JPS60263944A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve durability and to prevent disturbance of picture image as well by incorporating a specified fluorine-contg. oligomer in a photosensitive layer provided on an electroconductive substrate. CONSTITUTION:A fluorine-contg. oligomer having 2,000-10,000 number average mol.wt. and expressed by the formula I or II (wherein R and R' are H, alkyl, aralkyl, aryl; n is 4-20; m is an integer) is allowed to contain in a photosensitive layer provided on an electroconductive substrate. Such oligomer is incorporated in the uppermost layer in a function separating type photosensitive body, but in a photosensitive layer in a single layer type photosensitive body. Preferred amt. of the oligomer to be used is 0.3-5wt% basing on the amt. of the binder resin. By this method, a photosensitive layer having superior moisture resistance, antifouling property, and wearing resistance is obtd. Particularly, a photosensitive body having superior durability to disturbance of picture image is obtd.

Description

[Detailed description of the invention] The present invention relates to an electrophotographic photoreceptor.

Inorganic photoconductive materials such as selenium, cadmium sulfide, and zinc oxide have conventionally been used as photoconductive materials for electrophotographic photoreceptors.

-Organic photoconductive materials such as polyhexyl, polyhinyl, rubazole, oxadiazole, and phthalocyanine have the advantage of being non-polluting and highly productive compared to inorganic photoconductive materials, but their sensitivity is low and it is difficult to put them into practical use. Ta. For this reason, several sensitization methods have been proposed. Among these, it is known that an effective method is to use a functionally separated photoreceptor in which a charge generation layer and a charge transport layer are laminated.

By the way, it goes without saying that electrophotographic photoreceptors are required to have predetermined sensitivity, electrical properties, and optical properties depending on the electrophotographic process to which they are applied. In particular, in the case of photoconductors that can be used repeatedly, electrical and mechanical external forces such as corona charging, toner development, transfer to paper, and cleaning processes are directly applied to the surface layer of the photoconductor.
Durability against them is required.

Specifically, there is a need for durability against decreased sensitivity and potential, increased residual potential due to deterioration due to ozone generated during corona charging, and surface abrasion and scratches caused by rubbing.

On the other hand, the moisture resistance of the photoreceptor is also an important property.

Even if a photoreceptor has excellent electrophotographic properties at low humidity, it is difficult to obtain stable and clear images with a photoreceptor whose surface potential decreases significantly under high humidity. Also,
In the electrophotographic process that involves transfer, the photoreceptor is usually
Since the photoreceptor is used repeatedly, its moisture resistance often deteriorates due to charging deterioration of the photoreceptor. This reduction in moisture resistance can be alleviated to some extent by heating the photoconductor with a heater and dehumidifying it, but this increases costs because the heater must be operated in the field. It is something.

Furthermore, when cleaning, methods that use blades place more stress on the photoreceptor surface, resulting in problems such as paper dust adhesion to the photoreceptor, material deterioration due to corona charging, and lower resistance of the photoreceptor surface in high humidity. Under certain conditions, a phenomenon often occurs in which the latent image flows in the direction of the blade's rubbing, and when it becomes visible, the image appears to have flowed (hereinafter referred to as "image 7X passing").

An object of the present invention is to solve the above-mentioned problems and provide an electrophotographic photoreceptor having excellent durability. It is an object of the present invention to provide an electrophotographic photoreceptor that has an effect of reducing image deletion in particular.

The object of the present invention is that the photosensitive layer provided on the conductive support has a structure represented by the general formula (1) or (2), and the number average molecular ψ is 2000 to 10000. This is achieved by using an electron)' true photoreceptor containing a fluorine-based oligomer in the range of .

-General Formula Here, R and R' represent a hydrogen atom, an alkyl group, an aralkyl group, or an aryl group, and the alkyl group may be substituted with, for example, a halogen atom, an alkoxy group, a dialkylamino group, or the like.

Further, the aralkyl group and acrylic group may be substituted with, for example, a halogen atom, an alkyl group, an alkoxy group, a dialkylamine group, or the like.

m and n are integers, and n is a number from 4 to 20.

When the number average molecular weight of the fluorine-based oligomer contained in the photosensitive layer is less than 2,000, the effect on image deletion is somewhat more effective than when no fluorine-based oligomer is added, but the effect is not sustainable. Furthermore, if the number average molecular weight is greater than 10,000, the compatibility with the binder resin constituting the photosensitive layer will deteriorate, making it difficult to form a uniform photosensitive layer.

The fluorine-based oligomer of the present invention is contained in the top layer of a functionally separated photoreceptor, and in the layer of a single-layer photoreceptor, thereby providing excellent moisture resistance, stain resistance, and abrasion resistance. A photosensitive layer can be obtained.

The added amount is desirably 0.3 wt% to 5 wt%, more preferably 0.5 wt% to 2 wt%, based on the solid content of the fluorine-based oligomer-containing layer. If the amount of the fluorine-based oligomer added is less than 0.3 w%, the effect will be small, and if it is more than 5 wt%, the surface hardness may decrease or the coating may become unreliable.

The fluorine-based oligomer used in the present invention can be synthesized by conventional methods. Thousands of Y-stars of fluorine-based oligomers were measured by GPC.

A specific explanation of the fluorine-based oligomer used in the present invention is as follows, for example.

(1) CtOF19-CONH-f'-CH2CH2
0-)-HH3 (3) C3F17-CONH-(-CH2CH20→
-ct-t3CH2CH3 H3 (10) Cl2F23-CONH-(=CI(2cH
20+-H When producing the electrophotographic photoreceptor of the present invention, a cylindrical cylinder or film made of metal such as aluminum or stainless steel, paper, or plastic is used as the substrate. A subbing layer (adhesive layer) having a barrier function and a subbing function can be provided on these substrates. The undercoat layer improves adhesion of the photosensitive layer, improves coating properties, protects the substrate, covers defects on the substrate, improves charge injection from the substrate,
It is formed to protect the photosensitive layer from electrical breakdown. Materials for the middle layer F include polyvinyl alcohol, poly-N-vinylimidasole, polyethylene oxide,
Ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, casein, polyamide, copolymerized nylon, glue, gelatin, and the like are known. These are each dissolved in a suitable solvent and applied to the 3i body. The film thickness is about 0.2 to 2 l.

In the functionally separated photoreceptor, charge-generating substances such as selenium-tellurium, pyrylium, thiopyrylium dyes 4, phthalocyanine pigments, anthanthrone pigments, dibenzpyrenequinone pigments, pyranthrone pigments, tris-aso pigments, disara pigments, aso-pigments, Indigo pigments, quinacridone pigments, asymmetric chimesyanine, chimesyanine, or amorphous silicon described in JP-A-54-143645 can be used.

In addition, examples of the charge transport substance include pyrene, N-ethylcarbazole, N-isopropylcarbazole, N-methyl-N-phenylhydrazino-3-methylidene-9-ethylgar8azole, N,N-diphenylhydrazino-3 −
Methylidene-9-ethylcarbazole, N,N-diphenylhydrazino-3-methylidene-10-ethidylphenothiazine, N,N-%, phenylhydrazino 3-methylidene-10-ethylphenoxazine, P-diethylaminobenzaldehyde N-N, N-diphenylhydrazaldehyde, P-diethylaminobenzaldehyde N-α-naphthyl-N-phenylhydrazino, P-pyrrolisinhenzaldehyde I.~N,
hydrazones such as N-diphenylhytoranane, 1,3.3-trimethylindolenine-ω-aldehy+N,N-diphenylhydrazone, P-diethylbenzaldehyde-3-methylhenzthiazolinone-2-hydrazone; 2,5-his(p-diethylaminophenyl)-1,
3,4-oxacyazole, 1-phenyl-3-(P-
diethylaminostyryl)-5-(P-diethylaminophenyl)pyrazoline, 1-[quinolyl(2))-3
-(P-diethylaminostyryl)-5-(P-diethylaminophenyl)pyrazoline, ■-[pyridyl (2)
)-3-(P-diethylaminostyryl)-5-(P-
diethylaminophenyl)pyrazoline, 1-[6-medoxyhylinyl(2))-3-(P-diethylaminostyryl)-5i(P-diethylaminophenyl)pyrazoline, 1-[pyridyl(3)]-3-( P-diethylaminostyryl)-5-(P-diethylaminophenyl)
Hilazoline, ■-[Lepidyl (2))-3-(P-diethylaminostyl)-5-(P-diethylaminophenyl)Hilazoline, 1-[Pyridyl (2))-3-(P-
diethylaminostyryl)-4-methyl-5=(P-diethylaminophenyl)pyrazoline, 1-[pyridyl-2))-3-'(α-methyl-P-diethylaminostyryl)-5-(P-diethylaminophenyl) Pyrazoline, l-phenyl-3-(P-diethylaminostyryl)-4-methyl-5-(P-diethylaminophenyl)hilazoline, ■-phenyl'-3-(α-benzyl-P-diethylaminostyryl)-5-( P-diethylaminophenyl)pyrazoline, spiropyratulin and other pyrazolines, 2-(P-diethylaminostyryl)-
Oxazole compounds such as 6-diethylamide/benzoxazole, 2-(P-diethylaminophenyl)-4-(P-dimethylaminophenyl)-5-(2-chlorophenyl)oxazole, 2-(P-diethylaminostyryl)- Thiazole compounds such as 6-diethylamino/benzothiazole, bis(4-diethylamino-2-
triarylmethane compounds such as (methylphenyl)-phenylmethane, 1,1-bis(4-N,N-diethylamine-2-methylphenyl)hebutane, 1,1,2.2
-Tetrakis-(4-N.

Polyarylalkanes such as N-dimethylamino-2-methylphenyl)ethane and the like can be used.

The charge generation layer contains 0.3 to 4 times the amount of the charge generation pigment described above, 4i! The 4'A agent resin and a solvent are well dispersed using a homogenizer, an ultrasonic wave, a ball mill, a vibrating ball mill, a sand mill, an attritor, a roll mill, etc., and then coated and dried. Its thickness is O,1~1
It is about 1000 yen.

The charge transport layer is electrically connected to the underlying charge generation layer and has the function of receiving charge carriers injected from the charge generation layer in the presence of an electric field and transporting these charge carriers to the surface. There is. At this time, this charge transport layer may be laminated on or under the charge generation layer. However, the charge transport layer
It is desirable that it be laminated on the second layer of the charge generation layer. Since this charge transport layer has a limit in its ability to transport electrical carriers, it cannot be made thicker than necessary.

Generally it is 5 microns to 30 microns, with a preferred range of 8 microns to 20 microns.

The organic solvent used when forming such a charge transport layer is
It varies depending on the type of charge transport material used, and it is preferable to select one that does not dissolve the charge generation layer or underlying layer. Specific organic solvents include alcohols such as methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, cyclohexanone, N,N-dimethylformamide, N,N
- Amides such as dimethylacetamide, sulfoxides such as dimethyl sulfoxide, ethers such as tetrahydrofuran, daoxane, ethylene glycol monomethyl ether, esters such as methyl acetate, ethyl acetate, chloroform, methylene chloride, dichloroethylene , carbon tetra11ide, aliphatic l\\logenated hydrocarbons such as trichloroethylene, or benzene, toluene, xylene, lidaroin,
Aromatic compounds such as monochlorobenzene and dichlorobenzene can be used.

Coating can be performed using coating methods such as dip coating, spray coating, spinner coating, single bead coating, Mayer-Par coating, plate coating, roller coating, and curtain coating.

For drying, it is preferable to dry to the touch at room temperature and then heat dry. Heat drying can be carried out at a temperature of 30° C. to 200° C. for a period of 5 minutes to 2 hours, either stationary or under ventilation.

The charge transport layer of the present invention may contain various additives in addition to the fluorosurfactant. Such additives include diphenyl, diphenyl chloride, 0-terphenyl, P-terphenyl, dibutyl phthalate, dimethyl glycol phthalate, dioctyl phthalate, triphenyl phosphoric acid, methylnaphthalene, benzophenone, chlorinated paraffin, dilaurylthiopropionate. ,3,5
-dinitrosalicylic acid and the like.

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

As is clear from the above description, since the electrophotographic photoreceptor of the present invention contains a fluorine-based oligomer in the photosensitive layer, it has excellent temperature resistance, stain resistance, and abrasion resistance. In particular, the electrophotographic photoreceptor of the present invention exhibits excellent durability against image deletion.

Next, the present invention will be explained according to examples.

Example 1 On a 60φ aluminum cylinder, 10 parts of polyamide resin (trade name Amilan CM-8000, manufactured by Toshi) (same as above) was dissolved in a mixed solvent of 70 parts of methyl alcohol and 20 parts of n-butyl alcohol. 10 after applying by dipping method.
It was dried at 0°C for 5 minutes to form a 0.5g drag layer.

Next, on top of this undercoat layer, a dispersion consisting of 4 parts of a disazo pigment having the following structure, 2 parts of butyral resin (trade name 5LECBM-2, manufactured by Miki Kagaku), and 100 parts of MEK was applied by dip coating. It was dried for 10 minutes to form a charge generation layer of 0.2p.

Further, on this charge generation layer, 10 parts of a hydralane compound having the following structure, 10 parts of polymethyl methacrylate resin (trade name: Dyanaru B R-88, manufactured by Mitsubishi Rayon), 80 parts of monochlorobenzene, and fluorine-based A coating solution consisting of 12 parts of Cl0F19-CONH- (CH2CH20-H (thousands average molecular weight Mn = 4000) shown as a specific example of the oligomer was applied by dip coating, and dried at 100°C for 60 minutes to form a full charge transport layer. formed.

The electrophotographic photoreceptor thus produced was -5,6k
V corona charger, exposure optical system with exposure amount of 151ux-see, developer, transfer charger, T! , using an electrophotographic copying machine equipped with an exposure optical system and a cleaner,
Temperature 23°C, humidity 60% and temperature 33°C9 humidity 90%
A continuous durability test was carried out under environmental conditions of 10% and the changes in dark potential (VD) and light potential (V'L) over time were measured.

Also, using this electrophotographic photoreceptor, the temperature was 33°C.

Continuous image printing durability test was conducted in an environment with 90% humidity.
The number of durable sheets until "image deletion" occurred was measured. The measurement results are shown in Table-1.

Comparative Example 1 An electrophotographic photoreceptor was produced in the same manner as in Example 1 except that the fluorine-based oligomer used in Example 1 was not added. The same measurements as in Example 1 were performed using this electrophotographic photoreceptor.

The measurement results are shown in Table-1.

Example 2 Cl0F1 used as the fluorine-based oligomer in Example 1
9-CONH-(-CH2CH20-+-H instead of polystyrene resin (trade name Dialex HF-) instead of polymethyl methacrylate resin of the charge transport layer.
An electrophotographic photoreceptor of the present invention was prepared and evaluated in exactly the same manner as in Example 1 except that 554 manufactured by Mitsubishi Monsanto Kasei was used.

The evaluation results are shown in Table-1.

Comparative Example 2 An electrophotographic photoreceptor was produced in the same manner as in Example 2 except that the fluorine-based oligomer used in Example 2 was not added. The same measurements as in Example 2 were performed using this electrophotographic photoreceptor. The measurement results are shown in Table-1.

Example 3 Cl0F1 used as the fluorine-based oligomer in Example 1
9-CONH-(-CH2CH20-)-H was used instead of 9-CONH-(-CH2CH20-)-H, and polycarbonate resin (trade name Panlite K
1300 (manufactured by Kijin Kasei), and a mixed solvent of 40 parts of monochlorobenzene and 40 parts of methylene chloride was used instead of 80 parts of the solvent Monochlorobenzene, but otherwise the electrophotographic photoreceptor of the present invention was prepared in exactly the same manner as in Example 1. was created and evaluated. The evaluation results are shown in Table-1.

Comparative Example 3 An electrophotographic photoreceptor was produced in the same manner as in Example 3 except that the fluorine-based oligomer used in Example 3 was not added. The same measurements as in Example 3 were performed using the electrophotographic photoreceptor. The measurement results are shown in Table-1.

Example 4 Cl0F1 used as the fluorine-based oligomer in Example 1
An electrophotographic photoreceptor of the present invention was prepared and evaluated in exactly the same manner as in Example 1 except that 9-CONH-←CH2CH2O→-H was used instead.

As an example of construction, I used Kamaki Masu.

Eight

Claims (1)

[Claims] The amount of the photosensitive layer provided on the conductive support is 200
An electrophotographic photoreceptor characterized by containing a fluorine-based oligomer in a range of 0 to 10,000. general formula