JPS59185342A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a good toner image by incorporating a specified hydrazone type compd. CONSTITUTION:A photosensitive body contains a compd. represented by formula I in which R1, R2 are each optionally substd. alkyl, aralkyl, or aryl, but both are not alkyl at the same time, and R3 is H, halogen, alkyl, or alkoxy. Said compd. can be applied to all the types of photosensitive bodies using org. photoconductive compds., and above all, preferably used for the electrostatic charge transfer layer of the photosensitive layer functionally divided into the charge generating layer and the transfer layer, and the transfer layer is preferably formed on the generating layer. Said compd. itself has no film forming ability, so it is mixed with a binder resin to form the transfer layer. Such a hydrazone type compd. transfers positive holes to inject the holes produced from the generating layer to the transfer layer, then they reach the surface to neutralize negative charge and form an electrostatic charged image, and a good toner image is formed on the surface of the photosensitive body with a positively charged developer. Such a photosensitive body is good in sensitivity, low in residual potential, small in its change even after repeated uses, and it can be used for not only copying machines but widely for laser printers, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor having a photosensitive layer entirely containing a novel organic photoconductive material consisting of a hydrazone compound.

Conventional electrophotographic photoreceptors include those using inorganic photoconductive materials such as selenium, cadmium sulfide, and zinc oxide, and those using poly-N
- Photoconductive polymers such as vinylcarbazole and 1-phenyl-6-(p-diethylaminostyryl)
It is known to use low-molecular rMIK photoconductive substances such as -5-(p-diethylaminophenyl)pyrazoline.

In the case of low-molecular organic photoconductive substances, the present inventors believe that by selecting an appropriate binder resin, it is possible to form a photosensitive layer with good film formability. As a result of extensive research, we discovered that by using a hydrazone compound represented by the following general formula (1) in the photosensitive layer, it was possible to obtain a photoreceptor that is extremely useful for simulator photography, and we have arrived at the present invention. be.

The present invention is based on the general formula (1) (wherein R1 and R2 are in-chain or branched alkyl groups such as methyl, ethyl, propyl, butyl, aralkyl groups such as benzyl and phenethyl, or phenyl, naphthyl, and tolyl). represents an aryl group such as
The alkyl group, aralkyl group or aryl group may have a substituent 'f''p>, and the substituent is methyl,
Alkyl groups such as ethyl, alkoxy groups such as methoxy, ethoxy, propoxy, butoxy, dimethylamino,
diethylamino, dipropylamino, dibutylamino,
Substituted amine groups such as dibenzylamino and diethylamino, halogen atoms such as chlorine, bromine, and iodine are present, and R1 and R2 are both alkyl groups.
Alloys are excluded, and R3 is a hydrogen atom, a halogen atom such as chlorine, bromine, or iodine, a linear or branched alkyl group such as methyl, ethyl, propyl, butyl, or methoxy, ethoxy, propoxy, butoxy, etc. An electrophotographic photoreceptor characterized by having a hydrazone system represented by an alkoxy group (representing an alkoxy group).

All specific examples of the hydrazone compound represented by the general formula (1) are shown below.

Compound f11 The hydrazone compound represented by general formula (1) used in the present invention is represented by general formula (2) (wherein R1 and R2 have the same meaning as R1 and R2 in general formula (1)). ) and an aldehyde represented by the general formula (6) (in which R3 has the same meaning as R3 in the general formula (1)) in a solvent by a conventional method. from

The electrophotographic photoreceptor having a hydrazone compound represented by the general formula (1) can be applied to any type of electrophotographic photoreceptor using a +f type photoconductive substance, but preferred types include: (1) A charge-transfer complex formed by a combination of an electron-donating substance and an electron-accepting substance, (21 organic photoconductor sensitized by adding all dyes, (5) Pigment in the hole matrix) Dispersed ones, 6- (4) Functionally separated ones into a charge generation layer and a charge transport layer, (5) Ones whose main components are an organic photoconductor and a eutectic complex consisting of a dye and 11 cloves, (6 ) There are charge transfer complexes containing all organic or inorganic charge generating materials, among which (3)
- (6) are desirable types. Furthermore, in the case of a photoreceptor of type (4), the charge transport material used in the charge transport layer of the photoreceptor, which is functionally separated into a charge generation ring and a charge transport layer, is represented by general formula (1). When a hydrazone compound is used, the sensitivity of the photoreceptor is particularly good and the residual potential is low. Further, in this case, a decrease in sensitivity and an increase in residual potential during repeated use can be suppressed to a practically negligible level. Therefore, the (4) type photoreceptor will be explained.

As for the layer structure, a conductive layer, a charge generation layer, and a charge transport layer are essential.The charge generation layer may be either above or below the charge transport layer. In this case, it is preferable to stack a conductive layer, a charge generation layer, and a charge transport layer in this order, mainly from the viewpoint of physical strength and, in some cases, from the viewpoint of chargeability. An adhesive layer may be provided for the purpose of improving the adhesiveness between the conductive layer and the charge generation layer.

The conductive layer only needs to be imparted with conductivity, and may be a conventionally used type of conductive layer. As the material for the adhesive layer, various conventionally used binders such as casein are used. The appropriate thickness of the adhesive layer is 0.1 to 5 microns, preferably 0.5 to 6 microns.

The charge generation material used in the charge generation layer is a material that absorbs light and generates all charge carriers with extremely high efficiency.
Preferred materials include inorganic substances such as selenium, selenium-tellurium, selenium-arsenic, cadmium sulfide, amorphous silicon, pyrylium dyes, thiopyrylium dyes, triarylmethane dyes, Contains various substances such as thiazine dyes, cyanine dyes, phthalocyanine pigments, perylene pigments, indigo pigments, thioindigo pigments, quinacridone pigments, squaric acid pigments, azo pigments, and polycyclic quinone pigments. Ru. The thickness of the charge generation layer is preferably 5 tt or less, preferably 0.05 to 3 μm.

The charge generation layer is the charge generation material used. It is also provided by means such as vacuum evaporation, sputtering, glow discharge or coating. When coating, the charge-generating material may be provided without a binder, as a resin dispersion, or as a uniform bath containing the binder and the charge-generating material.

When the charge generation layer is formed by applying a resin dispersion ti, 7i: or a solution of the charge generation material, the ratio of the binder in the charge generation layer is 80% or less, since a large amount of binder used will affect the sensitivity. Preferably, the amount is 40% or less. As the binder used in the charge generation layer, conventionally used yuzu bark such as polyvinyl butyral can be used.

9- Providing a charge transport jΔ on the charge generation layer provided by any of the above methods. The thickness of the charge transport layer is 5 to 60 microns, preferably 8 to 20 microns.

Since the hydrazone compound used in the present invention itself does not have a film-forming ability, a charge transport layer is formed by dissolving a solution in a suitable organic solvent together with various binder resins and drying the solution by a conventional method. As the binder, all conventionally used binders such as acrylic resin and polycarbonate resin can be used. Or light that itself has the ability to transport enemies like poly-N-vinylcarbazole? Tetraelectric polymers can also be used as binders.

The hydrazone compound used in the present invention has hole transport properties, and when using a photoreceptor in which a conductive layer, a charge generation layer, and a charge transport layer are laminated in this order, the surface of the charge transport layer must be negatively charged. When exposed to heat, charged, and exposed to light, holes generated in the charge generation layer are injected into the charge transport layer in the exposed area, and then reach the surface, neutralizing the negative charge and causing a decrease in the surface potential. A static contrast occurs between the exposed area and the unexposed area.

In order to visualize the image, a conventional developing method can be used.

(4) Regarding photoreceptors other than this type, detailed explanations are omitted here as they are detailed in numerous documents that have been published up to this point.

The electrophotographic photoreceptor of the present invention can be used not only for electrophotographic copying, but also for laser printers, C! RT printer,
It can also be widely used in electrophotographic application fields such as electrophotographic plate making systems.

Next, examples of the present invention will be shown.

Example 1 Ammonia water bath of casein on an aluminum plate I&C casein 11.2 f, 28% ammonia water 12, water 222 ml)
' Apply with Meyer Par and dry, coating amount 1. O97m
Adhesion of 2 r@full shape was 2. Next, the following structure '(r-'!
Disazo pigment 51 and butyral resin (degree of butyralization 66 mol%) 22 were mixed in 95 ml of ethanol. After being dispersed together with the solution bathed in water, the charge generating layer was coated on the adhesive layer to form a charge generating layer with a coating weight of 0.2 r/m2 after drying.

Next, the exemplified hydrazone compound H-1ffi5f and Hollyshi 4,4'-dioxydiphenyl-2,2-10 van carbonate (viscosity average molecular weight 30,000) 51 were coated on the charge generating layer in which 150 ηdK of dichloromethane was dissolved and dried. The entire electrical protection transport layer was formed with a coating amount of 10 f/m2. The electrophotographic photoreceptor produced in this way was used as an electrostatic copying paper test equipment MOaθl5P-428 manufactured by Kawaguchi Electric Co., Ltd.
corona charging with Q5KV using 'e' static method,
After being held in a dark place for 10 seconds, it was exposed to an illuminance of 5'lux'''c and #f electric time characteristics were investigated.

The initial potential is Vo (V), the potential retention rate for 10 seconds in the dark is Fly (%), and the half-decay exposure is B (lux, s
θC) shows the charging characteristics of this photoreceptor.

Vo-630V, Rv 99%, i% 11.11
ux, sec Examples 2 to 8 A pigment having the following structure was vacuum-deposited on an aluminum plate with a thickness of 100 μm to form a charge generation layer with a thickness of 0.15 μm (Zen Formation Co., Ltd.) 5
1 and the above-mentioned exemplary hydrazone compounds H-2 to H-1115
r and a solution 'f dissolved in 150 ml of total dichloromethane!
: It was coated on the charge generation layer and dried to form a charge transport layer with a coating amount of 1117 m2. The charging characteristics of the produced electrophotographic photoreceptor were investigated in the same manner as in Example 1. The results are shown in the table below.

13- Charging characteristics 2 H-26209910, 5 3H-36359910, 9 4I (-46109910, 2 5H-56509912, 3 6H-66309910, 6 7H-7610999, 9 8H-86339910, 7 Example 9 Selenium on an aluminum plate Tellurium (10% tellurium) was deposited in full vacuum to form a charge generating layer with a thickness of 0.8 μm.

Next, the same charge transport layer as used in Example 1 was applied and dried to give a coating weight of 11 f/m2.

The chargeability of the produced electrophotographic photoreceptor was examined in the same manner as in Example 1.

Vo-585V%RV 97%, EV28.31ux,
sec Example 10 14- Hydrazone compound H-i5y used in Example 1 and BoI
J-IJ-vinylcarbazole (molecular weight 300,000) 5fk
β-type steel phthalocyanine 1. After dispersion, it was applied and dried on the casein layer of the aluminum plate provided with the casein layer used in Example 1 to give a coating amount of 10 f/m2.

The electrostatic charge of the produced electrophotographic photoreceptor was measured in the same manner as in Example 1, and the following characteristic values were obtained. However, the charging polarity was set to 10.

Vo+495V, Rv88%, E'h 24.21
Example 11 A 0.2 mm J* molybdenum plate (substrate) with a clean surface was fixed at a predetermined position in a glow discharge deposition tank. Next, the entire thin circle was evacuated to a vacuum level of about 5 x 10-6 torr. Thereafter, the input voltage of the heater was increased to stabilize the molybdenum substrate temperature at 150°C. After that, hydrogen gas and silane gas (15% violet to hydrogen gas) were introduced into the tank, and the gas flow rate and main valve of the deposition tank were fully adjusted to 0.5t.
Stabilize it to orr. Next, a high frequency power of 5 MH2 was applied to the induction coil to generate glow discharge inside the coil in the tank, resulting in an input power of 60 W. An amorphous silicon film was grown on the substrate under the above conditions, and the same conditions were maintained until the film thickness reached 2 μm, after which glow discharge was discontinued. After that, the heating heater and high frequency power supply are turned off, and the substrate temperature reaches 100℃.
After waiting for this to occur, the hydrogen gas and silane gas outflow valves were closed, and after the temperature inside the tank was lowered to below k10-''' torr, the pressure was returned to atmospheric pressure and the substrate was taken out. A charge transport layer was formed in exactly the same manner as in Example 1.

The photoreceptor thus prepared was placed in a charging/exposure experimental apparatus, charged with corona at -6 KV, and immediately irradiated with a light image. The light image was illuminated through a transmissive test chart using a tungsten lamp light source. Immediately thereafter, a positively charged developer (including all toner and carrier) was cascaded onto the photoreceptor's rear surface to obtain a good toner image on the photoreceptor surface.

Claims (1)

[Claims] (1) General formula (11 (wherein R1 and R2 represent an alkyl group, an aralkyl group, or an aryl group that may have a substituent, except when R1 and R2 are both alkyl groups. An electrophotographic photoreceptor comprising a hydrazone compound represented by n (representing a hydrogen atom, a halogen atom, an alkyl group, or an alkoxy group).