JPS6323162A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a photosensitive body superior in sensitivity by using a specified compound as the electric charge transfer material of a photosensitive body (OPC) composed essentially of an organic pigment. CONSTITUTION:The compound to be used as the charge transfer material is represented by the formula shown on the right in which n is 1 or 2, and each of Ar1-Ar4 is a phenyl group optionally substituted by halogen, alkyl, alkoxy, or nitro. When the photosensitive body is a functionally separated laminate type photosensitive body, it is prepared by forming on a conductive substrate the vapor deposited layer of a charge generating organic pigment, such as phthalocyanine pigments, perylene type pigments, disazo type pigments, trisazo type pigments, or quinacridone type pigments, or a layer containing said pigment dispersed into a resin, and laminating on it the charge transfer layer containing said compound of the formula dispersed in a resin in an amount of 40-150wt%, preferably, 70-100wt% of the resin.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electrophotographic sensitive material, and more particularly to a photosensitive material that has excellent electrophotographic sensitivity by containing a specific charge transporting 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 2,4.7-
) Various electron-transporting substances or hole-transporting substances such as linitrofluorenone are known.

(Technical Problems to be Solved by the Invention) Although the above-mentioned charge transport substances have an exacerbating effect depending on the photoconductive materials used in combination, they are still not sufficient when considering the design of a more practical photoreceptor. Met.

(Means for Solving the Problems) The present invention uses a specific compound represented by the following general formula as a charge transport substance used in OPC.

That is, as a charge transport substance, in the general formula shown below, n is an integer of 1 or 2; ArI to Ar4 represent substituted or unsubstituted phenyl groups, and the substituents include a halogen atom, an alkyl group, an alkoxy group, or a nitro group. Use the specific compound shown in 2.

(Function) By using the specific compounds shown above as charge transporting substances, there is a significant exacerbation effect compared to photoreceptors that use conventionally known charge transporting substances such as poly-N-vinylcarbazole. can get. The fact of this effect will be explained in detail in the examples shown below, but the sensitivity for one compound can be summarized as shown in the following table.

Table 1 It is clear from Table 1 that the specific compounds of the present invention exhibit particularly excellent effects as charge transport substances.

(Effects of the Invention) The present invention makes it possible to significantly increase the sensitivity of a photoreceptor by employing the above-mentioned specific compound as a charge transport material.

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 capri can be obtained.

81] Engraving of details (no change in content) In addition, the photoreceptor can be manufactured at a lower cost than when using Se or a-3i, and the copying speed can be increased compared to photoreceptors of the same cost. It becomes possible.

(Embodiment) As long as the above-mentioned specific compound is used as a charge transport material, the photoreceptor in the present invention includes a charge generating pigment layer (CGL) on a conductive substrate and a resin containing a charge transport material thereon. Any of the types can be used, such as a type in which a layer (CTL) is provided, and a type in which a composition in which a charge generating pigment is dispersed in the charge transport medium is provided on a conductive substrate.

The resin used for forming the photosensitive layer may be 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 laminated window photoreceptor, a charge-generating pigment such as a phthalocyanine pigment, perylene pigment, disazo pigment, trisazo pigment, or quinacridone pigment is applied on a conductive substrate. is provided as a vapor deposited layer or a resin pigment dispersion layer, and a charge transport layer containing a compound represented by the above-mentioned general formula is provided thereon. In this case, the specific compounds are 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 from the viewpoint of photo fatigue and ozone resistance, and when it is less than the above range, sufficient aggravation is not observed.

In addition, in the second type of photoreceptor described above, that is, one in which a charge-generating pigment is dispersed in a charge transport medium, the amount of binder resin is 100 to 100, and the charge-generating pigment is 5 to 100, preferably 10 to 50. 40 to 1 part by weight of the specific compound
They are used by dispersing or dissolving them in an amount of 50 parts by weight, preferably 70 to 100 parts by weight.

The specific compound used in the present invention is represented by the above-mentioned general formula, and includes, for example, a compound having the following structural formula. Among these, especially No, 2.3, 5゜6.1
4.15 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, 2.4.5-)riaminophenylimidazole, 2,5. -bis(4-diethylaminophenyl)
-1,3,4-triazole, 1-phenyl-3-(4
-diethylaminostyryl'')-5-(4-diethylaminophenyl)-2-pyrazoline, p-diethylaminobenzaldehyde-(diphenylhydrazone), and examples of suitable electron transport materials include 2-nitro-9-
Fluorenone, 2゜7-sinitro 9-fluorenone,
2.4.7-dolinitro-9-fluorenone, 2,4.
These include 5°7-tetranitro-9-fluorenone, 2-nitrobenzothiophene, 2.4.8-)linitrothioxanthone, dinitroanthracene, dinitroacridine, dinitroanthraquinone, and the like.

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 2.
．． 0 μm, CTL is 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 carrying out the photoreceptor of the present invention, it is better to use the first type, that is, a functionally separated photoreceptor consisting of two layers of CGL and CTL, since higher sensitivity can be obtained. desirable.

(Example 1) A cyclohexanone solution of metal-free phthalocyanine (weight ratio 2/75) was dispersed for 3 minutes using an ultrasonic disperser. An equal amount of a polyester resin tetrahydrofuran solution (weight ratio 2/75) was added to this dispersion, and ultrasonic dispersion was performed for 2 minutes to prepare a pigment dispersion.

This pigment dispersion was used to form a carrier generation layer (CGL: resin, pigment ratio 1/1) of 1.0 μm (film thickness when dry) on a conductive aluminum substrate using a bar coater.

Next, among the charge transport materials mentioned above, the NO12 compound is mixed with benzene in a weight ratio of 7:10 to the polycarbonate resin. This was dissolved to prepare a carrier transport layer (CTL) coating solution.

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

The thus obtained laminated photoreceptor was measured using a commercially available sensitivity measuring instrument 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 mm, and loaded into a commercially available limited photocopying machine (DC-5132 manufactured by Sanda Kogyo, modified to have a negative charging specification), and When 50 copies were made at high speed, clear copies without capri were continuously obtained. As a result, it was revealed that the laminated photoreceptor of the present invention has high sensitivity sufficient to withstand high-speed copying.

(Example 2) Regarding the master-like laminated photoconductor of Example 1, the pigment was changed from a phthalocyanine-based pigment to a disazo pigment (guiampure-based pigment).
2C, 1, 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 2 except that PVK was used instead of compound No. 2 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 16 Lux-sec From this, it was found that when PVK was used, the sensitivity was lower than when the charge transport material according to the present invention was used. .

(Example 3) 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. 1
Compound 2 70 parts by weight hyderidine chloride
Resin (Saran Resin manufactured by Dow Chemical) 100 parts by weight Tetrahydrofuran 1200 parts by weight The above formulation was placed in a stainless steel ball mill and dispersed for 24 hours to obtain a uniform coating solution. Next, a photoreceptor was prepared by applying the above coating solution onto an aluminum plate having a thickness of 80 μm using a doctor blade so as to have a thickness of 7 μm (when dry).

When I created a half-reduced exposure using EPA (STATU mode) in the same manner as in Example 1, it was 8°3 Lux-s.
It was found that it has a high sensitivity of EC.

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-111 manufactured by Sanda Kogyo, modified to have a negative charging specification) and copies were made at a speed of 11/min, clear copies with no capri were obtained. .

Takega 4 Mukuno\ Sankaku Kogyo Co., Ltd. Procedural Amendment (Method) % Formula % 2. Name of the invention Electrophotographic photoreceptor 3. Relationship with the person making the amendment Patent applicant address 1 Tamatsukuri, Higashi-ku, Osaka 540 Chome 2-28 Showa 6
July 28, 2017 (shipment date) 5. Column 6 of the detailed description of the invention in the specification subject to amendment, contents of the amendment 1) Replace page 6 of the specification with a separate sheet.

Claims (7)

[Claims] (1) As a charge transport material, there are the following general formulas ▲ mathematical formulas, chemical formulas, tables, etc. ▼ In the formula, n is an integer of 1 or 2; Ar_1 to Ar_4 represent substituted or unsubstituted phenyl groups, and the substituents are 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 4 to 100 parts by weight.
The photoreceptor according to claim 2, wherein the photoreceptor is contained in an amount of 0 to 150 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.