JPS6039653A - Electrophotographic photoreceptor - 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 The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor containing a hydrazone compound represented by the following general formula (II) in a layer formed on a conductive support. It is related to.

R.

(In the formula, J is a hydrogen atom, a halogen atom, an alkyl group that may contain a substituent, an alkoxy group, and R3 is a hydrogen atom, an alkyl group that may contain a substituent, an aralkyl group, an aryl group. , R1 and R4 are an alkyl group, an aralkyl group, which may have a substituent, a IJ
.

and n represents Io or an integer of 1. ) In conventional electrophotographic technology, inorganic materials such as selenium, cadmium sulfide, and zinc oxide have been widely used in the photosensitive layer of electrophotographic photoreceptors. A lot of research is being done on using it as a body.

Here, the basic properties required for an electrophotographic photoreceptor are (1) high chargeability due to corona charging in a dark place, and (2) charge due to corona charging obtained there is high in the dark. (3) the charge quickly dissipates when irradiated with light, and (4) there is little residual charge after irradiation with light. Today, organic photoconductive materials The reason why photoconductors using inorganic photoconductors such as selenium, cadmium sulfide, and zinc oxide are being replaced by inorganic photoconductive materials is that photoconductors that use inorganic photoconductors such as selenium, cadmium sulfide, and zinc oxide have poor electrophotographic basics such as chargeability, sensitivity, and residual potential. Although it has advantages in terms of physical characteristics, it also includes various strengths and weaknesses.

Many of the disadvantages arise, for example, from manufacturing difficulties, pollution of raw materials or toxicity in use, and from wholesalers' concerns. In the case of selenium, in addition to the difficult manufacturing conditions for the selenium vapor deposited film, it is weak in mechanical strength and tends to crystallize selenium on the surface of the photoreceptor, and in the case of cadmium sulfide, it is sensitive to temperature and humidity. In the case of zinc oxide, which is sensitive to cadmium compounds and has a pollution problem,
There are problems with dispersion stability when dispersing zinc oxide particles in a resin, and significant performance deterioration due to temperature and humidity.

On the other hand, compared to inorganic photoconductive materials, organic photoconductive materials can often use resin as a binder.
Whether used as a solution or a dispersion, it is easy to manufacture and inexpensive. In addition, the photosensitive layer has excellent flexibility, and it is easy to obtain a photosensitive member that has all kinds of functions depending on the purpose of use of the photosensitive member, and the photosensitive member can be designed in a variety of ways.

Considering these points, recently organic photoconductors? Research and development of electrophotographic photoreceptors using organic photoconductors has become active, and various electrophotographic photoreceptors using organic photoconductors have been proposed, and some of them have been put into practical use industrially.

For example, organic photoconductors such as polyvinylcarbazole are sensitized by adding various biryllium salt dyes (Japanese Patent Publication No. 48-25658), and electron-donating compounds (such as polyvinylcarbazole) and electron-accepting compounds (2. ,4
, 7-dolinitrofluorenone, etc.) to form a charge transfer complex.
Japanese Patent Publication No. 5O-10496), a functionally separated type in which the functions of carrier generation and carrier movement are separated into different substances (4? Publication No. 49-105537),
Photoreceptor made by agglomerating thiapyrylium salt dye (carrier generator) and triphenylmethane type (Japanese Patent Publication No. 48-3
However, although these various proposals have been made, the basic properties required for a photoreceptor as listed above,
A material that satisfies requirements such as mechanical strength, durability, and storage stability has not yet been obtained.

The inventors of the present invention have conducted various studies to address these problems, and have now produced a photoreceptor containing the compound of the present invention.

In the hydrazone compound of the above general formula (Il) according to the present invention, the substituent R is a hydrogen atom, a halogen atom (for example, clonopebrom, etc.), an alkyl group (for example, a methyl group, an ethyl group, a propyl group, etc.) or an alkoxy group (
For example, methoxy group, ethoxy group, propoxy group, etc.), the substituent hole is a hydrogen atom, an alkyl group (f!
For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, etc.), aralky/+4' (9
0 Evahensyl group, β-phenylether group, naphthylmethyl:! The substituent hole and R are
They may be the same or different; alkyl groups (e.g., methyl, ethyl, n-propyl, cyclohexyl, etc.), aralkyl groups (e.g., benzyl,
β-phenylethyl group (he), naphthylmenal group, p-
methylbenzyl group, p-methoxybenzyl group), or (daryl group (e.g. phenyl group, naphthyl group,
') ') represents a 4.2.4-dimenalphenyl group, p-methoxyphenyl group, etc., where n is υ or 1.

These hydrazone compounds represented by the general formula fIl can be produced by a conventional method. ilI! By adding it as a medium and heating it, the hydrazonated @ substance f
Obtain Il.

Representative outside @ Sei 1ri 11 meeting is recorded.

Synthesis ν1 Exemplary Compound (2) Piveronal 3L and 1,1-diphenylhydrazine”
Add 4.49 g of oxalate to 2.9 g of potassium acetate, and add ethanol to 91 g (heat reflux on the mountain surface). , precipitated 'f71'C
Pump, wash with water, and use ethyl acetate! When Il Tan Yu crystal, I get 4.517 points of white crystal with 1 unique point of 137 degrees.

By such a method, uninvented compounds 2 can be obtained, representative examples of which are shown, but the present invention is not limited thereto.

The uninvented electrophotographic photoreceptor has all the excellent properties by containing one or more of the above-mentioned compounds in the photosensitive layer. Various methods are known for the form of a book used as a body. For example, a photoreceptor is prepared by dissolving or dispersing the present hydrazone compound and a sensitizing dye in a binder, with the addition of a chemical sensitizer or an electron-withdrawing compound if necessary, on a conductive support. Alternatively, in the form of a laminated structure consisting of a carrier generation layer with extremely high charge carrier generation efficiency and a carrier transfer layer, the carrier generation layer is provided on a conductive support mainly with a sensitizing dye or M family. On top of that, there are photoreceptors in which a nonhydrazone compound, optionally a chemical sensitizer or an electron-withdrawing compound, is dissolved or dispersed in a binder as a carrier transport layer. It can be applied to any @ stand and can be used for machining! 1 onto a support such as a plastic film.
A film is formed by applying a #; agent together with a compatible film-forming binder. In this case, for the purpose of further improving the sensitivity or the mechanical strength, adhesion, and durability of the photoreceptor, substances that impart plasticity to the sensitizer or polymerizable film-forming binder as described below may be used. It is also possible to add t-.

As the polymerizable film-forming binder, the following may be used.

Polystyrene resin, styrene-butadiene copolymer resin, polyvinyl acetal resin, diallyl phthalate resin, silicone resin, polysulfone resin, polycarbonate resin, acrylic resin, methacrylic resin, vinyl acetate resin, acetic acid-bicrotonic acid copolymer resin, polyphenylene oxide resin , polyester resin, alkyd resin, polyarylate resin, styrene-maleic anhydride co-paged composite resin, styrene-maleic anhydride Hafestel resin,
These include phenolic resin, butyral resin, poval resin, etc., and these can be used alone or together! As the 11@ body polymer, it can be used alone or in combination of two or more. or,
Are these binding agents Ariiso Hikaru? JjliJi for the recruitment body
It is suitable to add at a ratio of 0.2 to 20 times, preferably in a range of 0.5 to 5 times.

If the magnification is less than 0.5 times, there is a drawback that the shoulder sightings are deposited between the surfaces of the photoreceptors, and if the magnification is more than 5 times, the sensitivity will be seriously degraded.

In this case, the ridges used to hold the lees base agent are:
If the formed photosensitive layer is not flexible or brittle, or if it is bent or
There are some types of pressure-sensitive materials that lack durability, and in order to improve these properties, it is necessary to cool the substance that imparts plasticity. These #/Ili include phthalate esters, phosphorus esters (such as diallyl phthalate, cyphthyl phthalate, and tritalesyl phosphate), epoxidized soybean oil, nitrile comb, and hydrogenated hydrocarbons. Roku, Aririnoshiruka, and these 9 Noga's 1-stories use for the knotting agents are 0 in Teishikari.
．． If 1 to 20% is used, the electrophotographic properties will be adversely affected.

Next, the sensitizing dyes applied to the photosensitive layer include triphenylmethane-based agents such as 71 f olet, crystal violet, ethyl violet, night blue, and Victoria blue, and erythrosine rhodamine B10- Zansen dyes such as Damin 3B and Acridine Red B; acridine dyes such as Acridine Orange 2G, Acridine Orange 2G, and 7 Labeosin; thiazine dyes such as Methylene Blue, Methylene Green, and Methyl Violet; and Kabri Blue. , occipsin dyes such as Meltlab, other cyanine dyes, styryl dyes, biryllium salts, and thiapyrylium salts.

Examples of photoconductive pigments that are present in the photosensitive layer and generate charge carriers with high efficiency by being quenched by light absorption include phthalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine, beryl imide, and perylenic anhydride. There are azo pigments such as perylene pigments, monoazo pigments, bisazo pigments, and trisazo pigments, as well as quinacridone pigments and anthraquinone pigments.

Furthermore, as inorganic photoconductive substances, selenium and selenium-
In addition to sensitizers (spectral sensitizers) that have a temperature of 0 or higher, such as tellurium base metal, cadmium sulfide, and zinc oxide, sensitizers (chemical sensitizers) may be added to further increase sensitivity. It is possible. Chemical sensitizers include, for example, p-talomitsuenol, m-talomitsuenol, p-nitrophenol, 4-gloro-m-cresol, p-chloropenzoylacetanilide, N,N-diethylbarbituric acid,
N,N'-diethylthiobarbital acid, 3-(β~oxyethyl)-2-phenylimino-thiazolidone, malon 1-wave dianilide, 3°3',5,5'-tetrachloromalonic acid dianilide, α - Naphtonobenzoic acid, p-nitrobenzoic acid, etc.

Further, it is also possible to add an electron-withdrawing compound which acts as a sensitizer by combining with the hydrazone compound of the present invention to form a total cargo transfer complex and further increasing the total sensitizing effect.

Examples of this substance include 1-chloroanthraconone, 1
-Nitroanthraquinone, 2,3-di10-naphthoquinone, 3,31-dinitrobenzophenone, 4-nitrobenzalmalononitrile, phthalic anhydride, 3-(α-cyano-p-nitrobenzal)phthalide, 21417-t! Examples include j-nitrofluorenone, 1-mef-4-nitrofluorenone, 2,7-sinitro-3,6-dimethylfluorenone, and the like.

In addition, antioxidants, ultraviolet absorbers, and the like may be added to the photoreceptor as necessary.

The hydrazone compound of the present invention can be used depending on the form of the photoreceptor.
Dissolve or disperse in a suitable solvent together with the various additive substances mentioned above, and apply the coating solution on the conductive text mentioned above,
Dry to produce a photoreceptor.

As a coating solvent, most organic solvents can be used. Aromatic hydrocarbons such as benzene, toluene, xylene, and monochlorobenzene, chloroform, dichloroethane,
) Chlorinated hydrocarbons such as IJl ethylene, ethers such as dioxane and tetrahydrofuran, and solvents such as ethyl acetate, butyl acetate, methyl chloride acetate, etc. alone or in combination of two or more solvents, or as necessary. Alcohols, acetonitrile, N,
A solvent such as N-dimethylformamide or methyl ethyl ketone may be further added.

Next, the invention will be explained in more detail with reference to Examples, but the present invention is not limited thereto.

Example 1 Dichloroethane was added to the pigments shown below and dispersed using a Dyno Mill disperser to prepare a coating liquid. This dispersion was applied using a doctor onto a conductive support made of a polyester film laminated with aluminum foil. A charge generation layer having a dry thickness of about 0.1 μm was formed.

Next, 1 part by weight of the compound of the present invention shown below and 1.2 parts by weight of polyarylate resin were dissolved in 10 parts by weight of monochlorobenzene, and this solution was placed on the charge generation layer prepared above using a doctor. A charge transfer layer with a dry film thickness of approximately 17μ? Formed.

The photoreceptor obtained in this way? The electrophotographic performance was evaluated using an electrostatic recording paper tester (Kawaguchi Electric, Model 8F-428). As a result, when corona charging was measured at 16 KV, the dark decay rate after 10 seconds with respect to the initial charge amount was 93%, and the half-decrease exposure amount to white light (10 lux) was 12.5 lux Φ seconds. there were.

Example 2 Using an anodized aluminum plate (thickness 100μ) as a support, 1 part by weight of the pigment used in Example 1 as a charge generating agent and a styrene-maleic anhydride copolymer resin (acid value 15
0) in a mixed solvent of toluene and butyl acetate (1:1).
The coating liquid was dispersed using a Dyno Mill dispersion machine to give a total weight percentage of 0.2% by weight, and then applied using an 8-doctor to form a charge generation layer with a dry film thickness of 0.2μ. −
A solution of 1.5 parts by weight of an acrylic acid copolymer resin (acid value 180) dissolved in total monochlorobenzene to a concentration of 10% was prepared and coated on the charge generation layer.
The dry film thickness was approximately 6μ.

The exposure amount for half the sensitivity of this photoreceptor was 9 lux·sec.

Further, in order to check the effectiveness of this photosensitive plate as a plate-making master, test chart image exposure was carried out using an electrophotographic plate making machine BP-11 manufactured by Mitsubishi Paper Mills, and after toner development, etching was performed with an organic alkaline solvent. The image reproducibility as a plate making master is good, and the performance as a master is excellent. It turned out that I have it.

Example 3゜ As a charge generating agent, ε-type copper phthalocyanine (manufactured by Toyo Ink) pigment and acrylic acid methyl ester-acrylic acid copolymer resin (acid value 130) were blended at a pigment/binder ratio L/3 weight ratio. This was mixed in a toluene-butanol mixed solvent (1:1) at a concentration of 2.5% using a dispersion machine, and this dispersion was applied to an aluminum plate that was grained so that the dry film thickness was 0.4μ. (120μ) was coated onto a support using an S-doctor. 1 part by weight of the exemplary compound (3) of the present invention as a charge transfer substance and styrene-maleic anhydride 1-phester resin (
Acid value 160) 1 part by weight mixture Total butyl acetate 10% by weight
A solution containing iC was prepared and coated on the above charge generation layer to obtain a photoreceptor having a charge transfer layer with a dry film thickness of approximately 6μ. I got it in 5 lux seconds.

As in Example 2, after exposure, development, and etching steps were performed using a plate-making machine, a gumming treatment was performed to obtain a printing plate master. When this master was printed on a printing press, over 10,000 copies of printed images with good reproducibility were obtained.

Claims (1)

[Scope of Claims] (11) An electrophotographic photoreceptor characterized by having a layer containing a compound represented by the following general formula (11) on a conductive support. , represents a halogen atom, an alkyl group that may have a substituent, or an alkoxy group; ・R represents a hydrogen atom, an alkyl group that may have a substituent, an aralkyl group, or an aryl group; , represents an optionally substituted alkyl group, aralkyl group, or aryl group, and n represents an integer of 0 or 1.)