JPS62201451A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To enhance the sensitivity of a photosensitive body by forming a layer containing a specified styrene compound as an electrostatic charge transfer material. CONSTITUTION:In the case of the functionally separated multilayer photosensitive body, a charge generating pigment is vapor deposited on a conductive substrate or dispersed or mutually dissolved into a resin and applied to the conductive substrate, and on this layer the charge transfer layer containing the compound represented by formula I or II in which each of Ar1-Ar3 is phenyl optionally substituted by halogen, alkyl, alkoxy, or nitro. In this case, this compound is used in an amount of 40-150wt% of the resin. When the charge generating pigment is dispersed into the charge transfer medium, this pigment is dispersed or mutually dissolved into the binder resin in an amount of 50-300wt% of the binder resin.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an electrophotographic photoreceptor, and more particularly to a photoreceptor that has excellent electrophotographic sensitivity by containing a specific charge transport substance.

(Prior Art) Conventionally, charge transport materials for photoreceptors (hereinafter sometimes referred to as OPC) mainly containing organic pigments include poly-N-vinylcarbazole, 2.5-bis(4-diethylaminophenyl)-1, 3゜4-oxadiazole and 2.4. Ll
- Various electron transport substances or hole transport substances such as linitrofluorenone are known.

(Technical problem to be solved by the invention) Although the above-mentioned charge transport substance has a sensitizing effect depending on the photoconductive material used in combination, it is still not sufficient when considering the design of a more practical photoreceptor. It was something.

(Means for Solving Problem 11) The present invention uses a specific styrene compound represented by the following general formula as a charge transporting substance used in OPC. That is, as a charge transport substance, a specific compound represented by the following general formula, where Ar and ~Are are substituted or unsubstituted phenyl groups, and the substituent is a halogen atom, an alkyl group, an alkoxy group, or a nitro group, is used. .

(Function) Photosensitivity using a charge transport material such as poly-N-vinylcarbazole, which is conventionally known by using a specific compound as shown in formula (1) or (II) above, as a charge transport material. A remarkable sensitizing effect can be obtained compared to the body. The fact of this effect will be explained in detail in the Examples shown below, but the sensitivity for the I compound can be summarized as shown in the following table.

(No description below) Table 1 It is clear from Table 1 that the styrene compound of the present invention exhibits particularly excellent action as a charge transport material.

(Effects of the Invention) The present invention employs the specific compound represented by the above-mentioned formula (I) or (1'[) as a charge transport substance,
It becomes possible to significantly increase the sensitivity of the photoreceptor.

Therefore, when a photoreceptor containing this charge transporting substance is used in an electrophotographic copying machine, a laser printer, etc., the sensitivity is fast and clear copies without fog can be obtained.

Further, the photoreceptor can be manufactured at a lower cost than when Se or a-3i is used, and the copying speed can be increased compared to a photoreceptor of the same cost.

(Embodiment) As long as the photoreceptor in the present invention uses a specific compound represented by the above formula (1) or ([1) as a charge transport material, a charge generating pigment layer (
CGL) and a resin layer (CTL) containing a charge transporting TvA substance is provided thereon, or a composition in which a charge generating pigment is dispersed in the charge transporting medium is provided on a conductive substrate, etc. Either one can be used.

As the resin used for forming the photosensitive layer, any resin conventionally used in this field, such as epoxy resin, silicone resin, urethane resin, acrylic resin, saturated polyester resin, polycarbonate resin, alkyd resin,
Examples include electrically insulating resins such as vinyl resins and photoconductive resins such as polyvinylcarbazole.

In the case of the above-described first type of photoreceptor, that is, a functionally separated multilayer photoreceptor, a phthalocyanine pigment, a perylene pigment, a disazo Dn material, a trisazo pigment,
A charge-generating pigment such as a quinacridone pigment is provided as a vapor deposited layer or a resin Dn material-dispersed suspension, and a charge transport layer containing a compound represented by the above-mentioned formula (1) or (n) is provided thereon. In this case, the compound is used in an amount of 40 to 150, preferably 70 to 100 parts by weight per 100 parts by weight of resin.

When the amount is more than the above range, it is unfavorable in terms of photo fatigue and ozone resistance, and when it is less than the above range, sufficient sensitization is not observed.

In addition, in the second type of photoreceptor described above, that is, a type in which a charge-generating pigment is dispersed in a charge transport medium, the amount of the charge-generating pigment is 50 to 300 parts by weight, preferably 70 to 150 parts by weight, per 100 parts by weight of the binder resin. The compound represented by (1) or (II) 2 is used after being dispersed or dissolved in an amount of 40 to 150, preferably 70 to too, parts by weight.

These compounds used in the present invention are represented by the above-mentioned general formula, and include, for example, compounds having the following structural formula (not described below). Among these, No, 2.5.6°7.17
．． 1B, 19.20 is preferably used.

Furthermore, charge transport substances known per se can also be used in combination with the above-mentioned styrenic compounds.

Specifically, it is a hole transport material or an electron transport material, and examples of suitable hole transport materials include poly-N-vinylcarbazole, phenanthrene, N-ethylcarbazole, 2,5
-diphenyl-1゜3.4-oxadiazole, 2,5
-bis-(4-diethyleneaminophenyl)-1,3°4-oxadiazole, bis-diethylaminophenyl-1,3,6-oxadiazole, 4°4°-bis(
diethylamino)-2,2°-dimethyltriphenylmethane, 2,4.54 riaminophenyl imidazole,
2,5. -bis(4-diethylaminophenyl)-1□
3.4-triazole, l-phenyl-3-(4-diethylaminostyryl)-5-(4-diethylaminophenyl)-2-pyrazoline, p-diethylaminobenzaldehyde-(diphenylhydrazone), etc. Examples of transport substances are 2-nitro-9-fluorenone, 2゜7-sinitro-9-fluorenone, 2.4
．． 7-trinitro-9-fluorenone, 2,4,5°7
-tetranitro-9-fluorenone, 2-nitrobenzothiophene, 2,4.8-trinidrothioxanthone,
These include dinitroanthracene, dinitroacridine, and dinitroanthraquinone.

In producing the photoreceptor, the layer-forming composition as described above can be formed by coating means such as barcode coating or blade coating, except for the case of vapor deposition. In the case of the first type of photoreceptor, the CGL is 0.05 to '
1. Qpm and CTL are formed with a layer thickness of 10 to 25 μm. In the case of the second type of photoreceptor, the photosensitive layer is formed with a layer thickness of 5 to 15 μm.

In implementing the photoreceptor of the present invention, it is preferable to use the first type, that is, a functionally separated photoreceptor consisting of two layers, CGL and CTL, since higher sensitivity can be obtained.

(Example 1) A cyclohexanone solution of metal-free phthalocyanine (weight ratio 2/75) was dispersed for 3 minutes using an ultrasonic disperser. To this dispersion, a polyester resin solution of TeI/Rahydrofuran (weight ratio 2/75) was added at regular intervals, and ultrasonic dispersion was performed for 2 minutes to prepare a pigment dispersion.

This pigment dispersion was applied to a conductive aluminum substrate using a bar coater to form a carrier generating layer (CGL: resin, pigment ratio 1/1) of 1.0 μm (1 inch thick film when dried).

Next, among the charge transport materials described above, compound No. 5 was dissolved in benzene at a weight ratio of 7:10 to the polycarbonate resin to prepare a carrier transport layer (CTL) coating liquid.

This coating solution was applied onto the above CGL using a bar coater so that the film thickness (when dry) was 17 μm.

In this way, the obtained laminated photoreceptor was used as a commercially available plague meter E.
P A (electrostastic paper
Sensitivity was measured using an analyzer (manufactured by Kawaguchi Electric). In this measurement, first the surface of the photoreceptor was set at -600V.
Then, exposure was performed using a 4QLux halogen lamp, and the half-reduced exposure amount (Lux・sec) obtained at this time was
) was taken as the sensitivity.

As a result, the above-mentioned photoreceptor of the present invention has a power of 3.3 Lux.
It was found that it has a high sensitivity of sec.

When a photoreceptor with this layered structure was loaded as a master into a commercially available electrostatic copying machine (DC-111 manufactured by Sanda Kogyo, modified to have a negative charge specification) and a copying test was performed, clear copies with no fog were obtained. Obtained.

Next, a photoreceptor with the same configuration was formed on an aluminum drum with a diameter of 120 μl, and a commercially available electrostatic photocopying machine (Mita Kogyo D (-513Z, modified to have a negative charging specification)) was used. When loaded and copied at a high speed of 50 copies per minute, clear copies without fog were continuously obtained.As a result, the laminated photoreceptor of the present invention has a high copying speed sufficient to withstand high speed copying. It has become clear that it has sensitivity.

(Example 2) A CT1 layer was formed on the CGL of Example 1 using a CTL coating liquid having the same formulation except that the compound N0118 was used as a charge transport substance.

The sensitivity of this laminated photoreceptor was determined to be 4 (using EPA) and was found to have a high sensitivity of 3.4 Lux-see.

(Example 3) Regarding the laminated photoconductor on the master of Example 1, the pigments were changed from phthalocyanine-based pigments to disazo pigments (Guianpuru-1C, r, 21180) and perylene pigments (N, N'
A photoreceptor was prepared in the same manner except that the diimide (dimethylperylene-3,4,9,10-tetracarboxylic acid diimide) was used.

When the half-life exposure of these two types of laminated photoreceptors was measured using EPA, the following excellent values were obtained: Disazo pigment 3.5 Lux sec Perylene pigment 4. OLux・sec (Comparative Example) Three types of master-like laminated photoreceptors were prepared in the same manner as in Example 1 and Example 3 except that PVK was used instead of compound No. 5 as the charge transport material. did.

When the half-life exposure of these three types of laminated photoreceptors was measured using EPA, the following results were obtained.

Phthalocyanine pigment 12 Lux-sec disazo pigment 15 Lux-sec perylene
Pigment: 16Lux·see From this, it was found that when PVK was used, the pestilence was lower than when the charge transport material according to the present invention was used.

(Example 4) A coating solution for a single-layer photoconductor was prepared using the following formulation.

β-type phthalocyanine (manufactured by BASF) 8 parts by weight No. 6
Compound 70 parts by weight of hyteritene chloride
Resin (Saran Resin manufactured by Tau Chemical) 100 parts by weight Tetrahydrofuran 1200 parts by weight The above formulation solution was placed in a stainless steel ball mill and dispersed for 24 hours to obtain a uniform coating solution. Next, a photoreceptor was prepared using a doctor blade so that the above coating solution was coated on an aluminum plate having a thickness of 80I1m to a thickness of 7 μm (when dry).

When I created a half-reduced exposure amount using EPA (STAT ■ mode) in the same way as in Example 1, it was 8°3 Lux-se.
It was found that it has a high sensitivity of c.

Next, the above coating liquid was applied to a 78φ aluminum drum to produce a drum-shaped photoreceptor. When this photosensitive drum was loaded into a commercially available copying machine (DC-11 made by Sanda Kogyo, but modified to have a negative charging specification) and copies were made at a speed of 1/1/1, clear copies with no fog were obtained. .

1 General embroidery friend Sanda Kogyo Co., Ltd.

Claims (7)

[Claims] (1) As a charge transport substance, the following general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ In the formula, Ar_1 to Ar_8 are substituted or unsubstituted phenyl groups and are substituents. An electrophotographic photoreceptor comprising a layer containing a compound using a halogen atom, an alkyl group, an alkoxy group, or a nitro group. (2) The photoreceptor according to claim 1, wherein the photosensitive layer is a single-layer photosensitive layer comprising the charge-transporting substance and the charge-generating pigment contained in an electrically insulating binding medium. (3) The charge generating pigment is present in an amount of 5 to 100 parts by weight per 100 parts by weight of the binder, and the charge transport material is also present in an amount of 1 to 100 parts by weight.
The photoreceptor according to claim 2, wherein the photoreceptor is contained in an amount of 0 to 50 parts by weight. (4) The photosensitive layer comprises a charge-generating layer having a charge-generating pigment provided on a conductive substrate, and a charge-transporting layer containing the charge-transporting substance thereon.
Photoreceptor described in section. (5) The charge generation layer binds the charge generation pigment to the binding medium 100.
The photoreceptor according to claim 4, wherein the photoreceptor contains 50 to 300 parts by weight per part by weight. (6) The photoreceptor according to claim 4, wherein the charge generation layer is a vapor-deposited layer of a charge generation pigment. (7) The charge transport layer binds the charge transport material to a binding medium 1.
5. The photoreceptor according to claim 4, wherein the photoconductor contains the photoreceptor in an amount of 40 to 150 parts by weight per 0.00 parts by weight.