JPS63188157A - Photosensitive body - Google Patents

Abstract

PURPOSE:To control photofatigue and photodeterioration and to improve durability and color reproducibility by incorporating a selective light absorptive material consisting of a dye into an insulating layer and satisfying specific conditions. CONSTITUTION:The selective light absorptive material consisting of the dye is incorporated into at least the insulating layer of the respective layers of a photosensitive body having a photosensitive layer and the insulating layer as the uppermost layer and the equation is satisfied. The thickness of an electric charge generating layer is preferably 0.01-10mum, more preferably 0.2-5mum. Uniform formation of the charge generating layer tends to be difficult, if the thickness is <0.01mum. Electrophotographic characteristics tend to degrade, if the thickness exceeds 10mum. The thickness of an electric charge transfer layer is preferably 5-50mum, more preferably 8-20mum. The color sensitivity particularly in blue and yellow wavelength regions or red wavelength region is thereby sufficiently and accurately controlled to satisfy the required color reproducibility and the UV resistance is improved, by which the stability and durability are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a photoreceptor, 4! This relates to an IFK electrophotographic photoreceptor.

Conventional technology Conventionally, inorganic photoconductive materials such as selenium, zinc oxide, titanium oxide, and cadmium sulfide have been mainly used as photosensitive materials for electrophotographic photoreceptors. Research and development is also actively underway.

On the other hand, photosensitive materials using organic photoconductive substances (OPC) are generally less toxic than inorganic photoconductive substances, and are advantageous in terms of flexibility, lightness, film formability, stability, etc. For this reason, it has been attracting attention recently.

In any electrophotographic photoreceptor, a functionally separated photoreceptor has the functions of charge generation and transport separated in each layer, and each function can be set independently. ,
This is advantageous in terms of photoreceptor design because it provides a wider range of options.

In addition, the functionally separated desensitizer can improve the electrophotographic characteristics and is excellent in terms of sensitivity, repeatability, mechanical strength, etc.

Recently, electrophotographic photoreceptors using various charge-generating substances have been actively developed, and these charge-generating substances have unique spectral sensitivity characteristics. First, they are selectively used depending on the purpose of use, that is, the light source, the type of document, etc. For example, in a copier that uses white light such as a normal A light source or a fluorescent lamp, the photoreceptor uses a charge-generating material that is sensitive in the visible region, but in a printer that uses a He-Ne laser as a light source, the oscillation wavelength is 632.8 n
Photoreceptors having a sensitivity around 780 nm are used in printers using a semiconductor laser as a light source, and the type of photoreceptor is selected depending on the purpose.

Now, with the above-mentioned copying machine that uses white light as a light source, it is necessary to faithfully reproduce the original original, and even if the original is not only black but also chromatic colors such as red and blue, it can be used for the purpose. Copies must be reproduced accordingly. For example, there are demands for reproducibility of red stamps, reproducibility of blue ink, reproducibility of thermal paper, etc. For this purpose, for example, in order to reproduce red color, the wavelength must be 600 nm or more, and in the case of yellow, it must be 570 to 5 nm.
90 nm, 500-570 nm for green, and 450-500 nm for blue. Either there is no sensitivity in the wavelength range, or the sensitivity in these wavelength ranges is lower than that in other wavelength ranges. It must be something that you have.

However, as mentioned above, the charge-generating substance has unique spectral sensitivity characteristics, satisfies electrophotographic characteristics,
It is difficult to find a charge generating material that can reproduce dark brown originals to a degree suitable for the purpose of copying.

For this reason, for example, in order to improve the reproducibility of red, white light is used and a red cut filter (cyan filter) is installed in the optical path, or a special light source is used (a fluorescent lamp that does not emit light in the red region). For example, e-54>shi covers the above-mentioned problems on the machine side.Research has also been conducted in which the photoreceptor itself is given the role of a filter.

Also, for example, a diode laser is installed at the terminal in the evening on Mpi Island.
A printer that uses a light source as a light source is used.

The electrophotographic photoreceptor incorporated into such a printer must have high sensitivity in the near-infrared region of 760 nm or more, which is the oscillation wavelength range of a diode laser.

Further, development is progressing on devices that have a diode laser-based printer with a copying function using white light as a light source.

In this case, the photoreceptor must first have high sensitivity in the near-infrared region of 760 nm or more, as described above, in order to adapt to the printer function, and also reproduce red, for example, in order to adapt to the copy function. 600-760nm for yellow, 570-590nm for yellow, 500nm for green
~570 nm, and in the case of blue, 450 to 500 nm, the spectral sensitivity characteristics must be either no sensitivity, or the sensitivity in these wavelength ranges is lower than the sensitivity in other wavelength ranges. However, in electrophotographic photoreceptors that use organic photoconductive substances that have high sensitivity in the near-infrared region, the absorption spectrum of the charge-generating material is widely distributed from the visible region to the near-infrared region, and the electrophotographic photoreceptor has high sensitivity even in the visible region. This makes it difficult to reproduce red and blue colors.

That is, there is also a demand for the development of an electrophotographic photoreceptor that can be applied to an apparatus having both the printer function and the copying function using white light as a light source.

For example, Japanese Patent Application Laid-Open No. 60-233655 discloses that a dye that absorbs the corresponding wavelength of lonm or more or 580 nm or more is contained in the photosensitive layer in consideration of red reproducibility and yellow reproducibility. Also, JP-A-60-22035
No. 6 and No. 60-220357 disclose that in order to improve blue reproducibility or red reproducibility, a pigment that cuts the corresponding wavelength component is contained in an intermediate layer between the photosensitive layer and the substrate. .

However, in any of the known techniques, the controllability of photosensitivity as described above, especially in terms of blue reproducibility and red reproducibility, is not sufficiently realized, and the short wavelength side of organic photoconductive materials (e.g. dibrome anthron) In parallel, we need to effectively control the spectral sensitivity of organic photoconductive materials to suppress yellow reproduction by effectively controlling the yellow wavelength region, and furthermore, how to control the spectral sensitivity of organic photoconductive materials so as not to impair their original sensitivity characteristics. It was insufficient in terms of implementation, etc. Furthermore, color sensitivity control must be achieved not only by simply cutting wavelength components, but also by controlling optical fatigue and optical deterioration of the photoreceptor and increasing its durability.

C6 Purpose of the Invention The purpose of the present invention is to be able to sufficiently and accurately control color sensitivity, especially in the blue and yellow wavelength range or red wavelength range, and to achieve ultraviolet resistance so as to satisfy the required color reproducibility. An object of the present invention is to provide a photoreceptor with improved stability and durability.

20 Structure of the invention and its effects, that is, the present invention provides a photoreceptor having a photosensitive layer and an insulating layer as an uppermost layer, wherein at least five of the five insulating layers of each layer selectively absorb light comprising a dye. Contains sexual substances,
and relates to a photoreceptor having the following formula in its groove.

λ4 is the maximum absorption wavelength of the selective light-absorbing material (unit: nm); λ4 is the maximum absorption wavelength of the selective light-absorbing material (unit: nm); Ad(λwax) is the light absorption rate of the selective light-absorbing material when λ≦,8. ] The photoreceptor has an insulating layer provided on the photosensitive layer. As an example of the operation process of a photoreceptor provided with this insulating layer, first, if necessary, a positive or negative primary charge is performed at the same time as the entire surface is exposed, and then a polarity opposite to that of the above-mentioned charging and/or (Note 2) A primary electrostatic latent image is formed by alternating current charging and simultaneous image exposure, and then a second electrostatic latent image is formed on the surface of the photoreceptor by full exposure. (potential pattern).

The presence of the insulating layer makes it possible to use photoreceptors that cannot be practically used in the normal Carlson process, since the surface strength of the underlying photosensitive layer is weak, and also completely eliminates toxic substances. It becomes possible to use it. In addition, various applications can be made depending on the operating process.

For example, it is possible to perform multicolor copying by dividing the final full-surface exposure into several steps according to a prescribed image pattern.

Furthermore, it is possible to control the potential by setting the conditions for primary charging and secondary charging, and if the width of the potential contrast (difference between black and white) and its absolute value are a
) K As shown in FIG. A photosensitive layer 4 is configured by providing a carrier generation layer 2 containing
Furthermore, an insulating layer 5 as the outermost layer is provided thereon to constitute an electrophotographic photoreceptor.

Furthermore, the photosensitive layer can be composed of a single layer as shown in FIG. 1(b).

Note that the photosensitive layer is made of ZnO1CdS, Ss/Ta
.

Any of inorganic photoreceptors such as A@, Se, a-8i, and other organic photoreceptors can be used.

When the charge carriers to be transported are holes, and when the primary charge is negatively charged electrons, it is possible to operate with the primary charge being positively charged.

In such a photoreceptor, a brominated anthanthrone pigment (polycyclic quinone pigment) having the structure shown below, for example, can be used as a high-grade organic pigment in the photosensitive layer. This pigment has higher sensitivity than conventional inorganic particles or perylene pigments, and can provide a uniform photosensitive layer with good scratch resistance.

Carrier-generating substances that can be used, including such organic pigments, exhibit a spectral sensitivity distribution as shown by CGM in FIG. 2 [However, λ1. ! is the maximum absorption wavelength (unit: nm) of the charge generating substance in the charge generating layer.

λ::萱 is 540 nm for organic pigments such as those mentioned above.
In other words, it is included in the yellow region (500 nm or more).

) is・also・600n with a longer wavelength than this 200M
Since the red light absorption rate suddenly decreases near m116 and there is no red sensitivity, the originally required red light cut can be sufficiently achieved and the red color reproducibility is good. However, a photoreceptor using this charge generating material has the following problems when using a light source A consisting of a halogen lamp.

(a) Since there is absorption in the blue wavelength range (400 to 500 nm) or the cyan wavelength range (400 to 600 nm), the reproducibility of blue or cyan deteriorates.

(b) Concomitantly, since short-wavelength light is absorbed, ultraviolet light components are also absorbed, which rapidly increases the speed of photofatigue and photodeterioration of the photosensitive layer.

(C) is sensitive to yellow light, but the proportion is still insufficient (because there is no sensitivity above 560 nm),
Yellow is reproduced to some extent, resulting in yellow fog.

After considering the above-mentioned problems (a) to (c), the present inventor discovered that a light-absorbing material made of a dye having a spectral sensitivity distribution as shown in the broken line (d) l in Fig. 2 was used as an insulating layer. It has been found that extremely excellent results can be obtained when the mixture is contained [provided that λ≦,! is the maximum absorption wavelength (unit: nm) of the dye.

Ad(200M) is the light m of the dye at λcoMK
&X! mA! Absorption rate. Ad(λ
! , x) Table λKaaX Light absorption rate of the dye in IIC].

Here, based on the present invention, it is essential to satisfy the following formula.

10nm≦1(λ蕃−λmax)l≦(λ蕃−200n
m) That is, the dye contained in the insulating layer has wavelength selectivity and absorbs light components on the relatively short wavelength side, and prevents or controls this component light from reaching the charge generation layer (i.e., prevents or controls the component light from reaching the charge generation layer). (color control). At that time, preferably 20 nm or more,
Furthermore, if it is not (preferably similar to 30ni), it will interfere with the original absorption of the charge generating substance, resulting in poor sensitivity and will also absorb the yellow wavelength region, and it will also cut short wavelength components to improve blue reproducibility. In order to increase ΔλmkN, it is necessary to increase the amount of dye added, but this deteriorates the electrophotographic characteristics and is inappropriate. Therefore, Δλwax is 1 (λ: North - 200am.

It is necessary to set it to below, preferably to set it to 300 nm or less, and to set it to 150 nm or less more preferably. In addition, if the light absorption rate of the dye is not adjusted to the above value (or less than 0.3, more preferably less than 0.2), it will interfere with the original light absorption of the charge-generating substance, resulting in the generation of photocarriers and, ultimately, the light absorption. This will affect sensitivity.

As described above, by setting the above-mentioned Δλwax and ABS ratio within a specific range based on the present invention, as shown in FIG. The charge generating material actually has a spectral sensitivity distribution. Therefore, the following remarkable advantages can be exhibited.

(People) Since the above dye can effectively cut blue light, it is possible to bring the potential of the blue (and cyan) portion of the photoreceptor closer to the black paper potential, improving blue reproducibility (improving blue density). It becomes possible.

(B) and L can cut short wavelength components including blue light, resulting in good ultraviolet resistance and stability against ultraviolet light.

(C) Furthermore, since the above dye functions as a so-called yellow dye, it can increase sensitivity to yellow light, suppress yellow reproduction, and prevent capri caused by it. That is, the potential of the yellow component of the photoreceptor can be brought close to the white paper potential so that the yellow component does not appear.

As another example, when a long wavelength sensitive charge generating substance such as a disazo compound or a trisazo compound is used, contrary to the above-mentioned compounds, it has excellent reproducibility of blue color and non-reproducibility of yellow color, but Reproducibility is insufficient. In order to improve this red reproducibility, a red absorbing dye is added to control color sensitivity.

For example, when a disazo pigment such as is used as a charge generating substance,
The maximum absorption wavelength is λrmhx = 630 nm, and it is sensitive to red light, resulting in poor reproducibility of red stamps, etc.

In such a case, contrary to the above case, λwax is placed on the longer wavelength side than the λ upper mold, as shown by the dashed line (d) in Figure 2.
(However, 1, for example, 200M is 6
00 in). Similarly, Δλtmax at aax for this dashed line (d) is preferably 300 nm or less, and more preferably 150 nm or less, as is the case with the dashed line 1/, +ld).

Note that it is also effective to include this dye not only in the insulating layer but also in the photosensitive layer (in the case of a functionally separated photoreceptor, one or both of the charge generation layer and the charge transport layer).

Usable dyes can be selected depending on the type of charge generating substance. Dyes that can be used in the present invention include nitrone dyes, nitro dyes, azo dyes, stilbene dyes, diphenylmethane dyes, triarylmethane dyes, xanthine dyes,
Acridine dye, xanthine dye, quinoline dye, (poly)methine dye thiazole dye, indamine dye, indophenol dye, azine dye, oxazine dye, thiazine dye, sulfur dye, aminoketone dye, oxyketone dye, anthoquinone dye, indigoid dye , phthalocyanine dyes, pyrazolone dyes, piri IJ Pi dyes, shea dyes, etc. may be used, but the dyes are not limited thereto.

For example, the Pigment Handbook (Kodansha Scientific, 1st edition published in 1986), Color Index (C
o1or Index ) (Society Op O
Society of Diamonds and Colorists
Dyers and Colourists) 3rd edition, 7 expanded volumes, 1975, or the dyes described in the Dye Handbook can be used.

(Naphthol Green B) nitro dye (Naphthol Yellow S) azo dye (amaranth) (fluorescein) (clinophenine G) Eitsushi-wa l Eigo (Auramine) (-Rakite Green) (Rhodamin B) (Acridine Orange R) N.H.

(Rivanol) (Quinoline Yellow) (Atrazonink FG) (Thioflapine T) Indophenol dye Azine dye (Sacnin T) Glossine) (Galocyanine) ヱ1koυrihiki1 (Methylene blue) - (Sulfur Black B) (Herringdon Yellow〇〇) (Su7 Tazarin) Anthraquinone dye (Alizarin Cyanine Green G) (Indigo) (Bontamin Faster; As8GL)! L OOH (Tartrazine) (Arylthiapyrylium salt) (Binacia tool) In particular, in the case of electrophotographic photoreceptors that use polycyclic quinone pigments as charge-generating substances, it is possible to reproduce blue and yellow colors. It is preferable to use pyrazolone dyes for the purpose of not reproducing.

Next, as carrier generation and quality suitable for the present invention, as long as it absorbs visible light and generates free carriers,
Both inorganic pigments and organic dyes can be used.

In addition to inorganic pigments such as amorphous selenium, trigonal selenium, selenium-arsenic alloy, selenium-tellurium alloy, cadmium sulfide, cadmium selenide, cadmium selenide sulfide, mercury sulfide, lead oxide, lead sulfide, the following representative examples Organic pigments such as those shown may also be used.

(1) Azo pigments such as monoazo pigments, polyazo pigments (diazo pigments, trisazo pigments, etc.), metal complex azo pigments, pyrazolone azo pigments, stilbene azo pigments, and thiazole azo pigments (2) Perylenic anhydride, perylenic acid imide, etc. perylene pigments (3) anthraquinone derivatives, anthanthrone derivatives, dibenzpyrenequinone derivatives, pyrazolone dyes,
Anthraquinone or polycyclic quinone pigments such as violanthrone derivatives and isoviolanthrone conductors (4) Indigoid pigments such as indigo derivatives and thioindigo derivatives (5) Heptalocyanine pigments such as metal phthalocyanine and metal-free phthalocyanine C6) Diphenylmethane pigments, triphenylmethane pigments, xanthine pigments, and acridines ``0''''5
°″′″′1″ 4 (7) Quinoneimine pigments such as azine pigments, oxazine pigments, and l-azine pigments (8) Methine pigments such as cyanine pigments and azomethine pigments (9) Quinoline pigments (10) Nitro pigments (11) Nitroso pigments (12) Benzoquinone and naphthoquinone pigments (1
3) Naphthalimide pigments (14) Perinone pigments such as bisbenzimidazole derivatives, but preferably azo or polycyclic quinone pigments having an electron-withdrawing group, with an average particle size of 2 μm or less, especially 1 μm
The following granules are preferably dispersed and contained in the photosensitive layer. In this case, the electrophotographic properties of the photoreceptor, such as photosensitivity, memory phenomenon, and residual potential, become more excellent.

Examples of carrier-generating substances suitable for the present invention include the compounds described in Japanese Patent Application No. 60-297503.

In addition, as inorganic materials, vacuum-deposited amorphous selenium alloy and B-5iQ6 andlo r
or a-8i: Handlor x (where X is a halogen element and contains an IorV group element. It may also contain oxygen) or Cd8%ZnO
It is best to use a dispersed coating.

Selenium and selenium alloys, CdS.

There are no particular restrictions on inorganic substances such as Zn0a-8i or organic substances, but examples of organic substances include oxazole derivatives,
Oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidasilone derivatives imidazolidine derivatives, bisimidazolidine derivatives, styryl compounds, hydrazone compounds, pyrazoline derivatives, oxacilone derivatives, benzothiazolumi 1J compound, benzimidazole rust conductors, quinazoline derivatives, benzofuran derivatives, acridine derivatives,
Phenazine derivatives, aminostilbene derivatives, poly-N
-vinylcarbazole, poly-1-vinylpyrene, poly-9-vinylanthracene, etc.

However, it is preferable to use a material that not only has an excellent ability to transport holes and/or electrons generated during light irradiation but also is suitable for combination with the carrier-generating substance. As the carrier transporting substance, for example, the compounds described in Japanese Patent Application No. 60-297503 are used.

Examples of inorganic materials include those containing CdS and ZnO in the photosensitive layer, a-8e/Te alloy, and a-As/
Vacuum-deposited Se alloy and a-8iC: Handl
or

As described above, the photoreceptor of the present invention has a photosensitive layer on a conductive substrate, and an insulating layer containing a selective light-absorbing substance (dye) is laminated as the uppermost layer. The photosensitive layer is formed by providing a subbing layer or an intermediate layer on a substrate, if necessary, and further forming a charge generating layer, if necessary. The charge generation layer is composed of a charge generation substance and, if necessary, a binder resin, a charge transport substance and an additive. The charge transport layer is composed of a charge transport substance and, if necessary, a binder resin and an additive.

Note that the selective light-absorbing substance (dye) may be contained not only in the insulating layer but also in the photosensitive layer.

As the binder resin that can be used in the photosensitive layer of such a photoreceptor, most of the binder resins used in electrophotography can be used, and thermosetting or thermosetting resins are used.

For example, polyethylene, polypropylene, acrylic resin,
Addition polymer resins, polyaddition resins, polycondensation resins such as methacrylic resin, vinyl chloride resin, vinyl acetate resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, polycarbonate resin, silicone resin, melamine resin Copolymer resins containing two or more of the repeating units of these resins, such as vinyl chloride-vinyl acetate copolymer resins, vinyl chloride-vinyl acetate-maleic anhydride copolymer resins, etc. can. However, the binder resin is not limited to these resins, and all resins commonly used in such applications can be used.

Further, in the photoreceptor of the present invention, K in the photosensitive layer.

Organic amines can be added for the purpose of improving the carrier-generating function of the carrier-generating substance, and it is particularly preferable to add a secondary amine. Examples of such secondary amines include dimethylamine, diethylamine, di-n-propylamine, di-isopropylamine, di-n-butylamine, di-isobutylamine, di-n-amylamine,
Di-isoamylamine, di-n-hexylamine, di-
Isohexylamine, di-n-pentylamine, di-isopentylamine, di-n-octylamine, di-isooctylamine, di-n-nonylamine, di-isononylamine, di-n-decylamine, di- Examples include isodecylamine, di-n-monodecylamine, di-isomonodecylamine, di-n-dodecylamine, and di-isodobutycin. Further, the amount of the secondary amine added is 1 times or less, preferably 0.2 times to 0.00 times the amount of the carrier generating material, relative to the carrier generating material.
The number of moles is preferably in the range of 5 times.

Examples of the solvent used to form the photosensitive layer of the present invention include hydrocarbons such as hexane, benzene, toluene, and quincylene, methytoturolide, meth-tetrachloroethane, cis-1,2-dichloroethylene, 1,1. 2-)
Lichloroethane, 1°p1.1-)! Halogenated hydrocarbons such as dichlorothane, chloroform, trap rommophor, chlorobenzene, acetone, methyl ethyl ketone, ketones such as cyclohedium titanium, esters such as ethyl acetate, butyl acetate, methanol, ethanol, propatool, butanol , cyclohexanol, pectanol, ethylene glycol,
Alcohols and their derivatives such as methyl cellosolve, ethyl cellosolve, and acetic acid cellosolve. In addition to ethers such as tetrahydrofuran, 1゜4-dioxane, furan, and 7-ral, acetals, nitrogen compounds such as pyridine, amines, and amides, fatty acids and phenols, carbon billion, triethyl phosphate, etc. Any solvent such as sulfur or phosphorus compound as a sole solvent,
Alternatively, various mixed solvents containing these as main components can be mentioned.For the insulating layer, for example, all the binder resins that can be used in the photosensitive layer can be used. It requires a thickness of ~5 μm or more. Furthermore, if the insulating layer becomes thicker than 100 μm, the exposure light will be absorbed more and the sensitivity will be lowered. Therefore, the thickness of the insulating layer is preferably 2 to 100 μm, preferably 5 to 50 μm.

The insulating layer is formed, for example, by a coating method such as dip coating, spray coating, roll coating, or rotational movement coating, by a method of heat shrinking using a stretchable film, or by a method of forming a 5-ins layer by sputtering.

In addition, the film thickness must be controlled by the dielectric and process conditions of the insulating layer and photosensitive layer.

Next, the conductive support supporting the photosensitive layer may be a metal plate made of aluminum or nickel, a metal drum or metal foil, a plastic film deposited with aluminum, tin oxide, indium oxide or the like, carbon black, titanium black or the like. For example, a film or a drum made of paper, plastic, etc. coated with a conductive material such as a metal such as a tin-coated titanium oxide powder or a tin-coated fine powder can be used.

For example, the carrier-generating layer when the photosensitive layer has a laminated structure, or the photosensitive layer when it has a single-layer structure, can be formed by a carrier-generating substance alone, or by adding a suitable binder resin to it, or by further adding a specific or specific binder resin to the photosensitive layer. It can be formed by adding a substance having high mobility for carriers of non-specific polarity (ie, a carrier transporting substance).

Specifically, the formation method includes a method in which a carrier-generating substance is vacuum-deposited on the carrier transport layer, and a carrier-generating substance dissolved or dispersed in a suitable solvent alone or together with a suitable binder resin is coated and dried. Here are some ways to do it.

In this latter method, binder resins or carrier transport substances may be added, in which case
The ratio of carrier generating substance: binder resin: carrier transporting substance is 1:(0 to Zoo):(0 to 500 by weight)
), Special &C1: (0-10): (G-50) is preferable.

When the photosensitive layer is a laminated type, the carrier transport substance is 20 to 200 parts by weight per 100 parts by weight of the binder resin in the medium transport layer.
The amount is preferably 30 to 150 parts by weight. If the content of the carrier transport substance is less than this, the photosensitivity will be poor and the residual potential will tend to be high, and if it is more than this, the solvent solubility will be poor.

Further, in the photoreceptor of the present invention, the above-mentioned dye contained in the insulating layer is 0.0 parts by weight per 100 parts by weight of the binder resin.
It is desirable that the amount is 1 to 100 parts by weight, preferably 0.01 to 50 parts by weight.

Furthermore, when the photosensitive layer has a laminated structure, when used in either the charge generation layer or the charge transport layer, it is contained in an amount of 0.1 to 50% by weight, preferably 0.5 to 20% by weight, based on the layer to be added. When used as both a charge generation layer and a charge transport layer, the total content for each layer is 0.1 to 50.
It is preferably contained in an amount of 0.5 to 20% by weight. Furthermore, even when the photosensitive layer has a single layer structure, 0.
The content is preferably 1 to 50% by weight, preferably 0.5 to 20% by weight. If this content is too small, the effect of controlling color sensitivity, such as reducing the sensitivity in a specific long wavelength range, will be small, making it difficult to reproduce the desired chromatic colors, and if it is too large, the sensitivity in other wavelength ranges will also be reduced. This results in a significant decrease in overall white light sensitivity.

In the photoreceptor of the present invention, the thickness of the charge generation layer is 0.0
The thickness is preferably 1 to 10 μm, preferably 0.2 to 5 it m. If the thickness is less than G or OIAm, it tends to be difficult to uniformly form a charge generation layer, and if it exceeds 10 μm, the electrophotographic properties tend to deteriorate. The thickness of the charge transport layer is preferably 5 to 50 μm, preferably 8 to 20 μm. Even when the photosensitive layer is a single layer, the thickness of the photosensitive layer is preferably 5 to 50 μm, preferably 8 to 20 μm. If the thickness is less than 5 μm, the initial potential tends to be low, and if it exceeds 50 μm, the sensitivity tends to decrease.

In addition, as a method for manufacturing such a photoreceptor, for example, a solution containing a binder resin, a carrier transport substance, and the above-mentioned dye is coated on a conductive support via an intermediate layer or a subbing layer if necessary, and then dried and charged. Forms a transport layer. Further, for example, a carrier generating substance is dispersed in the form of fine particles of 0.01 to 5.0 μm in a dispersion medium, a binder resin and a carrier transporting substance are added if necessary, and a coating liquid is prepared by mixing and dispersing with, for example, an ultrasonic dispersion section. The photosensitive layer is then coated on the charge transport layer using a coating method such as dip, spray, blade or roll coating and dried to obtain a photosensitive layer.

The intermediate layer or subbing layer functions as an adhesive layer or a barrier layer, and in addition to the binder resin, it may contain, for example, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, vinyl chloride-vinegar [vinyl copolymer L] -Vinyl acetate-maleic anhydride copolymer, casein, starch, etc. are used.

E, Example Examples of the present invention will be described in detail below.

Example 1 On a conductive substrate 1 made of nickel, a 0.1 μm thick intermediate layer 6 made of a salt-peacetic acid be-maleic acid copolymer (S-LEC MF-10J manufactured by Sekisui Chemical Co., Ltd.) was formed.

Next, 80 parts by weight of a styryltriphenylamine compound shown in the following compound example as a carrier transport substance and 100 parts by weight of a binder resin polycarbonate (Panrai K-1300 manufactured by Kamiteijin Kasei Co., Ltd.) were dissolved in 1°2-dichlorotetraethane. , was applied onto the intermediate layer 6 to form a charge transport layer 3 having a thickness of 20 μm.

Next, 3.0 parts by weight of 4,10-dibromoanthrone purified by sublimation and ground in a ball mill for 24 hours, and binder resin polycarbonate (Panrai) L
-1250J, 1.5 parts by weight manufactured by Kijin Kasei Co., Ltd. 1,2-
A liquid obtained by dispersing 125 parts by weight of dichloroethane in a ball mill for 24 hours is spray coated on the charge transport layer 3 to form a charge generation layer 2 with a thickness of 2 μm.
A photosensitive layer 4 was formed with the charge generation layer.

Next, 1.20 parts by weight of the following structure A, 150 parts by weight of a binder resin thermosetting acrylic resin ("Dyanal HR-116J (Mitsubishi Rayon Co., Ltd. 1! 5 otj L parts, r Super Beckamine J-820" (manufactured by Nippon Reichhold)) Department, ``EPEAT 828J (manufactured by Yuka Shell Epoxy Co., Ltd.)
A solution prepared by dissolving 50 parts by weight) in 2000 parts by weight of toluene was spray coated on the charge generating layer 2, and then dried and cured at 80°C for 2 hours to form an insulating layer 5 of 20 Am. Created.

Similarly, a corresponding photoreceptor was prepared by adding an appropriate amount of dye B-F in place of the dyestuff.

(Dye person) (Dye B) (Dye D) α Maximum absorption wavelength λ of dyes λ to F (when the solvent is tetraax and lahydrofuran THF), the absorption Ad (λd) at that time, and the maximum absorption of the carrier generating substance CGMaX Table 1 shows the absorption ratio of each dye to absorption Ad (λ□8) at wavelength λ''=540 nm.

This photoreceptor was evaluated by the processes shown in FIG. 4 (1), (2), and [3].

FIG. 4 [1゛] shows a state in which the photoreceptor is negatively charged (-order charge) by DC corona discharge, and a negative charge e is generated on the insulating layer 5 between the insulating layer 5 and the photosensitive layer 4. A positive charge e is generated at the interface.

Next, when secondary charging due to alternating current corona discharge and image exposure are performed at the same time, as shown in Figure 4 [2], the unexposed portion DA will have a charge distribution as shown, and will not be exposed to light. At the portion PH, the photosensitive layer 4 becomes conductive and the charge disappears, so that the upper surface potential appears to be approximately zero.

Next, when the entire surface is exposed, as shown in Fig. 4 [3],
In the non-exposed area during image exposure, a part of the positive charge passes through the photosensitive layer 4 and neutralizes the negative charge induced at the interface with the conductive substrate 1, causing the surface potential to become negative. Become. The PH portion of the exposed area during image exposure does not change and remains approximately zero. ``In this way, an electrostatic latent image is formed on the surface of the photoreceptor due to potential contrast.

FIG. 5 is a graph chronologically showing changes in the surface potential of the photoreceptor due to the above process, and hereinafter, evaluation will be expressed by the difference ΔV between the potential of the DA area and the potential of the PH area due to full exposure.

Now, when an appropriate amount of each dye is added, the potential difference between the black paper potential and the white paper potential is Δv b = soo v.
lPitches J: :2 Duck company 1m) potential Vye node, V cyan, potential difference between V red and white paper potential Vw ΔVyellow, ΔV cyan
, ΔV red are shown in Table-2.

For comparison, if no dye is added, ΔV yel
low = 240, yellow originals are easily captured, and originals with yellow backgrounds, such as newspapers, have poor original reproducibility.

Further, ΔV cyan = 400 V, and cyan originals tend to jump, and the characters tend to tingle when, for example, thermal paper is pressed.

On the other hand, the dyes A-F of this example were added.
Vyellow decreases to a degree close to VwK, and V
cyan increased, making it possible to improve the non-reproducibility of yellow and the reproducibility of cyan.

Table-1 A 446Dm 94 0.020/0.
702 0.285B 417Dm 123
0.000 / 0.420 0.000C439
Dm 101 0.003 / 0.780
0.004D 417Dm 121 0.003
/ 0.428 0.007E 436Dm
104 0.029 / 0.642 0.0
45F 408Dm 132 0.001 /
0.415 0.002 Comparison Table-2 (Δvb=800V) Person 1.2wt% 40V 12V
656VB 1.4 #80V
480V 664VC1,0# 48
V 496V 632VD 1.6 #
64V 464V 640VE
1.1 # 32V 560V
624VFO, 9# 80V
456V 640V Now, the operation process will be explained in detail.

Each of the photoreceptors described above was assembled into a copying machine shown in FIG. 6, and an original image (color original) was copied. However, in the same figure, the layers constituting the photosensitive drum 11 (see FIG. 1(a)) are not shown.

FIG. 7 schematically shows the charge distribution state and surface potential of the photoreceptor in each step of copying, and hatching representing the cross section of each layer is omitted.

In FIG. 6, the photosensitive drum 1 rotates in the direction of arrow a.
1, first, negative charging is applied by a scorotron charger 12 to induce negative charges on the surface of the insulating layer 5 and positive charges at the interface between the insulating layer 5 and the photosensitive layer 4 (FIG. 7 [1]).

Next, while charging is performed by a Scototron secondary charger 13 having a polarity opposite to that of the charger 12 or AC, image exposure is performed using reflected light L&C from a document (not shown) through a slit on the back side. The light source for image exposure is a white halogen lamp that scans the original and provides reflected light (image exposure light) L. By this image exposure, the unexposed area (dark area) DA
Then, the negative charge on the surface of the insulating layer 5 decreases due to secondary charging, and correspondingly, a negative charge is generated at the interface between the photosensitive layer 4 and the conductive substrate 1, and the surface of the photoreceptor driver "J-11" is reduced. The potential becomes approximately zero. In the exposed area (bright area) PH, a pair of positive and negative charges is generated in the charge generation layer 2 by the image exposure light, and some of the positive charges move to the conductive substrate 1. The negative charges generated on the conductive substrate 1 side due to secondary charging are neutralized, and the remaining positive charges escape to the !iI ground circuit via the conductive substrate 1.The negative charges generated in the charge generation layer 2 are The positive charges existing at the interface between the insulating layer 5 and the photosensitive layer 4 are neutralized (FIG. 7 (2-1)).

As a result, the charges disappear and the surface potential of the photosensitive drum 11 becomes approximately zero ((2-2) in FIG. 7).

In this way, by making the charge distribution states different between the non-exposed area DA and the exposed area PH, a primary electrostatic latent image is formed. However, since the surface potential of the photosensitive drum is approximately zero in both the non-exposed area DA and the exposed area PH, it does not function as a latent image.

Next, when the entire surface is exposed with the exposure lamp 14, a pair of positive and negative charges is generated in the charge generation layer 2 in the non-exposed area DA, and the positive charges move through the photosensitive layer 4 and form the conductive substrate 1.
The negative charges neutralize part of the positive charges existing at the interface between the insulating layer 5 and the photosensitive layer 4 (see Figure 7 (3-1)).
)). As a result, the surface potential of the non-exposed portion DA of the photoreceptor drum becomes negative. In the exposed portion PH, the charge has already disappeared, so the surface potential remains approximately zero. In this way, a potential pattern (secondary electrostatic latent image) corresponding to the original is formed on the surface of the photosensitive drum 11 (FIG. 7 (3-2)).

This second electrostatic latent image is developed with positively charged toner T stored in the developing device 15 and conveyed by the developing sleeve 15a, thereby forming a toner image (FIG. 7 [4]).

The toner image fully supported on the photosensitive drum 11 is charged by a pre-transfer charger 16 and a pre-transfer exposure lamp 17. The recording paper P carrying the toner image is separated from the photoreceptor drum 11 by the separation pole 19, fixed by the fixing device 22, and discharged outside the machine as a completed copy.

The photoreceptor drum 11 on which the toner image has been transferred to the recording paper PK is connected to a static eliminating electrode 20a of a static eliminator 20 and, if necessary, a static neutralizing lamp 20.
The toner remaining on the surface without being completely transferred is removed by the cleaning blade 21a of the cleaning device 21, and the toner is prepared for the next copying.

When the color reproducibility was evaluated by image density using Fig. 6 and a copying machine, the results were as shown in Table 3.

Table-3 = Bee concentration A 1.250.00 0.00 0.91 1.1
3B 1.230,00 0.02 0.80 1.
15C1,310,000,000,781,10D
1.300.00 0.03 0.77 1.20E
1.300.00 0.01 0.81 1.10
F 1.300.00 0.00 0.70 1.1
1 comparison 1.30 0,00 0.35 0,52
It was confirmed that the yellow non-reproducibility and the cyan reproducibility were significantly improved as shown in the figure of 1.20 or higher.

Furthermore, what is noteworthy is that by adding a dye to the bulk, there is no effect on the electrophotographic properties, the repeated potential stability is stable regardless of the presence or absence of the addition, and the ultraviolet light stability is improved by adding the dye. A significant improvement was seen.

FIG. 8 shows the results of repeatedly evaluating potential stability after 20,000 copies were made using the copying machine shown in FIG. In addition, ultraviolet light irradiation (yFJ
k5 Nfu S HI, -10000V-2, manufactured by Toshiba)
When we investigated the decrease in black paper potential due to K, we found the results shown in Figure 9.

According to this, it was found that the photoreceptor according to the present invention has comparable potential stability during repeated use and is significantly superior in durability and stability against ultraviolet light, compared to a comparative example in which no dye is added. Ta.

Furthermore, since the insulating layer has abrasion resistance, it was not damaged by rubbing with a cleaning blade and exhibited good durability.

Example 2 In Example 1, the following carrier-generating substance was vacuum deposited to form a carrier-generating layer, and the following carrier-transporting substance was applied in the same manner as in Example 1 to form a carrier-transporting layer.

Carrier generating substance (thioindigo, λ company crab = 537 nm
) Carrier transport substance: Good results were obtained in this example as well, as shown in Table 4 below.

Table-4 A 1.2wt% 30V 637V
506VB 1.41+ 48V
595V 520VC1, OII
40V 608V 512VD 1.6
#40V 600V 499VE
1.8I116V 613V 512
VFO, 9# 56V 577V
508V comparison -125V 474V
536V Example 3 Example 1! A photoreceptor was prepared using the following carrier-generating substance, carrier-transporting substance, and dye GI.

Carrier generating substance (disazo type, λ: total = 630 nm)
:Carrier transport substance: Dye G: Dye H: Dye process: The physical properties of Dye G~ are shown in Table 5 below.The results are shown in Table 5 below.
6, each was good.

G 671nm 41nm 0124/0
B23 (1151H700rm 70run
04) 52 / 0f521 0Ω84I
725nm 95nm 0f) 01/04
13 04) 02 Table-6 G 1.8wt% 120V 448V
528VH1,4148V 480V
416VI 1.6132V 472V
480V comparison 10V
560V 240V Example 4 In Example 3, a photoreceptor was prepared using the following carrier-generating substance and carrier-transporting substance. The results are shown in Table 7 below.
It was as good as.

Carrier generating substance (λ: = 610 nm) Carrier transporting substance: Table 7 G 1.8wt% 128V 470V
512VH1,4# 70V 499V
467V is also I1. j-72V 480V 504
V this comparison 64V 552V
In 400V Example 3, the following carrier generating substance,
A photoreceptor was created using a carrier transport material. The results were good as shown in Table 8 below.

Carrier generating substance (λ company: =780nm) Carrier transporting substance: Table-8 H1,4# 32V 432V 3
60V1 1.6 l 24V
408V 424V Example S Salt, vinyl, vinegar, and beer male il on the conductive substrate 1 made of nickel! An intermediate layer 6 having a thickness of 0.1 μm was formed by combining (r-varnish 2MP-10J manufactured by Sekisui Chemical Co., Ltd.).

Next, the following disazo compound 1 was used as a medial transport substance.
50 parts by weight, 100 parts by weight of binder resin polycarbonate (Panrai L-1250J manufactured by Teijin Kasei), and 80 parts by weight of the charge transport material with the following structure were mixed and dispersed in 1250 parts by weight of 1,2-dichloroethane to form the intermediate layer. The photosensitive layer 4 was formed by coating on the photosensitive layer 6.

Next, in the same manner as in Example 3, an insulating layer 5 containing dye G-I was provided to produce an electrophotographic photoreceptor of the present invention having a single photosensitive layer as shown in FIG. 1(b).

(charge generating substance) (charge transport material) The results are shown in Table 9 below.

Table-9 G 1.8wt% 128V 453V
550VH1, 4-52V 470V 43
0V work 1.6 ・40V 480V
452V comparison -25V 580V 2
30V" 15L A 0.1 μm thick intermediate layer 6 made of a vinyl chloride vinegar bee maleic vinegar copolymer ("S-LEC MF-10" manufactured by Tanezu Kagaku Kogyo Co., Ltd.) is formed on a conductive substrate 1 made of aluminum. did.

Next, 4.55 parts by weight of the charge generating substance shown in Example 5,
Acrylic resin ("Elbasai") 20 as binder resin
Disperse 1.82 parts by weight of 10J DE, manufactured by Bonn Co., Ltd. in 350% of 1,2-dichloroethane, and apply 0.3 parts by weight onto the intermediate layer 6.
The second charge generation layer 22 was formed by applying the second charge generation layer 22 to a thickness of .mu.m.

Thereafter, the electrophotographic photoreceptor of the present invention as shown in FIG. 1(a2) was formed in the same manner as after the formation of the charge transport layer in Example 1.

The same evaluation was performed on the bewildering phosphor after simultaneous full-surface exposure with -order charging.

As shown in Table 10 below, good characteristics were obtained.

Table-10 (ΔVb=800V) B 1.4 # 72V 480V
665VC1,0# 49V 50G
V 641VD1.6 # 65V
452V 651VE 1.1#33V
sss$V 630VF O,9#
75V 456V 650V comparison -245
V 410V 675V On a conductive substrate 1 made of aluminum, 5 parts by weight of conductive carbon black ("Ketchin Black" manufactured by Lion Akzo) and a binder resin of chloride-vinyl-acetic-beam-maleic acid copolymer (r!-Suretsu MF-) were applied. After mixing and dispersing 2 parts by weight of 10J (manufactured by Sekisui Chemical Co., Ltd.) in methyl ethyl ketone 100317,
The above conductive support was coated to form a charge injection layer 7.

Thereafter, an electrophotographic photoreceptor of the present invention having a size 5 as shown in FIG. 1 (a3) was formed in the same manner as in Example 1 after the formation of the charge transport layer.

As a result, good characteristics were obtained as shown in Table 11 below.

Table-11 (ΔV b =800V) A 1.2wt% 45V 500V
652VB 1.4 #80V
475V 660VC1, Ol 50V
500V 63BVD 1.6#
61V 462V 641VE
1.1- 30V 570V 633V
FO, 9-72V 460V 640V
-240V 410V 685V Furthermore,
If necessary, an intermediate layer 6 may be provided between the base 1 and the charge injection layer 7, as shown by the broken line in FIG. 1(a3).

In addition, in Example 1, dye J shown in Table 12 below,
K was used.

Table-12 K 530nm 10nm O
, 625 dye J has Δλml and ABS ratio outside the range of the present invention, and that of dye J has an ABS ratio outside the range of the present invention. In addition, the following dye (dye K)
(Dye J) Both of the photoreceptors using the above dyes J and K have such poor sensitivity that the potential difference ΔV between vb and Vw is not large enough and cannot be reduced to 5oov or less. Comparative measurements were not possible. In addition, the photosensitivity is shown in Table-1 below.
It was defective like 3.

Table-13 J 250V K 530V

[Brief explanation of the drawing]

The drawings are for explaining the present invention, and include FIG.
a), (a2), (a, ) and (b) are cross-sectional views of the electrophotographic photoreceptor, Figure 2 is a graph showing the light absorption rate of each substance, and Figure 3 is the spectral sensitivity distribution of the electrophotographic photoreceptor. Figure 4 [1], [2] and [3] are schematic diagrams showing the process of electrostatic latent image formation, and Figure 5 is a graph showing the process of forming an electrostatic latent image. Graph showing changes in photoreceptor surface potential corresponding to processes; Figure 6 is a schematic front view of the interior of the copying machine; Figure 7 [1], (2-1), (2-2), [Figure 3] FIG. 8 is a graph showing the potential stability of the electrophotographic photoreceptor during repeated use, and FIG. 9 is a graph showing the ultraviolet resistance of the electrophotographic photoreceptor. In addition, in the reference numerals shown in the drawings, 1... Conductive substrate 11... Photosensitive drum 2... Charge generation layer 12...- Secondary charger 2τ...Charge generation layer 13...Secondary charger 3...Charge transport layer 14...
Full-surface exposure lamp 4...Photosensitive layer 15...
...Developer 5...Insulating layer L...
・Image exposure light 6...Intermediate layer P...
Recording paper T: Charge injection layer T: Toner. Agent: Hiroshi Aisaka, Patent Attorney Figure 3: λ (nm) Figure 5: ♂-11f4C Yogai Hikaru Kinunon Haruha (min) (Self-produced amendment document June 1, 1988 Commissioner of the Patent Office Black 1) Yu Akira 2. Name of the invention Photoreceptor 3. Relationship to the case of the person making the amendment Patent applicant address 1-26-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Name
(127) Konishiroku Photo Industry Co., Ltd. 4, Agent address: 2-4-11 Shibasaki-cho, Tachikawa-shi, Tokyo FINE Building Equipment 0425-24-541 illsu6, ? # Number of inventions increased due to positive change 7, Detailed explanation of the invention in the specification subject to amendment 8, Contents of amendment

Claims (1)

[Scope of Claims] 1. A photoreceptor having a photosensitive layer and an insulating layer as an uppermost layer, wherein at least the insulating layer of each layer contains a selective light-absorbing substance made of a dye, and A photoreceptor that satisfies the following formula. 10nm≦｜(λ^C^G^M_m_a_x−λ^d_
m_a_x)｜≦(λ^C^G^M_m_a_x−20
0 nm) 0≦Ad(λ^C^G^M_m_a_x)≦0.5 [However, λ^C^G^M_m_a_x is the maximum absorption wavelength (unit: nm) of the charge generating substance in the photosensitive layer, λ^d_m_a_x is the maximum absorption wavelength (unit: nm) of the selective light-absorbing substance, Ad(λ^C^G^M_m_a_x) is λ^C^G^
The light absorption rate of the selective light-absorbing substance at M_m_a_x, Ad(λ^d_m_a_x) is the light absorption rate of the selective light-absorbing substance at λ^d_m_a_x. ]