DE2352112A1 - SENSITIZER FOR USE IN AN ELECTROPHOTOGRAPHIC LIGHT SENSITIVE MATERIAL - Google Patents

Description

PATENT LAWYERS

DR. E. WIEGAND DIPL-ING. W. NIEMANK DR. M. KÖHLER DIPL-ING. C. GERNHARDT

MONKS. HAMBURG 2352112

TELEPHONE: 555476 8000 MÖ N CH E N 2,

TELEGRAMS: KARPATENT MATH ILDENSTRASSE

W 41 808/73 - Ko / Ja - ^ October

Fuji Photo Film Co. Ltd., Minami Ashigara-Shi, Kanagawa (Japan)

Sensitizer for use in an electrophotographic photosensitive material

The invention relates to a sensitizer for use in an electrophotographic photosensitive Material in which an organic compound is used as a photoconductor.

According to the invention, there is provided a sensitizer for use in an electrophotographic photosensitive material which contains an organic photoconductor, the sensitizer being a pyrylium salt having a carbazole ring represented by the following general formula (D

409816/1116

(D

contains, wherein FL contains a hydrogen atom, an alkyl group with 1 to 5 carbon atoms, a haloalkyl group with 1 to 5 carbon atoms, a cyanoalkyl group with 2 to 6 carbon atoms, a hydroxyalkyl group with 1 to 5 carbon atoms or an acyl group, Rp a hydrogen atom, a halogen atom or a nitro group, FU a group

Usually a hydrogen atom or a hydroxyl group, where R ^ and Rt together can also form a substituted or unsubstituted benzene or naphthalene ring, the substituents consisting of alkyl groups with 1 to 5 carbon atoms, alkoxy groups with 1 to 3 carbon atoms , a nitro group or a halogen atom, Rj- can be a hydrogen atom or a group

a hydrogen atom, a halogen atom, an amino group, an alkylamino group having 1 to 4 carbon atoms or a

409816/1116

Alkyl group with 1 to 5 carbon atoms, X the radicals Cl "", Br "", J ~, ClO, "", KO ₇ ", HSO ^" or BF ^ "mean.

In electrophotography, where an organic photoconductor is used, the element most affecting photosensitivity is a sensitizer.

As organic photoconductors for use in electrophotography Polyvinyl hetero ring compounds, for example poly-N-vinylcarbazole, have already been polynuclear aromatic vinyl polymers, for example polyvinyl anthracene, compounds of low molecular weight with hetero rings, for example, oxazole rings, thiazole rings, and the like, and similar materials are used.

However, these materials do not provide sufficient photosensitivity, when used independently.

The invention results in a fundamentally new one Sensitizer which, if added to an organic photoconductor, not only improves photosensitivity, but also extends the range of wavelengths to which the photoconductor is sensitive. In particular, it results based on the invention, a sensitizer which contains a pyrylium salt with a carbazole nucleus.

The following references describe the preparation of pyrylium salts?

a) Proceeding of the Indian Academy of Science _? Section A, 37A , 544-550, (1953) J (Chemical Abstracts, 48, 11402 (1954),

b) Proceeding of the Indian Academy of Science, Section A, ^ 4A, 77-87 (1951); (Chemical Abstracts, 46, 11189 (1952),

c) Helvetica Chimica Acta, 29, 1-15 (1956), Verlag Helvetica Chimica Acta; (Chemical. Abs tracts, 50, 6445 (1956)).

It has been found that according to the invention the production the various advantageously used in the context of the invention Pyrylium salts by condensing (A) an o-hydroxyarylaldehyde and a carbonyl compound or (B) a molecule of an aryl aldehyde and two molecules of a carbon fiber

40 98 16/1116

bond in an inert solvent, for example substituted aromatic hydrocarbons, for example nitrobenzene, chlorobenzene and the like, can be carried out, such as reported in the above literature as a convenient method for the preparation of pyrylium salts.

That is, the various pyrylium salts can be prepared according to the above reaction (A) using a o-Hydroxyarylaldehyde according to the following general Formula (III) and a carbonyl group-containing carbazole derivative corresponding to the following general formula (II) or corresponding to the above-described reaction (B) using a carbazole derivative containing a carbonyl group of the following general formula (II) and an arylaldehyde corresponding to the following general formula (IV) produced v / earth. The reactions (A) and (B) are shown schematically below:

(A): reaction between an o-hydroxyarylaldehyde (III) and a carbonyl group-containing carbazole derivative (II)

CHO

Changed (I-A)

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wherein R ^ is a hydrogen atom, an alkyl group with 1 to 5 carbon atoms, for example a methyl, ethyl, propyl, butyl or pentyl group, a haloalkyl group with 1 to carbon atoms, for example a chloromethyl, chloroethyl, chloropropyl, di. chloropropyl, chlorobutyl, bromomethyl, bromoethyl, iodomethyl, iodoethyl, fluoromethyl, fluoroethyl and the like The like., a hydroxyalkyl group having 1 to 5 carbon atoms, for example a hydroxymethyl, hydroxyethyl, hydroxypropyl, hydroxybutyl, hydroxypentyl, 2,3-dihydroxypropyl group and the like, or an acyl group, for example an acetyl, propionyl, butyroyl -, acetoactyl, benzoyl, 2-carboxybenzoy! Group and the like, R _{2 is} a hydrogen atom, a halogen atom, for example a chlorine atom, bromine atom, iodine atom or fluorine atom, or a nitro group, R 1 and R 1 an alkyl group with 1 to 5 carbon atoms, for example a methyl, ethyl, propyl, butyl or pentyl group, an alkoxy group with 1 to 3 carbon atoms, for example a methoxy, ethoxy or propoxy group, a nitro group, a halogen atom, for example a chlorine atom , a bromine atom, an iodine atom or fluorine atom, or the radicals R taken together represent a substituted or unsubstituted benzene ring or naphthalene ring, in which the substituents from an alkyl group having 1 to 5 carbon atoms, for example a methyl, ethyl, propyl, butyl or pentyl group , an alkoxy group having 1 to 3 carbon atoms, for example a methoxy, ethoxy or propoxy group, a nitro group or a halogen atom, for example a chlorine atom, a bromine atom, an iodine atom or a fluorine atom, and HX a Lewis acid such as HCl, HBr , HJ and X "mean a Lewis acid anion such as Cl", Br ", J", BF "" and the like.

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In the above process (A), the reactants are generally used in an equimolar ratio, and the reaction is carried out in an inert solvent, for example an ester, for example ethyl acetate, propyl acetate, butyl acetate and the like, a cyclic ether, for example tetrahydrofuran and the like similar materials carried out. The suitable temperature is about -10 ⁰ C to 20 ⁰ G, preferably from 5 to 10 G ^{0 0} C with reaction times of from about 5 min'bis 10 hrs., More preferably 10 minutes to 1 hour. A Lewis acid, such as HCl, HBr and HJ are generally present during the reaction.

(B): reaction between an araldehyde (IV) and a carbazole derivative (II) containing a carbonyl group

(H)

NK
+ Lp vriq-S sura

(IV)

arug i i oh changed

wherein R ^ and R _{2 have} the same meaning as in reaction (A), R _{5 is} an hydrogen atom or a group

and Rg is a hydrogen atom, a halogen atom, for example a chlorine atom, a bromine atom, iodine atom or a fluorine atom, an alkyl group having 1 to 5 carbon atoms, for example a Methyl, ethyl, propyl, butyl or pentyl group, an alino group or an alkylamino group with 1 to 4 carbon atoms, for example an ethylamino, methylamino, propylamino, Dirnethylamino, diethylamino and the like. Mean

4098 1 6/1 116

and examples of the Lewis acid from HCl, HBr, HClO ^, HNO ,,
HpSO ,, BF-, or BF ₅ (CpHc) ₂ O and X "means a Lewis acid residue such as Cl ~, Br", J ", ClO ^ *", NO ₃ ", HSO ^" or BF ^ ".

The reaction between the arylaldehyde and the carbazole derivative containing a carbonyl group according to the above reaction scheme (B) is carried out by dissolving both reactants in an equimolar amount in a solvent, for example a substituted aromatic hydrocarbon solvent, for example nitrobenzene, chlorobenzene and the like a concentration of about 1 to about 20
% By weight, preferably 2 to 10% by weight, addition of a Lewis acid, HX, for example HCl, HBr, HClO ^, HNO ,, H ₂ SO ^ ₁ BF ₃ or
BF-z (CpH ₁ -) pO, where X "is a Lewis acid residue, such as Cl", Br ~,
ClO. ", NO,"", HSO ^" or BF ^ "means, and heating the mixture to about 50 to about 150 ^° C. for about 20 minutes to about 10 hours, more generally 0.5 to 5 hours After cooling the reaction mixture to room temperature (approx
to 25 ⁰ C) this is poured into diethyl ether to precipitate the crystals. The precipitate formed in this way is filtered off and the pyrylium salt is obtained as the end product. In the case
However, this reaction requires the 3-position
or the 6-position of the carbazole ring is substituted, for example by an acetyl group or a substituent other than a hydrogen atom.

It was found experimentally within the scope of the invention that if a hydrogen atom is in the 6-position is a triarylmethane dye under the same reaction conditions is formed.

The general formulas described above (IA)
and (IB) can be collectively expressed by the following general formula

816/1116

represent where R «, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, for example a methyl, ethyl, propyl, butyl or pentyl group, a haloalkyl group with 1 to 5 carbon atoms, for example a chloromethyl, chloroethyl, chloropropyl, dichloropropyl, Chlorobutyl, bromomethyl, bromoethyl, iodomethyl, iodetyl, fluoromethyl, fluoroethyl and the like, a cyanoalkyl group with 2 to 6 carbon atoms, for example a cyanomethyl, cyanoethyl, cyanopropyl, cyanobutyl, cyanpentyl group and the like., a hydroxyalkyl group with 1 to 5 carbon atoms, for example a hydroxymethyl, hydroxyethyl, hydroxypropyl, Hydroxybutyl, hydroxypentyl, 2,3-dihydroxypropyl and The like. Or an acyl group such as an acetyl, propionyl, butyroyl, acetoacetyl, benzoyl, 2-carboxybenzoyl group and the like, Rp is a hydrogen atom, a halogen atom, for example a chlorine atom, a bromine atom, an iodine atom or a fluorine atom, or a nitro group, R ^ a group

R ^ is a hydrogen atom or a hydroxyl group, where the R and R ^ radicals taken together also represent a substituted one

409816/11 16

or unsubstituted benzene ring or naphthalene ring, the substituents consisting of an alkyl group with 1 to 5 carbon atoms, for example a methyl, ethyl, propyl, butyl or pentyl group, an alkoxy group with 1 to 3 carbon atoms, for example a methoxy, ethoxy - or propoxy group, a nitro group or a halogen atom, for example a chlorine atom, a bromine atom, an iodine atom or a fluorine atom, R ₁ - a hydrogen atom or a group

Rg is a hydrogen atom, a halogen atom, for example a A chlorine atom, a bromine atom, an iodine atom or a fluorine atom, or an amino group or an alkylamino group with 1 to 4 carbon atoms, for example an ethylamino, methylamino, Propylamino, dimethylamino, diethylamino and the like, an alkyl group having 1 to 5 carbon atoms, for example a methyl, ethyl, propyl, butyl or pentyl group and X represents a group Cl ", Br", J ", ClO ^", NO ^ ", HSO ^" or BF ^ ".

The preferred substituents of the pyrylium salts according to the invention are a methyl group, an ethyl group or a hydrogen atom of the radical R _1, hydrogen atom, a ₂ for the remainder of R or a bromine atom, the radical R, is a group

where R ^ and Rp have the meaning given above, for R ^ a hydrogen atom, for R- and R ^ in connected form a benzene ring or a naphthalene ring, in which the substituents of the rings consist of a nitro group, a bromine atom or a methoxy group, for · R ₁ - a hydrogen atom or a group

40981671116

for Rg a methoxy group, a bromine atom, a ritro group or a dimethylamino group and for the radical X "the groups Cl", BF ^ "or ClO ^".

Specific examples of compounds represented by general formulas (II), - (III) and (IV) in the reaction schemes (A) and (B) are shown below.

General formula (II): Carbazole derivatives containing a carbonyl group
(II-1): 3-acetylcarbazole): 3-acetyl-9-methylcarbazole): 3-acetyl-9-ethylcarbazole): 3-acetyl-9-chloroethylcarbazole): 3-acetyl-9-hydroxyethylcarbazole

): 3-Acetyl-9-cyanoethylcarbazole (II-7): 3,9-diacetylcarbazole (II-8): 3-acetyl-6-bromo-9-ethylcarbazole (II-9): S-acetyl-G-chloro-g-ethylcarbazole General formula (III): o-hydroxyarylaldehydes (III-1): 2-hydroxybenzaldehyde (III-2): 2,4-dihydroxybenzaldehyde 3): 2-Hydroxy-3-methoxybenzaldehyde 4): 2-Hydroxy-3-bromobenzaldehyde

5): 2-hydroxy-5-nitrobenzaldehyde. (III-6): 2-Hydroxy-α-naphthaldehyde (III-7): 1-Hydroxy-ß-naphthaldehyde General formula (IV): Arylaldehydes (IV-1): Benzaldehyde
(IV-2): tolualdehyde
(IV-3): 4-methoxybenzaldehyde (IV-4): 2-bromo-4-methoxybenzaldehyde (IV-5): nitrobenzaldehyde (IV-6): dimethylaminobenzaldehyde

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The reaction between an o-hydroxyarylaldehyde and a a carbonyl group-containing carbazole derivative according to the above reaction scheme (A) is obtained by dissolving both Reactants in an organic solvent such as ethyl acetate, and with cooling to about 5 to 1CK !, saturation of the mixture carried out with a hydrogen halide with stirring. The reaction time is preferably about 10 minutes to about 1 hour. When the reaction mixture lasts for about 5 to about Is left to stand for 15 hours, the pyrylium salt precipitates in the form of crystals. The precipitate formed in this way is filtered off and the pyrylium salt is obtained as the end product.

(1-1)

(1-2) (1-3)

Cl

£ 09816/1116

(1-5)

(1-6)

OCH-

Cl

(1-7)

01 "

CH,

409816/1 1

(1-8)

Cl

(1-9)

H, CO

Cl "

2 ^H 5

(I-IO)

Br

Cl

(1-11)

Cl

A09816 / 1 1

(1-12)

OCH-

(1-13) Br.

(I-3A)

NO,

N '

CH.

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The preparation of the pyrylium salts according to the above The process described is explained in detail below with reference to the following production examples.

Production example 1

4.88 g of 2-hydroxybenzaldehyde (II-1) and 9.48 g of 3-acetyl-9-ethylcarbazole (II-3) are dissolved in 400 ml of ethyl acetate and then the total amount is cooled on CPC with ice.

When hydrogen chloride gas was passed through, was a dark green precipitate formed. After introducing hydrogen chloride gas for about 30 minutes, the reaction mixture was allowed to stand overnight. Subsequently, the educated The precipitate is filtered off, washed with ethyl acetate and dried. The product thus obtained was treated with chloroform extracted and the extract concentrated and obtained as the end product, the Pj-ryliumsalz. This connection had the following Structure:

The maximum absorption wavelength of this compound in chloroform was 537 m / u,

Manufacturing example 2

In the same manner as in Preparation Example 1, using 2-hydroxy-a-naphthaldehyde (IXI-6) and S-acetyl-S-ethylcarbazole (II-3) _s, a pyrylium salt represented by the following structural formula was prepared?

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Cl "

The maximum absorption wavelength of this compound in chloroform was 547 µm.

Manufacturing example 3

In the same way as in Preparation Example 1 below Use of 2-hydroxy-5-nitrobenzaldehyde (III-5) and 3-acetyl-9-ethylcarbazole (II-3) A pyrylium salt was prepared with the following structural formula:

The maximum absorption wavelength of this compound in chloroform was 574 m / u,

Production example 4

In the same ¥ eise as in Preparation Example 1 below Use of 2-hydroxy-a-naphthaldehyde (ΙΪΙ-6) and 3-acetyl-6-bromo-9-ethylcarba2ol (II-8) a pyrylium salt was prepared with the following structural formula:

18/1116

Cl "

The maximum absorption wavelength of this compound in chloroform was 542 m / u.

Production example 5

.1.4 g of 4-methoxybenzaldehyde (IV-3) and 6.3 g of 3-acetyl-6-bromo-9-ethylcarbazole (II-8) are dissolved in 50 g of nitrobenzene and after adding 100 ml of boron trifluoride ethylate for 2 hours. heated on a water bath. The obtained reaction solution was poured into a large amount of dietary ether and it became a precipitate of the compound formed is obtained. The precipitation was filtered off, washed with dietary ether and dried.

The product was further extracted with ether, and the The extract was concentrated, the pyrylium salt being obtained in the form of crystals as the end product. From its infrared spectrum the acetyl group was gone. The product should therefore have the following structural formula:

409816/1 1 16

- 18 -

OCH,

BF ₁

The maximum absorption wavelength of this compound in chloroform is 544 m / u.

Comparative manufacturing example

The same procedures as in Example 5 were followed, but using 3-acetyl-9-ethylcarbazole (II-3) instead of 3-acetyl-6-bromo-9-ethylcarbazole is used. It was found that the 6-position is occupied by a hydrogen atom and is therefore reactive, a triarylmethane dye was formed according to the following structural formula:

COCH,

OCH

TC.

COCH

0 9 8 16/1116

_ 19 -

On infrared spectral analysis, this compound showed a peak at 1665 cm, which is characteristic of the acetyl group and the maximum absorption wavelength of the compound in chloroform was .596 m / u, so that the compound was blue. This compound has a sensitizing effect to organic photoconductive materials and is used in Japanese Patent application 57400/72 corresponding to US serial no. 367 528 dated June 6, 1973.

The carbazole ring-containing pyrylium salts thus obtained showed effective sensitizing effects to various organic photoconductive materials. In particular, they were effective for organic photoconductive materials Carbazole systems as described in U.S. Patents 3,206,306, 3,240,594, 3,240,595 and 3,704,119, British Patent 964 879j Japanese Patent Publications 14 393/65 and 21 054/73, Japanese Patent Applications 74 489/70, 50 966/72 and the like. Are given.

The sensitizer according to the invention is added to the organic photoconductive material in an amount of 0.01-15 % By weight, in particular 0.01 to 10% by weight, based on the weight of the organic photoconductive material is added.

The organic photoconductive materials for use in electrophotography _3, which are sensitized with the sensitizer according to the invention, can be developed in both dry and wet manners. Specific treatments for this are given in U.S. Patents 2,221,776, 2,297,691, 2,907,674, 3,081,263, 3,241,998, and the like. For example, an organic photoconductive material ^ such as poly-N-vinylcarbazole and the pyrylium salts according to the invention in an organic solvent, for example iialogenierten hydrocarbons ₉ Z ₀ as chloroform, methylene chloride _s ethylene chloride _g dissolved and so mounted on the conductive support ^ that the dry strength is about 5 to 50 microns; to which an ironing cover is applied "

16/1116

The invention is described in detail below with reference to the "Examples", but none of them describe the invention Way intended to limit. Unless otherwise indicated, all percentages and parts are by weight.

example 1

One obtained by dissolving 25 g of poly-N-vinylcarbazole (molecular weight about 300,000) and 50 mg of the pyrylium salt obtained according to Preparation Example 1 in 200 ml of methylene chloride The resulting solution was applied to a dry thickness of about 10 microns on a paper that was subjected to an electroconductive treatment was subjected to by thereupon Calgonite Conductive Polymer 261 (trade name of Calgon Corp. for a Product presumably of the following structure

-CH.

(Cl ")

where η represents a positive number) in an amount of about 3 g / m had been drawn up, drawn up. In the manner customary for electrophotography, this was obtained photosensitive material charged in the dark, imagewise at an exposure amount of 190 Ix.sec. using a white light emitting light source exposed. In development treatment a distinct image was reproduced of the material. In addition, there was a developer who was a carrier made of glass beads coated with nitrocellulose with a particle size of 0.4 mm, which then absorbs a

L 0 9 8 1 6/1 1 1 6

Kneaded mixture of carbon black and polystyrene (5: 5 by weight) were used.

The amount of the sensitizer (compound corresponding to Preparation Example 1) added was varied and the appropriate one Exposure amount examined. The results obtained are summarized in Table I below.

Table I.

Amount of added Example 2 Exposure amount Pyrylium salt (mg) (Ix.sek) without 20,000 10 1 190 50 190 100 90 200 78 400 52

The pyrylium salt obtained in Preparation Example 2 was added to 20 g of a poly-N-vinylcarbazole (as in Example 1 indicated) and the sensitizing effect. examined in the same manner as in Example 1. The results are contained in the following Table II.

Table II Exposure amount Amount of added (Ix.sek) Pyrylium salt (mg) 20,000 without 990 1 110 5 190 10 180 20th 240 40

0 9 8 16/1116

Example 5

20 g of a poly-N-vinylcarbazole (as indicated in Example 1) and the compounds listed in Table III in the amounts indicated there were dissolved in 200 ml of methylene chloride solved. The resulting solution was deposited on a polyethylene terephthalate film with vacuum deposited aluminum (Metalumy from Toray Industries, Inc.) to a dry thickness of 15 microns raised. In the usual electrophotography Thus, the photosensitive materials thus obtained were charged in the dark to a white light-emitting one Exposed to a light source through an original image and a developing treatment using a liquid developer subjected, which by dispersing 1 g of a commercially available black offset printing ink of the following composition had been prepared in 1 1 cyclohexane.

Composition of offset black ink

soot

blue alkaline *

phenol-formaldehyde resin modified with rosin boiled linseed oil

15 parts by weight 7 parts by weight

55 parts by weight 15 parts by weight

HO -

NH

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As a result, pronounced images were obtained. The corresponding exposure amounts are given in Table III below listed.

Tabel III Exposure amount
(lx.sec) Pyryliuia salt added Amount (mg) 320
330
15th Manufacturing
example 3
Manufacturing
example 4
Manufacturing
example 5 200
200
200

In the foregoing, the invention has become more preferred by way of example Embodiments described without being limited thereto.

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Claims (10)

Claims ^) Sensitizer for use in an electrophotographic light-sensitive material which contains an organic photoconductor consisting of a pyrylium salt with a carbazole nucleus according to the following general formula (D wherein R * is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a haloalkyl group having 1 to 5 carbon atoms, a cyanoalkyl group having 2 to 6 carbon atoms, a hydroxyalkyl group having 1 to 5 carbon atoms or an acyl group, R _{2 is} a hydrogen atom, a halogen atom or a Nitro group, R, a group l _ f is a hydrogen atom or a hydroxyl group, where the Re and together also a substituted or unsub- substituted benzene or naphthalene ring, the substituents from an alkyl group with 1 to 5 carbon atoms, an alkoxy group with 1 to 3 carbon atoms, a nitro group or a halogen atom, 0 9 8 1 6/1 1 T 6 R ₁ - a hydrogen atom or a group Rg is a hydrogen atom, a halogen atom, an amino group, an alkylamino group having 1 to 4 carbon atoms or an alkyl group having 1 to 5 carbon atoms and X represents the radicals Cl ", Br ' HSO, "or BF ₇ " mean. 2. Sensitizer according to claim 1, characterized in that the radical R ^ consists of a hydrogen atom, a methyl group or an ethyl group, the remainder Rp consists of a hydrogen atom or bromine atom, the remainder R, consists of a Was.serstoffatom or R., and R- together form a benzene ring or a naphthalene ring, wherein the substituents are selected from a nitro group, a bromine atom or a Methoxy group, Rg a methoxy group, a bromine atom, a nitro group or a dimethylamino group and X "consists of a group Cl", BF ^ "or ClQ,". 3. Sensitizer according to claim 1 or 2, characterized in that the pyrylium salt consists of a the following connections exist (1-1) (1-2) Λ09816 / 1116 Cl Ci-5) OCH. A 0 9 8 1 6/1 1 1 6 Cl (1-7) Cl (1-8) Cl (1-9) H ₅ CO Cl 409816/1116 (i-io) (T-Il) (1-12) Cl OCH- 16/1116 (1-13) CH N- 4. Sensitizer according to claim 3 »characterized in that that the pyrylium salt consists of one of the following compounds (1-1) 0 9 8 16/1116 Cl (1-5) Cl 409816/1116 5. An electrophotographic photosensitive member consisting of a conductive support having a conductive support thereon An organic photoconductor layer containing a sensitizer according to Claims 1 to 4. 6. Electrophotographic photosensitive element according to claim 5 »characterized in that that the organic photoconductor consists of polyvinyl carbazole, 7. Electrophotographic photosensitive element according to claim 5 or 6, characterized in that that the sensitizer consists of one of the following compounds (1-1) (1-2) (1-3) 409816 / 1Ί 1 6 Br OCH. 40981 6/1116 (1-9) Cl (i-io) Ci-ii) Br Eq Cl O9 8 1 6/1 1 ■ 1 B OCH (1-13) H, C CH _x ³ V ClO, 409816/1116 8. Electrophotographic photosensitive member according to Claim 7, characterized in that the pyrylium salt is made from one of the following compounds consists (1-1) (1-2) (1-3) Cl 409816 / 111B (1-5) OCH. 9. Electrophotographic photosensitive member according to claim 5 to 8, characterized in, for. Eichn et that the sensitizer is present in an amount of 0.01 to 15 % by weight, based on the weight of the organic ehotoconductor. 10. Electrophotographic photosensitive element according to claim 5 to 9, characterized in that that the layer has a dry thickness of 5 to 50 Micron owns. 409816/1116