JPH012059A - Photoconductive coating and electrophotographic photoreceptor using the same - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a photoconductive coating containing a novel organic photoconductive compound and an electrophotographic photoreceptor using the same.

"Prior Art and its Problems" As electrophotographic photoreceptors, those having a photosensitive layer containing an inorganic photoconductive compound such as selenium, zinc oxide, or cadmium sulfide as a main component are widely known. However, these are not necessarily satisfactory in terms of properties such as thermal stability and durability, and they also pose problems in production and handling due to their toxicity.

On the other hand, electrophotographic photoreceptors having a photosensitive layer containing an organic photoconductive compound as a main component are relatively easy to manufacture, inexpensive, and easy to handle. It has attracted attention in recent years because it has many advantages, such as being easy to use and generally having better thermal stability than selenium photoreceptors. Poly-N-vinylcarbazole is the most well-known such organic photoconductive compound;
．． An electrophotographic photoreceptor having a photosensitive layer containing as a main component a charge transfer complex formed from a Lewis acid such as 7-dolinitro and 9-fluorenone has already been put into practical use.

Furthermore, electrophotographic photoreceptors are known that have a laminated quiz or dispersion type functionally separated photosensitive layer in which the carrier generation function and the carrier transport function of the photoconductor are assigned to separate substances, respectively. For example, an electrophotographic photoreceptor having a photosensitive layer consisting of a carrier generation layer made of an amorphous selenium thin film and a carrier transport layer containing poly-N-vinylcarbazole as a main component has already been put into practical use.

Furthermore, attempts have been made to use organic photoconductive compounds as both the carrier-generating substance and the carrier-transporting substance in electrophotographic photoreceptors having the above-mentioned functionally separated photosensitive layer.

In this case, carrier generating substances include azo dyes, phthalocyanine dyes, anthraquinone dyes, perylene dyes,
Cyanine dyes, chiapyrylium dyes, squareium dyes, etc. are known. Further, as carrier transport substances, amine derivatives, oxazole derivatives, oxadiazole derivatives, triphenylmethane derivatives, etc. are known.

These carrier-generating substances and carrier-transporting substances are
When it does not have the ability to form a film by itself, it is used in combination with various binders to form a film. Then, an electrophotographic photoreceptor is formed by laminating a layer having a carrier-generating substance and a layer having a carrier-transporting substance on a conductive support, or it contains a carrier-generating substance and a carrier-transporting substance in a dispersed state. 2. Description of the Related Art Electrophotographic photoreceptors formed of layers are known.

However, electrophotographic photoreceptors using organic photoconductive compounds as carrier generating substances still have lower photoconductive sensitivity and durability than those using inorganic photoconductive compounds. Currently, there are very few products that can be put into practical use.

"Object of the Invention" An object of the present invention is to provide a highly sensitive photoconductive coating and an electrophotographic photoreceptor using the same by employing a novel organic photoconductive compound.

"Structure of the Invention" The photoconductive film according to the present invention is characterized in that it contains at least -tilt of a bisazo pigment represented by the following general formula (1).

(Hereinafter, blank space) (In the formula, A represents a hydrogen atom, a lower alkyl group, an aryl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyl group, a halogen atom, or a monovalent organic residue. represents a group, X represents an atomic group necessary to form a monosubstituted or unsubstituted hydrocarbon or heteroaromatic ring by condensation with a benzene ring, and B represents the same or different. may be,
Furthermore, R1 and R2 represent a hydrogen atom, a lower alkyl group, an aryl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyl group, a halogen atom, or a monovalent organic residue. The bisazo pigment represented by the general formula (1) is placed on a conductive support at least -f! The present invention is characterized by providing a photosensitive layer having a photoconductive coating containing .

Until now, there has been no attempt to use the dosuazo pigment represented by the general formula (+) as a photoconductive metal compound for electrophotography, and the present inventors have proposed using this compound as a photoconductive compound for electrophotography, particularly as a carrier. It was discovered that an electrophotographic photoreceptor with excellent sensitivity can be obtained by using it as a generating substance,
This has led to the completion of the present invention.

Specific examples of the compound represented by the general formula (1) include the following.

In the above formula (2), examples of combinations of R1° to R3° are shown in Table 1.

Examples of combinations of B in the above formula (3) are shown in Table 2.

(Hereinafter, blank spaces) 1. The compound represented by the general formula (1) can be synthesized, for example, by a reaction formula as shown in FIG. In addition, in FIG. 7, the symbols in the formula have the same meanings as those in the general formula (1). For details of this synthesis method, please refer to “Practical
al Heterocyclic Chemistry
″.

Academic Press (1968) P 9
It is described in 3.

The electrophotographic photoreceptor of the present invention uses the organic photoconductive compound represented by the general formula (1) as a carrier generating substance, and can have, for example, the following structure.

As shown in FIG. 1 or 2, a laminate of a carrier generation layer 2 containing a carrier generation substance as a main component and a carrier transport layer 3 containing a carrier transport substance as a main component on a conductive support 1 is formed. A photosensitive layer 4 is provided. FIG. 1 shows a carrier transport layer 3v on the carrier generation layer 2! This is an example provided,
FIG. 2 shows an example in which a carrier generation layer 2 is provided on a carrier transport layer 3.

As shown in FIG. 3 or 4, a photosensitive layer 4 similar to that described above is provided on a conductive support 1 with an intermediate layer 5 interposed therebetween.

As shown in FIG. 5 or 6, a fine particle carrier generating substance 7 is contained in a layer 6 mainly composed of a carrier transporting substance.
A photosensitive layer 4 formed by dispersing is directly on the conductive support 1,
Alternatively, it is provided via the intermediate layer 5.

The conductive support 1 may be a metal plate, or paper or plastic made conductive by coating, vapor depositing, or laminating a conductive compound such as a conductive polymer or indium oxide, or a metal thin film such as aluminum, palladium, or gold. is used.

The carrier generation layer 2 is formed by turning the carrier generation substance represented by the general formula (1) into fine particles in a dispersion medium using a ball mill, a homomixer, a sand mill, a colloid mill, etc.
If necessary, a dispersion obtained by mixing and dispersing with a binder is applied, or a solution obtained by dissolving a carrier-generating substance in a binder in a solvent is applied by dipping method, spray method,
It can be formed by coating using a method such as a coating method.

In this case, examples of the binder include phenol resin, polyester resin, vinyl acetate resin, polycarbonate resin, polypeptide resin, cellulose resin, polyvinylpyrrolidone, polyethylene oxide, polyvinyl chloride resin, starch, polyvinyl alcohol, acrylic resin, etc. Polymer resin, methacrylic copolymer resin, silicone resin,
Polyacrylonitrile copolymer resins, polyacrylamide, poly and nylbutyral, etc. can be used.

Note that the carrier generation layer 2 can also be formed by forming a compound represented by the general formula (1) into a thin film by a method such as vacuum deposition.

The carrier transport layer 3 can be formed by dispersing or dissolving a carrier transport substance in a binder similar to the above and coating it. In the present invention, the carrier transport substance is not particularly limited, but may include, for example, amine derivatives, oxazole, etc. Derivatives, oxadiazole derivatives, triphenylmethane derivatives, etc. can be used.

The intermediate layer 5 disposed between the conductive support 1 and the photosensitive layer 4 has a barrier function and an adhesive function, and is made of, for example, casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid. It can be formed from copolymers, polyamides (nylon 6, nylon 66, nylon 610, copolymerized nylons, alkoxymethylated nylons, etc.), polyurethane, gelatin, aluminum oxide, and the like.

Further, the photosensitive layer 4 is formed by dispersing a fine particulate carrier generating substance 7 in a layer 6 mainly composed of a carrier transporting substance, by dispersing or dissolving the carrier transporting substance in the binder as described above, It can be formed by applying a liquid in which a carrier generating substance is roughly dispersed.

"Examples of the invention" Examples 1 to 10 2 parts by weight of butyral resin and 10 parts by weight of isopropyl alcohol
5 parts by weight of the 10 types of throat azo pigments listed in the table below were ground in a Pall mill and dispersed in a solution containing 0 parts by weight to prepare 10 types of coating liquids. and,
Each coating solution was applied onto a 50 um AI plate using a doctor blade so that the film thickness after drying would be 0.3 um, and dried to form a charge generation layer.

Next, 5 parts by weight of a hydrazone compound represented by the following structural formula and 5 parts by weight of polycarbazole were dissolved in 70 parts by weight of monochlorobenzene, and this was applied on the charge generation layer to a dry film thickness of 20 um. It was coated using a doctor blade so that the charge transport layer was formed and dried to form a charge transport layer.

This is how I got 107! Next to the electrophotographic photoreceptor of
00 type), corona charging was performed at 26 V using the screen-ink method, and then dark decay was observed for 5 seconds, and the illuminance was set to 151 V.
The photoelectric properties were evaluated by observing the optical attenuation during 5-second periodic exposure of UX. Table 3 shows the results of initial charging potential (Va), sensitivity (E172), and residual potential (Va) measured using this device.

(Hereinafter, blank space) Table M3 However, the sensitivity is shown as O=good, Δ=fair, and ×: bad.

"Effects of the Invention" As explained above, according to the present invention, a photoconductive film having high sensitivity photoconductivity can be obtained by using the novel hisazo pigment represented by the general formula (1). can. Moreover, by using the novel bisazo pigment represented by the general formula (1), an electrophotographic photoreceptor with good characteristics can be obtained using the resulting highly sensitive photoconductive film. Therefore, the present invention provides an electrophotographic copying machine, a laser beam printer, 1. It can be widely applied to LED blink-2 CRT blink or other electrophotographic applications in general.

[Brief explanation of drawings]

FIG. 1, FIG. 2, FIG. 3, FIG. FIG. 2 is a diagram showing a reaction formula for synthesizing the suazo pigment used. Patent applicant Alps Electric Co., Ltd.

Claims (2)

[Claims] (1) A photoconductive film characterized by containing at least one bisazo pigment represented by the following general formula (1). ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(1) (In the formula, A is: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲Mathematical formulas, chemical formulas, tables, etc. etc. ▼ where R represents a hydrogen atom, a lower alkyl group, an aryl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyl group, a halogen atom or a monovalent organic residue. represents an atomic group necessary to form a substituted or unsubstituted hydrocarbon or heteroaromatic ring. R_1 and R_2 are hydrogen atoms, lower alkyl groups, aryl groups, alkoxycarbonyl groups, aryloxycarbonyl groups, acyl groups, halogen atoms, or monovalent organic residues. ) (2) An electrophotographic photoreceptor comprising, on a conductive support, a photosensitive layer having a photoconductive coating containing at least one type of bisazo pigment represented by the following general formula (1). ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(1) (In the formula, A is: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲Mathematical formulas, chemical formulas, tables, etc. etc. ▼ where R represents a hydrogen atom, a lower alkyl group, an aryl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyl group, a halogen atom or a monovalent organic residue. represents an atomic group necessary to form a substituted or unsubstituted hydrocarbon or heteroaromatic ring. R_1 and R_2 are hydrogen atoms, lower alkyl groups, aryl groups, alkoxycarbonyl groups, aryloxycarbonyl groups, acyl groups, halogen atoms, or monovalent organic residues. )