JPS602958A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To facilitate the manufacture and to improve the suitability to repeated use by incorporating a specified disazo pigment into the photosensitive layer. CONSTITUTION:A photosensitive layer contg. a disazo pigment represented by general formula I (where each of R<1> and R<2> is lower alkyl, optionally substituted aralkyl, an optionally substituted aromatic group or an optionally substituted heterocyclic group, and R<1> and R<2> may bond to each other to form a ring) is formed on an electrically conductive support. The disazo pigment is prepd. by coupling a diazonium salt mentioned in Japan Patent Publication No. 53-95033 (unexamined) with a corresponding coupler (2-hydroxy-3-naphthoic acid hydrazide). It is preferable that the disazo pigment is incorporated into the charge generating layer of a laminate type sensitive body. Hydrazone or the like is contained in the charge transferring layer.

Description

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

PRIOR ART Photoconductors for electrophotography include inorganic photoconductors, such as those using selenium and its alloys, or photoconductors with dye-sensitized zinc oxide dispersed in a binder resin, and organic photoconductors. For example, a charge transfer complex of 2,4,7-1-dinitro-9-fluorenone (TNF) and poly-N-vinylcarbazole (PVK) is known as a typical example. There is.

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

For example, the currently widely used selenium photoreceptor has difficult manufacturing conditions, high manufacturing costs, and is difficult to process into a belt shape due to its lack of flexibility.
It is also sensitive to heat and mechanical 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. It has mechanical drawbacks, and as a photoreceptor for plain paper copying machines, which is normally used repeatedly, there are many problems with durability.

In addition, photoreceptors using charge transfer complexes of TNF and PVK have low sensitivity and are unsuitable as photoreceptors for high-speed copying machines.In recent years, extensive research has been carried out to eliminate these drawbacks of photoreceptors. Progress has been made, and various organic photoreceptors have been proposed. Among these, there is a layer (hereinafter referred to as "charge generation layer") containing a substance that generates charge carriers when irradiated with light (hereinafter referred to as "charge generation material"), and a layer that receives and transports the generated charge carriers. A laminated photoreceptor consisting of a layer (hereinafter referred to as "charge transport layer") mainly composed of a substance (hereinafter referred to as "charge transport material") generally has higher sensitivity and chargeability compared to conventional organic photoreceptors. Due to its stability, it has attracted attention as a photoreceptor for plain paper copying machines, and some are in practical use.

As this type of conventional laminated photoreceptor, (1)! A thin layer in which a perylene derivative is vacuum-deposited as a charge generation layer, and an oxadiazole derivative is used in a charge transport layer (see US Pat. No. 3,871,882); (2) an organic amine of chlordiane blue as a charge generation layer; A thin layer formed by applying a solution is used, and a hydrazone compound is used as the charge transport layer (Japanese Patent Publication No. 55-4238
(see Publication No. 0) are known.

However, even though this type of laminated type photoreceptor has passed, it is true that the conventional photoreceptor has many advantages, but also has various disadvantages as described below.

The photoreceptor using the perylene derivative and oxadiazole derivative shown in (1) above has a high production cost because its charge-generating layer is formed by vacuum deposition.

The photoreceptor using chlordiane blue and a hydrazone compound shown in (2) above uses an organic amine (which is generally difficult to handle) as a coating solvent for forming a charge generation layer.
For example, it is necessary to use ethylenediamine), which has disadvantages in producing a photoreceptor.

Purpose The present invention provides an electrophotographic photoreceptor that can be easily manufactured and is suitable for repeated use.

Structure The electrophotographic photoreceptor of the present invention has the following general formula (1) (% formula %) on a conductive support (where R1 and V are a lower alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aralkyl group). represents an aromatic group or a substituted or unsubstituted heterocyclic group. R1 and R2 may be the same or different, or R1 and R2 may jointly form a ring.) It is characterized by being provided with a photoconductive layer (photosensitive layer) containing a disazo compound represented by:

Here, the lower alkyl group in general formula (1) 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. , pyrenyl group, anthraquinonyl group, etc.; examples of heterocyclic groups include chenyl group, furyl group, pyridyl group, carbazolyl group, etc.; examples of the ring formed by R1 and R2 include hexylidene ring, pentylidene ring, pensohentylide/ring; , dibenyl panthlydene ring, and the like.

Examples of direct substituents in aralkyl groups, aromatic groups, heterocyclic groups, or the ring formed by B''s- and R2 include lower alkyl groups, lower alkoxy groups, halogen atoms, cyano groups, nitro groups, and lower dialkylamino groups. can be mentioned.

Incidentally, the present invention is based on the inventor's extensive studies in order to achieve the above-mentioned object, and the inventor has found that the use of a specific disazo pigment (disazo compound) is extremely useful for the Seiko photographic photoreceptor. This was done based on the following. Also,.

The screw photoreceptor of the present invention is not limited to a single layer type photoreceptor, but rather a multilayer type photoreceptor in which the photosensitive layer is composed of a charge generation layer and a charge transport layer.

In such a laminated electrophotographic photoreceptor, the charge generation layer is formed of a layer containing a disazo pigment represented by the general formula (I).

Below, I will explain Kien 1-1 in more detail.

First, specific examples of the disazo compound represented by the general formula (I) used in the present invention are as follows.

C,H.

C,H.

These disazo compounds include the diazonium salts described in JP-A No. 53-95033 and the corresponding kaglar (2-hydroxy-3-naphthoic acid hydrazides).
can be easily produced by reacting a suitable compound with a base in an organic solvent such as N,N-dimethylformamide (DMF) to cause a coupling reaction.

By the way, as described earlier, the photoreceptor of the present invention is
The charge generating substance represented by the general formula (1) is contained in the photosensitive layer, but in an actual photoreceptor, the charge generating substance and the charge transporting substance are combined to form the photosensitive layer (photoconductive layer). layer) is formed.

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

t<” [R10 is an alkyl group such as a methyl group or an ethyl group, 2-
Substituted alkyl groups such as chloroethyl group, 2- and droxyethyl group, Bll is an alkyl group such as methyl group or ethyl group, aralkyl group such as benzyl group, oryl group such as phenyl group, R12 is hydrogen atom, chlorine, Does not represent halogen atoms such as bromine, methyl groups, ethyl groups, argyl groups such as propyl and butyl groups, alkoxy groups such as methoxy, ethoxy, propoxyl groups, butoxy groups, dialkylamino groups, or nitro groups. . ] Ar' represents a naphthyl group, anthryl group, styryl group, or a substituted product thereof; Hlll represents an alkyl group such as a methyl group or an ethyl group, an aralkyl group such as a be/zyl 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, methoxy groups,
Alkoxy groups such as ethoxy groups, dimethylamino groups,
Examples include dialkylamino methods such as diethylamino group. ]RHR14 (R14, R111 or R1? is a hydrogen atom, an alkyl group such as a methyl group, an ethyl group or a propyl group, an alkoxy group such as a methoxy group, an ethoxy group or a propokine group, a chlorine or bromine group), a rogene atom, or a nitrogen atom. B16 represents a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, or a propyl group, an alkoxy group such as a methoxy group, an ethoxy group, or a propoxy group, a dialkylamino group such as a dimethylamino group, or a diethylamino group, - dialkylamino groups such as benzylamino groups, diarylamino groups such as diphenylamino groups, chlorine, bromine, etc.
A rogene atom, a nitro group or a hydroxyl group, and HIM represent 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. ] R20BIQ (B111, HIo, 321 or R22 is a hydrogen atom, an alkyl group such as a methyl group, an ethyl group or a propyl group, an alkoxy group such as a methoxy group, an ethoxy group or a propoxy group, a dialkylamino group such as a dimethylamino group or a diethylamino group) group, a halogen atom such as chlorine or bromine, a nitro group or a hydroxyl group.] [R28 is an alkyl group having 1 to 11 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted heterocyclic group, R2
4 or R2H represents a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a chloro-substituted alkyl group, a hydroxy-substituted alkyl group, or a substituted or unsubstituted aralkyl group, and R'' and Hall are mutually They may be combined to form a nitrogen-containing heterocycle.

R16 or R2? is a hydrogen atom, a methyl group, an ethyl group,
Alkyl groups such as propyl and butyl groups, methoxy groups,
Represents an alkoxy group such as an ethoxy group, or a halogen atom such as chlorine or bromine. Examples of the heterocyclic group for R113 include a pyridyl group, a furyl group, a chenyl group, an indolyl group, a pyrrolyl group, a quinolyl group, and a carbazolyl group.

Examples of substituents on the phenyl group or heterocyclic group of R23 include alkyl groups such as methyl and ethyl groups, and alkoxy groups such as methoxy and ethoxy groups.

Examples of aralkyl groups with B24 or B2 scratches include benzyl groups, and examples of substituents for aralkyl groups include halogen atoms such as chlorine and bromine, alkyl groups such as methyl and ethyl groups, and nitro groups. can. An example of the heterocycle formed by bonding B24 and Ras to each other is a morpholine ring. ] [R28 is a hydrogen atom, a halogen atom such as chlorine, bromine,
B211 is a hydrogen atom, a halogen atom such as chlorine or bromine,
Alkyl groups such as methyl group and ethyl group, alkoxy groups such as methoxy group and ethoxy group, dialkylamino groups such as dimethylamino group, diethylamino group, dibutylamino 4, dibenzylamino group, chloro-substituted dibenzylamino group, etc. It does not represent dialkylamino groups, nitro groups, cyano groups, halogen atoms such as atoms, alkyl groups such as methyl groups, ethyl groups, etc. ] (<Ill is a hydrogen atom, a chlorine atom such as chlorine, a bromine atom, an alkyl group such as a methyl group, an ethyl group, a butyl group, an alkoxy group such as a methoxy group, an ethoxy group, a butoxy group, or a cyano group, Rn or Baa is a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, a butyl group, 2
-Substituted alkyl group such as chloroethyl group, 2-hydroxyethyl group, substituted or unsubstituted benzyl group, R114 or R5 is hydrogen atom, chlorine, bromine, etc.) -rogen atom, methyl group, ethyl group , represents an alkyl group such as a butyl group, an alkoxy group such as a methoxy group, an ethoxy group, a butoxy group, or a dialkylamino group such as a dimethylamino group or a diethylamino group. As an alkyl group such as methyl group or ethyl group, methoxy'1M
, an alkoxy group such as an ethoxy group, and a nitro group. ] (Ar' represents an N-alkylcarbazolyl group, and examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, etc.) LBH, R3?, R,
'l11 is a hydrogen atom, a halogen atom such as celline or bromine, an alkyl group such as a methyl group or an ethyl group, a methoxy group,
Alkoxy group such as ethoxy group, nitro group or amino group, Baa is hydrogen atom, nitrogen atom such as chlorine, bromine, alkyl group such as methyl group, ethyl group, alkoxy group such as methoxy group, ethoxy group, dimethylamino basis,
dialkylamino groups such as diethylamino group and dibutylamino group; substituted or substituted dialkylamino groups such as dibenzylamino group, chloro-substituted dibenzylamino group, methyl-substituted dibenzylamino group, and methoxy-substituted dibenzylamino group; N-alkyl-N-aralkyl amino group with N-methyl-N-benzylamino group, calxoxy group or its ester, amino group, hydroxy group,
Represents a cyano group or an acetylamino group. ] [R60 is N
-Alkylcarbazolyl group, pyridyl group, chenyl group,
Indolyl group, furyl group, or each substituted or unsubstituted! Represents a c-substituted naphthyl group, styryl group or anthryl group. Substituents for naphthyl, styryl, and anthryl groups include alkyl groups such as methyl and ethyl groups, and alkoxy groups such as butoxy and ethoxy groups.

Examples include diethylamino groups and dialkylamino groups such as diethylamino groups. ] (H41 and R42 are hydrogen atoms, alkyl groups such as methyl group, ethyl group, butyl group, alkoxy groups such as methoxy group, ethoxy group, butoxy group, chlorine, bromine, etc.)・Rogen atom, dimethylamino group, diethylamino group represents a dialkylamino group such as a group, and Ill represents 0 or l. ] [B4m,
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, a /%rogen atom such as chlorine, R411 and R46 are a methyl group,
Alkyl group such as ethyl group, propyl group, butyl group, substituted or unsubstituted aralkyl group, substituted or unsubstituted aryl group, R4? represents a hydrogen atom or a substituted or unsubstituted phenyl group. An example of the aralkyl group for R45 and R46 is a benzyl group, and an example of the aralkyl group is a phenyl group. In addition, substituents on aralkyl or aryl groups include alkyl groups such as methyl, ethyl, and butyl groups, alkoxy groups such as methane and ethoxy groups, nitrogen atoms such as chlorine, dimethylamino groups, diethylamino groups, etc. An example is a dialkylamino group (RQ, R40 is an alkyl group such as a methyl group or ethyl group, and substitution is also 1.< is an unsubstituted phenyl group, a substituted or unsubstituted benzyl group. is an alkyl group such as a methyl group or an ethyl group, or an alkoxy group such as a methoxy group or an ethoxy group.] /RsO (R" + P-" kt The above R" * R4Q represents the same & wo.] Re! [R52 is a water atom, an alkyl group such as a methyl group or an ethyl group, a substituted or unsubstituted phenyl group, n! is an integer of 0 or 1, A is a group or a substituted or unsubstituted N-alkylcarbazolyl group Here, BaM is a hydrogen atom, an alkyl group, an alkoxy group, a halogeno group (R54, Hllll is an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a substituted or unsubstituted aralkyl group such as a benzyl group) , represents a substituted or unsubstituted rearyl group such as a phenyl group, and may also form a field with BS4 and Ra1l), m represents an integer of 0.1.2 or 3, When m is 2 or more, BaM may be the same group or different groups. Substituents on the aralkyl group or aryl group in R54 or Hllll include methyl group, ethyl group, propyl group, butyl group, etc. Examples include alkyl groups, alkoxy groups such as methoxy groups and ethoxy groups, halogen atoms such as chlorine, and dialkylamino groups such as diethylamino and diethylamino groups. That's right.

Compound shop inn structure %formula% Compound A formula CzI(4CA C,)I401( 18 C, H40t ( Compound 7fL structural formula Compound A structural formula -13 -14 -15 CH.

-16 CH.

Compound &"Me formula compound structure Formula 2-26 -27 N -28 -29 -30 -31 -32 Compound, Liang loquat structure Formula 2:38 Compound A horizontal structure Formula-43 -44 Compound & Preparation Formula Compound point Dry structure Formula-49 -50 Compound structure ('l゛ Structure Formula 2-53 -54 -55 -56 Compound shop Mizo Residue formula Compound point Structural formula Exemplified compounds above In addition, polymer materials include poly-N-vinylcarbazole, halogenated poly-N-vinylcarbazole, polyvinylpyrene, and condensation resins such as bromopyrene-formaldehyde condensation 'fL5BW' and N-nigel'carpazole-formaldehyde condensation resin. Furthermore, for low-molecular substances, any of the known charge transporting substances such as oxazole visiting conductors, oxadiazole derivatives, and nitro derivatives of fluorenone are effective.

The accompanying drawings are representative enlarged sectional views of two sides of the electrophotographic photoreceptor according to the present invention, and FIG. FIG. 2 shows a conductive support 1 provided with a photosensitive layer 41.
1, a charge generation layer 22 and a charge transport layer 32 are provided on the photosensitive layer 1 to form a multilayer photosensitive layer 42.

Compared to the former, the latter's product/
The l'JM electrophotographic photoreceptor is more advantageous in various aspects. It is also possible to form the photosensitive layer by dispersing a disazo compound represented by the general formula (I) in a binder 4v4 resin, without using the above-mentioned charge transporting substance.

The conductive support 11 used in the present invention is a metal plate, metal drum, or gold foil made of aluminum, nickel, chromium, etc., and FAi FJ made of aluminum, tin oxide, indium oxide, chromium, palladium, etc. Examples include plastic films and paper or plastic films coated with or impregnated with an attractive substance.

In the laminated type photoreceptor, the charge generation layer 22'1 is made of a specific disazo compound represented by the general formula (I) shown above. - It is made into fine particles by means such as Lumil and dispersed in a suitable solvent, or if necessary, a dispersion liquid in which a binder resin is dissolved therein is coated on a conductive support. Furthermore, if necessary, the surface is finished by a method such as puff polishing, and the film thickness is adjusted.

The thickness of the charge generation layer 22 is 0.01 to 5 μm, preferably 0.05 to 2 μm, and the proportion of the disazo compound in the charge generation layer 22 is 10 to 100% by weight, preferably 30 to 2.
He is 95 years old.

If the thickness of the charge generation layer 22 is 0.01 μm or less, sensitivity is poor, and if it is 5 μm or more, potential retention is poor.

Further, when the proportion of the disazo pigment in the charge generation layer 22 is 10 weight leeward, the sensitivity is good.

The charge transporting layer 32 is formed by coating the charge generating layer 22 with a solution in which the various charge transporting substances described above and a binder resin are dissolved in a suitable solvent such as tetrahydrofradi. Here, the proportion of the charge transport substance contained in the charge transport layer 32 is 1 to 10 to 800 to 80 parts by weight or 2 parts by weight.
The thickness is 5 to 75 [1], and the film thickness is 2 to 100 μm, preferably 5 to 40 μm. If the proportion of the charge transport substance contained in the charge transport layer 32 is less than 10% by weight, the sensitivity will be poor, and if it exceeds 800 parts by weight, the film will become brittle or crystals will precipitate, making the charge transport layer 32 cloudy, which is not preferable. . Further, if the thickness of the charge transport layer 32 is less than 2/Jfi, the potential is not maintained well, and if it is more than 100 μm, the residual potential becomes high.

Examples of the binder resin for the charge generation layer 22 used here include polyester resin, butyral resin, ethyl cellulose resin, epoxy resin, acrylic resin, vinylidene chloride resin, polystyrene, polybutadiene, and copolymers thereof. , they may be used alone or in a mixed state of two or more.

Examples of the binder resin for the charge transport layer 32 include polycarbonate resin, polyester resin, polystyrene, polyurethane resin, epoxy resin, acrylic resin, silicone resin, and copolymers thereof, and they are one type of binder resin. Or, two or more types are used in a mixed state.

Furthermore, various additives can be added to the charge transport layer 32 for the purpose of improving flexibility or durability. Additives used for this purpose include halogenated paraffins, dialkyl heptamerates, silicone oils, and the like.

Furthermore, in the photoreceptor of the present invention, if necessary, a barrier layer is provided between the conductive support 11 and the charge generation layer 22, an intermediate layer between the charge generation layer 22 and the charge transport layer 32, and a charge transport layer. An overcoat layer may also be provided over 32.

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

Example 1 Disazo compound A1-1 was mixed with 76 layers of polyester resin (Vylon 200, Toyobo JA Co., Ltd.)
1260 parts by weight of Hydrof 2/solution (solid content concentration 2t),
and 3,700 parts by weight of tetrahydrofuran were pulverized and mixed in a gil mill, and the resulting dispersion was applied onto the aluminum surface of an aluminum-deposited polyester base (conductive support) using a doctor blade, and left to air dry. , 1-
7-A charge generation layer having a thickness of about 1 μm was formed.

On the other hand, 2 parts by weight of the drug transport substance 4π2-29, 2 parts by weight of polycarbonate 4i'l fat (1300 for Panlite, Teijin W Co., Ltd.), and 1 part by weight of tetrahydrofuran.
After mixing and dissolving the six-layered part to form a solution, this was applied onto the charge generation layer using a doctor blade, bent at 80°C for 2 minutes, and then dried at 100°C for 5 minutes to form a charge with a thickness of about 20 μm. A transport layer was formed to produce a laminated photoreceptor &1 shown in Figure 2g2.

Examples 2 to 10 Same as Example 1 except that the disazo compound and charge transport substance shown in Table 1 below were used instead of the disazo compound and charge transport substance 2-29 used in Example 1. Photoreceptors/A12-1O were prepared.

For these photoconductors 1 to 10, a -6KV corona discharge was performed for 20 seconds at X and S using a blue p-electronic copying paper tester (manufactured by Kawaguchi Electric Co., Ltd., model 5P428) to test the negative. After charging it, leave it in place for 20 seconds ii: 11111,
The surface potential Vpo (V) at that time is determined as 11, and then,
A tungsten lamp illuminates its surface with an illuminance of 4.5 lux and emits ℃ light! <R1 (seconds) at the time when the surface potential becomes % of Vpo after one irradiation was taken, and the exposure) % (looks/seconds) was calculated. The results are shown in Table-1.

Table-1 It is a cow, and the photosensitive body temperature of the present invention, 1, is attached to the Ricoh M Co., Ltd. copier Ricopy P-5OO, and the image is output io, ooo.
A clear image was obtained even after repeated rotations. From this fact, it can be understood that the photoreceptor of the present invention is also excellent in durability.

Effects As described above, the electrophotographic photoreceptor of the present invention has excellent properties such as being easy to manufacture and having stable characteristics even when the photoreceptor is used after recycling.

[Brief explanation of the drawing]

Figures 1 and 2 are enlarged sectional views showing two typical sides of the electrophotographic photoreceptor of the present invention.

Claims (1)

[Claims] 1. On a conductive support, a compound of the following general formula tl)C*Ha (where R1 and Rt are a lower alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic group) , or represents a substituted or unsubstituted heterocyclic group. Here,
R1 and R2 may be the same or different,
Moreover, Hl and R2 may jointly form a ring. 1. An electrophotographic photoreceptor comprising a photosensitive layer containing a disazo pigment represented by the following formula as an active ingredient.