptor is charged, left for 0.5 seconds, and the charged potential V at that time. t-measure. Subsequently, the surface of the photoreceptor is irradiated with light having a surface illuminance of 500 lux for a total of 00 seconds. This operation 2
．． Reminisce for 5 seconds/cycle.

By repeating this operation, the charging capacity (v
Observe changes in o) and changes in residual potential (vR).

Evaluate fatigue characteristics as cyclic characteristics.

It has been found that the electrophotographic photoreceptor according to the present invention has superior sensitivity and repeatability characteristics compared to conventional photoreceptors.

(Examples) Hereinafter, the present invention will be explained in detail with reference to Examples, Comparative Examples, and Synthesis Examples. In these Examples, Comparative Examples and Synthesis Examples, 1% of Keibonbe means t% by weight.

Synthesis Example 1 A total of 2.661 2,2-(4,4'-dimethoxydiphenyl)acetaldehyde was taken in an eggplant-shaped flask (100 d) containing an enamine compound. 91% of the reaction solvent toluene was added and dissolved with stirring. , 1.77 tff of 4,4'-ditolylamine was added, and 0.11 tff of balatoluene sulfonate was added.
While stirring, the reaction was carried out for 2 hours at the boiling point of toluene. After completion of 6 reactions, 1 reaction solution was cooled, washed with water, dehydrated, toluene removed, and column separated (bath medium: toluene, packing material Wa
ko gel C-200).

After reconsolidation, white crystals are obtained with a concentration of 83 mol.

The structure of the obtained 7' (crystal) was confirmed by NMR analysis.

■NMR analysis (CdC15) Peak position 2.21 (S, 6H), 3.75 (D, 6
H).

(1'1') 6.55-7.2 (M, 17H) @ melting point
124.0 CO elemental analysis value carbon hydrogen % theoretical value B2.76 6,67 3.21 measured value 82
．． 69 6.57 5.25 Synthesis Example 2.3 An enamine compound is synthesized using the same reaction procedure as in Synthesis Example 1. However, it is synthesized by reacting a primary amine compound.

Synthesis Example 25. Add 1.779 of 5'-ditolylamine,
A similar operation was carried out, and the yield was lower.

Synthesis Example 3 In addition to 1.52 f' of diphenylamine.

It rots by the same operation, yield is 85 mol. It is.

Synthesis Example 4 The enamine ratio compound was entirely synthesized by the same reaction procedure as in Synthesis Example 1. However, the aldehyde ratio is 2.2-(4,4'-jethoxydiphenyl)acetaldehyde 1.76/
, the amine encounter is 4,4'-ditolylamine 1,179
Synthesize by reacting with The yield was 72 moles.

Synthesis Example 5 An enamine compound is synthesized using the same procedure as in Synthesis Example 4.
The amine compound was synthesized by reacting with 1.179 g of 3,3'-ditolylamine. The yield was 62 moles.

Synthesis Example 6 An enamine compound was synthesized in the same manner as in Synthesis Example 4, except that Aba716 compound was synthesized by reacting with diphenylamine 1,019. The yield was 71 moles.

The above 1 synthesis examples 2 to 6t are summarized and the results of NMR analysis and analysis of 9 elements are shown in Table s1.

Table 1 Example 1 Creation of a charge generation layer in the production of a functionally separated photoreceptor A 1% methanol solution of Tone's soluble polyamide (0M4001) was coated on a 100μ thick aluminum plate and dried.
A single barrier layer with a thickness of 0.05μ was provided.

On top of this barrier layer, a charge generating layer of gold was deposited as described below.

Add 1% chlordian blue represented by the above formula to tetrachloroethane, and add 0% butyral resin to the colander.
The 5% additive was dispersed using a ball mill. This dispersion was applied onto the barrier aluminum plate and dried to form a charge generating layer with a thickness of 0.2 .mu.m.

(b) Squarylium 17i30- having the following structure
of tetrahydrofuran and dispersed in a ball mill to prepare a dispersion. The coating was applied and dried in the same manner as in (a) to form a charge generation layer having a thickness of 0.01 μm.

(C) Vanadyl phthalocyanine 11000A was deposited on the aluminum substrate on which the barrier layer was provided to form a charge generation layer.

(d) Chloraluminum phthalocyanine chloride was vapor-deposited to a thickness of 50× on the aluminum plate provided with the above barrier layer. This vapor deposited film.

It was immersed in 50 rnt of toluene containing 500 ml of water and left at room temperature for 60 minutes to form a charge generation layer.

(e) 1 part of m-phthalocyanine (manufactured by Toyo Ink Co., Ltd., Lionol ES) and 0.5 part of acrylic resin (manufactured by Dainippon Ink Co., Ltd., Acrydic A-801) were mixed in 1,2-dichloroethane to give a total of 5 parts. Add and thoroughly disperse in a ball mill. The milling solution is diluted with 1,2-dichloroethane to a solid content concentration of 0.75%. This dispersion was applied to a barrier aluminum plate and dried to a thickness of 10 mm.
00AQ) i (Created a metal layer.

Example 2 Preparation of coating liquid for charge transfer layer The enamines prepared in Synthesis Examples 1 to 6 were combined with the following binders in a ratio of 1 part to 1 part, and mixed, respectively, to obtain 1.2-
The mixture was dissolved in 10 parts of dichloroethane to prepare a charge transfer layer coating solution.

(I) Methyl methacrylate resin (Asahi F.Hisei Delbet) l Polycarbonate resin (Mitsubishi Gas Chemical Kneepilon E
-2000) l Styrene acrylic resin (Nippon Steel Chemical MS
-600) Examples 3 to 92 The coating solution prepared in Example 2 was applied at 70C onto the charge generation layer prepared in (a) to (e) of Example 1.

After removing the solvent and pre-drying, it is further dried at 80C for 60 minutes. A photoreceptor having a film thickness of 15 μm was prepared under these conditions. Examples of photoreceptor preparation are shown in Table 2.

Table 2 Table (2) A coating liquid was prepared in the same manner as in Example 6. Photoreceptors prepared by combining this coating liquid and the charge generation layer of Example 5 are referred to as Comparative Examples 1 to 5.

Hydrazone compound (comparative example) Coating liquid: 1 part of hydrazone compound, 1 part of polycarbonate (Niepilon E-2000 manufactured by Mitsubishi Gashi), 1 part of 10 parts
．． Dissolve in 2-dichloroethane.

Performance of Examples and Comparative Examples The performance of each photoreceptor of Examples and Comparative Examples was measured using the measuring device described above (measurement using white light).

The results are shown in Table 5.

Table 3 Furthermore, using a 790 nm spectral light source, each photoreceptor of Examples and Comparative Examples was measured. The result is the fourth
Shown in the table.

Table 4 (Effect of the invention) The enamine compound represented by general formula (I) of the present invention is.

As shown in the examples, its performance is not only excellent in both initial performance and performance after repetition, but also in sensitivity and repetition resistance. It turned out to be an excellent photoreceptor.

Claims (1)

[Scope of Claims] An electrophotographic photoreceptor comprising an enamine compound represented by the following general formula (I) as a charge carrier transfer agent in a photosensitive layer formed on a conductive support. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) (However, R_1 represents a methyl or ethyl group, and R_2 represents a methyl group substituted at the para or meta position, or a hydrogen atom.)