JPH01230060A - Photosensitive body - Google Patents

Abstract

PURPOSE:To provide excellent carrier generating power and high sensitivity and small residual potential and to improve the durability against repetitive use by providing a photosensitive layer contg. a specific squarium compd. on a conductive base. CONSTITUTION:The photosensitive layer contg. the squarium compd. expressed by formula I is provided on the conductive base. In formula I, R<3>-R<6> denote a hydrogen atom., alkyl group (preferably a methyl group) or halogen atom. (preferably a fluorine atom., chlorine atom., bromine amin); R<9> denotes a substd. or unsubstd. group and is exemplified by, for example, an alkoxy group, halogen group, cyano group, nitro group, hydroxyl group, ester group, acyl group, dialkyl amino group, diaralkylamino group, diarylamino group, aryl group, heterocyclic group, etc. The photosensitive body which has the electrostatic charge characteristic, sensitivity characteristic and image forming characteristic, is less fatigued and deteriorated even after repetitive use and has the excellent durability is thereby obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a photoreceptor, and more particularly to a novel photoreceptor having a photosensitive layer containing a specific squareium compound.

[Prior Art] Conventionally, as electrophotographic photoreceptors, inorganic photoreceptors having a photosensitive layer mainly composed of an inorganic photoconductive compound such as relene, zinc oxide, cadmium sulfide, silicon, etc. have been widely used. However, these are not necessarily satisfactory in terms of sensitivity, thermal stability, moisture resistance, durability, manufacturing cost, etc. For example, when selenium crystallizes, its properties as a photoreceptor deteriorate, making it difficult to manufacture, and it becomes activated due to heat, fingerprints, etc., resulting in deterioration of its performance as a photoreceptor. In addition, for cadmium sulfide, moisture resistance vj durability,
Even zinc oxide has problems with durability, etc.

In order to overcome these drawbacks of non-d photoreceptors, research and development of organic photoreceptors having photoreceptors whose main components are various organic photoreceptors has been actively carried out in recent years11. For example, in Special Publication No. 1, Oct. 1970! > No. 6 (Yo).

There is a description of a 1-hole photoreceptor containing poly-N-vinylcarbazole and 2.4.7-i.linitro-9-fluorenone. However, this photoreceptor is not necessarily satisfactory in sensitivity and durability. In order to improve these drawbacks, attempts have been made to develop organic photoreceptors with higher performance by assigning carrier generation and carrier transport capabilities to different materials. Many studies have been conducted on such so-called function-separated type photoreceptors because each material can be selected from a wide range and a photoreceptor having arbitrary performance can be produced relatively easily.

[Problems to be Solved by the Invention] Many compounds have been proposed as carrier-generating substances in the functionally separated type photoreceptor as described above.

An example of using an undefeated compound as a carrier generating substance is, for example, amorphous selenium described in Japanese Patent Publication No. 4316198, which is used in combination with an organic photoconductive compound. The drawback that the generation layer is crystallized by heat and the 1'i properties as a photoreceptor deteriorates has not been improved.

In addition, many electrophotographic photoreceptors have been proposed that use pigments as chytria-generating substances. Typical examples include bisazo compounds (Electrophotography Society 59th Research Conference p. 179.1987), phthalocyanine compounds (
JP-A-6L-239248), azulenium compound (
Electrophotography Society 55th Research Conference p. 60, 1985
> , Squarium compound (JP-A-Sho G1-37846
) etc. However, these compounds are not necessarily satisfactory in terms of sensitivity, residual potential, or stability during repeated use, and
The selection range of carrier transporting substances is also limited, and the wide range of requirements of electronic copying processes cannot be fully satisfied.

Furthermore, in recent years, Arrayri "-1!-1" has been used as a light source for photoreceptors.
Gas lasers such as cm and Ne lasers and semiconductor lasers are beginning to be used. These lasers can be turned on and off in chronological order, and can be used as a light source for printers with image processing functions such as intelligent copiers and printers for output. It was visible in the U telescope at 1h. Among these, semiconductor lasers are attracting attention because their nature eliminates the need for electrical signal/optical signal conversion elements such as acoustic engineering elements, and they can be made smaller and lighter. However, this semiconductor laser has a low output compared to a gas laser, and the excavation wavelength is also a long wavelength (approximately 780 nm or more), so in conventional photoreceptors, the spectral sensitivity is often on the short wavelength side, and the sensitivity characteristics However, there was nothing that was practically satisfactory.

[Object of the Invention] An object of the present invention is to provide a photoreceptor containing a specific squareium compound having excellent carrier generation ability.

Another object of the present invention is to provide a photoreceptor with high sensitivity, low residual potential, and durability (7) whose characteristics do not change even after repeated use.

Still another object of the present invention is to provide a photoreceptor containing a squalium compound that can effectively act as a carrier generating substance even in combination with a wide variety of carrier transporting substances.

Still another object of the present invention is to provide a photoreceptor having sufficient practical sensitivity even to long wavelength light sources such as semiconductor lasers.

Further objects of the present invention will become clear from the description in the specification.

[Means for Solving the Problems] As a result of intensive research aimed at achieving one or more objects, the present inventors have found that a squareium compound represented by the following general formula [I] is We discovered that it can be used as an ingredient,
This completes the invention.

General formula [■] In the formula, RO, R1, and R2 are each a hydrogen atom, a halogen atom (preferably a fluorine atom), an alkyl group (preferably a methyl group), an alkoxyIt (n? or a methoxy group), and a water l ! i! 21 or N l-I Y. Y is -, C-R' or -8O2-R'' (R7 and R8 are alkyl groups each optionally having a substituent,
) represents a nyl group or a hydrogen atom. ), represents.

R3, R4, R5 and R6 are hydrogen atoms, alkyl groups (
(preferably a methyl group) or a halogen atom (preferably a fluorine atom, chlorine atom, or bromine atom). R
9 represents a substituted or non-substituted alkyl group. Examples of the substituent B of an alkyl group include an alkoxy group, a halogen atom, a cyan group, a nitro group, a hydroxyl group, an ester group, an acyl group, a dialkylamino group, a dialkylamino group, a diarylamino group, an aryl group, and a heterocyclic group. etc. can be mentioned.

Specific examples of the squalium compounds useful in the present invention are shown below, but the squalium compounds of the present invention are not limited thereto.

Both hands margin -1″・ 1-, knee.

The squalium compound of the present invention represented by the general formula [I] can be easily synthesized by the synthesis method described below.

(Synthesis Example 1) For the synthesis of compound -1 -1 As shown in the figure above, N-methylindoline S-124
,20(1,1(i xlO-!moj!) and Sufu I
7') Tuccinic acid 2 5.0(1(4,38xlo-2
mo1) into a 3001Q four-headed flask, and
Add Heptatool 2201Q and under reduced pressure (140mm1
Stir and reflux at 1 rJ±1010 ml. Remove water using the ester tube, and stop heating when about 1 cc of water has accumulated in the ester tube. It took about 30 hours. When the reaction solution has cooled to room temperature, the reduced pressure is released and the precipitated crystals are filtered using a Kiryama funnel. Wash 3 times with acetone, 3 times with hot water, and 2 times with MeOH. It was dried overnight at 70-80°C. 75 g (yield: 50%) of the target product -1 was obtained as green crystals. The following data confirmed the structure of K-1.

Visible absorption spectrum (in CH2CQ2) λmax = 6
45 nm Infrared absorption spectrum (in KBr) ν (= 0 = 1590 cm-' melting point (Japanese Pharmacopoeia Law Melting Point Training Method) 240''C In addition, this compound was dispersed in THF, and the dispersion was placed on a bed with a wire bar. When it was measured with a spectrophotometer, it showed the following transmission absorption.

Visible absorption spectrum (dispersion system) λll1aX = 820 nm The squareium compound of the present invention has excellent photoconductivity. It can be produced by providing a photosensitive layer in which the compound is dispersed in a binder, but among the photoconductivity of the squareium compound of the present invention, it can be used as a carrier-generating substance by taking advantage of its ability to generate carriers. Particularly excellent results can be obtained when a so-called functionally separated type photoreceptor is constructed by using a carrier transport substance that can effectively act in combination with the photoreceptor. Although the functional separation type photoreceptor may be of a dispersion type, it is more preferably a laminated type photoreceptor in which a carrier generation layer containing a carrier generation substance and a carrier transport layer containing a chitria transport substance are laminated.

When the squalium compound of the present invention is used as a carrier-generating substance, the carrier-transporting substance to be used in combination with it is an electron-accepting substance that easily transports electrons, such as 1-lini-1-rofluorenone or tetranitrofluorenone. In addition, polymers having a heterocyclic compound in the side chain such as poly-N-vinylcarbazole, 1-lyazole derivatives, oxadiazole derivatives, imidazole u4K, pyrazoline derivatives), polyarylalkane Transports holes such as M PJ derivatives, phenylenediamine derivatives, hydrazone conductors, amine-substituted carbon derivatives, triarylamine derivatives, carbazole derivatives, stilbene derivatives, phenothiazine y, 0 derivatives, azine derivatives, butadiene derivatives, Schiff base derivatives, etc. Examples include electron-donating substances that are easy to transport, but the carrier transporting substances used in the present invention are not limited to these.

Various types of photoreceptors are known, and the photoreceptor of the present invention can be used in any of them.

Usually, the configuration is as shown in FIGS. 1 to 6. Figures 1 and 2
In the figure, a photosensitive layer 4 consisting of a laminate of a carrier generation layer 2 containing the above-mentioned squalium compound as a main component and a carrier transport layer 3 containing a carrier transport substance as a main component is formed on a conductive support 1. establish. As shown in FIGS. 3 and 4, this photosensitive layer 4 consists of an intermediate layer 5 provided on a conductive support.
It may also be provided via When the photosensitive layer 4 has a two-layer structure as described above, a photosensitive member having the most excellent electrophotographic properties can be obtained. Further, in the present invention, as shown in FIGS. 5 and 6, the above-mentioned QV-R generation substance 7 and carrier transport substance are contained in the layer 6 in one molecule! The photosensitive layer 4 made of L-shaped layers may be provided directly on the conductive support 1 or via an intermediate layer 5.

The carrier generation layer 2 constituting the two-layered photosensitive layer 4 is applied directly to the conductive support 1 or -I:I- rear transport layer 3, or if necessary, an intermediate layer such as an adhesive layer or a barrier layer is applied. It can be formed by, for example, the following method (2).

M-1> A method of applying a solution in which a squalium compound is dissolved in a suitable solvent, or a solution in which a binding agent is added and mixed as necessary (57).

M-2) A method in which a squalium compound is made into fine particles in a dispersion medium using a ball mill, a homomixer, etc., and a binder is added as necessary to mix and disperse the resulting dispersion and then applied.

The solvent or dispersion medium used for forming the carrier generation layer includes n-butylamine, diethylamine, ethylenediamine, isopropanolamine, 1-liethanolamine, 1-lyethylenediamine, N,N-dimethylformamide, acetic acid -, methyl ethyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, 1,2-dichloroethane, 1,1.2-1~likuDloethane, 1,1.1-trichloroethane, trichloroethane, tetrahyloloecune, dichloromethane, Tetrahydrofuran, dioxane, methanol, ethanol, isopropanol, iW[l ethyl, butyl acetate,
Examples include dimethyl sulfoxide.

When using a binder in the carrier generation layer or carrier transport layer, any binder can be used, but it is preferable to use a film-forming polymer that is hydrophobic, has a high dielectric constant, and is electrically insulating. preferable. Examples of such high molecular weight polymers include the following:
It is not limited to these.

P-1) Polycarbonate P-2) Polyester P-3) Methacrylic resin P-4) Acrylic resin P-5) Polyvinyl chloride P-6) Polynylidene chloride P-7) Polystyrene P-8) Polyvinyl acetate-1 ~ P-9) Styrene-butadiene copolymer P-10) i2
Vinylidene dioxide-acrylonitrile copolymer P-11) Vinyl chloride-vinyl acetate copolymer P-1
2) Vinyl chloride-vinyl acetate-maleic anhydride copolymer P-13) Silicone resin P-14) Silicone-alkyd resin P-15) Phenol formaldehyde resin P-1
6> Sujirene-alkyd resin P-17) Poly-N-
Vinyl carbazole p-18) Polyvinyl butyral p-19) Polyvinyl formal p-20) Vinyl acetate resin p-21) Epoxy resin These binders can be used alone or in a mixture of two or more.

The thickness of the carrier before generation 2, which is formed like a mouth, is
It is preferable that it is 0.01μI11-20μm,
More preferably, it is 0.05 μm to 5 μl. Further, when the carrier generation layer or the photosensitive layer is a dispersion system, the potential of the squarium monomer is preferably 5 μm or less,
More preferably, it is 1 μm or less.

As a conductive layer, on the ig conductive support 1), a non-conductive compound such as acid, tin oxide, copper iodine, carbon, right-hand semiconductor, conductive material, engineered polymer, etc. It can be formed by dispersing an organic conductive compound in a binder or applying it as it is.

The Squarium 1H compound of the present invention can be subjected to various processes to improve its dispersibility from the viewpoint of powder and granule engineering. For example, wet granulation, spray drying,
Freeze drying, dry grinding, etc. can be used.

Further, by changing the crystal form, electrophotographic performance and dispersibility can be improved. For example, the crystal form may change depending on the method of dissolving with purulent amine and then neutralizing and precipitating with acid, or depending on pressure, temperature, etc.

The conductive support used in the photoreceptor of the present invention includes a metal plate including an alloy, a metal drum, or a conductive polymer such as aluminum, palladium, gold, etc., including a conductive compound such as indium oxide, or an alloy. Paper coated with a thin layer, vapor deposited or laminated to make it conductive;
Examples include Plus L Tsuku film.

For the intermediate layer such as the adhesive layer or barrier M, in addition to the polymer used as the binder, an organic polymer material such as polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, or aluminum oxide is used.

The photoreceptor of the present invention has the above-mentioned structure, and has the following characteristics, which are clear from the examples, such as J: sea urchin, charging characteristics,
It has poor sensitivity characteristics and image forming characteristics, and has excellent durability, with little fatigue deterioration even after repeated use.

[Implementation! 4] Hereinafter, the embodiments of the present invention will be specifically explained using Examples, but the embodiments of the present invention are not limited thereby.

(Example 1) In a 300-inch stainless steel pot, 0.75 g of polyvinyl butyl resin (trade name, XYHL), 1502 g of tetho-nohydrofuran, and Squarium compound [3-11
Add 150 IQ of Glass Peas.

Disperse with a sand grinder for 48 hours. After drying this dispersion on an aluminum vapor-deposited base, the film thickness is approximately 0.2μ.
Apply with a Y-V-bar so that the carrier generation is 1m (
CGL) was formed. Next, 7.5 liters of polycarbonate resin (trade name, Panlite), 50 n of ethylene chloride, and -14.0 Cl of IJ material transported by a manure carrier are mixed with a magnetic stirrer. This liquid was applied onto the CGL using an applicator so that the film thickness after drying was 20 μm to form a carrier transport ff1 (CTL).

After being placed in the oven and thoroughly dried, the electrophotographic performance was tested. In other words, 15. Electrostatic copying test equipment manufactured by Kawaguchi Electric was charged with 6KV of Lee for 5 seconds. Measure, then apply 14 lux of tungsten 8[1 gen lamb to one photosensitive layer QJ L, calculate the time until its surface potential becomes half of V^, and calculate the half-life exposure amount E + /
I asked for 2. As a result, VA -1200V, E 1/
2 = 2.51 ux-sec.

Next, the image margin characteristics and durability were tested using a Konica (Screw D printer (semiconductor laser with a light source of 790'r++++±10nn+). Good images were obtained in a test of printing up to 10,000 sheets. I was attacked.

Proceed to Example 2・10 In Example 1, the material (CGM) B-1 and the carrier width transfer material (CTMI) K-1 were changed as shown in Table 1 to prepare a photoreceptor 1r. The electrophotographic performance was evaluated in the same manner as in Xiamen 11. The results are shown in Table 1.

Table 1 CTM in Table 1 is not shown below.

-3 -4 -5 -9 -10 Implemented @11 In Example 1, CG t- and CT 1. A photoreceptor was prepared and tested in the same manner as in Example 1, except that the order of application of - was reversed. (However, the charging voltage was 46 KV.

) The result is V^=11! i0V, El/2 = 2.7
It was lux SQC. Moreover, the images of up to 10,000 pictures were good.

Examples 12 to 20 In Example 11, carrier-originated one-day shopping (CGM) B-
1 and 4t! Table 1
A photoreceptor was prepared with the following changes, and the electrophotographic performance was evaluated in the same manner as in Example 11. The results are shown in Table 2.

The following margins - Table 2 -11 -12 -13 -14 -15 -18 The squarium compound represented by the general formula [11] is used as the constituent photoconductive material. It has excellent electrophotographic properties such as sensitivity, residual potential, and charge retention, and also has excellent electrophotographic properties such as ff1 fatigue after repeated use. It has little deterioration, is stable against heat and light, and has sufficient sensitivity even in the long wavelength region of roughly 780 nm or more, and at the same time has sufficient sensitivity in the visible light region of 780 nm or less (with a highly usable photoreceptor). Be able to create it.

Further, by using the squalium compound of the present invention, a photoreceptor having sufficient sensitivity can be produced even when used in conjunction with a wide range of chyrelia transport products.

[Brief explanation of the drawing]

1 to 6 are sectional views showing examples of the practical structure of the photoreceptor of the present invention, and 1 to 7 in the figures represent the following, respectively. 1... Conductive support 2... Carrier generation layer 3... Carrier transport layer 4... Photosensitive layer 5... Intermediate layer 6... Layer containing carrier transport substance 7... Carrier generation material

Claims (3)

[Claims] (1) A photoreceptor comprising a photosensitive layer containing a squarium compound represented by the following general formula [I] on a conductive support. General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, R^0, R^1, and R^2 each represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxyl group, or NHY. . Y is ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or -SO_2-R^6 (R^7 and R^
8 represents an alkyl group, a phenyl group, or a hydrogen atom, each of which may have a substituent. ). R^3
, R^4, R^5 and R^6 represent a hydrogen atom, an alkyl group or a halogen atom. R^9 represents a substituted or unsubstituted alkyl group. ] (2) The photosensitive layer contains a carrier transporting substance and a carrier generating substance, and the carrier generating substance has the general formula [
A claim which is a squarium compound represented by
1) The photoreceptor described above. (3) Claim (1) or (2) wherein the photosensitive layer is constituted by a laminate of a carrier generation layer containing a carrier generation substance and a carrier transport layer containing a carrier transport substance.
) Photoreceptor described.