JPS59232351A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a photosensitive body which can be easily manufactured and is suitable for reiterative use by incorporating a specific disazo compd. into a photosensitive layer provided to said photosensitive body. CONSTITUTION:An electric charge generating layer 22 and an electric charge transport layer 33 are provided on a conductive base 11 by which a photosensitive body 44 is formed. The disazo compd. expressed by the formula is incorporated into the layer 44. A metallic sheet consisting of aluminum or the like, a plastic film provided with a thin layer of aluminum, tin oxide, palladium, etc. and paper, etc. coated thereon with a conductive material are used for the base 11. The layer 22 is formed by coating a liquid prepd. by dispersing the disazo compd. in the form of fine particles into a solvent on the base 11. The thickness of the layer 22 is made preferably to 0.01-5mum and the ratio of the disazo compd. in the layer 22 to 10-100wt%. In the formula, R1 and R2 denote hydrogen, lower alkyl group, aralkyl group, arom. group and heterocyclic group.

Description

[Detailed description of the invention] Technical field The present invention relates to a photoreceptor for electrophotography.

Prior Art Conventionally, inorganic photoconductors for photographic applications have been produced, such as inorganic ones using selenium and its alloys, or photoconductors made by dispersing dye-sensitized zinc oxide in a binder resin.
In addition, for organic substances, 2,4.7-)linitro9
-Fluorenone (hereinafter referred to as TNF)
A typical example is one using a charge transfer wJ complex with -pinylcarnozole (hereinafter referred to as PVK).

However, while these photoreceptors have many advantages, they also have various disadvantages.

For example, the currently used selenium photoreceptors have difficult manufacturing conditions, are expensive to manufacture, are difficult to process into belts due to their lack of flexibility, and are difficult to process using heat or machinery.

It is sensitive to physical shock, so care must be taken when handling it.

Zinc oxide photoreceptors are low in cost because they can be manufactured by applying inexpensive zinc oxide to a support, but they generally have low sensitivity and poor surface smoothness, hardness, tensile strength, and abrasion resistance. There are various drawbacks such as durability, etc., and there are many problems such as durability as a photoreceptor for plain paper copying machines that are usually used repeatedly. Additionally, photoreceptors using a charge transfer complex of % TNF and PVK have low sensitivity and are unsuitable as photoreceptors for high-speed copying machines. Research is progressing, and various organic photoreceptors have been proposed. Among others.

A layer containing a substance that generates charge carriers when photosonically irradiated (hereinafter referred to as a charge-generating substance) (hereinafter referred to as a charge-generating layer)
Conventionally, a laminated photoreceptor is composed of a charge generation layer that receives and transports generated charge carriers (hereinafter referred to as a charge transport material) and a layer that serves as a charge carrier (hereinafter referred to as a charge transport layer). Compared to other organic photoreceptors, it is generally more sensitive and has more stable chargeability, so it has attracted attention as a photoreceptor for plain paper copiers, and some of them are in practical use. be.

As this kind of conventional laminated photoreceptor.

(1) A thin layer of a perylene derivative deposited in full vacuum as a charge generation layer and an oxadiazole derivative as a charge transport layer (U.S. Pat. No. 88F 1882) A thin layer formed by applying an Aban solution and a hydrazone compound used as the S charge transport layer (Japanese Patent Publication No. 55-42
(see Publication No. 880), etc. are known.

However, it is true that conventional laminated photoreceptors of this type have many advantages, but also have various disadvantages.

The photoreceptor using the perylene derivative and oxadiazole derivative shown in (1) is expensive to manufacture because it is formed by vacuum evaporation using a charge-generating process.

Further, even if there is no practical problem, there are problems such as insufficient sensitivity as a photoreceptor for a high-speed copying machine.

The photoreceptor using chlordiane blue and a hydrazone compound shown in (2) can be used as a coating solvent for forming a charge generation layer. Generally, it is necessary to use an organic amine (eg, ethylene cyano) which is difficult to handle, which has disadvantages in producing photoreceptors.

Purpose The inventor of the present invention has made extensive studies in view of one or more points with the aim of developing a photoreceptor that is easy to manufacture and suitable for repeated use.

The present invention was completed by discovering that a certain specific disazo compound can achieve the above object.

Structure The electrophotographic photoreceptor of the present invention is an electrophotographic photoreceptor in which a photosensitive layer is provided on a conductive support. Alkyl group.

Substituted or unsubstituted aralkyl group, substituted or unsubstituted aromatic group. WL represents a substituted or unsubstituted heterocyclic group, and R1 and R1 may be the same or different. ! ftaR
1 and R1 may jointly form a base. ] It is characterized by containing a disazo compound represented by the following.

Among these photoreceptors, the photoreceptor I@ is constructed by laminating a charge generation layer and a charge transport layer. The above general formula (1) is present in the load generation layer.
A laminated type photoreceptor containing a disazo compound is preferred.

Here, the lower alkyl group in the general formula (Ij) includes a methyl group, ethyl group, propyl group, etc., the aralkyl group includes a benzyl group, phenethyl group, etc., and the aromatic group includes a phenyl group, naphthyl group, anthryl group, etc. Examples of the heterocyclic group include a chenyl group, a furyl group, a pyridyl group, and a carnosezolyl group. Examples of the ring formed by kRl and R8 include a hexylidene ring, a pentylidene ring, and a benzopentylidene ring. , dipenzopentylidene ring, etc. Aralkyl groups, aromatic groups, heterocyclic groups, or substituents on the ring formed by R1 and R1 include lower alkyl groups, lower alkoxy groups, halogen atoms, cyano groups, nido t = group, lower dialkyl ε) group, and the like.

The following two aspects of the present invention will be explained in more detail.

First, specific examples of the disazo compound used in the present invention are as follows.

(Left below) The above disazo compounds are disclosed in JP-A-57-90057, JP-A-57-90056, or JP-A-56.
The diazonium salt described in JP-A-86145 and the corresponding 2-hydroxy-8-naphthoic acid hydrazide,
It can be easily produced by carrying out a coupling reaction in a suitable organic solvent such as N,N-dimethylformamide (DMFJ) with a base.

Although the charge transporting material used in the present invention is not specified, typical examples thereof are as follows.

[RIo is an alkyl group such as a methyl group or an ethyl group, 2-
Chlorethyl group % Substituted alkyl group such as 2-hydroxyethyl group, R11 is a methyl group, an alkyl group such as ethyl group, an aralkyl group such as benzyl group, aryl group such as phenyl group H1m is a hydrogen atom, chlorine, bromine, etc. Alkyl groups such as halogen atoms, methyl groups, ethyl groups, propyl groups, butyl groups.

Methoxy group, ethoxy group, propoxy group.

It represents an alkoxy group such as a butoxy group, a dialkylamino group, or a nitro group. [Ar' is a naphthyl group, an anthryl group, a styryl group, or a substituent thereof H1j is a methyl group.

It represents an alkyl group such as an ethyl group, an aralkyl group such as a benzyl group, and an aral group such as a phenyl group. Substituents for naphthyl, anthryl, and styryl groups.

Examples include alkyl groups such as methyl and ethyl groups, alkoxy groups such as methoxy and ethoxy groups, dimethyl groups, and dialkylamino groups such as diethylamino groups. ] [RμB1m or R'? [Hydrogen atom, methyl group.

Alkyl groups such as ethyl and propyl groups.

Represents an alkoxy group such as a methoxy group, ethoxy group, or propoxy group, a rogene atom (such as chlorine or bromine), a nitro group, or a hydroxyl group.

R16 is a hydrogen atom, an alkyl group such as a methyl group, ethyl group, or propyl group, or a methoxy group.

Alkoxy groups such as ethoxy and propoxy groups, dialkylamino groups such as dimethylamino and diethylamino groups, dialkylamino groups such as dibenzylamino, diarylamino groups such as diphenylamino, and halogen atoms such as chlorine and bromine. , nitro group or hydroxyl group, R16
represents an alkyl group such as a methyl group or an ethyl group, an aralkyl group such as a benzyl group, or an aryl group such as a phenyl group. ] [R', R"O, R11t 7'c# R"u hydrogen, alkyl group such as methyl group, ethyl group, f-robyl group, alkoxy group such as methoxy group, ethoxy group, soropoxy group, Dimethyl ε) group, dialkylamino groups such as diethylamino group, and halogen atoms such as chlorine and bromine.

Represents a nitro group or a hydroxyl group. ] (R1J is an alkyl group having 1 to 11 carbon atoms, titm or an unsubstituted phenyl group, a substituted or unsubstituted heterocyclic group, and R14 or Hlli is a hydrogen atom.

B represents an alkyl group such as a methyl group, ethyl group, 'j'ropyl group, or butyl group, a chloro-substituted alkyl group, a hydroxy-substituted alkyl group, or a substituted or unsubstituted aralkyl group.
u and R21 may be bonded to each other to form a nitrogen-containing heterocycle. R16 or R17 is a hydrogen atom, a methyl group,
It represents an alkyl group such as an ethyl group, a propyl group, a butyl group, an alkoxy group such as a methoxy group or an ethoxy group, or a halogen atom such as chlorine or bromine. The heterocyclic group for R13 is a pyridyl group, a furyl group, a chenyl group, an indolyl group,
Examples of substituents on the phenyl group or heterocyclic group of 6R18 include pyrrolyl group, quinolyl group, carbazolyl group, etc., alkyl groups such as methyl group and ethyl group, and alkoxy groups such as methoxy group and ethoxy group. . Examples of the aralkyl group at the R14 or R1 position include a benzyl group, and examples of substituents on the aralkyl group include halogen atoms such as chlorine and bromine, alkyl groups such as methyl and ethyl groups, and nitro groups. A morpholine ring is an example of a heterocycle formed by bonding eR'' and RIS- to each other.] [Rffill is a halogen such as a hydrogen atom, chlorine, or bromine
1 atom, Rlg is a limescale atom, a halogen atom such as chlorine or bromine, an alkyl group such as a methyl group or an ethyl group, an alkoxy group such as a methoxy group or an ethoxy group, a dimethylamino group, a diethyla ε) group, a dimethylamino group, Nato dialkylamino group, dibenzylamino group.

A dialkylamino group such as a chloro-substituted dibenzylamino group, a nitro group, a cyano group, or a halokene atom such as an atom, an alkyl group such as a methyl group or an ethyl group 'fj: represents. ]CR11 is a hydrogen atom, chlorine,
Halogen atoms such as bromine, alkyl groups such as methyl, ethyl and butyl groups, methoxy and ethoxy groups.

7° alkoxy group such as cytoxy group or cyano group, R company or lζ3s is a hydrogen atom, a methyl group.

Alkyl groups such as ethyl group and butyl group, substituted alkyl groups such as 2-chloroethyl group and 2-hydroxyethyl group,
Alternatively, R34 or R311 is a substituted or unsubstituted benzyl group, a hydrogen atom, or a halogen atom such as chlorine or bromine.

Alkyl groups such as methyl group, ethyl group, butyl group, alkoxy groups such as methoxy group, ethoxy group, butoxy group,
Represents a dialkylamino group such as a dimethylamino group or a dimethylamino group. Examples of substituents on the benzyl group of Bam or Has include alkyl groups such as methyl and ethyl groups, alkoxy groups such as methoxy and ethoxy groups, and nitro groups. ] (Ar' represents an N-alkylcarnozolyl group, and examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, etc.) (RM, Bl?, B main hydrogen atom, chlorine, bromine, etc. HAS is a halogen atom, an alkyl group such as a methyl group or an ethyl group, an alkoxy group such as a methoxy group or an ethoxy group, a nitro group or an aba) group. Alkyl group, methoxy group, alkoxy group such as ethoxy group, dialkylamino group such as dimethylano group, dietelino group, dibutyl ryobano group, dibenzylamino group, chloro-substituted dibenzyl-ryomino group h, methyl-substituted dipendyla ε
a substituted or unsubstituted dialkylamino group, N-methyl-N-benzyl aba/'M-& any N-alkyl-N-aralkyl group, Cal? Oxy group or its ester, amino group, hydroxy group, cyano group.

Represents an acetylbano group. (B11 represents an N-diylcarnozolyl group, pyridyl group, chenyl group, indolyl group, furyl group, or a substituted or unsubstituted naphthyl group, styryl group or anthryl group. Naphthyl group, styryl group.

Examples of substituents on the anthryl group include alkyl groups such as methyl and ethyl groups, alkoxy groups such as methoxy and ethoxy groups, and dialkylamino groups such as dimethyl(epsilon) and dimethylamino groups. ](R”#R
” is a hydrogen atom, methyl group, or ethyl group.

Alkyl groups such as butyl groups, methoxy groups.

Represents an alkoxy group such as an etoyac group or a cytoxy group, a halogen atom such as halogen or bromine, a dialkylamino group such as a dimethyl ai) group or a dimethylamino group, and nl is 0.
Or 1? +- represents. ] [84m, 'R44 is a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, an alkyl group such as a methoxy group or an ethoxy group, or a halogen atom such as chlorine h R"s R"
B Methyl group, ethyl group.

Alkyl groups such as proyl group and butyl group.

Substituted or unsubstituted aralkyl group, substituted or unsubstituted aryl group IL4? Is it a hydrated atom or a substituted or unsubstituted phenyl group? As the aralkyl group of l-Tatsuwasu, H411, g4@, for example, a benzyl group is also used.
An example of the group is a linear phenyl group. In addition, substituents on aralkyl or aryl groups include alkyl groups such as methyl, ethyl and butyl groups, methoxy groups,
Examples include an alkoxy group such as an ethoxy group, a halogen atom such as chlorine, a dialkyl ester group such as a dimethyl ester group, and a diethylamino group. [R48 and R411 are an alkyl group such as a methyl group or an ethyl group, or a substituted or unsubstituted phenyl group.

Represents substituted or unsubstituted benzyl foundation.

Substituents include alkyl groups such as methyl and ethyl groups,
Examples include alkoxy groups such as methoxy and ethoxy groups. ] [R”, R” hJJa R'a, R” (!:
The same Da k-H Wa f. ] (EL!+1 is a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, or a substituted or unsubstituted phenyl group, R2 is 0 or 1IIJ+,
h is a 9-anthryl group or substituted or unsubstituted N-
Represents an alkylcar, .ζzolyl group.

Here, or a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, or a substituted amino group (n
” *Nishiki represents an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a substituted or unsubstituted 72 alkyl group such as a benzyl group, a substituted or unsubstituted aryl group such as a phenyl group, and R″ and P″′
r″FAr (may be formed), 1m is 0.1
．． Represents an integer of 2 or 8, and if 1m is 2 or more, R1
8 may be the same group or different groups. R14 or R1
Examples of substituents on the aralkyl group or aryl group in 1I' include alkyl groups such as methyl, ethyl, propyl, and butyl groups, methoxy groups, and ethoxy groups; Hao
)y' y Jiff.

Examples include a dimethylamino group, a diethyl group, and a dialkyl group. ] Roughly speaking, specific examples of these transportable substances are as follows.

Compound 1 Structural formula) % formula %) Compound layer structure Formula CtH,C
7n c, H, o H C, H40H Compound layer structure 2〇, H.

Compound layer structure Formula compound layer
Structural formula C1l.

Compound/I6 structure formula compound shoulder structure formula compound rot
Structural formula compound CM.

Compound Genus Structure Formula Compound Layer
Structural formula compound layer
Structural formula Compound structure
Structural compound structure
In addition to the above-mentioned exemplified compounds, polymeric substances include poly-N-vinylcarbazole, halogenated poly-N-vinylcarbazole, polyvinylpyrene, or brompyrene-formaldehyde condensation resin, Condensation resins such as N-etheno-1-cal-2-formfuldehyde condensation tree.

Oxazole derivatives are also used as low molecular weight substances.

Any of the known charge transport materials such as oxadiazole derivatives, nitro derivatives of fluorenone, etc. are effective.

FIG. 1 is an enlarged sectional view of an electrophotographic photoreceptor showing an embodiment of the present invention. This photoreceptor generates charges 622. on the conductive support 11. A load carrying layer 88 is provided and the photosensitive rVI44
is configured to form a

The conductive support used in the present invention includes:

Aluminum, nickel, chrome plated metal plates,
Metal drum or gold, 1 soul foil, and thin N such as aluminum sW tin, oxide indium, chromium, haladium, etc.
A glass film provided with a conductive substance or a paper or plastic film coated with or impregnated with a conductive substance are used.

The charge generation layer 22 is made of a liquid in which a specific disazo compound represented by the general formula CI) shown above is made into fine particles by a means such as a Zeel mill, and dispersed in an appropriate solvent, or a liquid containing the necessary V(
Accordingly, a dispersion in which a binder, so-called fat, is dissolved is coated on the conductive support 11, and if necessary, the entire surface is finished by a method such as multiple puffing*! 'R thickness has been adjusted.

The thickness of this charge generation layer 22 is 0.01 to 5 μm.

Preferably 0.05 to 2 μm''C, !Charge generation layer 2
The proportion of the disazo compound in 2 is 10 to 100%, preferably 8O-951iii96. If the film thickness of the a'#L charge-generating layer 22 is less than 0.01 μm, the sensitive layer is poor.
If it is more than μm, the potential is poorly maintained. Further, if the proportion of the disazo pigment in the charge generation layer is less than 10 times 1s, the sensitivity is low.

The charge transport layer 88 is formed by coating the charge generating layer with a solution in which the charge transport materials described above and a binder resin are dissolved in a suitable solvent such as tetrahydrofuran.

Here, the ratio of the charge transport substance contained in the charge transport layer 88 is 10 to 80% by weight, preferably 25 to 75% by weight, and the warped film thickness is 2 to 100 μm, preferably 5 to 40 μm.
It is μm.

The proportion of the charge transport substance contained in the charge transport layer 88 is lO
Sensitivity is poor under a heavy plate (under 80 weight or above), the film becomes brittle, crystals precipitate, and the charge transport layer 88 becomes cloudy, which is undesirable.

Also, *if the thickness of the load transport layer 88 is 2 μm or less, the potential is not maintained well (and if it is 100 μm or more, the residual potential becomes high).

The binder resin for the charge generating FfIi22 used here includes polyester resin, butyral resin, ethyl cellulose resin, epoxy resin, acrylic resin, and vinylidene chloride resin.

Examples include polystyrene, polyzotadie, and copolymers containing at least one of these monomers,
They may be used alone or in a mixture of two or more.

! /-1″11i″″JUOme*! , 1mDW h
L″′C is polycarbonate resin, polyester resin, polystyrene, polyurethane resin, epoxy resin,
Examples include acrylic resins, silicone resins, and copolymers containing at least one of these monomers, which may be used alone or in a mixture of two or more.

Additionally, various additives may be added to the charge transport layer 88 for any purpose such as improving flexibility or improving durability. Examples of additives used for this purpose include halogenated/ξ rough-in, dialkyl phthalate, silicone oil, etc. In the photoreceptor of the present invention, if necessary, Barrier layer 1 between generation layer 22! It is also possible to provide an intermediate layer between the charge generating layer 1-22 and the charge transporting layer 88, and an opaco)H between the charge transporting layer 1ζ388. It can also be used as a dispersed photoreceptor by dispersing it as fine particles in a binder resin (a charge transporting substance may be added if necessary).

Effects The structure of the present invention is as described above, and as is clear from the examples described below (1) the electrophotographic photoreceptor of the present invention is easy to cause defects;
Moreover, it has excellent properties such as stable characteristics even when the photoreceptor is used repeatedly.

? EXAMPLES The present invention will be explained in detail with reference to Examples, but the embodiments of the present invention are not limited thereto.

Example! A total of 76 parts by weight of disazo compound A11-82.

Polyester resin (Byron 200, manufactured by Toyobo Co., Ltd.) tetrahydrofuran ig, (solid content 6% 2%) 12
60 heavy negative part 1 and tetrahydrone run 8700 Eibu! + pulverized and mixed in a tile, resulting in a dispersion t
It was coated onto the aluminum ε surface of an fc polyester base (conductive support) on which aluminum was vapor-deposited using a doctor blade, and air-dried to form a charge generation layer with a thickness of approximately 1 μm. On the other hand, charge transport material 2-29'? : 2M solution, polycarbonate reagent (1800 in Panlite, 2 parts by weight manufactured by Yujin Co., Ltd. and 16 parts by weight of tetrahydrofuran) After mixing all of the needle part, mix all of this on the charge generation layer. Apply with a doctor blade and heat at 80℃ for 2 minutes, then 1
A charge transport layer having a thickness of about 20 μm was formed by drying at 00° C. for 5 minutes, thereby producing a laminated photoreceptor 761 shown in FIG.

As a substitute for the disazo compound 1-82 and charge transport substance 2-29 used in Example 1.

Photoreceptor layers 2 to 80 were prepared in the same manner as in Example 1 except that the disazo compound and charge transport substance shown in Table 1 below were used.
It was created.

These photoreceptor layers 1 to 80 were tested using an electrostatic copying paper tester (manufactured by Yoguchi Electric Co., Ltd./7i).

5P42B type), -6KV (D colo f radiation 'g'
i After being charged negatively for 20 seconds.

Leave it in a dark place for 20 seconds, then check the surface potential Vpo.
After measurement, the surface was irradiated with light using a tungsten lamp at an illuminance of 4.5 lux, and the surface potential was Vp.

The time until H (seconds Jt) is calculated, and the exposure amount Ei (looks ψ seconds Jt-calculated.The results are shown in Table 1.Table 1) Furthermore, five photoreceptors of the present invention, m1h7g61i and A2
It was attached to a copying machine Ricobee P-500 manufactured by Noriko Co., Ltd. 1'eC, and the image output was repeated 000 times. As a result, clear images were obtained from all photoreceptors.

It can be seen that the photoreceptor of the present invention has extremely excellent durability.

[Brief explanation of the drawing]

FIG. 1 is an enlarged cross-section i11] showing an example of the structure of the electrophotographic photoreceptor of the present invention.

Claims (1)

[Claims] 1. In an electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, the photosensitive layer has the following general formula (■) [wherein R1 and R8 are hydrogen or a lower alkyl group] . The substituted or unsubstituted aralkyl group, the R-substituted or unsubstituted aromatic group, the tie-substituted or unsubstituted heterocyclic group R, and R2 may be the same or different. Further, turtle and R may jointly form a ring. ] An electrophotographic photoreceptor characterized by containing a disazo compound represented by the following.