JPH04255861A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To enhance sensitivity and to obtain superior solubility, mechanical and chemical durability by incorporating a specified hydrazone compd. CONSTITUTION:A hydrazone compd. represented by the formula is incorporated as an electric charge transferring material. In the formula, each of R<1> and R<2> is halogen, hydroxyl, alkoxy, aralkoxy, monoalkylamino, dialkylamino, monoarylamino, diarylamino, monoaralkylamino, diaralkylamino, alkyl, aryl or aralkyl, R<3> is aryl, a heterocyclic group or substd. allyl and each of l and m is an integer of 0-3. The hydrazone compd. is obtd. by condensing various aldehyde compds. with a hydrazine compd. in the presence of an acid catalyst.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor containing a hydrazone compound as a charge transport material.

0002

[Prior Art] Currently, as a photoreceptor for electrophotography, a functionally separated photoreceptor containing a charge-generating material that is photosensitized to the wavelength of the light source and a charge-transporting material that has a high charge transfer speed is often used. .

[0003] Conventionally, low-molecular conductive substances such as hydrazone compounds, styryl compounds, pyrazoline compounds, and triphenylamine compounds have been used as charge transport substances.

0004

[Problems to be Solved by the Invention] Multifunctional hydrazone compounds having a plurality of hydrazone bonds in one molecule have been developed. However, electrophotographic photoreceptors using this polyfunctional hydrazone compound as a charge transport material have problems with sensitivity, mechanical and chemical durability, solubility in polymers, etc., and a satisfactory product has not yet been obtained. do not have.

An object of the present invention is to provide an electrophotographic photoreceptor that has high sensitivity, excellent solubility, and excellent mechanical and chemical durability.

[0006]

[Means for Solving the Problems] The electrophotographic photoreceptor of the present invention contains a hydrazone compound represented by Chemical Formula 2 as a charge transporting substance.

[Formula 2] (However, R1 and R2 are a halogen atom, a hydroxyl group, an alkoxy group, a substituted or unsubstituted aralkoxy group, a monoalkylamino group, a dialkylamino group, a monoarylamino group, a diarylamino group, a monoaralkyl amino group, Represents a dialkylamino group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group, and R3 is a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group , or a substituted allyl group, and l and m each represent an integer from 0 to 3.)

The hydrazone compound of the present invention can be obtained by condensing various aldehyde compounds and a hydrazine compound in the presence of an acid catalyst.

Next, specific examples of substituents R1 and R2 of the hydrazone compound represented by formula 2 are shown in Table 1, and specific examples of substituent R3 are shown in Table 2.

[Table 1]

[Table 2]

The hydrazone compound represented by the formula 2 can be used in the same manner as ordinary charge transport materials. The form of the electrophotographic photoreceptor of the present invention is shown below.

FIGS. 1, 2, and 3 are cross-sectional views of the electrophotographic photoreceptor of the present invention. In the electrophotographic photoreceptor shown in FIG. 1, a charge generation layer 3 made of only a charge generation substance 2 or a polymer containing a charge generation substance 2 is laminated on a conductive support 1, and a charge transport substance 4 is layered thereon. This is a stack of charge transport layers 5 made of a polymer containing the same. In this case, a small amount of the charge transport material 4 may be added to the charge generation layer 3. The electrophotographic photoreceptor shown in FIG. 2 has a charge transport layer 5 laminated on a conductive support 1, and a charge generation layer 3 laminated thereon. In this case, a protective layer may be formed on the charge generation layer 3 if necessary. The electrophotographic photoreceptor shown in FIG.
A photosensitive layer 6 in which a charge generating substance 2 is dispersed in a polymer containing a charge transporting substance 4 is laminated on a substrate 1.

The charge generation layer 3 shown in FIGS. 1 and 2 is
It may be formed by vapor depositing the charge generating substance 2, or it may be formed by coating a polymer solution in which the charge generating substance 2 is dispersed. As the charge generating substance and polymer, those used in ordinary electrophotographic photoreceptors can be used. As the charge generating substance, various pigments having photosensitivity to the wavelength of the light source can be used, such as perylene pigments, azo pigments, phthalocyanine pigments, and squarium pigments. Any polymer can be used as long as it has excellent adhesive properties and is insulating.

A plasticizer may be used in the photosensitive layer 6 to improve flexibility, adhesiveness, and mechanical strength. Also,
An intermediate layer may be provided between the conductive support 1 and the photosensitive layer 6 to improve adhesion and charging properties. For coating the photosensitive layer 6 and the intermediate layer, a doctor blade, wire bar, roll coater, etc. are usually used. In the case of the electrophotographic photoreceptor shown in FIGS. 1 and 2, the thickness of the photosensitive layer 6 is 5 μm or less, preferably 0.1 to 1 μm, and the thickness of the charge transport layer 5 is 5 μm or less. is 5 to 50 μm, preferably 10 to 2
It is 0 μm. Furthermore, when an intermediate layer is provided, the thickness of the intermediate layer is preferably 1 μm or less.

[0013]

[Examples] The present invention will be explained below with reference to Examples.

(Example 1) A method for synthesizing the hydrazone compound shown by Chemical Formula 3 will be explained. 9.32 g (20 mmol) of the bis-type hydrazine compound shown in Chemical Formula 4 and 7.79 g (44 mmol) of p-diethylaminobenzaldehyde.
) in toluene under p-toluenesulfonic acid catalyst.
Refluxed for an hour. After the reaction was completed, the reaction product, the hydrazone compound of Chemical Formula 3, was separated by thin layer chromatography to obtain a yellow product in a yield of 10.66 g. The product was recrystallized using an ethanol-acetone mixed solvent. Table 3 shows the results of elemental analysis.

[Chemical formula 3]

[C4]

(Example 2) 5 g of squarium pigment obtained by reacting squaric acid with N,N-dimethylaniline, 20 g of polyester resin, 4 g of cyclohexanone
00g were mixed and dispersed for 3 hours using a shaking disperser. The obtained solution was applied onto an Al-deposited polyester film using a wire bar to form a charge generation layer having a thickness of 0.5 μm. Next, 10 g of the hydrazone compound of Chemical Formula 3 as a charge transport substance was dissolved in a polymer solution in which 10 g of polycarbonate resin was dissolved in 90 g of cyclohexanone. The resulting solution is applied onto the charge generation layer with a wire bar,
A charge transport layer having a thickness of 17 μm was formed to produce an electrophotographic photoreceptor. This hydrazone compound 1 had excellent solubility in solvents and was able to uniformly form a charge transport layer.

The electrophotographic photoreceptor thus produced was first corona charged at -6 KV in a dark place, and then exposed to light using a W lamp with an illuminance of 5 lux to examine its charging characteristics. The charging characteristics include an initial charging potential V0 after charging, and a surface potential of -
The time tD required for dark decay from 620V to -600V and the exposure amount E1/2 required for light decay from -600V to -300V were measured. Furthermore, the same operation was repeated on this electrophotographic photoreceptor, and V0 after 1000 times.
(1000), tD (1000), E1/2 (1
000) to examine durability. The results were as follows.

[0017] V0 = -783V tD = 16 seconds E1/2 = 2.9lux・sec V0 (1000) = -875V tD (1000) = 14 seconds E1/2 (1000) = 3.2lux・sec

0018
Comparative Example 1 An electrophotographic photoreceptor was produced under the same conditions as in Example 2, except that a hydrazone compound represented by Chemical Formula 5 was used as the charge transport material.

[C5]

The hydrazone compound represented by Chemical Formula 5 has low solubility in solvents and crystallized in the charge transport layer. For this reason, the light transmittance in the charge transport layer is significantly reduced, and the flexibility is poor, making it difficult to use it as a charge transport material.

(Examples 3 to 11) Electrophotographic photoreceptors were prepared under the same conditions as in Example 2, except that hydrazone compounds shown in Chemical formulas 6 to 14 were used as charge transport materials. Table 4 shows the charging characteristics of the produced electrophotographic photoreceptor.

[C6]

[C7]

[Chemical formula 8]

[Chemical formula 9]

[Chemical formula 10]

[Chemical formula 11]

[Chemical formula 12]

[Chemical formula 13]

[Chemical formula 14]

[Table 4]

[0021]

EFFECTS OF THE INVENTION The polyfunctional hydrazone compound used in the present invention is a charge transporting substance that is highly sensitive, has excellent solubility and flexibility in various solvents, and exhibits little loss of sensitivity or chemical deterioration due to repeated use. According to the present invention, it is possible to provide an electrophotographic photoreceptor with high sensitivity, excellent mechanical and chemical durability, and high printing durability. Further, the electrophotographic photoreceptor of the present invention can be applied to laser printers, liquid crystal shutter printers, LED printers, copying machines, electrophotographic engraving systems, and the like.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an electrophotographic photoreceptor of the present invention.

FIG. 2 is a sectional view of the electrophotographic photoreceptor of the present invention.

FIG. 3 is a sectional view of the electrophotographic photoreceptor of the present invention.

[Explanation of symbols]

1 Conductive support 3 Charge generation layer 5 Charge transport layer 6 Photosensitive layer

Claims (1)

[Claims] 1. An electrophotographic photoreceptor comprising a hydrazone compound represented by Chemical Formula 1. [Formula 1] (However, R1 and R2 are a halogen atom, a hydroxyl group, an alkoxy group, a substituted or unsubstituted aralkoxy group, a monoalkylamino group, a dialkylamino group, a monoarylamino group, a diarylamino group, a monoaralkyllamino group, Represents a dialkylamino group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group, and R3 is a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group , or a substituted allyl group, and l and m each represent an integer from 0 to 3.)