JPS59139039A - Photosensitive body for electrophotography - Google Patents

Abstract

PURPOSE:To obtain a photosensitive body for electrophotography having stable electric characteristics, improved sensitizing effect, and crystallization retarding effect of the photoconductive layer by providing a layer contg. fine particles of specified disazo pigment dispersed in an insulative resin between a conductive supporting body and an Se photoconductive layer. CONSTITUTION:An intermediate layer contg. fine particles of pigment expressed by the general formula I : [wherein A is a group expressed by the formula II or III; X is an aromatic ring such as benzene ring, heterocyclic ring such as indole ring, etc. or substituted body thereof; Ar<1> is an aromatic ring such as benzene ring, heterocyclic ring such as dibenzofuran ring, or substituted body thereof; Ar<2> is an aromatic ring such as benzene ring or substituted body thereof; R<1> is H, lower alkyl, (substituted) phenyl; R<2> is lower alkyl, COOH or an ester thereof] dispersed in a butyral resin, etc. is provided between a conductive supporting body and an Se photoconductive layer. In this way, a superior photosensitive body for electrophotography is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an I-interrupting body for electrophotography, in particular, a conductive support and a selenium thread source T# conductive layer with a divine foot of nine It is related to the harvested koji and the sensitizer used for photographic tools.

A type of electrophotography in which an intermediate layer in which inorganic or organic fine grains are dispersed in an insulating porridge adhesive is provided on a conductive support, and a selenium-based conductive layer is further provided on the intermediate layer. Photoreceptors are known.

(This kind of layer) In the electrophotographic photoreceptor, which is becoming dangerous,
The purpose of providing the intermediate layer is to improve the adhesion between the support and the photoconductive layer as well as to improve the electrical properties. Nakanoso is
Depending on the detection of particles dispersed in the binder, they are generally classified into two types: low resistance interlayers and nine isoelectric interlayers. Examples of the former include those using carbon as a dispersoid (Japanese Patent Publication No. 126339/1982) and those using metals or chalcogen compounds (Japanese Patent Publication No. 36859/1989).
An example of the latter is one using phthalonanine (Japanese Patent Publication No. 12671/1983). However, in the former intermediate layer, electrical properties such as charging characteristics and residual potential of the photoreceptor vary greatly depending on the dispersion conditions. Therefore, controlling the dispersion conditions is a challenge. On the other hand, when the latter intermediate layer is made of a dispersoid or a phthalocyanine pigment, there is a drawback that the electrical VF properties, particularly the residual potential, fluctuate during repeated use. In addition, as another intermediate layer that does not belong to the above category, one consisting of amorphous @fat alone without using a dispersoid is known (Japanese Patent Application Laid-open No. 103742/1983); The purpose of this is to suppress crystallization in the photoconductive layer provided thereon.
It is different from the intermediate layer of species.

The purpose of the present invention is to ensure that the electrical properties of the dispersed particles used in the intermediate layer are stable even under the dispersion conditions and repeated use, and that the intermediate layer has a sensitizing effect, a crystallization suppressing effect, and an improving flexibility effect due to improved adhesiveness. It is an object of the present invention to provide an electrophotographic photoreceptor that also has excellent electrophotographic properties.

That is, in the present invention, an intermediate layer made of fine particles of an organic pigment dispersed in an insulating resin is provided on a conductive support, and a photoconductive layer made of selenium, a selenium alloy, or a selenium compound is further provided thereon. In the provided electrophotographic photoreceptor, the organic pigment has the following general formula (where xciA, an aromatic ring such as a naphthalene salt, a hetero ring such as an indo-/"jii, cal, hexasol ring, or a benzofuran ring). or those are substituted products thereof, Ar" is an aromatic ring such as a benzene ring or naphthalene ring, or a substituted product thereof, R1" is hydrogen, a lower alkyl group, a phenyl group, or a substituted product thereof, R2 is a lower alkyl group, carboxyl group or its ester)] I+fg indicates that it is a disazo pigment formed by the following formula.

In the above, as the f substituent on the aromatic ring or heterocycle of X or the substituent on the phenyl group of R1, for example, no.
Examples of the substituent at O' or the substituent at the aromatic ring of Ar'' include norogen, lower alkyl/I/ group, lower alkoxy group, lower dialkylamino group, nitro group, cyano group, carboxyl group, sulfonic acid group, or You can find salt, etc.

To explain the present invention in more detail below, the electrophotographic photoreceptor of the present invention has a conductive support, a conductive support, a conductive layer, and a conductive layer. A specific disazo pigment represented by the above general formula is used as a quality.

Examples of the isoelectric support include plates made of metals such as Al and Ni, gold PA and their compounds, and stainless steel; M) synthetic paper or plastic snack film nucleated with metals such as Pb and Au; Examples include, but are not limited to, paper or cloth impregnated with conductive materials such as molecular quaternary ammonium salts, polystyrene sulfonates, and the like.

As mentioned above, the photoconductor is formed of selenium, a selenium alloy, or a selenium compound.

Typical selenium alloys or selenium compounds are 5
eTe, As2Se3, Se-Bi gold alloy S
Examples include e-8b alloy, but are of course not limited to these.
Any item that has been adopted from Kenrai as L)- can be used. In addition, the thickness of this original uniform layer j is suitably 100 .mu.m or less, preferably 10 to 70 .mu.m.

The intermediate layer is composed of an insulating resin as a dispersant and a disazo pigment represented by the above general formula as a dispersoid. Examples of the insulating resin here include:
Examples include epoxy resins, acrylic resins, polyimide resins, polyamide resins, butyral resins, and polyester resins, among which the use of polyester resins and butyral resins provides particularly good results.

Moreover, it is also possible to use two or more kinds of these resins in combination for the purpose of supplementing their unique properties.

On the other hand, specific examples of the disazo pigment include the following compounds, but of course the disazo pigment is not limited to these.

A in the general formula oc'4H-.

All of these disazo pigments are known substances, for example, %
It can be easily synthesized and obtained from the site described in Japanese Patent No. 56-86145.

The amount of the disazo pigment dispersed in the insulating resin is appropriately such that the disazo pigment occupies 1 to 50% by weight of the intermediate layer. If the proportion of the disazo pigment in the intermediate layer is less than 1% by weight, the resulting photoreceptor will have an increased residual potential. Conversely, if it exceeds 50% by weight, the adhesiveness of the intermediate layer itself will decrease. As a result, the effect of improving the flexibility of the resulting photoreceptor cannot be expected.

The thickness of such an intermediate layer is preferably 5 μm or less, and preferably about 1 to 3 μm. In addition to the above two components (insulating resin and disazo pigment), appropriate additives are added to this intermediate layer in order to improve and stabilize various properties of the intermediate layer or photoreceptor. Good too.

In order to actually produce the photoreceptor according to the present invention, an intermediate layer forming solution is prepared by dispersing the above-mentioned disazo pigment in an insulating resin solution, and this is coated onto a conductive support by a known method and dried. After forming an intermediate layer, selenium, a selenium alloy, or a selenium compound may be formed as a photoconductive layer on this intermediate layer by a conventional method such as a vapor deposition method or a sputtering method. Incidentally, examples of the bath medium used for preparing the intermediate layer forming liquid include tetrahydrofuran, dimethylformamide, methyl ethyl ketone, methyl cellosolve, benzene, toluene, and xylene.

The electrophotographic photoreceptor of the present invention thus produced can fully achieve the intended purpose.

Next, examples and comparative examples will be shown.

Example 1 Butyral, b fat (manufactured by Union Carbide, XYH
L) 4 parts by weight were dissolved in 11 parts by weight of tetrahydrofuran in a glass pot, and then 1 part by weight of disazo pigment of compound A18 and a stainless steel pole were added thereto and milled for 72 hours. 341 parts of tetrahydrofuran was added to the obtained dispersion to prepare an intermediate layer stock solution.

Next, apply this liquid to stainless steel (SUS 304).
It was coated on the membrane support to a dry thickness of about 1 μm, dried at 100°C for 1 hour to form an intermediate layer, and on top of that, selenium was deposited to form a layer with a thickness of about 60 μm. By forming a photo iQ layer made of amorphous selenium, a photoreceptor for single-child photography (product 1 of this study) was prepared.

For comparison, the addition of the disazo pigment was omitted as the intermediate layer forming liquid, and 9.9 parts of tetrahydrofuran was added to 1 part of the Zotyral pattern. &fu: Electrophotographic photoreceptor (comparative product 1
)It was created.

Subsequently, when the electrophotographic properties of the photoreceptors of these two types A and B were tested, a knot similar to I-1 was obtained.

As can be seen from Table 1, the effect of the intermediate layer in which the disazo pigment is dispersed in the photoreceptor of the present invention is obvious, and the residual
A significant effect on potential reduction is observed.

Moat -1 Note) ■ = The position of the cloth wall when the sample was subjected to 5KV corona discharge for 20 seconds six times.

D, D: 1st shift of VO/VM (Vo is 11j for 20 seconds
f d, potential at the time of decay).

E%: After wiping in the dark, irradiate the surface with light using a tungsten lamp so that the surface illuminance is 20 lux, and
. The amount of Fukimoto that is attached to the % of the heart.

■ Six potentials after R binary irradiation for 20 seconds.

Example 2 9 parts by weight of polyester (Dupont Formal Dress, Hollyester Adhesive) was mixed with 23 parts by weight of Tetonohydrofuran in a glass pot.
1 part by weight of the disazo pigment of the compound Ai 2 and the same stainless steel gel as in Example 1 were dissolved in the same solution and milled for 72 hours. Further, 63 parts by weight of tetrahydrofuran was added to the obtained dispersion to prepare an intermediate layer forming liquid. Next, this solution was applied onto the same support as in Example 1 so that the thickness after drying would be about 3 μm, and dried at 100°C for 1 hour to form an intermediate layer. An electrophotographic photoreceptor (invention product 2) was prepared by vacuum-depositing a 5e-Te alloy in an amount of 8 wt % to form a photoconductive layer made of amorphous 5e-Te with a thickness of about 60 μm. did.

For comparison, an electrophotographic photoreceptor (comparative product 2) was prepared in the same manner, except that β-copper phthalocyanine was used instead of the disazo pigment in the intermediate layer forming liquid.

Subsequently, these two types of photoreceptors were set in a commercially available electrophotographic copying machine and a repeated use test was conducted, and it was found that the initial residual potential of comparative product 2 increased by approximately 90V to 110V, whereas the non-xA In the bright product 2, no fluctuation in residual potential was observed.

Claims (1)

[Claims] 1. On a conductive support, an intermediate oil consisting of fine particles of an organic pigment dispersed in an insulating liquid layer, and on top of that an intermediate oil consisting of selenium, a selenium alloy, or a selenium compound. In the electrophotographic photoreceptor equipped with a nine-character electrophotometer, the organic pigment to be removed has the following general formula (where, salt or a substituted product thereof, Ar' is a benzene ring, Natalehete*Q or a substituted product thereof, Ar'
represents a benzene ring, an aromatic ring such as a naphthalene salt, or a substituted product thereof; R1 represents hydrogen, a lower alkyl group, a phenyl group, or a substituted product thereof; R2 represents a lower alkyl group, a carboxyl group, or an ester thereof; )] A photoreceptor for electrophotography, characterized in that it is a disazo bottle material represented by: