JPS59232350A - 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 layer 44 is formed. The disazo compd. expressed by the formula is incorporated into the layer 44. A metallic sheet, metallic drum or metallic foil consisting of aluminum or the like or paper coated or impregnated with a conductive material is used for 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, aromatic group and heterocyclic group.

Description

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

Prior Art Conventionally, there have been inorganic photoreceptors for electrophotography, such as those using selenium and its alloys, or photoreceptors in which dye-sensitized zinc oxide is dispersed in a binder resin.
In addition, organic substances include 2,4.7-)dinitro-9
A typical example is one using a charge transfer complex of -fluorenone (hereinafter referred to as TNF) and poly-N-vinyl carbacy/I/ (hereinafter referred to as PVK). However, while these photoreceptors have many advantages, they also have various disadvantages.

For example, the currently widely used selenium photoreceptor has difficult manufacturing conditions and high manufacturing costs, is difficult to process into a belt due to its lack of flexibility, and is sensitive to heat and mechanical shock. Therefore, handle with care.

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, abrasion resistance, etc. It has mechanical drawbacks, and as a photoreceptor for plain paper copying machines, which is normally used repeatedly, there are many problems in terms of durability. Furthermore, the photoreceptor using a charge transfer complex of TNF and PVK has low sensitivity (and is unsuitable as a photoreceptor for high-speed copying machines).

In recent years, extensive research has been carried out to eliminate the drawbacks of these photoreceptors, and in particular, various organic photoreceptors have been proposed. Among them, charge carriers when irradiated with light? A layer containing a charge generating substance (hereinafter referred to as a charge generation substance) (hereinafter referred to as a charge generation layer), and a substance that receives and transports charge carriers generated by the charge generation layer (hereinafter referred to as a charge transport substance) (hereinafter referred to as charge transport layer)
Laminated type photoreceptors consisting of these materials are attracting attention as photoreceptors for plain paper copiers because they generally have higher sensitivity and stable charging properties than conventional organic photoreceptors. Some of them are in practical use.

Conventional laminated photoreceptors of this type include (1) one in which a thin layer of perylene conductor is vacuum-deposited as a charge generation layer and an oxadiazole derivative is used as a charge transport layer (
(See U.S. Pat. No. 3,871,882), (2) A thin layer χ formed by coating an organic amine solution of chlordian blue as a charge generation layer, and a hydrazone compound as a charge transport layer (Japanese Patent Publication No. 55-42
(see Publication No. 380), 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 conductor and oxadiazole derivative shown above has a high manufacturing cost because its charge generation layer is formed by vacuum deposition.

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

The photoconductor using chlordiane blue and a hydrazone compound shown in (2) generally requires the use of an organic amine (e.g. ethylenediamine) as a coating solvent to form the charge generation layer. There are some flaws in the creation.

Purpose In view of one or more points, the present inventor has conducted intensive studies to develop a photoreceptor that can be easily produced and is suitable for repeated use, and has found that a certain disazo compound achieves the above purpose. The present invention was completed based on the following findings.

(J(1) The electrophotographic photoreceptor of the present invention is an electrophotographic photoreceptor in which a photosensitive layer is provided on a conductive support, in which the photosensitive layer has the following general formula (1) [wherein R8 and R1 are Represents hydrogen, a lower alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic group, a substituted or unsubstituted heterocyclic group, and R8 and R8 may be the same or different. .

Further, R1 and R2 may jointly form a ring.

] It is characterized by containing a disazo compound represented by these.

Among these photoreceptors, a laminated photoreceptor is preferred, in which the photosensitive layer is constructed by laminating a charge generation layer and a charge transport layer, and the charge generation layer contains a disazo compound of the general formula 0).

Here, examples of lower alkyl groups in general formula (1) include methyl group, ethyl group, propyl group, etc., examples of acylkyl groups include benzyl group, phenethyl group, and examples of aromatic groups include phenyl group, naphthyl group, anthryl group, etc. Examples of the heterocyclic group include a chenyl group, a furyl group, a pyridyl group, and a carbazolyl group. Examples of the ring formed by R1 and R2 include a hexylidene ring, a henchylidene ring, and a pentyl group. Examples include sohentylidene ring and dipenzopentylidene ring. Examples of substituents on the aralkyl group, aromatic group, heterocyclic group, or the ring formed by R3 and R3 include lower alkyl groups, lower alkoxy groups, halogen atoms, cyano groups, nitro groups, and lower dialkylamino groups. .

The present invention will be explained in more detail below.

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

The above-mentioned disazo compounds are disclosed in JP-A-56-2353, JP-A-56-145262, or JP-A-56-56.
The diazonium salt described in JP-A-2352 and the corresponding 2-hydroxy-3-su7toic acid hydrazide moe.

It can be easily produced by carrying out a coupling reaction with a base in a suitable organic solvent, such as N,N-dimethylformamide (DMF).

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

R” (RIO is an alkyl group such as a methyl group or an ethyl group!, 2-
/ Substituted alkyl group such as lorethyl group and 2-hydroxyethyl group Bll is an alkyl group such as methyl group or ethyl group, heptaralkyl group such as penzyl group, aryl group such as phenyl group, R1! is a hydrogen atom, a halogen atom such as chlorine or bromine, an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, an alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a dialkylamino group or a nitro group represents.

[Ar' represents a naphthyl group, an anthryl group, a styryl group, or a substituted product thereof; R18 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. Examples of substituents on naphthyl, anthryl, and styryl groups include alkyl groups such as methyl and ethyl groups, alkoxy groups such as methoxy and ethoxy groups, and dialkylamino groups such as dimethylamine and diethylamino groups. It will be done. ] -114, R111 or BN is a hydrogen atom, a methyl group,
] It represents an alkyl group such as an ethyl group or a propyl group, an alkoxy group such as a methoxy group, an ethoxy group, or a propoxy group, a norogen atom such as chlorine or bromine, a nitro group or a hydroxyl group, and R16 is a hydrogen atom, a methyl group, an ethyl group, Alkyl groups such as propyl groups, methoxy groups, ethoxy groups,
Alkoxy groups such as propoxy groups, dimethylamine groups,
111 is a dialkylamino group such as a diethylamino group, a dialkylamino group such as a dibenzylamino group, a diarylamino group such as a diphenylamino group, a nitrogen atom such as chlorine or bromine, a nitro group or a hydroxyl group, 111 is a methyl group, an ethyl group, etc. represents an alkyl group such as a benzyl group, an aralkyl group such as a benzyl group, or an aryl group such as a phenyl group. ] [11G, H 0. Bll or R11 is a hydrogen atom,
Alkyl groups such as methyl, ethyl and propyl groups, alkoxy groups such as methoxy, nidoxy and propoxy groups, dialkylamino groups such as dimethylamino and diethylamino groups, and halogen atoms such as chlorine and bromine.

Represents a nitro group or a hydroxyl group. ] Rk (Ham is an alkyl group having 1 to 11 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted heterocyclic group, R1
4 or Hall represents a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a chloroA/substituted alkyl group, a hydroxy-substituted alkyl group, a substituted or unsubstituted 72 alkyl group, and numbers 81 and 118 and may be combined with each other to form a heterocycle containing crab. Rle or R'' is a hydrogen atom.

Alkyl groups such as methyl, ethyl, propyl, and ethyl groups; alkoxy groups such as methoxy and ethoxy groups;
Represents a halogen atom such as chlorine or bromine. Examples of the heterocyclic group of B2m include a pyridyl group, a furyl group, a chenyl group, an indolyl group, a pyrrolyl group, a quinolyl group, and a carnotoglyl group.

Examples of substituents on the 722 group or heterocyclic group of R1 include alkyl groups such as methyl and ethyl groups, and alkoxy groups such as methoxy and ethoxy groups. Also.

Examples of the 7ralkyl group for R14 or R11 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.

The heterocycle formed by bonding R14 and Rfil to each other includes a morpholine ring. ] [H, 1m is a hydrogen atom, a halogen atom such as chlorine, bromine, R29 is a hydrogen atom, a halogen atom such as chlorine, bromine,
Alkyl groups such as methyl group and ethyl group, alkoxy groups such as methoxy group and ethoxy group, dialkylamino group such as dimethylamino group, diethylamino group, dibutylamino group, dibenzylamino group, dibenzyl substituted with chloro/I/ It represents a cyalkylamino group such as an amino group, a nitro group, a halogen atom such as cyanogen chlorine, or atom A, or an alkyl group such as a methyl group or an ethyl group. ]81 [Hat is a hydrogen atom, a halogen atom such as chlorine, bromine,
Alkyl groups such as methyl, ethyl, butyl, methoxy, and ethoxy groups.

Alkoxy group such as butoxy group or cyano group Bat
Or 1m8 is a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, a butyl group, a substituted alkyl group such as a 2-chloroethyl group or a 2-hydroxyethyl group, or a substituted or unsubstituted benzyl group, and 8m4 or RH is a hydrogen atom ,
Halogen atoms such as chlorine and bromine.

Alkyl groups such as methyl group, ethyl group, butyl group, flukoxy group such as methoxy group, ethoxy group, cytoxy group,
Represents a dialkylamino group such as a dimethylamino group or a diethylamino group. Substituents on the benzyl group of Hat or RIB3 include alkyl groups such as methyl group and ethyl group, alkoxy groups such as methoxy group and ethoxy group,
Examples include nitro groups. ] [Ar" represents an N-alkylcarbazolyl group, and examples of the alkyl box include methyl group, ethyl group, propyl group, butyl group.] (RIB, n#1, R" kt water IA N child , ax, odor 1rl fx halogen atom, alkyl group such as methyl group, ethyl group, alkoxy group such as methoxy group, ethoxy group, nitro group or amino group Bl・
is a hydrogen 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 dialkylamino group such as a dimethylamino group, a jetyl ag) group or a dibutylamino group, Substituted or unsubstituted dialkylamino groups such as a dibenzylamino group, a chloro-substituted dibenzylamino group, a methyl-substituted dibenzyl heptadate group, a methoxy-substituted dibenzylamino group, and an N-methyl-N-benzylamino group. It represents an N-alkyl-N-aralkylamino group, a carboxy group or an ester thereof, an amino group, a hydroxy group, a cyano group, or an acetylamino group. [R40 is an N-alkylcarbazolyl group, pyridyl group, chenyl group, indolyl group,
It represents a furyl group, or a substituted or unsubstituted naphthyl group, styryl group, or anthryl group. Substituents for naphthyl, styryl, and anthryl groups include alkyl groups such as methyl and ethyl groups, alkoxy groups such as methoxy and ethoxy groups, dimethylamino groups,
Examples include dialkylamino groups such as diethylamino groups. ] (R41, R41 is a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, a butyl group, an alkoxy group such as a methoxy group, a nidoxy group, a butoxy group, a chlorine, a bromine, etc.) The group represents a dialkylamino group such as a thylamino group, and nl represents 0 or l. ] 41 [R4a, R44 is a hydrogen 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, or a norogen atom such as chlorine R4B, R
46 is an alkyl group such as a methyl group, ethyl group, propyl group, or ethyl group.

Substituted or unsubstituted 7ralkyl group, substituted or unsubstituted aryl group, 84g represents a hydrogen atom, substituted or unsubstituted phenyl group 1411, As the aralkyl group/group of R46, for example, a benzyl group, and an aryl group An example of this is a phenyl group. Substituents on aralkyl or aryl groups include alkyl groups such as methyl, ethyl, and butyl, alkoxy groups such as methoxy and ethoxy, halogen atoms such as chlorine, and dialkyl groups such as dimethylamino and diethylamino groups. An example is an amino group. ] (R41 and R49 are an alkyl group such as a methyl group or an ethyl group, or a substituted or unsubstituted phenyl group.

Represents a substituted or unsubstituted benzyl group.

Substituents include alkyl groups such as methyl and ethyl groups,
Examples include alkoxy groups such as methoxy and ethoxy groups. ] (R" t R" は aa R"HR" トM し M ': Table b s.) R11 [11fi is a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, or a substituted or unsubstituted phenyl group.] The group n is an integer of 0 or 1, and A represents a 9-anthryl group or a substituted or unsubstituted N-alkylcarbazolyl group.

Here, HIM is a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, or a substituted amino group represented by -N-R114\Rz1 (R114, 'Baa is methyl
y group, an alkyl group such as an ethyl group, a propyl group, a butyl group, a substituted or unsubstituted aralkyl group such as a benzyl group, a substituted or unsubstituted aralkyl group such as a phenyl group, and 184 and R11s It may form a ring. ) and 1m represents an integer of 0, 1.2 or 3, and when m is 2 or more, R118 may be the same group or different groups. Substituents on the aralkyl group or aryl group in R114 or BmS include alkyl groups such as methyl group, ethyl group, pro2 group, butyl group,
Examples include alkoxy groups such as methoxy and ethoxy groups, halogen atoms such as chlorine, and dialkylamino groups such as dimethylamino and diethylamine groups. ] Further, specific examples of these charge transport substances are as follows.

Compound Point Structure Formula % Formula % Compound Point Structure Formula H40
H C, H40H Compound Shop Structure Formula Compound Point Structure 2〇H3 CH.

Compound structure formula hardware store Structure formula compound store
Structural formula compound black
structure formula hardware store structure
Structural formula 2-49 Compound A Structural formula compound,
In addition to the above-mentioned exemplified compounds, polymeric substances include poly-H-'vinylcarbazole, halogenated-Boy-H-vinylcarbazole, polyvinylpyrene, and brompyrene-
Formaldehyde condensation resin, N-ethylcarbazole-
Condensation resins such as formaldehyde condensation resins.

Furthermore, for low-molecular substances, any of known charge transporting substances such as oxazole derivatives, oxadiazole derivatives, and nitro-carrying conductors of fluorenone are effective.

FIG. 1 is an enlarged sectional view of an electrophotographic photoreceptor showing an embodiment of the present invention. This photoreceptor is bottomed so that a charge generation layer 22 and a charge transport layer 33 are provided on a conductive support 11 to form a photosensitive layer 44 .

The conductive support used in the present invention is 7/I/
Metal plates, drums, or foils made of miniram, nickel, chromium, etc., plastic films with thin layers of aluminum, tin oxide, indium oxide, chromium, palladium, etc., and paper coated or impregnated with conductive substances. A plastic film or the like is used.

The charge generation layer 22 is made of a liquid in which a specific disazo compound represented by the general formula (1) shown above is made into fine particles by means such as a Zeel mill, and dispersed in a suitable solvent, or if necessary, a binder resin is added thereto. A dispersion in which .

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

It is preferably 0.05 μm, and the proportion of the disazo compound in the charge generation layer 22 is 10 to 100% by weight, preferably 30 to 95% by weight. The thickness of the charge generation layer 22 is 0.01. Below c+m, sensitivity is poor, and above 5 μm, potential retention is poor. Furthermore, if the proportion of the disazo pigment in the charge generation layer is less than 10% by weight, the sensitivity will be low.

The charge transport layer 33 is formed by coating the charge generation layer with a solution in which the various charge transport substances described above and a binder resin are dissolved in a suitable solvent such as tetrahydrofuran.

Here, the proportion of the charge transport substance contained in the load transport layer 33 is 10 to 80% by weight, preferably 25 to 75% by weight.
The film thickness is 2 to 100 μm, preferably 5 to 4 μm.
It is 0 μm.

The ratio of the charge transport substance contained in the charge transport layer 33 is 10
If it is less than 80% by weight, the sensitivity is poor, and if it is more than 80% by weight, the film becomes brittle, crystals are deposited, and the charge transport layer 33 becomes cloudy, which is not preferable.

Further, if the thickness of the charge transport layer 33 is 2 μm or less, the potential is not maintained well, and if the thickness is 100/Im or more, the residual potential becomes high.

The binder resin for the charge generation layer 22 used here includes at least one of polyester resin, butylene ethyl cellulose resin, epoxy resin, acrylic resin, vinylidene chloride resin, polystyrene, polycitadiene, and their monomers. Examples include copolymers contained in 1)', which may be used alone or in a mixture of two or more.

Examples of the binder resin for the charge transport layer 33 include polycarbonate resin, polyester resin, polystyrene, polyurethane resin, epoxy resin, acrylic resin, silicone resin, and copolymers containing at least one of these monomers. , they may be used alone or in a mixture of two or more.

Furthermore, various additives can be added to the charge transport layer 33 for the purpose of improving flexibility or durability. Examples of additives used for this purpose include halogenated/N2 fins, dialkyl A/7 tallate, and silicone oil. A barrier layer may be provided between the charge generation layer 22, an intermediate layer between the charge generation layer 22 and the charge transport layer 33, and an overcoat layer may be provided on the charge transport I@33.

In addition, the disazo compound of the general formula (1) according to the present invention can 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). It can also be used.

Effects The structure of the present invention is as described above, and as is clear from the examples described later, the electrophotographic photoreceptor of the present invention is easy to manufacture.
However, it has excellent properties such as stable characteristics even when the photoreceptor is used repeatedly.

EXAMPLES Next, the present invention will be specifically explained using Examples, but the embodiments of the present invention are not limited thereby.

49'lJ1 76 parts by weight of disazo compound A I-32, 1260 parts by weight of a tetrahydrofuran solution (solid scrap [296) of polyester resin (Vylon 200.■ manufactured by Toyobo Co., Ltd.),
3,700 parts by weight of tetrahydrofuran and 3,700 parts by weight of tetrahydrofuran were pulverized and mixed in a 2-luminescence mill, and the resulting dispersion was coated on the A/I/Mi surface of an aluminum-deposited polyester paste (conductive support) using a doctor blade, and then Dry,
A charge generating layer with a thickness of about 1 μm was formed.Meanwhile, 2 parts by weight of charge transport material 2-29, 1300% polycarmenate resin (Panlite, 1300% Teijin 2!: It part and tetrahydrofuran 16 Jyusha) were formed. After mixing and dissolving the above components to form a solution, this was applied onto the charge generation layer using a doctor blade and dried at 80° C. for 2 minutes and then at 100° C. for 5 minutes to form a charge transport layer with a thickness of about 20 μm, Laminated photoreceptor A1yI shown in FIG.
l-Created.

Example 1 except that the disazo compound and charge transport substance shown in Table 1 below were used in place of the disazo compound Al-32 and charge transport substance 2-29 used in Example 1. Photoreceptor A2-30 was produced in the same manner.

These photoreceptors A1 to A30 were tested using an electrostatic copying paper tester (5p428 type manufactured by Kawaguchi Electric Seisakusho) [, -
After performing corona discharge of 6KV for 20 seconds to make it negatively charged, it was left in a dark place for 20 seconds, and the surface potential Vp at that time.

(V), then irradiate the surface with light using a tungsten lamp at an illumination intensity of 1.5 lux, find the time (seconds) until the surface potential reaches VpoO-, and calculate the exposure in' ( lux seconds) was calculated. The results are shown in Table-1.

(The following is a blank space) Table 1 One more photoreceptor of the present invention A I, A 11 and A
21 was attached to a copying machine Coby P-500 manufactured by Ricoh Co., Ltd., and image production was repeated 10,000 times. As a result, clear images were obtained from all photoreceptors. From this, it can be understood that the photoreceptor of the present invention has extremely excellent durability.

[Brief explanation of the drawing]

FIG. 1 is an enlarged sectional view showing an example of the structure of the electrophotographic photoreceptor of the present invention.

Claims (1)

[Scope of Claims] 1. An electrophotographic photoreceptor having a photosensitive layer provided on a conductive support, in which the photosensitive layer has the following general formula (1) C, where R1 and R8 are hydrogen or a lower alkyl group. , substituted or unsubstituted aralkyl group, substituted or unsubstituted aromatic group, substituted or unsubstituted heterocyclic group R, and R
2 may be the same or different. Further, R1 and the bird may jointly form a ring. ] An electrophotographic photoreceptor characterized by containing a disazo compound represented by the following.