JPH0488352A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a high photosensitivity over the entire region of visible light and to stably obtain good images by successively laminating an amorphous silicon layer, a specific 2nd amorphous silicon carbide layer and an optical org. semiconductor layer on a specific 1st amorphous silicon carbide a-SiC layer. CONSTITUTION:The 1st a-SiC layer 2 having the atom comps. ratios within a 0.2<x<0.5 range in (x) value of Si1-xCx and the 1st a-SiC layer 2 contg. 1 to 10,000ppm periodic table group IIIa element or 5,000ppm group Va element, the a-SiC layer 3, the 2nd a-SiC layer 4 having the atom compsn. ratios within a 0.2<y<0.5 range in (y) value of Si1-yCy, and the optical org. semiconductor layer 5 are successively laminated on a substrate 1. The high photosensitivity over the entire region of visible light is obtd. in this way and the unequal densities of images are decreased, by which the good images are stably obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophotographic photoreceptor comprising an amorphous silicon carbide layer or a laminated layer of an amorphous silicon layer and an organic optical semiconductor layer.

[Prior art and its problems]

The electrophotographic photoreceptor proposed in JP-A-56-14241 has a structure in which amorphous silicon carbide (hereinafter amorphous silicon carbide is abbreviated as a-3iC) and an organic optical semiconductor layer are laminated on a substrate. −
The 3iC layer is used as a carrier excitation layer.

However, according to the electrophotographic photoreceptor having the above structure, the a-3iC layer has a large optical bandgap, so the sensitivity on the short wavelength side is good, but on the other hand, the sensitivity on the long wavelength side is insufficient. As a result, when a PPC (plain paper copier) is used, the sensitivity is insufficient in the wavelength range of 600 nm or more, which ranges from yellow to red, and as a result, for color originals, etc., the sensitivity in the visible range is poor. The problem is that it cannot be done.

Furthermore, in the electrophotographic photoreceptor proposed in JP-A No. 56-25743, an amorphous silicon photosensitive layer (hereinafter amorphous silicon is abbreviated as a-3i), an a-3iC transition layer, and an organic photosemiconductor layer are formed on a substrate. When the a-3i layer and the aSiC layer are stacked in this way, the sensitivity characteristics are improved, but on the other hand, the dark decay characteristics of the surface potential deteriorate, and the dark decay becomes faster. As a result, a small unevenness in the surface potential that occurs in the charging section becomes a large unevenness in the surface potential in the developing section after dark decay, and as a result, the density unevenness of the image becomes noticeable, and a good image cannot be obtained. There is a point.

Further, when the a-3i layer is laminated directly on the substrate, there is a problem that the adhesion between the layer and the substrate is insufficient and peeling occurs.

Therefore, an object of the present invention is to provide a highly reliable electrophotographic photoreceptor that can obtain high photosensitivity over the entire visible light range and that can also stably produce good images by improving the dark decay characteristics of the surface potential. It is about providing.

Means for Solving Problem C] The electrophotographic photoreceptor of the present invention has an atomic composition ratio of Si+ on a substrate.
The y value of -xCx is in the range of 0.2<x<0.5, and the periodic table II [a group elements are 1 to 10.000p
5. pm or Group Va elements. A first a-SiC layer containing oooppm, an a-8i layer, a second a-SiC layer having an atomic composition ratio of 31+-yC and a y value in the range of o<y<0.5, and an organic light It is characterized by sequentially stacking semiconductor layers, each of which is positively charged or negatively charged.

The electrophotographic photoreceptor of the present invention is also characterized in that the first a-3iC layer contains 0.01 to 30 atomic percent of oxygen and/or nitrogen.

The present invention will be explained in detail below.

1 and 2 show the layer structure of the electrophotographic photoreceptor of the present invention. In both cases, a first a-3iC layer 2, a-S
The i-layer 3 and the second a-3iC layer 4 are sequentially laminated, and an organic optical semiconductor layer 5 is further laminated. FIG. 2 shows another example, in which an inorganic protective layer 6 is provided on the organic optical semiconductor layer 5.
Laminate.

In the above layer structure, the first a-3iC layer 2 has a function of blocking injection of carriers from the substrate 1 when the photoreceptor is charged, and also improves the adhesion between the photosensitive layer and the substrate 1 so that the film can be peeled off. It has a function to prevent

The a-3i layer 3 and the second a-3iC layer 4 have a function of generating charges, and the organic optical semiconductor layer 4 has a function of transporting charges.

According to this layer structure, the second a-3iC layer 4 absorbs mainly the light on the short wavelength side of the light incident from the surface side of the organic optical semiconductor layer 50, and then the remaining light mainly on the long wavelength side is absorbed. a-
3i layer 3, and as a result, the photosensitivity is increased in the entire visible region.

First, for the first a-3iC layer 2, the range of element ratios is set as follows.

S1+-xCx 0°2<x<0.5 Preferably 0.3<x<0.5 If the y value is less than 0.2, carrier injection from the substrate 1 cannot be sufficiently prevented, and Dark decay characteristics cannot be improved, and adhesion to the substrate 1 cannot be sufficiently ensured. y
If the value is 0.5 or more, the a-3i layer 3 and the second a-
Photocarriers generated in the 3iC layer 4 do not flow smoothly to the substrate 1, resulting in decreased photosensitivity and increased residual potential.

Also, the thickness of the first (7) a-3iC layer 2 is 0.01 to 1
．． Own, preferably within the range of 0.05 to 0.5 μm, within this range good dark decay characteristics can be obtained,
The adhesion of the film is also improved.

Furthermore, the optical energy gap of the first a-3iC layer 2 is 0.0% compared to that of the a-Si layer 3. It is preferable to set a difference of IeV or more, preferably 0.2eV or more, so that injection of carriers from the substrate 1 can be effectively prevented.

Further, in the present invention, the first a-3iC layer 2 contains 1 to 10% of Group 1IIa elements of the periodic table. Another feature is that it contains OOOppm, preferably 100 to 5.000 ppm, which can prevent the injection of particularly negative charges among carriers from the substrate and improve the dark decay characteristic. If the content is less than 1 ppm, the above effects cannot be obtained, and 10. If it exceeds OOOppm, defects inside the layer will increase and the film quality will deteriorate, resulting in a decrease in surface potential and an increase in residual potential.

In addition, when incorporating the above-mentioned group 1 [[A group element, it is gradually reduced in the layer thickness direction from the substrate 1 to the photoreceptor surface, so that the photocarriers generated in the excitation layer, particularly the positive charges, smoothly flow toward the substrate side. In addition, carriers on the substrate side, especially negative charges, can be prevented from flowing into the photoreceptor layer, thereby further improving dark decay characteristics, further increasing photosensitivity, and further reducing residual potential. do. When a gradient distribution is provided in this way, the maximum content is also 1 to 10.0.
001) pm, preferably 100-5. OOOppm
Just do it.

The Group IIIa elements include B, A1. Ga, I
Among them, the B element is desirable because it has excellent covalent bonding properties and can sensitively change semiconductor properties, and also because it can provide excellent charging ability and photosensitivity.

Further, in the present invention, the first a-3iC layer 2 contains an element of Group Va of the periodic table in an amount of 5.000 ppm or less, preferably 3.
00-3. Another feature is that it contains OOOppm,
This makes it possible to prevent the injection of particularly positive charges among carriers from the substrate, and improve dark decay characteristics. If the content exceeds 5.000 ppm, defects inside the layer increase and the film quality deteriorates, resulting in a decrease in surface potential and an increase in residual potential.

In addition, when including the Group Va element, by gradually decreasing it in the layer thickness direction from the substrate 1 toward the surface of the photoreceptor, photocarriers, especially negative charges generated in the excitation layer can smoothly flow toward the substrate. Furthermore, carriers, particularly positive charges, on the substrate side can be prevented from flowing into the photoreceptor layer, thereby further improving dark decay characteristics, further increasing photosensitivity, and further reducing residual potential. When a gradient distribution is provided in this way, the maximum content is also 5.000 ppm.
Hereinafter, the content may preferably be set to 300 to 3,000 ppm.

The Group Va elements include N, P, As, Sb,
Although there is Bi, the P element is particularly desirable because it has excellent coexistence bonding properties and can sensitively change semiconductor properties, and also because it can provide excellent charging ability and photosensitivity.

In the a-3i layer 3, carriers are well excited by long wavelength light, and its photosensitivity can be increased.

For this purpose, it is desirable to set the thickness of the layer within the range of 0.05 to 5.0 μm, preferably 0.1 to 3.0 μm.

Moreover, the optical energy gap of this a-3i layer 3 (
When Eg opt (hereinafter abbreviated as E opt) is set within the range of 1.6 to 1.9 eV, good photoconductivity and high photosensitivity can be obtained.

Regarding the second a-SiC layer 4, its element ratio is set as follows.

St+-y Cao < y < o, s Preferably 0.05 < y < 0.4 Optimally 0.1 < y < 0.3 If the y value is 0.5 or more, photoconductivity becomes significantly lower, the excitation function of photocarriers is lowered, the photosensitivity is lowered, and the residual potential is also increased.

In addition, the thickness of the second (7) a-SiC layer 4 is o, 05 to 3
．． When set to 0 μm, preferably within the range of 0.1 to 2.5 μm, carrier excitation by short wavelength light is performed well,
Photosensitivity on the short wavelength side can be sufficiently increased.

Furthermore, E opt of the second a-SjC layer 4 is a-3
0. compared to i-layer 3. leV or more, preferably 0.2e
V or thicker (just set it so that it is, by doing this,
Light on the longer wavelength side reaches the a-Si layer 3 without being absorbed much.

In addition, in the case of a positively charged electrophotographic photoreceptor, the a-Si layer 3 and/or the second a-SiC layer 4 each contain 500 ppm or less, preferably 1100 pl, of Group Va elements of the periodic table.
) When contained within the following range, photosensitivity can be further enhanced. This group Va element includes N, P, and A.
S, Sb, Bi, or P elements are desirable because they have excellent covalent bonding properties and can sensitively change semiconductor properties, and also because they provide excellent charging ability and photosensitivity.

Furthermore, in the case of a negatively charged electrophotographic photoreceptor, the a-3i layer 3 and/or the second a-Si0 layer 4 each contain an element of group IV of the periodic table in an amount of 1 to too ppm, preferably 30 to
When the content is within the range of 300 ppm, the photosensitivity can be further increased. These group IIIa elements include B, A
I! + There are Ga-In, etc., but the B element has excellent covalent bonding properties and can sensitively change semiconductor properties, and in addition,
This is desirable because it provides excellent charging ability and photosensitivity.

Each of the above three types of layers 2. 3. 4 are amorphous layers, and their dangling bonds are terminated with hydrogen (H) elements or halogen elements. The a-3i layer 3 and the second a-Si0 layer 4 of those elements A (H or halogen)
It is preferable that the contents of each of these are set within the following ranges.

When expressed as a Z value by asi+-tAga (StC)+-tA, 0.05 < z < 0.5, preferably 0.1 < z < 0.45 The electrophotographic photoreceptor of the present invention is an organic photosemiconductor. Depending on the material selection of the layer 5, it can be of a negatively charged type or a positively charged type. That is, in the case of a negatively charged electrophotographic photoreceptor, an electron-donating compound is selected for the organic semiconductor layer 5, while in the case of a positively charged electrophotographic photoreceptor, an electron-withdrawing compound is selected for the organic semiconductor layer 5. To be elected.

The electron-withdrawing compound may have a high molecular weight, such as poly-
N-vinylcarbazole, polyvinylpyrene, polyvinylanthracene, pyrene-formaldehyde condensation polymer, etc., and low molecular weight ones include oxadiazole, oxazole, pyrazoline, triphenylmethane,
These include hydrazone, triarylamine, N-phenylcarbazole, and stilbene.These low-molecular substances include polycarbonate, polyester, methacrylic resin, polyamide, acrylic epoxy, polyethylene, phenol, polyurethane, butyral resin, polyvinyl acetate,
It is used after being dispersed in a binder such as urea resin.

Examples of the electron-withdrawing compound include 2.4.7-trinitrofluorenone.

The substrate 1 may be a metal conductor such as copper, brass, SOS, Af, or Ni, or an insulator such as glass or ceramics coated with a conductive thin film.

The substrate 1 may be a flexible conductive sheet in the form of a sheet, belt or web. Such sheets include l, Ni
1 Metal sheets such as stainless steel, or metals such as AI and Ni, or composite oxides of indium and tin: ITO (Indium Tin)
A transparent conductive material such as (Oxide) or an organic conductive material subjected to conductive treatment such as vapor deposition is used.

Furthermore, a protective layer 6 may be provided as shown in FIG. This layer 6 is an a-3i layer or an a-3iC layer (its elemental ratio is within the range of O≦a<0.95, preferably 0.5<a<0.95 with a value of 5ll-aC@). ), or the a-3i layer or the a-3iC layer may contain elements such as nitrogen or oxygen. By providing such a layer as the protective layer 6, wear resistance is improved compared to when the organic optical semiconductor layer is exposed on the surface. Moreover, since the surface of the protective layer (6) is chemically stable and does not undergo deterioration, image fading does not occur during long-term use.

Furthermore, when the first a-3iC layer 2 contains the element B of oxygen and/or nitrogen in the total amount as shown below, the adhesion to the substrate 1 and the release from the substrate 1 are improved compared to the case where the element B is not contained. The ability to stop carrier injection is enhanced.

(Sir, -*C,)+-bBb 0.0001<b<0.3 Preferably 0.001<b<0.1 Next, a method for manufacturing the electrophotographic photoreceptor of the present invention will be described.

First a-3iC layer 2, a-3i layer 3 and second a-s
To form the IC layer and the protective layer 6 made of a-3i, a-3iC, amorphous Si-C-N elements, Si-C-0-N elements, etc., glow discharge decomposition method,
There are thin film forming methods such as an ion blasting method, a reactive sputtering method, a vacuum evaporation method, and a CVD method.

When forming a SiC layer using glow discharge decomposition method, S
A gas containing an i element and a gas containing a C element are combined, and this mixed gas is subjected to plasma decomposition to form a film.

This Si element-containing gas includes SiHa, Si2Hs,
SisHs.

SiF4. There are SiC14, SiHC1s, etc., and C element-containing gases include CH4, C2H4, C2H2, C
There are aH8 and the like, and C2H2 is particularly desirable because it can provide high-speed film formation.

The organic photosemiconductor layer is formed by a dip coating method or a coating method. According to the latter coating method, a photosensitive material dispersed in a solvent is applied using a coater, and then hot air drying is performed.

Thus, according to the electrophotographic photoreceptor of the present invention, since the carrier excitation layer has a tandem structure in which the a-3iC layer and the a-3i layer are laminated, light incident from the organic photosemiconductor layer 5 side is transmitted to the second layer. The a-3iC layer 4 mainly absorbs light on the short wavelength side, and then the a-3i layer 3 absorbs mainly the light on the long wavelength side that has passed through the layer 4.
Compared to a single excitation layer, the photosensitivity is increased over the entire visible region and the residual potential is reduced.

In addition, as shown in Fig. 3, the a-3i layer and the a-3i layer are directly placed on the substrate.
A known electrophotographic photoreceptor R having a structure in which SiC layers are laminated
If so, the a-3i layer cannot effectively block carrier injection from the substrate, and the injected carriers accelerate the dark decay of the surface potential. The decrease in surface potential increases until

Further, small charging unevenness in the charging section becomes large unevenness in surface potential in the developing section, and therefore, unevenness in image density becomes large, so there is a problem in that it is difficult to obtain good image characteristics. Furthermore, if the dark decay is fast, fluctuations in the surface potential at the developing area tend to increase, making it difficult to stably obtain images of good quality during continuous use. On the other hand, in the electrophotographic photoreceptor T of the present invention, the first a-8i layer has a higher dark resistance and a larger Eg Opt than the a-3i layer.
Since the C layer 2 is provided and can effectively block carrier injection from the substrate 1 and slow dark decay, the above-mentioned problems can be improved.

〔Example〕

Next, examples of the present invention will be described.

(Example 1) Using a capacitively coupled glow discharge decomposition apparatus for producing an electrophotographic photoreceptor, a first a
-SiC layer 2, a-Si layer 3 and second (7) a-3iC
Layers 4 were laminated in sequence.

Next, an organic optical semiconductor layer 5 was formed to a thickness of 15 μm.

In its formation, 2.4.7-trinitrofluorenone was dissolved in 1.4-dioxane solvent, polyester resin (Refsan-LS2-11) was added, and ultrasonic dispersion was performed for 40 minutes. . The resulting solution was applied using a bar coater and then dried with hot air at 80''C.

[Left below] In the positively charged electrophotographic photoreceptor thus obtained,
When the B element content of the first a-3iC layer was measured using a secondary ion mass spectrometer, it was 1.000 ppm,
In addition, the carbon content ratio (X value and y value), H content ratio (Z value), and Pg opt of each layer were set to XJ1!
(αhν)x of the transmitted light spectrum measured by microanalysis and infrared absorption method and by visible light spectrometer
As a result of plotting /2 vs. hv, the results shown in Table 1 were obtained.

Further, in producing the electrophotographic photoreceptor of this example, the first a-3iC layer and the a-3i layer were not formed, and the second a-3iC layer was not formed.
Comparative Example A was obtained by forming only the C layer and forming the rest in the same manner as in this example.

Furthermore, in producing the electrophotographic photoreceptor of this example, the first a-3iC layer was not formed, and the a-3i layer and the second a-3iC layer were formed.
Comparative Example B was prepared by forming only the 3iC layer and forming the rest in the same manner as in this example.

When the spectral sensitivities of the electrophotographic photoreceptor of the present invention and Comparative Example A were measured, the results shown in FIG. 4 were obtained. In the figure, the horizontal axis is the wavelength, and the vertical axis is the photosensitivity, and the change in surface potential in response to exposure to light of 0.3 μW/cm2 at each wavelength was measured using a surface potential meter with a light transmission probe. It was determined by the reciprocal of the exposure amount required to reduce the surface potential by half.

As is clear from the results shown in FIG.
It can be seen that the photosensitivity is higher on the long wavelength side of 600 nm or more compared to the above.

In addition, the photosensitivity of Comparative Example B was similar to that of this example, but on the other hand, when we followed the course of the surface potential in the dark after charging, we found that the surface potential was higher than that of the photoreceptor of this example. It can be seen that the dark decay is fast, the charging is low, and the potential unevenness is large.

Furthermore, when the photoreceptor of this example and Comparative Example B were left in an environment of 35°C and 95% RH for 24 hours, no change was observed in the photoreceptor of this example, whereas in Comparative Example B, the substrate It was also confirmed that the film peeled off from the a-Si layer, and that there was a problem with the adhesion of the film.

Furthermore, in producing the photoreceptor of this example, the first a-
B2H and gas were not introduced during the formation of the 3iC layer, and the other conditions were set to be exactly the same, thereby producing a positively charged electrophotographic photoreceptor with a first a-SiC layer that does not contain B element. was created.

When the characteristics of this electrophotographic photoreceptor were evaluated, the spectral sensitivity on the long wavelength side of 600 nm or more was found to be 1 in this example.
However, compared to the photoreceptor of this example, the dark decay of the surface potential was about 20% faster, the charging was lower, and the potential unevenness was larger.

(Example 2) In producing an electrophotographic photoreceptor similar to (Example 1),
82H@ By changing the gas flow rate and changing the B element content of the first a-3iC layer 2, ten types of photoreceptors A to J shown in Table 2 were manufactured, and the dark decay of each photoreceptor was , photosensitivity and residual potential were evaluated. In addition, in the dark decay, photosensitivity, and residual potential in the table, ◎ indicates the case where the best results were obtained, O indicates the case where somewhat excellent results were obtained, and △ indicates the case where slightly inferior results were obtained. This is the case when it is obtained.

Table 2 *marks are outside the scope of the present invention.

As is clear from the results shown in Table 2, it can be seen that photoreceptors B to I are excellent in all of dark decay, photosensitivity, and residual potential.

(Example 3) The first a-SiC layer 2, the a-Si layer 3, and the 2 aSiCS
Four iC layers were laminated.

Next, the organic optical semiconductor layer 5 was formed to a thickness of 15 μm in the same manner as in (Example 1).
It was formed with

[Margin below]

In the electrophotographic photoreceptor thus obtained, the first a-
When the B element content and the total content of O and N elements in the 3iC layer were measured using a secondary ion mass spectrometer, they were 1.000 ppn+ and 4 atomic %, respectively.

Further, in producing the electrophotographic photoreceptor of this example, the first a-3iC layer and the a-3i layer were not formed, and the second a-3iC layer was not formed.
Comparative Example C was obtained by forming only the C layer and forming the rest in the same manner as in this example.

Furthermore, in producing the electrophotographic photoreceptor of this example, the first a-3iC layer was not formed, and the a-Si layer and the second a-3iC layer were formed.
A 3iC layer was formed in the same manner, and the others were formed in the same manner as in this example to provide a comparative example.

When the spectral sensitivities of the electrophotographic photoreceptor of the present invention and Comparative Example C were measured, the same results as shown in FIG. 4 were obtained.

In addition, the photosensitivity of the comparative example was similar to that of this example, but on the other hand, when we followed the progress of the surface potential in the dark after charging, the surface potential was higher than that of the photoreceptor of this example. It can be seen that the dark decay is fast, the charging is low, and the potential unevenness is large.

Furthermore, when the photoconductor of this example and the comparative example were left in an environment of 35°C and 95% RH for 24 hours, no change was observed in the photoconductor of this example, while the comparison example It was also confirmed that the film peeled off from the a-3i layer, and there was a problem in the adhesion of the film.

Furthermore, in producing the electrophotographic photoreceptor of this example, B, H, gas, and NO gas were not introduced during the formation of the first a-SiC layer, and the other conditions were set to be exactly the same. A positively charged electrophotographic photoreceptor was manufactured, which included a first a-3iC layer in which elements B, B, O, and N were not combined.

When the characteristics of this electrophotographic photoreceptor were evaluated, the spectral sensitivity on the long wavelength side of 600 nm or more was almost the same as the photoreceptor of this example, but on the other hand, compared to the photoreceptor of this example, The dark decay of the surface potential was about 25% faster, the charging was low, and the potential unevenness was large.

(Example 4) In producing an electrophotographic photoreceptor similar to (Example 2),
B2H, by changing the gas flow rate and NO gas flow rate, the first a
Eight types of photoreceptors of -R as shown in Table 4 were prepared by changing the B element content and the total content of 0 element and N element in the -3iC layer, and the dark decay, photosensitivity, and The residual potential was evaluated.

[Margin below]

As is clear from the results shown in Table 4, it can be seen that photoreceptors L to Q are excellent in all of dark decay, photosensitivity, and residual potential.

(Example 5) A first a-
A SiC layer 2, an a-3i layer 3, and a second a-Si0 layer 4 were sequentially laminated.

Next, an organic semiconductor layer 5 was formed to a thickness of 15 μm.

According to its formation, hydrazone is dissolved in a solvent of 1,4-dioxane, and then polyester resin (Refsan-LS2-11) is added in the same weight as hydrazone, and
Ultrasonic dispersion was performed for 40 minutes, and the resulting solution was applied using a bar coater, followed by hot air drying at 80°C.

[Margin below]

No. table *marks are outside the scope of the present invention.

In the positively charged electrophotographic photoreceptor thus obtained,
P element content of first a-3iC layer and second a-3i
When the B element content of the C layer was measured using a secondary ion mass spectrometer, it was found to be 2.000 ppm and 1100 ppm, respectively.
It was p.

Further, in producing the electrophotographic photoreceptor of this example, the first a-3iC layer and the a-3i layer were not formed, and the second aSiC layer was not formed.
Comparative Example E was prepared by forming only the layer and forming the rest in the same manner as in this example.

Furthermore, in producing the electrophotographic photoreceptor of this example, the first a-3iC layer was not formed, and the a-3i layer and the second a-3iC layer were formed.
Comparative Example F was obtained by forming only the 3iC layer and forming the others in the same manner as in this example.

When the spectral sensitivities of the electrophotographic photoreceptor of the present invention and Comparative Example E were measured, the results shown in FIG. 4 were obtained.

As is clear from the results shown in FIG.
It can be seen that the photosensitivity is higher on the long wavelength side of 600 nm or more compared to the above.

In addition, the photosensitivity of Comparative Example F was similar to that of this example, but on the other hand, when we followed the progress of the surface potential in the dark after charging, we found that the surface potential was higher than that of the photoreceptor of this example. It can be seen that the dark decay is fast, the charging is low, and the potential unevenness is large.

In addition, the photoreceptor of this example and Comparative Example F were tested at 35°C, 95% RF (
When the photoreceptor of this example was left for 24 hours in an environment of It was also confirmed that he had a sexual problem.

Furthermore, in producing the photoreceptor of this example, the first a-
During the formation of the 3iC layer, PH and gas were not introduced, and the other conditions were set to be exactly the same, thereby producing a negatively charged electrophotographic photoreceptor having the 10a-3iC layer containing no B element. .

When the characteristics of this electrophotographic photoreceptor were evaluated, the spectral sensitivity on the long wavelength side of 600 nm or more was almost the same as the photoreceptor of this example, but on the other hand, compared to the photoreceptor of this example, The dark decay of the surface potential was about 20% faster, the charging was low, and the potential unevenness was large.

In producing an electrophotographic photoreceptor similar to (Example 5),
By changing the Pit gas flow rate, P of the first a-3iC layer 2 is
Ten types of Alco photoreceptors shown in Table 6 were prepared with different element contents, and the dark decay, photosensitivity, and residual potential of each photoreceptor were evaluated.

[Margin below]

Table 6 *marks are outside the scope of the present invention.

As is clear from the results shown in Table 6, it can be seen that photoreceptors A to A are excellent in all of dark decay, photosensitivity, and residual potential.

(Example 6) Using a capacitively coupled glow discharge decomposition apparatus for producing an electrophotographic photoreceptor, the first a
-3iC layer 2, a-3i layer 3 and second a-3iC layer 4
were sequentially stacked.

Next, the organic optical semiconductor layer 5 was formed to a thickness of 15 μm in the same manner as in (Example 4).
It was formed with.

[Margin below]

In the negatively charged electrophotographic photoreceptor thus obtained,
When the P element content and the total content of each 0°N element in the first a-3iC layer were measured, they were each 2.000 ppp.
m was 4 at%.

Further, in producing the electrophotographic photoreceptor of this example, the first a-3iC layer and the a-3i layer were not formed, and the second aSiC layer was not formed.
Comparative Example G was prepared by forming only the layer and forming the others in the same manner as in this example.

Furthermore, in producing the electrophotographic photoreceptor of this example, the first a-3iC layer was not formed, and the a-3i layer and the second a-3iC layer were formed.
Comparative Example H was prepared by forming the SiC layer in the same manner as in this example, and forming the others in the same manner as in this example.

When the spectral sensitivities of the electrophotographic photoreceptor of the present invention and Comparative Example G were measured, the same results as shown in FIG. 4 were obtained.

In addition, the photosensitivity of Comparative Example H was similar to that of this example, but on the other hand, when we followed the progress of the surface potential in the dark after charging, we found that the surface potential was higher than that of the photoreceptor of this example. It can be seen that the dark decay is fast, the charging is low, and the potential unevenness is large.

It was also confirmed that film peeling occurred between the photoreceptor of this example and the a-3i layer of Comparative Example H at 35° C. and 95% RH, and that there was a problem in film adhesion.

Furthermore, in producing the electrophotographic photoreceptor of this example, PH2 gas and NO gas were not introduced during the formation of the first a-3iC layer, and the other conditions were set to be exactly the same, whereby P element, The first a- which does not contain 0 element and N element
A positively charged electrophotographic photoreceptor including 3iCN was produced.

When the characteristics of this electrophotographic photoreceptor were evaluated, it was found that the spectral sensitivity on the long wavelength side of 600 nm or more was almost the same as the photoreceptor of this example, but on the other hand, the surface potential was higher than that of the photoreceptor of this example. The dark decay was about 20% faster, the charge was low, and the potential unevenness was large.

(Example 7) In producing an electrophotographic photoreceptor similar to (Example 5),
By changing the PH, gas flow rate and NO gas flow rate, the first a-
Eleven types of photoreceptors shown in Table 8 were prepared by changing the P element content and the total content of 0 element and N element in the 3iC layer, and the dark decay, photosensitivity, and residual content of each photoreceptor were measured. The potential was evaluated.

[Margin below]

No. table *marks are outside the scope of the present invention.

As is clear from the results shown in Table 8, it can be seen that the photoreceptor ST is excellent in all of dark decay, photosensitivity and residual potential.

〔Effect of the invention〕

As described above, according to the present invention, high photosensitivity can be obtained over the entire visible light range, the residual potential is small, and there is little density unevenness in the image, which makes it possible to stably produce good images. A high-performance and highly reliable electrophotographic photoreceptor could be provided.

Furthermore, in the electrophotographic photoreceptor of the present invention, the film has excellent adhesion to the substrate, and reliability is also improved in this respect.

[Brief explanation of drawings]

1 and 2 are cross-sectional views showing the layer structure of the electrophotographic photoreceptor of the present invention, FIG. 3 is a diagram illustrating attenuation of surface potential, and FIG. 4 is a diagram illustrating photosensitivity with respect to wavelength. . 2: First amorphous silicon carbide layer 3: Amorphous silicon layer 4: First amorphous silicon carbide layer 5: Organic optical semiconductor layer 6: Protective layer

Claims (3)

[Claims] (1) x with an atomic composition ratio of Si_1-_xC_x on the substrate
The first element has a value in the range of 0.2<x<0.5 and contains 1 to 10,000 ppm of Group IIIa elements of the periodic table.
forming an amorphous silicon carbide layer of the first
An amorphous silicon layer, a second amorphous silicon carbide layer having an atomic composition ratio in the range of 0<y<0.5 as a y value of Si_1_-_yC_y, and an organic optical semiconductor layer were sequentially laminated on the amorphous silicon carbide layer of An electrophotographic photoreceptor characterized by: (2) First amorphous silicon having an atomic composition ratio in the range of 0.2<x<0.5 in the x value of Si_1_-_xC_x and containing 5,000 ppm or less of Group Va elements of the periodic table on the substrate. A carbide layer is formed on the first amorphous silicon carbide layer, and an amorphous silicon layer with an atomic composition ratio of Si_1_-_yC_y is formed on the first amorphous silicon carbide layer.
An electrophotographic photoreceptor characterized in that a second amorphous silicon carbide layer and an organic optical semiconductor layer having values in the range of 0<y<0.5 are sequentially laminated. (3) The electrophotographic photoreceptor according to claim 1 or claim 2, wherein the first amorphous silicon carbide layer contains 0.01 to 30 atomic percent of oxygen and/or nitrogen.