JPS59191060A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a sharp transferred image and to improve durability by incorporating a specific distyryl compd. in a photosensitive layer. CONSTITUTION:A photosensitive layer contg. the distyryl compd. expressed by the general formula ( I ) is provided as an electric charge conveying material on a conductive base. The electric charge generating material to be combined is exemplified by selenium, cadmium sulfide, amorphous silicon and various pigments.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor containing a specific disdyryl compound in its photosensitive layer.

PRIOR ART Conventionally, materials used as photoconductive materials for photoreceptors used in electrophotography include 1"! IIN materials such as selenium, sulfide, and zinc oxide. ``Photography'' generally means that a photoconductive photoreceptor is first charged in a dark place, for example by corona discharge, and then
Next, imagewise exposure is performed to selectively dissipate the charge only in the exposed area to obtain an electrostatic latent image, and this latent image area is composed of a coloring material such as a dye or pigment and a binder such as a polymeric substance. Test results? t1
There is an image forming method C in which both images are visualized by developing with Luna.

The basic characteristics required for this J, U41 electrophotographic method (13'' (3) It has scales that quickly dissipate charge when exposed to light.

Incidentally, it is a fact that each of the above-mentioned inorganic substances has many advantages, but also has various disadvantages. For example, selenium, which is currently widely used, does not fully satisfy the conditions (1) to (3) above, or the manufacturing conditions are difficult, the manufacturing cost is high, and it is not flexible. Hell! - It is difficult to process the
It also has some drawbacks, such as being sensitive to heat and mechanical shock, so care must be taken when handling it. Cadmium sulfide and zinc oxide are used as photoconductors instead of being dispersed in resin as a binder, but they have mechanical drawbacks such as smoothness, hardness, tensile strength, and resistance to scratching, so they are not used as they are. So why not use it repeatedly? (ki':ni'rX.

In recent years, photoreceptors for electrophotography using various organic materials have been developed to eliminate the drawbacks of these materials.
There are some things that have been proposed and offered to Tenkawa, for example:
One photosensitive film consisting of poly-N-vinylcarbazole and 2°4.7-t helofluorene-9-71 (US Pat. No. 3484237, July 4), poly-1\ 1-Vinyl calcazol is virylium! l
Sensitized by l'l dyes (T+11F)
118-25658 Publication vi), Yes) How many faces?
A photoreceptor (Japanese Patent Application Laid-Open No. 47-3754)
3), a photoreceptor whose component is a eutectic chain consisting of a dye (Japanese Unexamined Patent Publication No. 47-1073)
(described in Publication No. 5) 4I: There is. These photoreceptors have excellent characteristics and are thought to be practical and have a high price, or they are suitable for electrophotography and are suitable for photoreceptors (taking into consideration various requirements for this purpose). Then, the actual situation is whether these requirements are met within -1-minute or not.

However, the photoreceptors mentioned so far are all BL.
Although there are differences depending on the target or manufacturing method, generally speaking, good properties can be obtained by using a superior photoconductive material.

Purpose The purpose of the present invention is to eliminate the various drawbacks of the conventional photoreceptor mentioned above, and to meet the requirements of electrophotography. 1
The object of the present invention is to provide a photosensitive f-tree that satisfactorily satisfies the following. Another object of the present invention is to provide an electrophotographic photoreceptor that is easy to manufacture, relatively inexpensive, and has excellent durability.

Structure As a result of research and consideration on many photoconductive substances, the present inventor found that the following general formula (I) (where Ar is a substituted or unsubstituted naphthyl hydrogen atom, an alkyl group, an alkoxy group, an alkylene dihydrogen atom) ΔGish group, halogen atom or F
Muff/i expressed as -N? A-substituted amino group (in the formula \R) R7c15 and R3 represent an alkyl group, a substituted or unsubstituted aralkyl group, or a substituted or unsubstituted aryl group), and ■[ is an integer of 1.2 or 3; Yes, m
When is 2 or 3, R1 may be the same or different bases. n represents an integer of 2 or 3. ) It has been found that the distyryl compound represented by the following formula is effective as a photoconductive material for an electrophotographic photoreceptor.

Here, the substituent group in the naphthyl group of Ar is an alkyl group, an alkoxy group, a halogen atom, a substituted amino group, etc. ] Examples of the substituent include an alkyl group,
Al-'-)-2, thioalkoxy group, thiophenoxy group, halogen atom, dialkylamine group, 1~1''
Oxy group, small xy group, or its ester, acyl group, aryl group, aryloxy group, aralgyloxy and! , 1-lyhalomedyl group, nitro group, and cyano group. Furthermore, as will be clear from the description below, it has also been discovered that this distyryl compound can be combined with various materials to create photoreceptors with unexpected effects. The present invention was completed based on these findings.

That is, the present invention provides an IC electrophotographic photoreceptor in which a photosensitive layer is provided on a conductive support, and the photosensitive layer contains a distyryl compound represented by the above general formula (I). That is.

The invention will now be explained in more detail with reference to the accompanying drawings. 1 to 3 are three representative cross-sectional views of the photoreceptor according to the present invention, and the numbers assigned thereto are 1.
is a conductive support, 2.2-12'' is a photosensitive layer, 3 is a charge-generating substance, 4 is a charge-transporting medium or layer, and 5 is a charge-generating layer.

The distyryl compound represented by the general formula (I) used in the present invention has the following -IIWllQ(I[)liphenylphos small nium group or -P○(OR)z (here, the scale indicates a lower alkyl group)
A phenyl derivative represented by 1 which is dinonorkyl phosphite represented by 1 and the following general formula (I[)A1
40 days - CH) tc White O... (III) V In the formula, △r is the same as the general formula (I>, and is an integer of O or 1. React with an aldehyde compound represented by 1 You can get it by letting it happen.

Specific examples of the distyryl compound represented by the general formula (I) thus obtained are shown in Table 1 below.

282 (Ct-l:+)2 292 [Phase]-N (G OCI-13) 2302
(Feather N-+@C21-15) A specific example of 2CH3 production is as follows.

Production Example 1 Diethyl trans-cinnamylphosphonate 5.09 a
(0.02 mol) and 5.47 g (0.02 mol) of 4-N,N-diphenylaminobenz'aldehyde with N,
Dissolve N-dimethylformamide at 40 m℃ and add 28% sodium methoxide solution in methyl alcohol to this solution.
．． 63 g was added dropwise over 40 minutes at 27-35°C.

After the addition, the mixture was stirred at room temperature for 3 hours, diluted with 60 nu of methanol, and the crystals were collected by filtration, washed with water, and dried to obtain 6.200 yellow crystals (yield: 83.0%). Melting point is 15
The temperature was 7.5-159.0°C.

Next, it was recrystallized from a mixed solvent of dioxane-ethanol to obtain 1-phenyl-4-(4-N,N
A pure product of -diphenylaminophenyl)-1,3-butadiene was obtained. The melting point was 158.5-160.5°C. (Exemplary Compound N O, 27 in Table 1) The photoreceptor of the present invention contains one or more of the above-mentioned distyryl compounds in the photosensitive layer. Figures 1 and 2
It can be used as shown in FIG.

The photoreceptor shown in FIG. 1 has a photosensitive layer 2 comprising a distyryl compound, a sensitizing dye, and a binder (binder resin) on a conductive support 1. The photoreceptor shown in FIG. The distyryl compound here acts as a photoconductive substance, and the generation and transfer of charge carriers necessary for light attenuation take place via the distyryl compound. However, distyryl compounds have almost no absorption in the visible region of light, so in order to form images with visible light, it is necessary to sensitize them by adding a sensitizing dye that absorbs in the visible region. be.

The photoreceptor shown in FIG. 2 is provided with a photosensitive layer 2 on a conductive support 1, in which a charge generating substance 3 is dispersed in a charge transporting medium 4 made of a distyryl compound and a binder. . The distyryl compound here forms a charge transport medium 4 together with a binder (or a binder and a plasticizer), and a charge generating substance 3 (a charge generating substance such as an inorganic or organic pigment) generates charge carriers. . In this case, the charge transport medium 4 is mainly responsible for receiving charge carriers generated by the charge generating substance 3 and transporting them. The basic condition for this photoreceptor is that the absorption wavelength regions of the charge generating substance and the distyryl compound do not overlap with each other, mainly in the visible region. This is because in order to efficiently generate charge carriers in the charge generation material 3, it is necessary to transmit light to the surface of the charge generation material.

The distyryl compound represented by the general formula (I) has almost no absorption in the visible region, generally absorbs light in the visible region, and is particularly effective as a charge transport material when combined with a charge generating material 3 that generates charge carriers. Its characteristic is how it works.

The photoreceptor shown in FIG. 3 has a photosensitive layer consisting of a conductive support 1, a charge generation layer 5 mainly composed of a charge generation substance 3, and a charge transport layer 4 containing a distyryl compound. In this photoreceptor, light transmitted through the charge transport layer 4 reaches the charge generation layer 5, and charge carriers are generated in that region. The charge carriers are injected and transported by the charge generation material 3, which generates the charge carriers necessary for light attenuation, and transports the charge carriers by the charge transport layer 4 (mainly The mechanism is similar to that described for the photoreceptor shown in FIG.

In order to actually produce the photoreceptor of the present invention, as shown in FIG. 1, one or more distyryl compounds are dissolved in a solution containing a binder, and then added Prepare a liquid containing an infectious agent and apply it on the conductive support 1.
The photosensitive layer 2 may be formed by drying.

The thickness of the photosensitive layer 2 is 3 to 50 μnl, preferably 5 to 2
0 μm is appropriate. The amount of the distyryl compound in the photosensitive layer 2 is 30 to 70% by weight, preferably about 50% by weight, and the amount of the sensitizing dye in the photosensitive layer 2 is 0.1 to 70% by weight.
5% by weight, preferably 0.5 to 3% by weight. The sensitizers include Brilliant Green, Bik1 Helia Blue B1 Methyl Violet, Crystal Violet,
Triarylmethane dyes such as Acid Violet 6B, Rhodamine B, Rhodamine 6G.

Rhodamine G Extra, Eosin S, Erythrosin,
Rose Bengal, xanthine dyes such as fluorescein, thiazine dyes such as methylene blue, cyanine dyes such as cyanine, 2,6-diphenyl-4-(N,
N-dimethylaminophenyl) thiapyrylium verchlorate, benzobyrylium salt (Special Publication No. 1982-25658
Examples include biryllium dyes such as those described in Japanese Patent Publication No.

Note that these sensitizing agents may be used alone or in combination of two or more.

In addition, in order to produce the photoreceptor shown in FIG. 2, fine particles of the charge generating substance 3 are dispersed in a solution containing one or more distyryl compounds and a binder, and the fine particles are dispersed on a conductive support. The photosensitive layer 2' can be formed by coating and drying the photosensitive layer 2' on the photosensitive layer 1.

The thickness of the photosensitive layer 2- is 3 to 50 μm, preferably 5 to 20 μm.
μm is appropriate. The amount of the distyryl compound in the photosensitive layer 2- is 10 to 95% by weight, preferably 30 to 90% by weight, and the amount of the charge generating substance 3 in the photosensitive layer 2' is preferably 0.1 to 50% by weight. is 1 to 20% by weight.

Examples of the charge generating substance 3 include inorganic pigments such as selenium, selenium-tellurium, cadmium sulfide, cadmium-selenium sulfide, and α-silicon; examples of organic pigments include CI Pigmen 1 to Blue 25 (color index CI
21180), CI Pigment Red 41 (
CI 21200), Sea Eye Acid Red 52
(CI 45100), CI Basic Red 3 (CI 45240), azo pigment having a carbazole skeleton (described in JP-A-53-95033)
, an azo pigment having examples of disdylylbenzene (Unexamined Japanese Patent Publication No. 5
3133445), an azo pigment having a triphenylamine skeleton (described in Japanese Patent Publication No. 53-132347), an azo pigment having a dibenzothiophene skeleton (described in Japanese Patent Application Publication No. 54-21728), Azo pigment with oxadiazole case (Japanese Patent Application Laid-Open No. 54-12742
Distyryl oxadi Azo pigments having an azole skeleton (described in JP-A-54-2129), azo pigments having a distyrylno J rubazole case (described in JP-A-54-2129),
Azo pigments such as C.I. Pigment Blue 16 (CI74100); indigo pigments such as C.I. Rose 1 to Brown 5 (CI 73410) and C.I. Battai (CI 73030); Pigments, perylene pigments such as Argo Scarlet B (manufactured by Bayer) and Indus Thread Scarlet R (manufactured by Bayer). Note that these charge generating substances may be used alone or in combination of two or more.

Furthermore, in order to produce the photoreceptor shown in FIG. 3, the charge generating substance 3 is vacuum-deposited on the conductive support 1, or fine particles of the charge generating substance 3 are deposited in a suitable solvent in which a binder is dissolved if necessary. Apply the dispersion liquid dispersed in it, dry it and cover it,
Furthermore, if necessary, surface finishing and film thickness adjustment are performed by a method such as puff polishing to form a charge generation layer 5, and a solution containing one or more distyryl compounds and a binder is applied thereon. The charge transport layer 4 may be formed by coating and drying. The charge generating material 3 used here to form the charge generating layer 5 is the same as that used in the description of the photosensitive layer 2- above.

The thickness of the charge generation layer 5 is 5 μm or less, preferably 2 μm or less, and the thickness of the charge transport layer 4 is appropriately 3-5 μm, preferably 5 to 20 μm.

If the charge generation layer 5 is of a type in which fine particles of the charge generation substance 3 are dispersed in a binder, the proportion of the fine particles of the charge generation substance 'Q3 in the charge generation layer 5 is 10 to 95% by weight.
, preferably about 50 to 90% by weight. The amount of the distyryl compound in the charge transport layer 4 is 10 to 95% by weight, preferably 30 to 90% by weight.

In the production of these photoreceptors, a metal plate such as aluminum, a gold R foil, a plastic film on which a metal such as aluminum is vapor-deposited, or paper subjected to conductive treatment is used as the conductive support 1. In addition, as a binder, condensation resins such as polyamide, polyurethane, polyester, Epoquin resin, polyketone, polycarbonate, etc., and vinyl such as polyvinyl carbon, polybrene, poly-N-vinylcarbazolecrylamide, etc. Polymers are used, but any insulating and adhesive resin can be used.

A plasticizer may be added to the binder if necessary, and examples of such plasticizers include halogenated paraffin, polychlorinated hyphenyl, dimethylnaphthalene, and dibutyl phthalate.

Furthermore, in the photoreceptor obtained as described above, an adhesive layer or a barrier layer can be provided between the conductive support and the photosensitive layer, if necessary. The material used for these layers is polyamide, nitrocellulose, aluminum oxide, etc., and the film thickness is preferably 1 μm or less.

To make a copy using the photoreceptor of the present invention, the photoreceptor surface is charged and exposed, then developed and, if necessary, transferred to paper or the like. The photoreceptor of the present invention has excellent advantages such as high sensitivity and flexibility.

Examples are shown below. In the following examples, all parts are by weight.

Example 1 7 6 parts of Diane Blue (CI Pigment Blue 25, CI 21180) as a charge generating substance, polyester resin (Vylon 200, manufactured by Toyobo Co., Ltd.)
1,260 parts of a 2% tetrahydrone furan solution and 3,700 parts of tetrahydrofuran were pulverized and mixed in a ball mill, and the resulting dispersion was applied to the aluminum surface of an aluminum-deposited polynisdel base J using a doctor blade. Apply and dry naturally to a thickness of approx.
A charged dead layer with a diameter of 1 μm was formed.

On the other hand, as a charge transport substance, 2 parts of distyryl compound No. 27, polycarbonate resin (1300
．． 2 parts (manufactured by Teijin Ltd.) and 1 part of tetrahydrofuran
After mixing and dissolving 6 parts to form a solution, this was applied onto the charge generation layer using a doctor blade and heated at 80°C for 2 hours.
minutes, then dried at 105℃ for 5 minutes to a thickness of approximately 20 tons.
Examples 2 to 27 in which photoreceptor N011 was prepared by forming a charge transport layer of 1m Charge generating substance and charge transporting substance (distyryl compound)
Photoreceptors Nos. 082 to 27 were prepared in the same manner as in Example 1 except that the photoreceptors were replaced with those shown in Table 2.

Example 2ε3 On an aluminum plate having a thickness of about 300 μm, selenium was vacuum-deposited to a thickness of about 1 μm to form a charge generation layer. Next, 2 parts of cisdyryl compound No. 27, polyester resin (Polyester Adhesive 4900 manufactured by DuPont)
0) and 45 parts of tetrahydrofuran were mixed and dissolved to prepare a charge transport layer forming liquid, and this was applied to the above charge generation layer (selenium vapor deposited layer) using a doctor blade, and after air drying, Dry under reduced IL to a thickness of approximately 1
A charge transport layer of 0 μm is formed to form a photoreceptor N of the present invention.
O.28 was obtained.

Example 27 A charge generation layer was formed using a perylene pigment instead of selenium (however, the thickness was about 0.3 μm), and a distyryl compound was used instead of No. 27, and NO was used instead of 27.
Photoreceptor No. 29 was prepared in exactly the same manner as in Example 28 except for the IC.

Example 30 A mixture of 1 part of Diane Blue (same as used in Example 1) and 158 parts of tetrahydrofuran was pulverized and mixed in a ball mill. A photosensitive layer forming solution obtained by adding 18 parts of Polyester Athesive 49000 (manufactured by DuPont) and roughly mixing was applied onto an aluminum-deposited polyester film using a doctor blade, and dried at 100°C for 30 minutes. Approximately 16μ thick
Photoreceptor No. 3 of the present invention was formed by forming a photoreceptor layer of m.
0 was created.

Photoreceptors Nos. 1 to 30 thus produced were tested using a commercially available electrostatic copying paper tester (KK Ill ml).
After performing corona discharge of 16KV or +6KV for 20 seconds using a 71M Isosei Dojo 5P428 model to charge -C, it was left in a dark place for 20 seconds, and the surface potential Vpo at that time was
(Volts) were set at tl and lI, and then irradiated with tungsden lamp light so that the illuminance of the photoreceptor surface became 4.5 lux, and the time (seconds) was set until the surface potential reached ■pO of 172. Find, exposure ff1E1/2 (lux seconds)
was calculated. The results are shown in Table-3.

Further, each of the above-mentioned photoreceptors was charged with a commercially available electrophotographic copying machine, and then light was irradiated through the original image to form an electrostatic latent image, which was developed using a dry developer. When the resulting image (toner image (GL)) was electrostatically transferred onto plain paper and fixed, a clear transferred image was obtained.A similarly clear transferred image was obtained when 'C wet type developer was used as the developer. 7j is obtained.

Table 3 Photoconductor VIIIOEL/2 No. (volt) (lux/second) 1
-1100 1.62 - 9
70 1.53 -1200
1.14 -1150 2.25
-800 0.8 6 -1200 '1.07
-790 2.18 -950
1.39 -52o 1.21
0 -1135 1.111 -
750 0.712 -1380
1.213 -60'OO, 8 14-11401, 0 15-9801, 1 16-13001, 2 17 - 940 1.0+
8 -1390 1.249
-990 1.120
-1490 1.421
-1030 1.322
-1140 1.223
-920 0.824 -
830 1.225 -68
0 0.926 -1180
1.927 ~1090
1.328 -1200
2.129 -1290
3.830 → -12001,8 Effect As described above, the photoreceptor of the present invention has the general formula (I)
By using the disdyryl compound represented by the above, the conditions required for a photoreceptor are fully satisfied and clear images are formed.

[Brief explanation of the drawing]

FIGS. 1, 2, and 3 section 1 indicate l! in the vertical direction of the electrophotographic photoreceptor according to the present invention. It is a cross-sectional view of the rx human. 1... Conductive support 2.2-12"... Photosensitive layer 3... Charge generating material 4... Charge transporting medium or charge transporting layer 5... Pa City I 1b Oxygen layer Patent Applicant Stock Meeting 1 - Rico - Agent Patent Attorney Hidetake Komatsu Figure 1 Figure 2 Figure 3 Procedural amendment 1, Indication of case Patent application dated April 14, 1981 (1) 2, Title of invention Electronic photograph Photoreceptor 3, Relationship with the case of the person making the amendment Name of patent applicant (674) Ricoh Co., Ltd. 5, Date of amendment order (spontaneous) 6. Subject of amendment Column for detailed explanation of the invention in the specification. 7. Contents of the amendments are as attached. (Attachment) (1) [Photoconductor No. 1 to No. 0] in Table 2 on page 28 of the specification
The structural formula of 02 is corrected as follows. Table-2

Claims (1)

[Claims] 1. A photosensitive material for electrophotography, comprising a photosensitive layer containing at least one disdyryl compound represented by the following general formula (I>) as an active ingredient on a conductive support. (In the formula, Ar is a substituted or unsubstituted naph-dylkylene diogish group, a halogen atom, or 2/3 R2 and R3 are an alkyl group, a substituted or unsubstituted aralkyl group, or a substituted or unsubstituted aryl group. )
, ■ is an integer of 1.2 or 3, and nl is 2
Or when it is 3, [1 is the same base but different bases are b] indicates an integer of n or 3. )