JPH012053A - 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 as a main component an inorganic photoconductive compound such as selenium, zinc oxide, or cadmium sulfide have been widely known. However, these are not necessarily satisfactory in terms of properties such as thermal stability and durability, and furthermore, due to their toxicity, they are difficult to manufacture.
There were also problems in handling.

On the other hand, an electrophotographic photoreceptor having a photosensitive layer containing a ζ organic photoconductive compound as a main component is relatively easy to manufacture, inexpensive, and easy to handle; It has attracted attention in recent years because it has many advantages such as superior thermal stability. Poly-N-vinylcarbazole is the most well-known such organic photoconductive compound;
．． Electrophotographic photoreceptors having a photosensitive layer containing as a main component an electrostatic transfer complex formed from a Lewis acid such as 7-t-unitro-9-fluorenone have already been put to practical use.

Furthermore, electrophotographic photoreceptors are known that have a laminated quib 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 the electrophotographic photoconductor having the above-mentioned functionally separated type photoconductor R.

In this case, carrier-generating substances include azo dyes, fuccyanine dyes, anthraquinone dyes, perylene dyes,
Known examples include cyanine dyes, thiadolylium dyes, and squareium dyes. 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 photoconductivity sensitivity and durability than those using inorganic photoconductive compounds. Currently, there are very few products that can be put into practical use because they are inferior in terms of both.

"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 by containing at least one type of bisazo pigment represented by the following general formula (1).

(In the formula, Cp represents, 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, and X represents a benzene ring. Represents an atomic group necessary for condensing with M to form an M-substituted or silent hydrocarbon or heteroaromatic ring, R may be the same or different, and R6 and R2 are hydrogen. atom, lower alkyl group, aryl group, alkoxycarbonyl group, aryloxycarbonyl group, acyl group, halogen atom or 1
Furthermore, the electrophotographic photoreceptor according to the present invention includes a photoconductive material containing at least one kind of suazo additive represented by the general formula (1) above, on a conductive support. It is characterized by providing a photosensitive layer having a coating.

Until now, there has been no attempt to use the bisazo pigment represented by the general formula (1) as a photoconductive compound for electrophotography.
The present inventor has developed this compound into a photoconductive compound for electrophotography,
In particular, the inventors have discovered that an electrophotographic photoreceptor with excellent sensitivity can be obtained by using it as a calice generating substance, and have completed the present invention.

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

70. Examples of combinations of 81 to R3 in the above formula (2) are shown in Table 1.

Examples of combinations of Cp 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 FIG. 7, the symbols in the formula have the same meanings as those in the general formula (1). Details of this synthesis method can be found in J. Schimi.
dt, A, to: fflmpf, Ber,, 36.3
745 (1903), J. Schmidt, et.
al,, Ber,, 35.311? .

3129, (1920), A, Ga5co, G
, Ru'a, E., Menziani.

G, M, Nano, G, Tappi, J, Hete.
rocycle, Chem,, 6°769 (196,
9).

The electrophotographic photoreceptor of the present invention uses a 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 FIG. 2, a laminate of a carrier generating layer 2 containing a carrier generating substance as a main component and a carrier transporting layer 3 containing a carrier transporting substance as a main component on a conductive support 1 is formed. A photosensitive layer 4 is provided. FIG. 1 shows an example in which the carrier transport layer 3 is provided on the carrier generation layer 2, and the second song is an example in which the carrier generation layer 2 is provided on the 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 consisting of a dispersion of
Alternatively, it is installed 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, spraying, etc.
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 resin, polyacrylamide, polyvinyl butyral, 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 material in a binder similar to the above and applying it. In the present invention, the carrier transport material is not particularly limited, but for example, amine. Di-1 derivatives, oxazole derivatives, oxadiazole derivatives, triphenylmethane derivatives, etc. can be used.

Note that the intermediate layer 5 disposed between the conductive support 1 and the photosensitive layer 4 provides a barrier function and an adhesive function, and is made of, for example, casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer. , polyamide (nylon 6, nylon 66, nylon 610, copolymerized nylon, alkoxymethylated nylon, etc.), polyurethane, gelatin, aluminum oxide, etc.

Roughly speaking, the photosensitive layer 4 is made by dispersing a fine particulate carrier generating substance 7 in a layer 6 mainly composed of a carrier transporting substance, and the photosensitive layer 4 is made by dispersing or dissolving the carrier transporting substance in the above-mentioned binder. It can be formed by coating a liquid in which a carrier-generating substance is dispersed.

[Example J of the invention Examples 1 to 10 1 part of 2 parts butyral resin and 10 parts of inbrovir alcohol
10151 listed in the table below is added to the solution dissolved at 0 parts by weight.
Add 5 parts by weight of similar bisazo pigments ground in a ball mill to make molecule 4! Let me, 31! A cervical coating solution was prepared. Then, each coating solution was applied onto a 50 um AI plate using a doku blade so that the film thickness after drying would be 0.3 μm, 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 polyvinylcarbazole are dissolved in 70 parts by weight of monochlorobenzene, and this is placed on the charge generation layer so that the film thickness after drying is 20 μm. A charge transport layer was formed by applying the coating using a Doc Couplade and drying it.

Electrostatic charging test equipment for the 10 types of electrophotographic photoreceptors obtained in this way! (Made by Kawaguchi Electric ■, EP^-81
00 type), statically charged the corona at 16KV, then observed the dark decay for 5 seconds, and set the illuminance to 151u.
The photoelectric properties were evaluated by observing the optical attenuation by x exposure for 5 seconds. The results of the initial charging potential (Vo), sensitivity (El/2), and residual potential (VR) (7) thus measured are shown in Table 3.

Table 3, however, shows the sensitivity as O=good, Δ=fair, and ×=poor.

"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. Further, by using the novel suazo 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 can be widely applied to electrophotographic copiers, laser beam printers, LED printers, CRT printers, or other electrophotographic applications in general.

[Brief explanation of the drawing]

FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5, and FIG. 6 are cross-sectional views showing different specific examples of the layer structure of the electrophotographic photoreceptor according to the present invention, and FIG. FIG. 2 is a diagram showing a reaction formula for synthesizing a dosuazo pigment used in . Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

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, Cp is, ▲There are 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, Cp is, ▲There are 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 each 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. )