JPH04254862A - Electrophotographic photosensitive body and electrophotographic device and facsimile with electrophotographic photosensitive body - Google Patents

Abstract

PURPOSE:To obtain a photosensitive body with sufficient sensitivity in laser diode oscillation wave length area and stable electric potential in repeated use by providing a specified crystal type oxytitanium phthalocyanine as charge producing substance and providing a photosensitive layer in which a specified carbonyl compound is used as charge transport substance. CONSTITUTION:A crystal type oxytitanium phthalocyanine with strong peaks at Bragg angles 2theta+ or -0.2 deg. of 9.0 deg., 14.2 deg., 23.9 deg., and 27.1 deg. in a X-ray diffraction of CuKalpha is contained, and also at least one kind of carbonyl compounds shown in the formula is contained. In the formula, Ar through Ar4 represent aryl group which may have substitute, and R1 and R2 represent hydrogen atom or alkyl group.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to an electrophotographic photoreceptor, an electrophotographic device equipped with the electrophotographic photoreceptor, and a facsimile, and more particularly, the present invention relates to an electrophotographic photoreceptor, and more particularly, it has a photosensitive layer containing a specific charge-generating substance and a specific charge-transporting substance. The present invention relates to an electrophotographic photoreceptor, an electrophotographic apparatus equipped with the electrophotographic photoreceptor, and a facsimile.

0002

[Prior Art] Conventionally, electrophotographic photoreceptors include selenium,
Inorganic photoreceptors having photosensitive layers mainly composed of inorganic photoconductive substances such as cadmium sulfide and zinc oxide have been widely used. These materials are not necessarily satisfactory in terms of thermal stability, moisture resistance, durability, etc. In particular, selenium and cadmium sulfide have limitations in production and handling due to their toxicity.

On the other hand, organic photoreceptors having a photosensitive layer containing an organic photoconductive compound as a main component have many advantages such as compensating for the above-mentioned drawbacks of inorganic photoreceptors, and have attracted attention in recent years. As such an organic photoreceptor, poly-N-vinylcarbazo-
Photoconductive polymers typified by
Electrophotographic photoreceptors having a photosensitive layer mainly composed of a charge transfer complex formed with a Lewis acid such as 7-trinitro-9-fluorenone have already been put into practical use. However, this electrophotographic photoreceptor is not necessarily satisfactory in sensitivity and durability. Functionally separated electrophotographic photoreceptors, in which charge generation and charge transport functions are performed by separate materials, have brought about significant improvements in sensitivity and durability, which were considered to be shortcomings of conventional organic photoreceptors. Such a functionally separated electrophotographic photoreceptor has the advantage that there is a wide selection range of materials for each of charge-generating substances and charge-transporting substances, and an electrophotographic photoreceptor having arbitrary characteristics can be produced relatively easily. There is.

In recent years, the use of electrophotographic photoreceptors not only in copying machines but also in non-impact type printers applying electrophotographic technology has rapidly increased. These are mainly laser beam printers that use laser light as a light source, and a semiconductor laser is used as the light source from the viewpoint of cost and size of the device. The oscillation wavelength of the semiconductor lasers currently mainly used is 790±20nm.
Because of these long wavelengths, progress has been made in the development of electrophotographic photoreceptors that have sufficient sensitivity to these long wavelengths of light. Sensitivity on the long wavelength side varies depending on the type of charge-generating material, and many charge-generating materials are being studied. Typical charge generating materials include phthalocyanine pigments, azo pigments, cyanine pigments, azulene pigments, and squarylium dyes. On the other hand, as charge-generating materials sensitive to long wavelength light, metal phthalocyanines or metal-free phthalocyanines such as aluminum lophthalocyanine, chloroindium phthalocyanine, oxyvanadium phthalocyanine, chlorogallium phthalocyanine, magnesium phthalocyanine, and oxytitanium phthalocyanine have recently been developed. More and more research is being done. Among these, many phthalocyanine compounds are known to have polymorphisms; for example, metal-free phthalocyanine has α-type, β-type, γ-type, δ-type, ε-type, τ-type, χ-type, etc., and copper phthalocyanine has α-type, Types such as type, β type, γ type, δ type, and χ type are known. It is also known that differences in crystal form have a large effect on electrophotographic properties (sensitivity, potential stability during durability, etc.) and coating properties when made into a paint. Oxytitanium phthalocyanine, which is particularly sensitive to long-wavelength light, has polymorphisms like other phthalocyanines such as the above-mentioned metal-free phthalocyanine and copper phthalocyanine. For example, Japanese Patent Application Laid-Open No. 59-49544 (USP 4,4
44,861), JP-A-59-166959, JP-A-61-239248 (USP 4,728,5)
92), Japanese Unexamined Patent Publication No. 62-67094 (USP 4,6
64,997), JP-A-63-366, JP-A-6
Oxytitanium phthalocyanine having different crystal forms has been reported in JP-A No. 3-116158, JP-A-63-198067, and JP-A-64-17066. However, these oxytitanium phthalocyanines have several problems in actual use, such as insufficient sensitivity, poor potential stability during repeated use, poor charging ability, and image deterioration due to changes in the usage environment. ,
I still don't have anything that satisfies me. By the way, in general, in electrophotographic photoreceptors, a charge transporting material that is effective for a certain charge-generating substance is not necessarily effective for other charge-generating substances; A charge-generating substance that is effective against other charge-transporting substances may not necessarily be effective against other charge-transporting substances. That is, there is always a suitable combination of these charge-generating substances and charge-transporting substances that transfer charges. Inappropriate combinations may cause a number of problems such as a decrease in sensitivity and an increase in residual potential, deterioration in potential stability during repeated use, and a decrease in charging ability. Therefore, the combination of a charge-generating substance and a charge-transporting substance is extremely important, but there are no general rules and it is not easy to find a charge-transporting substance that is compatible with a specific charge-generating substance.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photoreceptor having sufficiently high sensitivity in the laser diode oscillation wavelength range, and which maintains a stable potential during repeated use. The object of the present invention is to provide an electrophotographic photoreceptor that exhibits stable potential characteristics and image characteristics regardless of the usage environment (temperature, humidity), and to provide an electrophotographic apparatus and facsimile equipped with the electrophotographic photoreceptor. .

[0006]

[Means for Solving the Problem] The present invention provides that the Bragg angle 2θ±0.2° in X-ray diffraction of CuKα is 9.0° and 14.2°.
It is characterized by containing crystalline oxytitanium phthalocyanine having strong peaks at 23.9°, 23.9° and 27.1°, and at least one carbonyl compound represented by the following general formula (1). It consists of an electrophotographic photoreceptor. General formula (1) Chemical formula 2 In the formula, Ar1, Ar2, Ar3 and Ar4 represent an aryl group which may have a substituent, and R1 and R2 represent a hydrogen atom or an alkyl group. Specifically, examples of the aryl group include phenyl, naphthyl, and pyridyl, and examples of the alkyl group include methyl, ethyl, and propyl. Examples of the substituent include alkyl groups such as methyl, ethyl and propyl, alkoxy groups such as methoxy and ethoxy, halogen atoms such as fluorine, chlorine and bromine atoms, aryl groups such as phenyl, and hydroxyl groups.

The X-ray diffraction patterns of oxytitanium phthalocyanine in the present invention are shown in FIGS. 1, 2 and 3.
As shown in the figure, the Bragg angle (2θ±0.2°) is 9.0
Strong peaks are shown at positions of 14.2°, 23.9° and 27.1°. The above peaks are the top four points with the highest peak intensities, and are the main peaks. What is characteristic about the X-ray diffraction diagrams in Figures 1, 2, and 3 is that among the four peaks mentioned above, the peak at 27.1° is the strongest, and the peak at 9.0° The peak is the second strongest. Further, there is a peak weaker than the above four points at a position of 17.9°, and an even weaker peak at a position of 13.3°. Also 10.5°
~13.0°, 14.8° ~17.4° and 18.2
There is virtually no peak in the range of 23.2° to 23.2°.

[0008] In the present invention, the shape of the X-ray diffraction peaks differs slightly due to differences in manufacturing conditions and measurement conditions. For example, the tip of each peak may be split. could be. In the case of Figure 1, the peak at 8.9° is near 9.4°, and
The peak at 14.2° has another split peak near 14.1°.

The structure of oxytitanium phthalocyanine is represented by the following formula. Chemical formula 3 In the formula, X1, X2, X3 and X4 represent Cl or Br, and n, m, j and k are integers of 0 to 4.

The present invention also comprises an electrophotographic apparatus equipped with the electrophotographic photoreceptor of the present invention.

The present invention also comprises an electrophotographic apparatus equipped with the electrophotographic photoreceptor of the present invention, and a facsimile machine having a receiving means for receiving image information from a remote terminal.

Typical specific examples of the carbonyl compound represented by the general formula (1) of the present invention are listed below in Tables 1 to 6. However, it is not limited to these compounds.

Table 1 Table 2 Table 3 Table 4 Table 5 Table 6

[0014] The combination of a specific crystalline oxytitanium phthalocyanine and a specific carbonyl compound in the present invention is probably due to the compatibility of the ionization potential or the good steric overlap at the interface between the charge generating substance and the charge transporting substance. Since charge is well injected from the charge-generating substance to the charge-transporting substance, the sensitivity is good, the residual potential is small, and the potential stability during repeated use is considered to be excellent. To exemplify the method for producing crystalline oxytitanium phthalocyanine used in the present invention, for example, titanium tetrachloride and orthophthalodinitrile are reacted in α-chloronaphthalene to obtain dichlorotitanium phthalocyanine. α-chloronaphthalene, trichlorobenzene, dichlorobenzene,
After washing with a solvent such as N-methylpyrrolidone or N,N-dimethylformamide, and then washing with a solvent such as methanol or ethanol, the product is hydrolyzed with hot water to obtain oxytitanium phthalocyanine crystals.

The crystals thus obtained are often a mixture of various polymorphs, and even if this mixture is processed, it is usually difficult to obtain the crystalline form of oxytitanium phthalocyanine used in the present invention. Therefore, in order to make it suitable for use in the present invention, it is first converted into amorphous oxytitanium phthalocyanine by treatment using an acid pacifying method. The obtained amorphous oxytitanium phthalocyanine is treated with methanol at room temperature, under heating or boiling, preferably for at least 1 hour, and then dried under reduced pressure, and further treated with n-propyl ether, n-butyl ether, iso-butyl ether, sec-butyl ether, n-amyl ether, n-butyl methyl ether, n-butyl ethyl ether
For at least 5 hours, preferably 10 hours, using an ether solvent such as ester, ethylene glycol-n-butyl ether, a monoterpene hydrocarbon solvent such as terpinolene or pinene, or a solvent such as liquid paraffin as a dispersion medium. The crystalline oxytitanium phthalocyanine used in the present invention can be obtained by milling for more than 1 hour. Here, the methanol treatment refers to, for example, a suspension stirring treatment of oxytitanium phthalocyanine in methanol. The milling process is a process performed using a milling device such as a sand mill or a ball mill together with a dispersion medium such as glass beads, steel beads, or alumina balls.

[0016] To explain the electrophotographic photoreceptor using crystalline oxytitanium phthalocyanine and a specific carbonyl compound of the present invention, first, the typical layer structure of the electrophotographic photoreceptor is that the single layer photosensitive layer is The layer contains a charge generating material and a charge transporting material in the same layer, and the photosensitive layer is formed on a conductive support. A laminated photosensitive layer has a structure in which a charge generation layer containing a charge generation substance and a charge transport layer containing a charge transport substance are sequentially laminated on a conductive support. The stacking relationship of the layers may be reversed.

The conductive support may be any material as long as it has conductivity, and metals and alloys such as aluminum and stainless steel, metals with conductive layers, alloys, plastics, paper, etc. are used, and the shape is cylindrical or There are film forms.

A subbing layer having barrier and adhesive functions may also be formed between the conductive support and the photosensitive layer. Materials for the undercoat layer include polyvinyl alcohol, polyethylene oxide, ethyl cellulose, and methyl cellulose.
Examples of materials used include casein, polyamide, glue, and gelatin. The material is dissolved in a suitable solvent and applied onto a conductive support. The film thickness is 0.2 to 3.0 μm.

The photosensitive layer consisting of a single layer is prepared by mixing the charge generating substance of the oxytitanium phthalocyanine crystal used in the present invention and the charge transporting substance which is a specific carbonyl compound in a suitable binder resin solution, and then coating and drying the mixture. It is formed. In the photosensitive layer having a laminated structure, the charge generation layer is formed by dispersing the charge generation substance of oxytitanium phthalocyanine crystal used in the present invention together with a suitable binder resin solution, and coating and drying. In this case, the binder resin is You don't have to. Examples of the binder resin include polyester, acrylic resin, polyvinyl carbazole, phenoxy resin, polycarbonate, polyvinyl butyral, polystyrene, polyvinyl acetate, polysulfone, polyarylate, vinylidene chloride/acrylonitrile. Copolymers and the like are mainly used. The charge transport layer is formed by applying and drying a paint in which a carbonyl compound charge transport material used in the present invention and a binder resin are dissolved in a solvent. As the binder resin, the same binder resins as those described above can be used. Coating methods for the photosensitive layer include dip coating, spray coating, spinner coating, and bead coating.
Examples of methods include coating method, blade coating method, and beam coating method. When the photosensitive layer is a single layer, the film thickness is 5 to 40 μm, preferably 10 to 30 μm. Further, when the photosensitive layer has a laminated structure, the thickness of the charge generation layer is 0.01 to 10 μm, preferably 0.05 to 5 μm, and the thickness of the charge transport layer is 5 to 40 μm, preferably 1 μm.
It is 0 to 30 μm. Furthermore, a thin protective layer may be provided on the surface of the photosensitive layer in order to protect the photosensitive layer from external impact.

When the oxytitanium phthalocyanine crystal of the present invention is used as a charge generating substance, it can be mixed with other charge generating substances depending on the purpose.

The electrophotographic photoreceptor of the present invention can be used not only in printers such as laser beam printers, LED printers, and CRT printers, but also in ordinary electrophotographic copying machines, facsimile machines, and other electrophotographic application fields. Can be widely applied.

Next, an electrophotographic apparatus and a facsimile equipped with the electrophotographic photoreceptor of the present invention will be explained.

Next, an electrophotographic apparatus and a facsimile equipped with the electrophotographic photoreceptor of the present invention will be explained. 1st
FIG. 0 shows a schematic configuration of a general transfer type electrophotographic apparatus using the drum-type photoreceptor of the present invention. In the figure, reference numeral 1 denotes a drum-type photoreceptor as an image carrier, which is rotated at a predetermined circumferential speed in the direction of the arrow around an axis 1a. During the rotation process, the photoreceptor 1 is uniformly charged to a predetermined positive or negative potential on its circumferential surface by the charging means 2, and then subjected to light image exposure L (slit exposure/ Ray
laser beam scanning exposure, etc.). As a result, electrostatic latent images corresponding to the exposed images are sequentially formed on the circumferential surface of the photoreceptor. The electrostatic latent image is then developed with toner by a developing means 4, and the toner-developed image is transferred by a transfer means 5 from a paper feed section (not shown) between the photoreceptor 1 and the transfer means 5, when the photoreceptor 1 is rotated. The images are sequentially transferred onto the surface of the transfer material P that is fed in synchronization with the image data. The transfer material P that has undergone the image transfer is separated from the photoreceptor surface and introduced into the image fixing means 8, where the image is fixed and printed out outside the machine as a copy. After the image has been transferred, the surface of the photoreceptor 1 is cleaned by a cleaning means 6 to remove residual toner after transfer, and is subjected to a charge removal process by a pre-exposure means 7 and used repeatedly for image formation. As the uniform charging means 2 for the photoreceptor 1, a corona charging device is generally widely used. Further, as for the transfer device 5, a corona transfer means is generally widely used. An electrophotographic apparatus is constructed by combining a plurality of components such as the above-mentioned photoreceptor, developing means, and cleaning means into an apparatus unit, and this unit is detachably attached to the main body of the apparatus. It may be configured. For example, the photoreceptor 1 and the cleaning means 6 may be integrated into one apparatus unit, and may be configured to be detachable using a guide means such as a rail on the main body of the apparatus. At this time, the above-mentioned device unit may include a charging means and/or a developing means. In addition, when the electrophotographic apparatus is used as a copying machine or a printer, the light image exposure L is the reflected light or transmitted light from the original, or the original is read and converted into a signal, and this signal is used to generate a laser beam. scanning, driving light emitting diode array,
Alternatively, this may be performed by driving a liquid crystal shutter array.

Furthermore, when used as a facsimile printer, the optical image exposure L is exposure for printing received data. FIG. 11 is a block diagram showing an example of this case. A controller 10 controls an image reading section 9 and a printer 18. controller 1
0 is entirely controlled by the CPU 16. The read data from the image reading section is transmitted to the partner station through the transmitting circuit 12. The data received from the other station is sent to the receiving circuit 11.
is sent to the printer 18 through the printer. Predetermined image data is stored in the image memory. Printer controller 1
7 controls a printer 18. 13 is a telephone. After the image received from the line 14 (image information from a remote terminal connected via the line) is demodulated by the receiving circuit 11, the CPU 16 performs signal processing on the image information and sequentially stores it in the image memory 15. be done. and at least 1
When the image of the page is stored in the memory 16, the image of the page is stored. The CPU 16 reads one page of image information from the memory 15 and sends out the one page of image information signaled to the printer controller 17. When the printer controller 17 receives one page of image information from the CPU 16, it controls the printer 18 to record the image information of that page. Note that the CPU 16 receives the next page while the printer 18 is recording. As described above, images are received and recorded.

Next, an example of the production of oxytitanium phthalocyanine crystals used in the present invention will be shown.

Production Example 1 In 100 g of α-chloronaphthalene, 5.0 g of o-phthalodinitrile and 2.0 g of titanium tetrachloride were heated and stirred at 200°C for 3 hours, and then cooled to 50°C to collect the precipitated crystals. After separation by filtration, a paste of dichlorotitanium phthalocyanine was obtained. Next, this was washed with 100 ml of N,N-dimethylformamide heated to 100°C under stirring, then washed twice with 100 ml of methanol at 60°C, and filtered. Further, the obtained paste was stirred in 100 ml of deionized water at 80°C for 1 hour.
After separation by filtration, blue oxytitanium phthalocyanine crystals were obtained. Yield 4.3g

Elemental analysis value (C32H16N8TiO)C
Calculated value 66.68%, actual value 66.50%H Calculated value 2.80%, actual value 2.99%N Calculated value 19.
44% actual value 19.42% Cl calculated value 0.00%, actual value 0.47%

Next, the crystals were dissolved in 30 ml of concentrated sulfuric acid, and dropped into 300 ml of deionized water at 20° C. under stirring to cause reprecipitation, filtration, and thorough washing with water to obtain amorphous oxytitanium. Phthalocyanine was obtained. 4.0 g of amorphous oxytitanium phthalocyanine thus obtained was suspended and stirred in 100 ml of methanol at room temperature (22°C) for 8 hours, filtered, and dried under reduced pressure to obtain low-crystalline oxytitanium phthalocyanine. I got it. 2.0g of this oxytitanium phthalocyanine
Add 40ml of n-butyl ether to 1mm
The milling process with φ glass beads was carried out at room temperature (22℃
) for the next 20 hours. The solid content was taken out from this dispersion, thoroughly washed with methanol and then with water, and dried to obtain crystalline oxytitanium phthalocyanine used in the present invention. Yield 1.8g

The X-ray diffraction pattern of the crystalline oxytitanium phthalocyanine obtained is shown in FIG. In addition, KBr pellets were prepared and the infrared absorption spectrum of this crystal was measured, and the results are shown in FIG. In addition, this crystal was converted into n-butyl ether.
FIG. 8 shows the results of the ultraviolet absorption spectrum measured for the dispersion liquid dispersed in the solution.

Production Example 2 50 ml of pinene was added to 2.0 g of methanol-treated oxytitanium phthalocyanine obtained in the same manner as in Production Example 1, and milled with 1 mm diameter glass beads at room temperature (22°C). I went for 20 hours. The solid content was taken out from this dispersion, thoroughly washed with methanol and then with water, and dried to obtain crystalline oxytitanium phthalocyanine used in the present invention. Yield 1.8g

0031
FIG. 2 shows an X-ray diffraction pattern of the crystalline oxytitanium phthalocyanine obtained.

Production Example 3 100 ml of methanol was added to 4.0 g of amorphous oxytitanium phthalocyanine obtained in the same manner as in Production Example 1, and the mixture was boiled for 30 hours under suspension stirring.
It was filtered and dried under reduced pressure to obtain oxytitanium phthalocyanine crystals. Yield: 3.6g Next, 2.0g of this oxytitanium phthalocyanine was mixed with ethylene glycol-n.
60 ml of -butyl ether was added, and milling was carried out at room temperature (22°C) for 15 hours with glass beads of 1 mm diameter. The solid content was taken out from this dispersion, thoroughly washed with methanol and then with water, and dried to obtain crystalline oxytitanium phthalocyanine used in the present invention. Yield 1.8g

The X-ray diffraction pattern of the crystalline oxytitanium phthalocyanine obtained is shown in FIG.

Comparative Production Example 1 Japanese Patent Application Laid-Open No. 61-239248 (USP 4,728,
592), the so-called α
A crystalline form of oxytitanium phthalocyanine called type was obtained. This X-ray diffraction diagram is shown in FIG.

Comparative Production Example 2 Japanese Patent Application Laid-Open No. 62-67094 (USP 4,66499)
According to the production example disclosed in No. 72), a crystalline oxytitanium phthalocyanine, so-called type A, was obtained. This X-ray diffraction diagram is shown in FIG.

Comparative Production Example 3 According to the production example disclosed in JP-A-64-17066, oxytitanium phthalocyanine having the same crystal form as that disclosed in JP-A-64-17066 was obtained. This X-ray diffraction diagram is shown in FIG. Note that the X-ray diffraction measurements were performed using CuKα rays under the following conditions. Measuring device used: X-ray diffraction device RAD-A manufactured by Rigaku Denki Co., Ltd.
System X-ray tube: Cu, tube voltage: 50KV, tube current: 40mA
, Scan method: 2θ/θ scan, Scan speed: 2
deg. /min. , sampling interval: 0.020d
eg. , start angle (2θ): 3deg. , stop angle (2θ): 40deg. , diversity slit: 0.5deg. , Scattering slit: 0.5d
eg. , Receiving slit: 0.3mm, curved monochromator used

[0037]

EXAMPLES Example 1 A 0.3 μm undercoat layer made of vinyl chloride-maleic anhydride-vinyl acetate copolymer was formed on an aluminum plate. Next, 3 parts (by weight, the same applies hereinafter) of crystalline oxytitanium phthalocyanine obtained in Production Example 1 and 2 parts of polyvinyl butyral were added to 100 parts of cyclohexanone and dispersed in a sand mill for 2.5 hours. This was diluted by adding 100 parts of methyl ethyl ketone, and this dispersion was used to form a charge generation layer having a thickness of 0.3 μm after drying on the undercoat layer. Next, 5 parts of the carbonyl compound of Compound Example 1 and bisphenol Z type polycarbonate (viscosity average molecular weight 34,000)
6.5 parts of chlorobenzene was dissolved in 6 parts of chlorobenzene, and this was coated on the charge generation layer with a Meyer bar to a dry film thickness of 20 μm to form a charge transport layer. This is called photoreceptor 1.

Comparative Example 1 An electrophotographic photoreceptor was prepared in the same manner as in Example 1, except that the α-type oxytitanium phthalocyanine obtained in Comparative Production Example 1 was used, and this was designated as Comparative Photoreceptor 1.

Comparative Example 2 An electrophotographic photoreceptor was prepared in the same manner as in Example 1, except that the A-type oxytitanium phthalocyanine obtained in Comparative Production Example 2 was used, and this was designated as Comparative Photoreceptor 2.

Comparative Example 3 An electrophotographic photoreceptor was prepared in the same manner as in Example 1, except that the same crystal form of oxytitanium phthalocyanine as disclosed in JP-A-64-17066 obtained in Comparative Production Example 3 was used. , this is referred to as comparative photoreceptor 3.

Each of the electrophotographic photoreceptors, Photoreceptor 1, Comparative Photoreceptors 1, 2, and 3, was printed using a laser beam printer (trade name: L).
BP-SX, cylinder of a modified machine manufactured by Canon Inc.
The sensitivity was determined by pasting the plate on the plate, setting the charge so that the dark potential was -700V, irradiating it with laser light with a wavelength of 802 nm, and measuring the amount of light required to lower the -700V potential to -100V. And so. Further, the potential when irradiated with a light amount of 20 μJ/cm 2 was measured as the residual potential Vr. Example 1 Sensitivity: 0.40 μJ/cm2, Vr: -20V Comparative Example 1 Sensitivity: 0.90 μJ/cm2, Vr: -41V Comparative Example 2 Sensitivity: 0.86 μJ/cm2, Vr: -45V Comparative Example 3 Sensitivity: 0.72 μJ/cm2, Vr: -40V

0
[042] Further, an electrophotographic photoreceptor was prepared in the same manner as in Example 1 except for using the crystalline oxytitanium phthalocyanine obtained in Production Example 2 and Production Example 3 as a charge generating substance, and this was used as a photoreceptor. 2 and photoreceptor 3,
When sensitivity was measured in the same manner as in Example 1, high sensitivity characteristics similar to those of Photoreceptor 1 were obtained.

Next, photoconductor 1, comparison photoconductors 1, 2, and 3 were tested in the following environments: humidity 10%, temperature 5°C, humidity 50%, temperature 18°C, humidity 80%, and temperature 35°C. The photoreceptor has a dark potential of -700V and a light potential of -10V.
A durability test was carried out for 3,000 continuous sheets of paper under a setting of 0 V, and the dark area potential and light area potential were measured and the image was evaluated after the durability test. Photoconductor 1 produced images as good as the initial image in any environment and after durability, but comparative photoconductor 1
, 2 and 3 caused background fogging on the white background in any environment, especially when the humidity was 80% and the temperature was 35° C., and this was noticeable in Comparative Photoreceptor 3. Furthermore, when comparative photoreceptors 1, 2, and 3 were adjusted using the density adjustment lever to remove background fog, the density of the black background portion was insufficient.

FIG. 9 shows the distribution of spectral sensitivity of photoreceptor 1 when the maximum value of spectral sensitivity is 100. As described above, the electrophotographic photoreceptor of the present invention exhibits stable sensitivity characteristics in the long wavelength region around 770 to 810 nm.

Examples 2 to 10 Electrophotographic photoreceptors were prepared in the same manner as in Example 1 except that the oxytitanium phthalocyanine crystal obtained in Production Example 1 and several of the compound examples were combined, and photoreceptors 2 to 10 and do. Each photoreceptor was printed using a laser beam printer (as in Example 1).
It was attached to the cylinder of a modified machine (product name: LBP-SX, manufactured by Canon Inc.), charged so that the dark area potential was -700V, and irradiated with laser light with a wavelength of 802 nm. The amount of light EΔ600 required to lower the potential of -700V to -100V was measured. Further 20μJ/c
The potential Vr was measured when a light amount of m2 was irradiated. In addition, each photoreceptor was set to a dark area potential of -700V and a bright area potential of -20V.
A durability test of 5,000 continuous sheets was conducted with the setting reset to 0 V, and the fluctuations ΔVD and ΔVL in the dark potential and bright potential were measured at the initial stage and after the 5,000-sheet durability test. Example 2 [Photoreceptor 2, Compound Example 2] E△600: 0.45 μJ/cm2, ΔVD: -1
5V, ΔVL: +10V, Vr: -30V Example 3 [Photoreceptor 3, Compound Example 3] E△600: 0.46 μJ/cm2, ΔVD: -1
5V, ΔVL: +12V, Vr: -33V Example 4 [Photoreceptor 4, Compound Example 5] E△600: 0.49 μJ/cm2, ΔVD: -1
7V, ΔVL: 12V, Vr: -31V Example 5 [Photoreceptor 5, Compound Example 9] E△600: 0.51 μJ/cm2, ΔVD: -1
8V, ΔVL: +8V, Vr: -35V Example 6 [Photoreceptor 6, Compound Example 10] E△600: 0.48 μJ/cm2, ΔVD: -2
1V, ΔVL: +10V, Vr: -35V Example 7 [Photoreceptor 7, Compound Example 16] E△600: 0.45 μJ/cm2, ΔVD: -2
0V, ΔVL: +15V, Vr: -40V Example 8 [Photoreceptor 8, Compound Example 21] E△600: 0.50 μJ/cm2, ΔVD: -1
5V, ΔVL: +10V, Vr: -45V Example 9 [Photoreceptor 9, Compound Example 29] E△600: 0.52 μJ/cm2, ΔVD: -1
6V, ΔVL: +12V, Vr: -37V Example 10 [Photoreceptor 10, Compound Example 31] E△600:
0.48 μJ/cm2, ΔVD: -18V, ΔVL
:+18V, Vr:-36V

Comparative Examples 4 to 21 Electron production was carried out in the same manner as in Examples 2 to 10, except that the oxytitanium phthalocyanine produced in Comparative Production Examples 1 to 3 and the styryl compound used in Examples 2 to 10 were used in combination. A photographic photoreceptor was prepared and evaluated in the same manner. Comparative Example 4 [Comparative Photoreceptor 4, Comparative Production Example 1, Compound Example 2]
E△600: 0.85 μJ/cm2, ΔVD: -3
8V, ΔVL: +40V, Vr: -76V Comparative Example 5 [Comparative Photoreceptor 5, Comparative Production Example 2, Compound Example 2]
E△600: 0.83 μJ/cm2, ΔVD: -4
0V, ΔVL: +35V, Vr: -75V Comparative Example 6 [Comparative Photoreceptor 6, Comparative Production Example 3, Compound Example 2]
E△600: 0.64 μJ/cm2, ΔVD: -4
2V, ΔVL: +36V, Vr: -70V Comparative Example 7 [Comparative Photoreceptor 7, Comparative Production Example 1, Compound Example 5]
E△600: 0.96 μJ/cm2, ΔVD: -3
8V, ΔVL: +41V, Vr: -80V Comparative Example 8 [Comparative Photoreceptor 8, Comparative Production Example 2, Compound Example 5]
E△600: 0.91 μJ/cm2, ΔVD: -4
5V, ΔVL: +38V, Vr: -81V Comparative Example 9 [Comparative Photoreceptor 9, Comparative Production Example 3, Compound Example 5]
E△600: 0.70 μJ/cm2, ΔVD: -4
0V, ΔVL: +40V, Vr: -78V Comparative Example 10 [Comparative Photoreceptor 10, Comparative Production Example 1, Compound Example 10] E△600: 0.87 μJ/cm2, ΔVD: -4
2V, ΔVL: +35V, Vr: -80V Comparative Example 11 [Comparative Photoreceptor 11, Comparative Production Example 2, Compound Example 10] E△600: 0.82 μJ/cm2, ΔVD: -3
9V, ΔVL: +32V, Vr: -83V Comparative Example 12 [Comparative Photoreceptor 12, Comparative Production Example 3, Compound Example 10] E△600: 0.70 μJ/cm2, ΔVD: -4
1V, ΔVL: +36V, Vr: -78V Comparative Example 13 [Comparative Photoreceptor 13, Comparative Production Example 1, Compound Example 16] E△600: 0.89 μJ/cm2, ΔVD: -5
1V, ΔVL: +45V, Vr: -93V Comparative Example 14 [Comparative Photoreceptor 14, Comparative Production Example 2, Compound Example 16] E△600: 0.87 μJ/cm2, ΔVD: -4
6V, ΔVL: +51V, Vr: -89V Comparative Example 15 [Comparative Photoreceptor 15, Comparative Production Example 3, Compound Example 16] E△600: 0.71 μJ/cm2, ΔVD: -4
7V, ΔVL: +42V, Vr: -82V Comparative Example 16 [Comparative Photoreceptor 16, Comparative Production Example 1, Compound Example 29] E△600: 0.95 μJ/cm2, ΔVD: -4
0V, ΔVL: +43V, Vr: -73V Comparative Example 17 [Comparative Photoreceptor 17, Comparative Production Example 2, Compound Example 29] E△600: 0.89 μJ/cm2, ΔVD: -3
5V, ΔVL: +45V, Vr: -71V Comparative Example 18 [Comparative Photoreceptor 18, Comparative Production Example 3, Compound Example 29] E△600: 0.78 μJ/cm2, ΔVD: -3
6V, ΔVL: +42V, Vr: -81V Comparative Example 19 [Comparative Photoreceptor 19, Comparative Production Example 1, Compound Example 31] E△600: 0.99 μJ/cm2, ΔVD: -4
1V, ΔVL: +50V, Vr: -84V Comparative Example 20 [Comparative Photoreceptor 20, Comparative Production Example 2, Compound Example 31] E△600: 0.96 μJ/cm2, ΔVD: -3
8V, ΔVL: +39V, Vr: -76V Comparative Example 21 [Comparative Photoreceptor 21, Comparative Production Example 3, Compound Example 31] E△600: 0.82 μJ/cm2, ΔVD: -4
5V, ΔVL: +43V, Vr: -78V

Comparative Examples 22 to 27 Compounds H-1, H-2, H-3, H-4, H-5, H- shown in Table 7 were used in place of the carbonyl compound in Example 2.
An electrophotographic photoreceptor was prepared in the same manner as in Example 2, except that No. 6 was used as the charge transport material, and evaluated in the same manner. Table 7 Comparative Example 22 [Comparative Photoreceptor 22, Charge Transport Material H-1] E
△600: 0.66 μJ/cm2, ΔVD: -35
V, ΔVL: +28V, Vr: -71V Comparative Example 23 [Comparative Photoreceptor 23, Charge Transport Material H-2] E
△600: Unable to measure, ΔVD: -, ΔVL: -,
Vr: -201V Comparative Example 24 [Comparative Photoreceptor 24, Charge Transport Material H-3] E
△600: 0.59 μJ/cm2, ΔVD: -25
V, ΔVL: +72V, Vr: -65V Comparative Example 25 [Comparative Photoreceptor 25, Charge Transport Material H-4] E
△600: Unable to measure, ΔVD: -, ΔVL: -,
Vr: -545V Comparative Example 26 [Comparative Photoreceptor 26, Charge Transport Material H-5] E
△600: Unable to measure, ΔVD: -, ΔVL: -,
Vr: -455V Comparative Example 27 [Comparative Photoreceptor 27, Charge Transport Material H-6] E
△600: Unable to measure, ΔVD: -, ΔVL: -,
Vr: -420V From the above results, it can be seen that the electrophotographic photoreceptor of the present invention is extremely excellent in sensitivity, residual potential, and repeatability.

Example 11 An undercoat layer similar to that in Example 1 was formed by bar coating on an aluminum sheet substrate having a thickness of 50 μm, and a charge transport layer similar to that in Example 1 was further formed on this. It was formed to have a thickness of 20 μm. Next, 5 parts of bisphenol Z type polycarbonate was dissolved in 68 parts of cyclohexanone, and Production Example 1 was added to this solution.
After mixing 3 parts of oxytitanium phthalocyanine showing the X-ray diffraction pattern obtained in Example 1 and dispersing it in a sand mill for 1 hour, the mixture was mixed with 5 parts of bisphenol Z type polycarbonate used in Example 1. A dispersion paint was prepared by dissolving 10 parts of a charge transport substance and diluting the mixture by adding 40 parts of tetrahydrofuran and 40 parts of dichloromethane. Spray this paint
Apply on the charge transport layer using coating method and dry to 6μm.
A thick charge generation layer is formed to produce an electrophotographic photoreceptor, which is referred to as photoreceptor 11.

Comparative Example 28 An electrophotographic photoreceptor was prepared in the same manner as in Example 11 except that the α-type oxytitanium phthalocyanine produced in Comparative Production Example 1 was used as a charge generating substance, and this was used as Comparative Photoreceptor 2.
8.

Comparative Example 29 An electrophotographic photoreceptor was prepared in the same manner as in Example 11, except that the A-type oxytitanium phthalocyanine produced in Comparative Production Example 2 was used as the charge-generating substance, and this was used as Comparative Photoreceptor 2.
9.

Comparative Example 30 JP-A-64 produced in Comparative Production Example 3 as a charge generating substance
An electrophotographic photoreceptor was prepared in the same manner as in Example 11, except that oxytitanium phthalocyanine having the same crystal form as disclosed in Japanese Patent No. 17066 was used, and this was designated as Comparative Photoreceptor 30.

Photoreceptors 11, comparative photoreceptors 28, 29 and 30 were evaluated using an electrostatic tester (EPA-8100, manufactured by Kawaguchi Electric Co., Ltd.). In the evaluation, the surface potential was first set to +700V due to positive corona charging, and then 802 nm was separated using a monochromator.
The amount of light was measured when the surface potential decreased to +200V by exposing the sample to monochromatic light. Show the results. Photoconductor 11 Sensitivity: 0.54μJ/cm2 Comparison photoconductor 28 Sensitivity: 1.05μJ/cm2 Comparison photoconductor 29
Sensitivity: 1.02 μJ/cm2 Comparative photoreceptor 30 Sensitivity: 0.92 μJ/cm2

[0053]

Effects of the Invention The electrophotographic photoreceptor of the present invention has a photosensitive layer containing a specific crystal form of oxytitanium phthalocyanine as a charge-generating substance and a specific carbonyl compound as a charge-transporting substance. It has the remarkable effects of having high sensitivity at the diode oscillation wavelength, (2) exhibiting stable image characteristics in the electrophotographic process, and (3) excellent potential stability. Furthermore, similar effects can be achieved in electrophotographic devices and facsimile machines equipped with the electrophotographic photoreceptor.

[Brief explanation of the drawing]

FIG. 1 is an X-ray diffraction diagram of crystalline oxytitanium phthalocyanine obtained in Production Example 1.

FIG. 2 is an X-ray diffraction diagram of crystalline oxytitanium phthalocyanine obtained in Production Example 2.

FIG. 3 is an X-ray diffraction diagram of crystalline oxytitanium phthalocyanine obtained in Production Example 3.

FIG. 4 is an X-ray diffraction diagram of oxytitanium phthalocyanine obtained in Comparative Production Example 1.

FIG. 5 is an X-ray diffraction diagram of oxytitanium phthalocyanine obtained in Comparative Production Example 2.

FIG. 6 is an X-ray diffraction diagram of oxytitanium phthalocyanine obtained in Comparative Production Example 3.

FIG. 7 is an infrared absorption spectrum diagram (KBr method) of crystalline oxytitanium phthalocyanine obtained in Production Example 1.

FIG. 8 is an ultraviolet absorption spectrum diagram of crystalline oxytitanium phthalocyanine obtained in Production Example 1.

FIG. 9: Electrophotographic photoreceptor produced in Example 1 (Photoreceptor 1
) is a spectral sensitivity distribution diagram.

FIG. 10 is a schematic configuration diagram of a general transfer type electrophotographic apparatus equipped with the electrophotographic photoreceptor of the present invention.

FIG. 11 is a block diagram of a facsimile machine using an electrophotographic apparatus equipped with the electrophotographic photoreceptor of the present invention as a printer.

[Explanation of symbols]

1 Drum-type photoreceptor as an image carrier (electrophotographic photoreceptor of the present invention) 1a Shaft 2 Corona charging device 3 Exposure section 4 Developing means 5 Transfer means 6 Cleaning means 7 Pre-exposure means 8 Image fixing means L Optical image Exposure P Transfer material 9 that has undergone image transfer Image reading unit 10 Controller 11 Receiving circuit 12 Transmitting circuit 13 Telephone 14 Line 15 Image memory 16 CPU 17 Printer controller 18 Printer

Claims (3)

[Claims] [Claim 1] Bragg angles 2θ±0.2° in X-ray diffraction of CuKα are 9.0°, 14.2°, and 23.9°.
and an electrophotographic photoreceptor comprising crystalline oxytitanium phthalocyanine having a strong peak at 27.1°, and at least one carbonyl compound represented by the following general formula (1). . General formula (1) Chemical formula 1 In the formula, Ar1, Ar2, Ar3 and Ar4 represent an aryl group which may have a substituent, and R1 and R2 represent a hydrogen atom or an alkyl group. 2. An electrophotographic apparatus comprising the electrophotographic photoreceptor according to claim 1. 3. A facsimile machine comprising an electrophotographic apparatus comprising the electrophotographic photoreceptor according to claim 1 and a receiving means for receiving image information from a remote terminal.