JPS62273553A - 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 a p-type semiconductor contg. an amorphous silicon contg. hydrogen atom as a main component, and also contg. boron atom as an impurity, 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 as the intermediate layer. The p-type semiconductor comprising the amorphous silicon contg. hydrogen atom as the main component, and also contg. boron atom and at least one kind of carbon atom, nitrogen atom or oxygen atom as an impurity is used as the photoconductive layer. The further preferable org. zirconium compd. is a zirconium complex and a zirconium alkoxide. 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 amorphous silicon in the photosensitive layer.

In the conventional electrophotographic method, an electrostatic latent image is formed by charging a photoreceptor and exposing it to light, and after developing this latent image with a developer such as a toner,
This is a method in which a toner image is transferred and fixed onto transfer paper, and the copy is grooved. The photoreceptor used in this electrophotographic method basically has a photosensitive layer laminated on a conductive substrate. Conventionally, the materials constituting the photosensitive layer have been inorganic photosensitive materials such as selenium or selenium alloys, cadmium sulfide, and zinc oxide, or organic photosensitive materials such as polyvinylcarbazole, trinitrofluorenone, bisazo pigments, phthalocyanine, pyrazoline, and hydrazone. Photosensitive materials are known,
The photosensitive material is used in a single layer or in a single layer.

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 SiH4 gas. Hydrogen atoms are incorporated into the material 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, an amorphous silicon photoreceptor is charged, imagewise exposed to form an electrostatic latent image,
During subsequent development, the surface charge on the photoreceptor will attenuate until the image exposure process or even the charge on the areas that have not been exposed to light during the development process, making it impossible to obtain the charging potential necessary for development. . 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 laminated an intermediate layer on a conductive substrate, coated it with a photoconductive layer made of amorphous silicon, and It has been found that the above object can be achieved by using a dried and cured solution of an intermediate layer containing at least one type of organic zirconium compound. The photoconductive layer is a p-type semiconductor mainly composed of amorphous silicon containing hydrogen atoms, containing boron atoms as impurities, and further containing at least one of carbon atoms, nitrogen atoms, or oxygen atoms. use

Thus, according to the present invention, in an electrophotographic photoreceptor formed by sequentially forming an intermediate layer and a photoconductive layer on a conductive substrate, the photoconductive layer is mainly made of amorphous silicon containing hydrogen atoms. A dry cured product of a solution comprising a p-type semiconductor containing a boron atom as an impurity and further containing at least one type of carbon atom, nitrogen atom, or oxygen atom, the intermediate 1 containing at least one type of organic zirconium compound. A photoreceptor for electrophotography is provided, characterized in that the photoreceptor comprises:

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 zirconium alkoxides. Preferred examples of these include zirconium tetrakisacetylacetonate, zirconium dibutoxybisacetylacetonate, zirconium tryptoquine acetylacetonate, zirconium trifluoroacetylacetonate, zirconium tetra-n-propoxide, zirconium tetra-iso-propoxide. Examples include zirconium-n-butoxide, zirconium isobutoxide, and the like.

To obtain the electrophotographic photoreceptor of the present invention, a solution of one or more of the above organic zirconium compounds dissolved in a suitable solvent is applied. Further, at this time, a solution obtained by mixing these organic zirconium compounds with an organic silicon compound may be used. Compounds generally called silane coupling agents are suitable as the organosilicon compound, and examples thereof include vinyltrichlorane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, and T-glycidoxypropyltrimethquine. Silane, T-methacryloquinepropyltrimethoxysilane, N-β(aminoethyl)T-aminopropyltrimethoxysilane, N-β(aminoethyl)T-aminopropylmethyldimethoxysilane, γ-chloropropyltrimethoxysilane , γ-mercaptopropyltrimethoxysilane, r-ami/propyltriethoxysilane,
Examples include methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmonomethoxysilane, diphenyldimethoxysilane, diphenyljethoxysilane, and monophenyltrimethoxysilane. When such a silane coupling agent is mixed and used, the silane coupling agent accounts for 5 to 50% of the total solid weight.
It is better to make it so that

Thus, a solution containing an organozirconium compound and optionally an organosilicon compound is applied onto a conductive substrate by methods such as spray coating, dip coating, knife coating or roll coating, dried and cured, and then applied. The electrophotographic photoreceptor of the present invention is produced by laminating a photoconductive layer on the substrate.

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

The photoconductive layer mainly composed of amorphous silicon is SIH S+2.
)1s, 5r3Ha, S+4) 110%, etc., or a mixture thereof, is used as a raw material and formed on the intermediate layer 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) in which silane (SiH, ) gas, etc. is decomposed 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 contain hydrogen with -1 efficiency, 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 5it14, S12) 1g.

The photoconductive layer of the electrophotographic photoreceptor of the present invention is composed of a p-type semiconductor mainly composed of amorphous silicon containing hydrogen atoms and containing boron atoms as impurities, and further containing carbon atoms, nitrogen atoms or Contains at least one type of oxygen atom. The inclusion of such atoms is particularly preferable from the viewpoint of increasing the dark resistance of the photosensitive film, increasing the photosensitivity, and further increasing the charging ability (charging potential per unit film thickness).

Diborane (BiHs) gas is usually used as a raw material for adding boron (B) atoms to this amorphous silicon-Sg optical layer. In this case, the amount of Blicon added is 10 to 1001]
It is about 111m.

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 region. 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 together with other gases. , a gaseous compound containing necessary elements may be introduced to perform glow discharge decomposition. As mentioned above, the effective discharge conditions for forming a photoconductive layer made of amorphous silicon by plasma removal are, for example, in the case of alternating current discharge, the frequency is usually 0.1 to 30! JHz, degree of vacuum during discharge is 0, 1 to 5 Torr, substrate heating temperature is 100 to 4
It is 00℃. Therefore, the film thickness of the photoconductive layer containing amorphous silicon is 1 to 100 μm, particularly 10 to 50 μm.
It is preferable that

As the conductive substrate, metal such as aluminum, nickel, chromium, stainless steel, or brass, plastic 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 a 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 123 cc per minute, hydrogen dilution to
o Oppm diborane (LHg) gas at 30cc per minute
, and 100% ethylene (C2H4) gas at 15 min.
cc, and 75cc of 100% hydrogen (H2) gas per minute.
After maintaining the internal pressure in the reaction chamber at 0.5 Torr, 13.57 MHz high frequency power was applied to generate a glow discharge, and the output of the high frequency power supply was increased to 85 Torr.
I kept it at W. In this way, a photoreceptor having a 25 μm thick photoconductive layer made of a p-type semiconductor mainly composed of amorphous silicon, containing boron atoms as impurities, and further containing hydrogen and carbon was fabricated on a cylindrical Af substrate. Obtained.

When the photoreceptor thus obtained was placed in a copying machine and the image quality was evaluated using a positive corona charging method, it was found that the image density was not sufficient for practical use.

Example 1: On a cylindrical A42 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 heavy NB 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 give a 0.2
A μm thick intermediate layer was provided.

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 possessed the excellent properties of amorphous silicon, such as surface hardness, abrasion resistance, and heat resistance.

Obtained in this way. When the photoreceptor 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. Also, the copy operation is
Although the process was repeated 10,000 times, no decrease in image density was observed.

Comparative Example 2: A cylindrical Aβ group 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% silicon (Si) was placed in the reaction chamber.
H<) gas per minute at 120cc1000p of hydrogen dilution
pm Diborane (82H6) gas was introduced at 3Qcc per minute, 100% nitrogen (N2) gas was introduced at 90cc per minute, and 100% hydrogen (H2) gas was introduced at 1Qcc per minute.
After maintaining the internal pressure in the reaction tank at 0.5 Torr, 13.
A 56 MHz high frequency 211!2 power was applied to generate a glow discharge, and the output of the high frequency power source was maintained at 85W. As shown in step 2, place a cylindrical plate on 2 substrates with a thickness of 25 μm.
A photoreceptor having a photoconductive layer consisting of a p-type semiconductor mainly composed of amorphous silicon and containing boron as impurities and hydrogen and nitrogen is 1 fathom.

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 i of 11 degrees that could withstand practical use was not obtained.

Example 2: On a cylindrical Aβ substrate having the same shape as Comparative Example 2, 1 part by weight of zirconium tetrabutoxide and 10 parts by weight of ethyl alcohol were added.
A 0 part by weight solution was dip coated and dried in an oven at 250°C for 2 hours to provide a 0.2 μm thick intermediate layer. next,
Comparative Example 2 was applied onto this intermediate layer by the same method as Comparative Example 2.
A photoconductor 1 mainly composed of amorphous silicon having the same content as above was provided with approximately the same film thickness as Comparative Example 2.

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, even though the copying operation was repeated 50,000 times, no decrease in image density was observed.

Comparative Example 3: A cylindrical human β 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 (Si) was placed in the reaction chamber.
Hl) gas per minute at 120cc1000pp of hydrogen dilution
m diborane (B2116) gas at 30 cc/min and 100% oxygen (02) gas at 1.0 cc/min. Qcc, and then 100% hydrogen (H2) gas was introduced at a rate of 89cc per minute to maintain the internal pressure of O157orr in the reaction tank, and then 13
．． 56! , lHz high frequency power was applied to generate glow discharge, and the output of the high frequency power supply was maintained at 85W. 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 a p-type semiconductor consisting mainly of amorphous silicon and further containing hydrogen and oxygen as impurities.

When the photoreceptor thus obtained was placed in a copying machine and image quality was evaluated using a positive corona charging method, an image density that could withstand practical use was not obtained.

Example 3: On a cylindrical Aβ substrate having the same shape as Comparative Example 3, 1 part by weight of zirconium tetrabutoxide and 1 part by weight of methyltrimethoxysilane were placed. ! , parts, ethyl alcohol 100ffi1
100 parts by weight of isopropyl alcohol was applied by dip coating, and dried in an oven at 250° C. for 2 hours to give a solution of 0.05 parts by weight.
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 formed by the same method as in Comparative Example 3 and having a thickness substantially the same as that 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.

Effects of the Invention The electrophotographic photoreceptor of the present invention maintains the excellent properties of a photoreceptor made of amorphous silicon, such as high 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 composed of amorphous silicon containing hydrogen atoms as an impurity. The intermediate layer is made of a p-type semiconductor containing a boron atom, and 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.