JPS62273568A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain the titled body having a very small dark attenuation of the electrostatic charge potential by constituting a photoconductive layer from an i-type semiconductor comprising an amorphous silicon contg. hydrogen atom as a main component, and by constituting an intermediate layer from a dried curing material of a solution contg. at least one kind of an org. zirconium compd. CONSTITUTION:The intermediate layer is laminated on a conductive substrate, and the photoconductive layer composed of the amorphous silicon is coated on the intermediate layer. The dried curing material of the solution contg. at least one kind of the org. zirconium compd. is used the intermediate layer. The i-type semiconductor contg. the amorphous silicon contg. hydrogen atom as the main component, and also contg. at least one of carbon atom, nitrogen atom, or oxygen atom is used as the photoconductive layer. The further preferable org. zirconium compd. is a zirconium complex and a zirconium alkoxide. The preferable org. zirconium compd. is exemplified by zirconium tetrakis acetyl acetonate, etc. Thus, the high mechanical strength, the high durability, the high heat-resisting property and the high photosensitivity of the titled body are maintained, and the high electric charge holding power of the titled body is obtd., without being affected by the surroundings of an outside and the number of using, thereby obtaining the picture image having excellent quality.

Description

3. Detailed Description of the Invention Field of Industrial Application The present invention relates to an electrophotographic photoreceptor, and particularly to an electrophotographic photoreceptor using G-crystalline silicon in the photosensitive layer.

In the conventional electrophotographic method, an electrostatic latent image is formed by charging a photoreceptor and exposing it to 1' quadrature, and this latent image is developed with a developer called toner.
After printing, the toner image is transferred to transfer paper and fixed to obtain a copy. The photoreceptor used in this electrophotographic method basically has a photosensitive layer laminated on a conductive substrate. Conventionally, materials constituting the photosensitive layer include stepless photosensitive materials such as selenium, selenium alloys, cadmium sulfide, and zinc oxide, or polyvinylcarbazole,
Organic photosensitive materials such as trinitrofluorenone, bisazo pigments, phthalonanine, pyrazoline, and hydrazone are known, and Photosensitive 1 is used as a single layer or in adjacent layers.

Problems to be Solved by the Invention However, these conventionally used photosensitive layers have problems in durability, heat resistance, photosensitivity, etc. that still need to be solved.

In recent years, photoreceptors using amorphous silicon as the photosensitive layer have been known, and various attempts have been made to improve them. This photoreceptor using amorphous silicon is one in which an amorphous film of silicon is formed on a conductive substrate by a glow discharge decomposition method using Si20 gas. Hydrogen atoms are incorporated to exhibit photoconductivity. This amorphous silicon photoreceptor has a photosensitive layer that has a high surface hardness, is resistant to scratches, is resistant to abrasion, has high heat resistance, and is excellent in mechanical strength. Furthermore, amorphous silicon has a wide spectral sensitivity range and has excellent photosensitivity, such as high photosensitivity. However, on the other hand, photoreceptors using amorphous silicon have the disadvantage that dark decay is large and a sufficient charging potential cannot be obtained even when charged. That is, when an amorphous silicon photoreceptor is charged, imagewise exposed to form an electrostatic latent image, and then developed, the surface charge on the photoreceptor increases before the image exposure step or the development step. Even the charge on the portions not irradiated with light is attenuated, and the charging potential required for development cannot be increased by one. This attenuation of the charging potential is likely to change depending on the influence of environmental conditions, and in particular, the charging potential decreases significantly in a high temperature and high humidity environment. Furthermore, when an amorphous silicon photoreceptor is used repeatedly, its charging potential gradually decreases. If a copy is made using a photoreceptor with such a large dark attenuation of the charged potential, the copy will have low image density and poor reproducibility of halftones.

An object of the present invention is to provide an electrophotographic photoreceptor that eliminates the above-mentioned drawbacks of photoreceptors using amorphous silicon.

Furthermore, the object of the present invention is to use amorphous silicon, and
An object of the present invention is to provide an electrophotographic photoreceptor in which the dark decay of the charged potential is extremely small.

Another object of the present invention is to provide an electrophotographic photoreceptor whose charging characteristics are not affected by changes in the cloud surroundings of the external environment.

Another object of the present invention is to provide an electrophotographic photoreceptor with excellent image quality even after repeated use.

A further object of the present invention is to provide an electrophotographic photoreceptor having excellent electrophotographic properties such as mechanical strength, durability, heat resistance, and photosensitivity.

Means for Solving the Problems As a result of extensive research, the inventor of the present invention formed an intermediate layer on a conductive substrate, coated it with a photoconductive layer made of amorphous silicon, It has been found that the above object can be achieved by using, as the intermediate layer, a dried IF product of a solution containing at least one type of organic zirconium compound. As the photoconductive layer, a type 1 semiconductor is used which is mainly composed of amorphous silicon containing hydrogen atoms and further contains at least one of carbon atoms, nitrogen atoms, and oxygen atoms.

Thus, according to the present invention, in an electrophotographic photoreceptor comprising an intermediate layer and a photoconductive layer sequentially laminated on a conductive substrate, the photoconductive layer is mainly made of amorphous silicon containing hydrogen atoms. , further characterized in that the intermediate layer is made of an l-type semiconductor containing at least one type of carbon atom, nitrogen atom, or oxygen atom, and the intermediate layer is made of a dried and cured product of a solution containing at least one type of organic zirconium compound. An electrophotographic photoreceptor is provided.

Although various organic zirconium compounds can be used to form the intermediate layer of the electrophotographic photoreceptor of the present invention, particularly preferred are zirconium complexes and zirminilum alkoxide. Preferred examples of these include zirconium tetrakisacetylacetonate, zirconium dibutoxybisacetylacetonate, zirconium tributoxyacetylacetonate, zirconium trifluoroacetylacetonate, zirconium tetra-n-propoxide, zirconium tetra-iso-propoxide. Examples include zirconium-n-butoxide, zirconium isobutoxide, and the like.

In preparing the electrophotographic photoreceptor of the present invention, a solution containing one or more of the above-mentioned organic zirconium compounds dissolved in a suitable solvent is applied. Also, at this time,
A solution obtained by mixing these organic zirconium compounds with an organic silicon compound may also be used. Compounds generally called silane coupling agents are suitable as the organosilicon compound, such as vinyltrichlorane, vinyltriethoxysilane, vinyltris(β-methquinethoquine)silane, and T-glycidoxypropyltrimethoxysilane. , γ-methacryloxypropyltrimethoxysilane, N-β(aminoethyl)T-amino/propyltrimethoxysilane, N-β(aminoethyl)T-aminopropylmethyldimethoxysilane, γ-chloropropyltrimethoxysilane, Examples include γ-mercaptopropyltrimethoxysilane, T-aminopropyltriethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmonomethoxysilane, diphenyljethoxysilane, diphenyljethoxysilane, and monophenyltrimethoxysilane. When such silane coupling agents are mixed and used, it is preferable that the silane coupling agents account for 5 to 50% of the total solid weight.

Thus, a solution containing an organozirconium compound and optionally an organosilicon compound is applied onto a conductive substrate by a method such as spray coating, dip coating, knife coating or roll coating, followed by drying and curing. The electrophotographic photoreceptor of the present invention can be obtained by laminating a photoconductive layer thereon.

The drying and curing temperature can be set at any temperature between 100 and 400°C. The thickness of the intermediate layer finally obtained can also be set arbitrarily, but 0.1 to 10 μm is suitable.

° The photoconductive layer mainly composed of amorphous silicon is made of SiH,...
The intermediate layer is formed using one type of hydrogen silicon gas such as 5i2L, 513H1l, SjJ+o, or a mixture thereof as a raw material by a method such as a glow discharge method, a sputtering method, an ion blasting method, or a vacuum evaporation method. Especially the plug? CV D (Chemical V
A method (glow discharge method) of decomposing silane (SiH) gas or the like by glow discharge using an apor deposition method is preferable from the viewpoint of controlling the hydrogen content in the film.

Further, in this case, in order to more efficiently contain hydrogen, hydrogen (H2) gas may be separately introduced into the plasma CVD apparatus at the same time as silane gas or the like. Furthermore, from the viewpoint of film growth rate, it is preferable to use SiH4,5i2L.

The photoconductive layer of the electrophotographic photoreceptor of the present invention is made of an l-type semiconductor mainly composed of amorphous silicon containing hydrogen atoms, and further contains at least one of carbon atoms, nitrogen atoms, and oxygen atoms. Contains one type. The inclusion of such atoms particularly increases the dark resistance of the photosensitive layer, increases the photosensitivity, and further increases the charging ability (charging potential per unit film).
This is preferable in terms of the increase in .

Note that in this amorphous silicon photosensitive layer, the layer is more lubricated.
A trace amount of boron (B) can be added to make it a type semiconductor. The addition of atoms at this time is usually diborane (B
2H6) gas is used as the raw material.

In this case, the amount of B atoms added is 10 to 100ρplTl
This is the extent of

Furthermore, it is also possible to add an element such as germanium (Ge) to the photoconductive layer film for the purpose of increasing the sensitivity of the photoreceptor in the long wavelength range. Further, by adding halogen atoms, it is also possible to increase the dark resistance.

Thus, in order to prepare the photoconductive layer of the electrophotographic photoreceptor of the present invention, silicon hydride gas, which is the main raw material, and hydrogen gas, if desired, are used in a plasma CVD apparatus, and together with these gases, Glow discharge decomposition may be performed by introducing a gaseous compound containing the necessary elements. As mentioned above, effective discharge conditions for forming a photoconductor made of amorphous silicon by the plasma CVD method include, for example, in the case of AC discharge, the frequency is usually 0.1 to 3 QMHz, and the degree of vacuum during discharge. is 0.1~5 Torr, substrate heating temperature is 100~
The temperature is 400°C. Therefore, the film thickness of the photoconductive layer mainly composed of amorphous silicon is 1 to 100 μm, particularly 10 to 50 μm.
It is preferable to set it to m.

As the conductive substrate, a metal such as aluminum, nickel, chromium, stainless steel, or brass, a plastic sheet or glass having a conductive film, or paper treated to be conductive can be used. Moreover, the shape of the conductive substrate can be any shape such as a cylindrical shape, a flat plate shape, an endless belt shape, or the like.

EXAMPLES Next, the electrophotographic photoreceptor of the present invention will be further explained with reference to comparative examples and examples of the present invention.

Comparative Example 1: A cylindrical Aβ substrate was installed at a predetermined position in the reaction chamber of a capacitively coupled plasma CVD apparatus, the substrate temperature was maintained at a predetermined temperature of 250°C, and 100% Silica 7 (SI) was placed in the reaction chamber.
84) 12 Qcc of gas per minute, 10 of hydrogen dilution
Qppm diborane (82H,) gas 20CC1 per minute
100% ethylene (C2H4) gas was introduced at a rate of 12cc per minute, and 100% hydrogen (N2) gas was introduced at a rate of 88cc per minute to maintain an internal pressure of Q, 5 Torr in the reaction tank, and then a high frequency power of 13.56MHz was applied. The output of the high frequency power source was maintained at 85W by turning on the battery to generate a glow discharge. In this way, a thickness of 25 mm was placed on the cylindrical Aj2 substrate.
A photoreceptor was obtained having a photoconductive layer consisting of an l-type semiconductor mainly composed of micrometer-sized amorphous silicon and containing hydrogen and carbon.

When the photoreceptor obtained in this way was placed in a copying machine and the image quality was evaluated using a positive corona charging method, an image density that was acceptable for practical use was initially obtained, but as copying operations were repeated, it gradually deteriorated. The image density decreased.

Example 1: On a cylindrical A1 substrate having the same shape as Comparative Example 1, 1 part by weight of zirconium acetylacetone and 50 parts by weight of methyl alcohol were added.
A solution consisting of 11 parts of FF and 20 parts by weight of n-butyl alcohol was applied by dip coating and dried in an oven at 250° C. for 2 hours to form an intermediate layer with a thickness of 0.2 μm.

Next, on this intermediate layer, a photoconductive layer mainly made of amorphous silicon having the same content as in Comparative Example 1 was provided by the same method as in Comparative Example 1, and with almost the same thickness as in Comparative Example 1.

The photoconductive layer thus obtained had properties similar to ceramics, and had the same surface hardness, abrasion resistance, and heat resistance that are excellent properties of amorphous silicon.

When the photoreceptor thus obtained was placed in a copying machine and the image quality was evaluated using a positive corona charging method, a 1-degree image with no practical problems was obtained at the initial stage. Further, although the copying operation was repeated 50,000 times, no decrease in image density was observed. At the same time, copying tests conducted using the negative corona charging method also gave good results, similar to those using the positive charging method.

Comparative Example 2: A cylindrical Al base was installed at a predetermined position in the reaction chamber of a capacitively coupled plasma CVD apparatus, the substrate temperature was maintained at a predetermined temperature of 250°C, and 100% silane (Si) was placed in the reaction chamber.
H,) gas at 12 Qcc per minute, 1009 parts m of hydrogen dilution Diborane (B,H,) gas at 2'OCC,
100% nitrogen (N2) gas at 85 c/min (plus 1
After introducing 00% hydrogen (N2) gas at a rate of 15 cc per minute and maintaining the internal pressure in the reaction tank at Q, 5 Torr, 13.5
6! A high frequency power of JHz was applied to generate a glow discharge, and the output of the high frequency power source was maintained at 85W. In this way, a film with a thickness of 25 μm was placed on a cylindrical Afl substrate.
A photoreceptor having a photoconductive layer made of an l-type semiconductor mainly composed of amorphous silicon and containing hydrogen and nitrogen was prepared.

When the photoreceptor obtained in this way was placed in a copying machine and the image quality was evaluated using a positive corona charging method, an image density of one image that was acceptable for practical use was initially obtained, but as copying operations were repeated, The image density gradually decreased.

Example 2: 1 part by weight of zirconium tetrabutoxide and 1 part by weight of ethyl alcohol were placed on a β substrate in a cylindrical shape 1 having the opposite shape to that in Comparative Example 2.
Soak in 00 parts by weight solution? It was coated and dried in an oven at 250° C. for 2 hours to form an intermediate layer of 0.2 μm thick. Next, on this intermediate layer, by the same method as in Comparative Example 2, a photoconductive layer mainly composed of amorphous silicon having the same content as in Comparative Example 2 was provided with approximately the same thickness as in Comparative Example 2.

When the photoreceptor thus prepared was placed in a copying machine and the image quality was evaluated using a positive corona charging method, an image density that was acceptable for practical use was obtained at the initial stage. Also, the copy operation is
Although the process was repeated 10,000 times, no decrease in image density was observed. At the same time, copying tests conducted using the negative corona charging method also gave good results, similar to those using the positive charging method.

Comparative Example 3: A cylindrical A42 substrate was installed at a predetermined position in the reaction chamber of a capacitively coupled plasma CVD apparatus, the substrate temperature was maintained at a predetermined temperature of 250°C, and 100% silane (S) was placed in the reaction chamber.
iH,) gas at 12 Qcc per minute, 100 p of hydrogen dilution
pm Diborane (B2H6) gas at 20 CC1/min and 100% oxygen (0□) gas at 1.0 C/min. Qcc, and then 100% hydrogen (H2) gas was introduced at a rate of 99 cc/min to maintain the internal pressure of Q, 5 Torr, and then 13
．． Turn on the output of the 56 M'Az high-rise 'y1 power supply,
A glow discharge was generated and the output of the high frequency power source was maintained at 85W. In this way, a photoreceptor having a 25 μm thick photoconductive layer made of an l-type semiconductor mainly composed of amorphous silicon and containing hydrogen and oxygen on a cylindrical i-substrate was exposed.

When the photoreceptor obtained in this way was placed in a copying machine and the image quality was evaluated using a positive corona charging method, an image density that was acceptable for practical use was initially obtained, but as copying operations were repeated, Image density gradually decreased.

Example 3: On a cylindrical Af substrate having the same shape as Comparative Example 3, 1 part by weight of zirconium tetrabutoxide, 1 part by weight of methyltrimethoxysilane, and 1 ff by weight of ethyl alcohol 10 C1 were added.
l, isopropyl alcohol 100! A solution consisting of several parts was applied by dip coating, and dried in an oven at 250°C for 2 hours to give a coating of 0.
A 1 μm thick intermediate layer was provided.

Next, on this intermediate layer, a photoconductive layer mainly composed of amorphous silicon having the same contents as in Comparative Example 3 was provided by the same method as in Comparative Example 3, with approximately the same thickness as in Comparative Example 3.

When the photoreceptor thus obtained was placed in a copying machine and the image quality was evaluated using a positive corona charging method, an image density that was acceptable for practical use was obtained at the initial stage. Further, although the copying operation was repeated 50,000 times, no decrease in image density was observed. At the same time, a copying test conducted using the negative corona charging method also gave good results compared to the positive charging method.

Effects of the Invention The electrophotographic photoreceptor of the present invention retains the excellent properties of a photoreceptor made of amorphous silicon, such as high mechanical strength, high durability, high heat resistance, and high photosensitivity, and is also resistant to the external environment. Tin has a high charge retention ability and can provide images of excellent quality.

Claims (1)

[Scope of Claims] An electrophotographic photoreceptor comprising an intermediate layer and a photoconductive layer sequentially laminated on a conductive substrate, wherein the photoconductive layer is mainly made of amorphous silicon containing hydrogen atoms. The intermediate layer further contains at least one type of carbon atom, nitrogen atom, or oxygen atom, and the intermediate layer contains at least one organic zirconium compound.
1. A photoreceptor for electrophotography, characterized in that it is made of a dried and cured product of a solution containing various types of photoreceptors.