JPS58209751A - Photoreceptor - Google Patents

Abstract

PURPOSE:To improve initial electrostatically charged voltage and to improve the deterioration in repetitive use considerably in an electrophotographic receptor provided with a charge generation layer and a charge transfer layer on a conductive substrate by providing an N type precoating layer between the conductive substrate and the charge generation layer. CONSTITUTION:Water is added to a mixture of 10pts.wt. methylene blue and 90pts.wt. PVA (produced by Kishida Chemical) to make 10wt%, and the mixture is mixed and dispersed for 1hr with a planetary mill. The soln. is coated on an aluminum plate of 100mu and is dried, whereby a dry film of 1mu is obtd. The liquid prepd. by adding chlorinated ''Dianblue'' expressed by the constitutional formula 1 to tetrahydrofuran so as to be contained at 1wt% and grinding and mixing the same thoroughly with a ball mill is coated on said film as an N type precoating layer and is dried, whereby a charge generation layer of 1mu thickness is provided. The pyrazoline deriv. expressed by the constitutional formula 2 is compounded with polycarbonate (''Iupilon S2,000'' produced by Mitsubishi Gas Chemical) so as to be contained at 1:1 weight ratio and the mixture is prepd. into a 20wt% dichlormethane soln. Said soln. is coated thereon whereby a dry coated film of about 20mu thickness is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION In particular, the present invention relates to a method for improving the characteristics of a laminated composite photoreceptor in which a charge generation layer and an acid transfer layer are provided on a conductive support.

Conventionally, a conductive support 1- absorbs light.
A laminated composite photoreceptor is known which is provided with a charge generation layer capable of generating carriers, and further provided with a charge transfer layer capable of transporting the generated carriers.

In many cases, such laminated composite photoreceptors use organic or difficult-to-produce pigments as active ingredients in the charge generation layer, such as azo pigments, phthalocyanine pigments, perylene pigments, zinc oxide, cadmium sulfide, etc. Many pigments are known. In addition, as active ingredients in the charge transfer layer, (,'') low molecular weight ones include hecypmethylenediamine, N-(4-aminobutyl)cadaverine, iJtl.
-dodenlehydrazine + p-toluidine, 4-amino-0-xylene, N,N'-diphenyl-1,2-diaminoethane, 0~, Ill- or p-ditolylamine,
Triphenylamine, durene, 2-bromo-3.7-
Dimethylnaphthalene, 2.3.5-trimethylnaphthalene, N/-(3-70mufenyl)-N-(β-naphthyl)urea -N-(α-naphthyl)urea, 2,6-dimeglutanthracene, anthracene, 2-phenylanthracene, 9.10-dienylanthracene, 9.9-bianthranil, 2-72methylaminoanthracene, phenanthrene, 9 -Aminophenanthrene, 3,6 Dimeflufepunthrene, 5.7
-:>bromo 2-phenylindole, 2.3-diethylindoline, 3-indolylmethylamine, carbazole, 2-methylcarbazole, N-ethylcarbazole, 9-phenylcarbazole.

1.1'-dicarbazofur, 3-([·-methoxy/phenyl)oxazolidine, 3.4.5-)limethylinoxazole, 2-anilino-1,5-diphenylthiazole, 2. i, 51 minophenylimidazole,
4-Amino-3,5-methyl-■-phenylpyrazole, 2,5-bis(dimethylaminophenyl)-1,3
, 1-oxadiazole, 1.3.5-)rifenyl-4.2.4-)lyazole, 1-amino-5-phenyltetrazole, bis-diethylaminophenyl-1,3
, 6-oxadiazole 1, etc. (1,) Examples of sensitive polymers include poly-N-vinylcarbazole and its derivatives (for example, chlorine, bromine, etc. in the carbazole skeleton), rogene, and methyl groups.

(having substituents such as amino groups), polyvinylpyre/, polyvinylanthracene, pyrene-formaldehyde condensation polymers and derivatives thereof (for example, having substituents such as bromine, rogene, nitro, etc. on the pyrene skeleton)
Examples include.

Such organic laminated composite photoreceptors have been actively developed in recent years because they are light, have good loadability, are flexible, and can have various spectral sensitivity characteristics. For example, in the US time: 3°/184,237,
Charge transfer complex of poly-N-vinylcarbazole and 2,4,7-dolinitro-5)-fluorenone, JP-A-52
There is No.-551543 (・ is Japanese Patent Application Publication No. 49-10553)
In No. 6, there is a pyrazoline compound and chlordian blue (・ is a combination with squarylium, and in addition, 1 Ricoh technical report (R1 (: II (ITUe + uucal)
Report, ) I 98 f) (3)
'I] is 9-(4-diethylaminostyryl)
Anthracene or N-methyl-N-phenylhydrazono-3-methylidene-9-ethylcarbazole and bisf
It has been described that a combination with a zo compound is useful as a multifunctional photoreceptor for electrophotography.

However, from the viewpoint of Yuzu's requirements for photoreceptors for electronics and photography, the characteristics of photoreceptors are not just initial sensitivity, -it'I electric current, dark decay rate, and residual potential, but also length 1 (11 Characteristics of repeated use (5) and long-term storage (11) are important.

In particular, although the laminated type N-electronic photoreceptor has always excellent initial characteristics, it often exhibits poor repeatability and long-term use characteristics, which is a major obstacle to its practical application. Natte L・ru.

In order to correct these shortcomings, many improvements have been made in the past 1+Jr'
For example, conductive support and photoconductor 8
An adhesive layer consisting of Evogishi resin, Isonanate compound, and J (J) diene rubber is provided between the layers.
Provide a single barrier layer made of polyamide (with a - shift or a mixture of both)
(Japanese Patent Laid-Open No. 5028837), an undercoat film containing polyvinyl butyral and/or
(Japanese Patent Application Laid-Open No. 48-10044), a barrier layer containing a polymer of nitrocellulose and polyvinylpyrrolidone (Japanese Patent Application Laid-open No. 48-+20; 34). ), a single layer of burr consisting of a polymer blend or mixture of polycarbonate and polyurethane resin is provided (JP-A-4882)
These drawbacks can be solved by methods such as providing a layer containing disposable copolymerized nylon in a halogenated hydrocarbon solvent or alcohol thread solvent (Japanese Patent Application Laid-open No. 52-2563B). In order to improve the
Attempts have also been made to improve the properties of electron-accepting resin layers between the conductive support and the photoconductive layer.

(Japanese Unexamined Patent Publication No. 56-32148) The present inventors have continued their research with the aim of further improving the repeated use characteristics of a negatively charged external electrophotographic photoreceptor consisting of a charge generation layer and a charge transfer layer. Song discovered that the deterioration %1'1 of an electro-f photoreceptor could be significantly improved by providing an N-type precoat layer between the λ8 electrostatic support and the charge generation layer (the present invention). Reached.

Accordingly, the present invention provides an electron spot photoreceptor in which a layer consisting of a charge generation layer and a charge transfer layer is provided on a conductive support, in which an N-type is provided between the conductive support and the charge generation layer. There is a photoreceptor for electrophotography characterized by being provided with a precoat layer.

The present invention will be explained in detail below. FIG. 1 is a diagram for conceptually explaining the present invention. In FIG. 1, 11) is a conductive support, (2) is an N-type precoat layer, (3) is a charge generation layer,
(4) is a charge transfer layer containing an electrification-donating substance as an active ingredient.

As already mentioned, the N-type precoat layer of the photoreceptor of the present invention effectively injects the charge generated in the carrier into the conductive support when the charge generation layer is irradiated with light, and is also charged with corona. ?l/, of the glass charge at the time, and the initial 1h electric IF direction 1 at the time of the Sabato corona zone.
1-5 Sara K Ha <') M 1 flight 1111i, 't
J+deterioration/! f1. <This is an improvement.

The N-type Gucato layer used in the present invention is a precoat layer containing an N-type dye or pigment as an active ingredient, and the N-type dye or pigment is a dye or pigment that has properties as an N-type semiconductor. Examples of dyes or pigments as active ingredients of such an N-type precoat layer include those described in Japanese Patent Application Laid-Open No. 54-8 (1983).
Zn0゜1” OQ at 1750, Z '+ S
* CdS + Z rlX , C('' + □S
N-type inorganic pigments such as x or JP-A-55-16124
Various dyes such as triphenylmethane, diphenylnotane, xanthine, acridine, -azine, thiazine, thiazole, oxazine, and azo, and perinone pigments and perylene pigments having an amine group in 9 or a derivative thereof, for example, Examples include crystal violet, malachite green, rhodamine B extra, and vinacia tool.4 These N-type dyes and pigments can be dispersed as they are in a suitable organic medium with VC, coated and dried, or treated with a specific binder. Examples include polyvinyl alcohol and phenolic resin.

Evogin resin, urethane resin, etc. are dissolved in a binder and a suitable solvent, coated and dried. The thickness of this precoat layer is 0. fl 5 tl to ~5 tt, preferred (kuke 0
1μ to 1μ, and the dye or pigment content in the resin is 5 to 50% electric stitching.Already known charge generation agents are used as active ingredients in the L-O charge generation layer. For example, azo pigments such as organic monoazo, disazo, and trisazo pigments, azo lake pigments, Cu
, Mg, Pl, ZII valley tutaroaanine, halogenated copper phthalocyanine nato phthalocyanine] pigments, thioindigo series, a/[raginone series, perinone series, perylene series pigments, diA xazine series, quinacridone series, isoi7 dolino/ amorphous silicon (S+),
Selenium/(S++), furur (l1lc), cadmium sulfoselenide (Cd55e), arsenic selenoide (As2
5t・g), trAj((,-]'ntimon(S+
+□SJ), Selenide Ampmon (s+・2St・,
), (Cadmium evaporated (Cds), Cele/1 (Nicacdomium (C, IS, .), Cadmium telluride (C,
+1', ].

Acid (1111j ship (ZuO), sulfide 4+<lead (zjIS
): i,) Inorganic pigments such as mixtures or alloys of two or more of the above, acidic azo dyes such as monoazo and disazo, 0-hydroxycarboxylic acid type, peridihydroxy type, ortho-oxyazo type, etc. Acid mordant azo dyes, benzidine type, diaminodiphenylamine type, stilbene type, J acid type, continuous azo type, thiazole type.

Direct azo dyes such as urea type and cyanuric acid type, metal complex dyes such as chlorine, complex salt type, neolan type, baratin fast type, benzofast chromium type, copper complex type, basic azo dye, azoic dye, alizarin type , anthraquinone mordant dyes such as trioxyanthraquinone and polyoxyanthraquinone, anthraquinone acid dyes,
Indanthrone series, flavanthrone series, vilanthrone series, amylaminoanthraquinone series, anthrimide series, a/traginone carbanoyl series, acridone series, thiokitsunthone series, benzane]ron series, dibenzpyrenequinone series, anzanthrone series , hirazoleanthrone, hirimitoanthrone, thiazole yarn, thiophene, imidazole, phthalinocarbonic acid, many quinone and other anthralambone vat dyes, and indigoids such as indochol indigo and buoindigo. Dyes, soluble vat dyes such as anthrazole and sorendon dyes,
Carbonium dyes such as sulfur dyes, diphenylmethane series, triphenylmethane series, kidney dyes, phthalein series, and acridine threads, quinone imine dyes such as azine series, Ocano series, and thiazine series, cyanine dyes, cyanine dyes, quinoline There are various dyes such as dyes, -tro dyes, nitroso dyes, naphthoquinone dyes, sorodion dyes, and fluorescent dyes, and at least one of these dyes is used.

These charge generating agents can be dispersed in a suitable dispersion solvent, coated and dried, or coated and dried together with a binder. , condensation resin with polycarbonate,
Polystyrene, polystyrene, polyvinylcarbazole, etc. are used as a combination of vinyl materials. In some cases, the charge generation layer may be formed by vapor deposition. When coating with a binder, it is desirable to mix it so that it contains as much charge generating agent as possible. Electron-donating organic compounds or polymers are used as the components, such as (,'') low molecular weight ones such as hexyl mebrendiamine, N-(4-aminobutyl)cadaverine, 1),''-
Dodecylhydrazine, p-)luidine f4-amino 0
-xylene, N,N'-diphenyl, -1,2-diaminoethane, 0-. 111- or ■)-ditolylamine,
Triphenylamine, durene, 2-bromo-3,7-
Dimethylnaphthalene, 2,3.5-)limethylnaphthalene, N/-(3-)゛romenyln N-(β-naphthyl)urea, N'-methyl-N-(α-naphthyl)urea, N,N '--diethyl-N, (α-naphthyl)urea,
2.6-dimethylanthracene, anthracene.

2-phenylua/thracene, cy1.1 (1-dibuenylanthracene, 9.9-bianthranyl.

2-dimepluminoanthracene, phenanthrene g
7 minophenanthrene, 3.67 methylphenanthrene, 5.7-dipromo-2-phenylindole, 2,3
-dimethyl-triph, :-indolylmethylamine, Cal;C#, 2-1f-carhasol, N-carbazole, 9-phenylcarbazole, 1.1
'-Dicarpazole, 3-(', .-methogia phenyl)oxycilidine, 3.1.5-[1) Mepriso A
Gisazole, 2-anilino-1,5-diphenylpuazole, 2.4.5 trino'minophenylimidazole, 4-amino-3,5-dimethyl-1-7enylpyrazole, 2.5-bis(dimethylaminophenyl) )1.
3.1-oxydian'-ol, 1,3.5-trif-
1,-ru1.2.1-) lyazole, I-amino5
7 , :c , := Lua trasono, bissudiefno+'7'minophenyl-1,3,6-okiyajiazo, etc. (C) High molecular weight compounds include poly-N-vinylcarbazole and its derivatives (e.g. carbazole skeleton halogens such as chlorine and bromine, and substituents such as methyl groups and amine groups), polyvinylpyrene, polyvinylanthracene, bire/formaldehyde condensation polymers, and derivatives thereof.

The binder used in this charge transport layer can be the same as that used in the charge generation layer.

In addition, a plastic agent can also be added to the charge transfer layer. Further, the amount of the active ingredient used in the charge transfer layer is 5 to 80 w1. %, and the appropriate thickness is 5μ to 50μ.

The electrophotographic photoreceptor of the present invention is provided with an N-type precoat layer containing an N-type dye and a pigment as an active ingredient on a conductive substrate as described in 1-4. If you feel safe in the generation layer and the charge transfer layer, it is a laminated type N composite photoreceptor with a protective layer 4 on the L side. - The photoreceptor made in this way (5) is made of a compound with a negative 4 property or a high-density substance. , the exposed area is discharged, an electrostatic latent image is obtained, and this is developed.

In this way, the one-color light body for electric f-liu obtained by repeating l-use +1JJ
Inferiority in (IL special A <1, and especially for charging (-(direction 1)
You can get something in 1.

Characteristics of the obtained photoreceptor were evaluated using a Paper Analyzer SP-128 manufactured by Denki.

Determine the reduced exposure sensitivity (E j, /2-lux·sec) and calculate the charged baking soda after repeated corona charge exposures.5.
5KV, linear velocity 20”/n: + n, charged at V.

Immediately illuminated for 05 seconds with an illuminance of 500 Lux,
2. Repeat this operation for 25 seconds and measure the inferior IL of VcIt.
゜Example 1 Methylene tube-1 () small groin, polyvinyl/'l-
The solution was prepared to have a concentration of 10% by mass and mixed in a planetary mill for 1 hour. This solution was applied to a 100μ aluminum plate 1- and dried to obtain a 1μ dry coating film. This first layer is an N-type precoat layer, and on top of this, a solution of chlorinated Diamond Blue, which is not shown in the structural formula, added to tetrahydrofuran at a concentration of 1% by weight and pulverized for 1 minute using a Vollu mill is applied and dried. A pyrazoline derivative represented by the structural formula shown in 1 was provided with a charge generation layer of 1 μm in diameter on polycarbonate.
Dichlormeth 7J] 20% by blending with Ryogas Chemical's Yu-Piro 7S20110) to give a ratio of 1 to 1.
A dry coating film with a thickness of about 20 μm was obtained using the bath solution. For comparison, a completely similar photoreceptor was prepared except that no methylene bullion layer was provided.

The properties of these photoreceptors were as follows: 1゜Example 2 Crystal A-;
0 (11 polyurethane polyester polyol) 6
A precoat layer was obtained by applying a solution of 9 parts of Desmodur N-75 (Inonanate made of polyurethane) dissolved in 20 parts of cellosolve acetate. A 1μ film of the pigment represented by the structural formula was obtained on this soil in the same manner as in Example 1, and 33w1. A methylene chloride solution consisting of 56 wt.% triphenylamine and 56 wt.% polycarbonate was applied to a dry film thickness of 2 microns. For comparison, a pre-coat layer containing crystal byte was prepared (a photoreceptor was prepared and its properties were compared. Example 3 Zinc oxide (manufactured by Kasei Obtonics) and polyvinyl alcohol (manufactured by Kishida (manufactured by Ichigaku) i Mw 500. Saponification degree 86
, 5 nn) 1%) at a stacking ratio of 5:95, add 5) 9 parts water to 1 part 5 nn), and let it stand for 50 g (2 to 1 hour).

Thickness of this dispersion + (1 (Apply and dry on a 1μ aluminum plate so that the dry coating film becomes 1p. Deposit the chloroaluminol phthalocyanine so that the thickness becomes 4 o o x) , On top of this, M O' of pyrazoline derivative and polycarbonate used in Example 1,!ri:
A dry coating film of 20 μm was obtained.

The photoreceptor thus obtained was charged by -5.5 KV corona discharge, and the light intensity was 8001 μW/cm2.
1111 light and measure the sensitivity from the half-life time, and repeat this process (- Observe changes in charging property and sensitivity to evaluate deterioration resistance. As a comparative example, a photoreceptor without a zinc oxide thin film was used. Create and compare and evaluate in the same way.

[Brief explanation of the drawing]

Figure 1 is a schematic cross-sectional view for conceptually explaining the 1189 layer structure of the present invention. 1. Conductive support, 2. N type precoat layer, 3
...charge generation layer, 4.charge transfer layer. Applicant: Asahi Dow Co., Ltd. t1 Agent: Shi 1B @ Male Figure 1

Claims (1)

[Claims] In an electrophotographic photoreceptor in which a layer consisting of a charge generation layer and a charge transfer layer is provided on a conductive support, a 4-electric conductive support and a charge generation layer are used. (2) Photoreceptor 3 according to claim 1, wherein the active ingredient in the N-type precoat layer is an N-type dye or pigment;