DE1597826C - Photoconductive layer - Google Patents

Description

The invention relates to a photoconductive layer composed of a photoconductor, a hydrophobic binder and a pyrylium, thiapyrylium or selenapyrylium dye salt and a method their manufacture.

Photoconductive layers of the most diverse types and methods of making electrophotographic images using such photoconductive ones Layers are already known and are described in numerous references, e.g. Am the . USA patents r 2 221 776, 2 277 013,

2 297 691, 2 357 809, 2 551582, 2 825 814, 2 833 648,

3,220,324, 3,220,831 and 3,220,833. To carry out such procedures, as a rule normally insulating photoconductive recording materials used based on an imagewise exposure using electromagnetic radiation able to address through the formation of a latent electrostatic charge image. To the generation A wide variety of customary, known working methods can then be used for permanent image recording can be applied.

In electrophotography, photoconductive insulating recording materials have proven to be special Proven useful, the photoconductive layers containing one in a resinous Disperse substance having photoconductive insulating compound. Electrophotographic Recording materials of this type are usually in the form of multilayer materials, for the production of which a photoconductive coating compound is applied to a layer substrate, which has previously been coated with a layer of an electrically conductive material, or it is are electrophotographic recording materials, for their production the photoconductive coating material directly onto an electrically conductive layer substrate made of metal or another suitable conductive material is applied.

It has been found that such photoconductive layers have an improved sensitivity and / or a advantageous spectral response as well as other desirable electrophotographic ones Have properties when one or more photosensitizing additives are incorporated into them. Typical suitable additives of this type are e.g. In U.S. Patents 3,250,615, 3,141,770 and

2,987,395. As a rule, such photosensitizers are added to photoconductive ones Layers therefore to a change in the awareness or sensitivity of a particular To effect photoconductor system and / or a change in its spectral response. Such additives can reduce the sensitivity of a recording material to radiation specific wavelength or, if desired, over a wide range of wavelengths. the The mechanism of this sensitization is not yet fully understood, but because of the Importance of these effects Ongoing intensive research to find further suitable ones Photosensitizers for photoconductive layers carried out.

The desired change in electrophotographic properties usually depends on the intended use of the photoconductive recording material. So z. B. when copying documents, the spectral electrophotographic response of the photoconductor be able to reproduce the entire very wide range of colors occurring. In a corresponding manner, other uses require special other properties, e.g. B. the ability of the recording material to take up a high surface potential and to ensure a low dark decay of the electrical charge. A high shoulder sensitivity and a high sensitivity in the sag area of the electrical H and D or blackening curve, a low residual potential after exposure and a resistance to exhaustion are also advantageous.

Heretofore, many photoconductive ones useful for forming photoconductive layers have been sensitized Coating compounds caused by adding certain dyes to the desired versatility of possible uses.

It was found, however, that conventional dye additions to photoconductive layers do not improve are able to bring about all the properties required in the entire field of electrophotography. So have z. B. the known, sensitized with the help of dyes photoconductive layers Disadvantage that they are not transparent, highly sensitive and reusable at the same time.

The object of the invention is to provide a sensitized photoconductive layer which can be produced in a simple and advantageous manner and which is distinguished by transparency, high sensitivity and rapid regeneration after use, which enables greatly improved multiple use.
The invention is based on the surprising finding that the stated object can be achieved in a particularly advantageous manner in that the photoconductive layer sensitized with the aid of dyes is given a heterogeneous two-phase structure. This is because it has been shown that homogeneous photoconductive layers of the same composition are not capable of achieving the object of the invention. So is z. B. from the stated USA patent

3 250 615 known, for sensitizing photoconductive layers, dyes of the same type as in to use the photoconductive layers of the invention. The known photoconductive layers are however homogeneous to the difference from the invention, which has the consequence that they the

do not show advantageous properties in terms of increased sensitivity and reusability, how z. B. from the results of Examples 2 and 3 given below.

The invention relates to a photoconductive layer composed of a photoconductor, a hydrophobic one Binder and a pyrylium, thiapyrylium or selenapyrylium dye salt, which are characterized is that they have the binder and the dye salt in the form of a discontinuous phase, which at 2500x magnification is visible in the microscope and which is dispersed in a continuous phase is, contains.

The invention also relates to a method for the production of such a photoconductive layer, in which a solution or suspension of a Photoconductor in a solution of a pyrylium, thiapyrylium or selenapyrylium dye salt and a hydrophobic binder is applied to a substrate and dried, thereby is characterized in that the dried photoconductive layer with a solvent or with the Vapor of a solvent is softened until, at 2500x magnification in the microscope, a Segregation becomes visible, and that the segregated photoconductive layer is dried.

The photoconductive layer according to the invention contains the dye and the hydrophobic binder in the form of a heterogeneous two-phase system that has an absorption maximum in a different wavelength range has as a layer not present in the form of the heterogeneous two-phase system from the same components.

It was found that many dye salts and their mixtures of the Pyrylium-, Thiapyrylium- and selenapyrylium dye salts together with hydrophobic binders to form one separately recognizable and detectable heterogeneous two-phase system can be solved. It was found that the obtained Zweiphasensystenr both as a photoconductor and as a sensitizer for containing photoconductors Recording materials is useful.

To produce the photoconductive layer according to the invention, a solution containing the required components can be applied in a conventionally known manner in the form of a layer to a suitable substrate, and the characteristic two-phase system can be produced in situ in the layer obtained. An advantageous procedure for converting a homogeneous layer of dye and binder into the heterogeneous system according to the invention is to bring the layer into contact for a long time with vapors of a solvent that is suitable to soften the layer, the dye to migrate and to Formation of aggregates is brought about in a two-phase system. In general, such a steam treatment effective for a considerable amount of the characteristic of the photoconductive layer according to the invention the composition of the dye and the binder within about 2 minutes at about 21.1 ⁰ C. In a corresponding manner the formation can be obtained by any other conventional procedure by applying a solution of the dye and the binder, in which the removal of the solvent is prevented, the specified composition can be prepared. Further suitable procedures for producing the composition characteristic of the photoconductive layer according to the invention are, for. B. Processes in which the homogeneous layer is immersed in a solvent or a layer is formed from an original solvent mixture containing a high-boiling solvent which remains in the layer during drying.
An observable heterogeneous structure in the photoconductive layer according to the invention indicates the presence of the characteristic composition. The presence of such a composition in the layer leads to the stated numerous improved properties when used as a photoconductor or as a photosensitizing additive for other photoconductors. The characteristic composition, after in situ formation in the photoconductive layer, results in a heterogeneous appearance when viewed at 2500X magnification, although it may appear optically clear when viewed with the naked eye without magnification. In other photoconductive layers according to the invention, there may be a macroscopically heterogeneous state. In a typical composition, the aggregates in the discontinuous phase are predominantly in the range of about 0.1 to 25 microns.

The compositions characteristic of the photoconductive layers according to the invention result in numerous beneficial properties in the field of electrophotography. Electrophotographic Recording materials which have photoconductive layers which have the specified Composition alone or together with other photoconductive compounds, draw z. B. by an increased photosensitivity regardless of the polarity of the photoconductive Surface charge applied to the recording material. The charge can be both positive as well as being negative. Such photoconductive recording materials have a high photosensitivity and photoconductivity as well as good regeneration. The tendency for such photoconductive Recording materials containing layers according to the invention after charging and loading

. Regenerating exposure very quickly is important for continuous or cyclic electrophotographic Applications. Such electrophotographic recording materials have an improved ability repeats a high surface potential after completion of a charge-exposure-development cycle to record. Such recording materials are therefore characterized by their resistance against electrical fatigue or exhaustion, which is normally associated with known, Photoconductor-containing recording materials is characteristic and their rapid reuse makes impossible.

The known photoconductive layers can be produced in very different ways. A typical such manufacturing method is to produce a solution containing a organic photoconductor, a hydrophobic polycarbonate binder and a pyrylium sensitizing dye according to that disclosed in the U.S. patent 3 141 770 and in the form of a layer on a suitable electrical conductive substrate by casting or

Apply coating. A photoconductive layer produced in the manner indicated absorbs Radiation in a certain wavelength range that is characteristic of the dye used, and has a practically homogeneous appearance at 2500x magnification.

The electrophotographic properties of these known photoconductive layers are conventional Charging, imagewise exposure and development capable of producing a usable image, However, the photoconductive layers of the invention make a substantial improvement numerous electrophotographic properties are achieved, particularly one by the formation of the specified Increase in sensitivity due to non-homogeneous two-phase system.

The radiation absorption maximum of the heterogeneous system according to the invention is significantly shifted from the radiation absorption maximum of the practically homogeneous untreated Dye solution containing dye and binder. Such an absorption maximum shift in the formation of the heterogeneous two-phase system is generally of the order of magnitude of at least about ΙΟπίμ. Will dye mixtures is used, a dye can shift an absorption maximum in the direction of a longer one Wavelength and another dye show an absorption maximum shift in the direction of a cause shorter wavelength. In these cases the formation of heterogeneous composition can occur more easily recognized when viewed under magnification. To produce a Layer with the indicated improved properties can be one as described above and in Example 1 exposed photoconductive layer to the vapor of an organic solvent will. Such a treatment for about 2 minutes at room temperature or around 21 ° C causes changes in the layer. So z. B. the color of the layer during treatment e.g. B. from a deep blue to a dark red, and radiation of a different wavelength range than in the original layer is absorbed. The photoconductive layer is taken out of the solvent vapor and under magnification considered, it is found that the layer containing the particular composition described has the appearance of a heterogeneous two-phase system. .

A photoconductive layer converted as described above according to the present invention has besides the change in the physical appearance has also undergone further transformations, as they have new properties, e.g. B. increased electrophotographic sensitivity, sometimes regardless the polarity of the original electrostatic charge. Sometimes there is also the dark conductivity of the layer converted in the specified manner is reduced, and the layer can be repeated can be charged and exposed without electrical fatigue being noticeable. Further step in the case of these photoconductive layers according to the invention, no "memory" or retained spurious ones Pictures on with subsequent recharge and exposure. Furthermore, the photoconductive Layers according to the invention are charged rapidly, and their charge stability is high when they are then subjected to high humidity or repeatedly exposed and developed.

Typical pyrylium, suitable for sensitizing the photoconductive layers according to the invention Thiapyrylium and selenapyrylium dye salts are those of the general formula

in which R ^a , R ^b , R ^c , R ^d and R ^e stand alone hydrogen atoms or aliphatic or aromatic groups with usually 1 to 15 carbon atoms, z. B. alkyl groups, for example methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, amyl, isoamyl, hexyl, octyl, nonyl, dodecyl, styryl, methoxystyryl, Diethoxystyryl, dimethylaminostyryl, 1 - butyl - 4 - ρ - dimethylaminophenyl -1,3 - butadienyl, β - ethyl - 4 - dimethylaminostyryl groups, alkoxy groups, e.g. B. methoxy, ethoxy, propoxy, butoxy, amyloxy, hexoxy or octoxy groups, aryl groups, e.g. B. phenyl, 4-diphenyl groups, alkylphenyl groups, for example 4-ethylphenyl or 4-propylphenyl groups, alkoxyphenyl groups, e.g. B. 4-ethoxyphenyl, 4 - methoxyphenyl, 4 - amyloxyphenyl, 2 - hexoxyphenyl, 2 - methoxyphenyl or 3,4 - dimethoxyphenyl groups, β - hydroxyalkoxyphenyl groups, e.g. B: 2 - hydroxyethoxyphenyl or 3 - hydroxyethoxyphenyl groups, 4-hydroxyphenyl or halophenyl groups, e.g. B. 2,4 - dichlorophenyl, 3,4 - dibromophenyl, 4 - chlorophenyl or 2,4 - dichlorophenyl groups, azidophenyl, nitrophenyl or aminophenyl groups, e.g. B. 4 - diethylaminophenyl or 4 - dimethylaminophenyl groups, as well as naphthyl or vinyl groups, or the residual pairs R ^a and R ^b or R ^d and R ^e together the atoms required to complete an aryl ring bonded to the pyrylium nucleus, X a sulfur, oxygen - or selenium atom and Z is an anion ,, ζ. Β. a perchlorate, fluoroborate, iodide, chloride, bromide, sulfate, sulfonate, periodate or p-toluenesulfonate anion.

Typical suitable dye salts are listed in Table I below.

Table I.

connection
No.

Name of the connection

4- (4-bis (2-chloroethyl) aminophenyl) -2,6-di-

phenylthiapyrylium perchlorate
4- (4-dimethylaminophenyl) -2,6-diphenyl-

thiapyrylium perchlorate
4- (4-dimethylaminophenyl) -2,6-diphenyl-

thiapyrylium fluoroborate
4- (4-dimethylamino-2-methylphenyl) -

2,6-diphenylpyrylium perchlorate
4- (4-bis (2-chloroethyl) aminophenyl) -

2- (4-methoxyphenyl) -6-phenylthia-

pyrylium perchlorate

309 607/216

continuation

connection

17 18 19 20 21 22 23

Name of the connection

4- (4-dimethylaminophenyl) -2,6-diphenylthiapyrylium sulfate

4- (4-dimethylaminophenyl) -2,6-diphenylthiapyrylium p-toluenesulfonate

4- (4-dimethylaminophenyl) -2,6-diphenylpyrylium-p-toluenesulfonate

2- (2,4-Dimethoxyphenyl) -4- (4-dimethylaminophenyl) benzo (b) pyryloyl perchlorate

2,6-bis (4-ethylphenyl) -4- (4-dimethylaminophenyl) thiapyrylium perchlorate

4- (4-Dimethylaminophenyl) -2- (4-methoxyphenyl) -6-phenylthiapyrylium perchlorate

4- (4-Dimethylaminophenyl) -2- (4-ethoxyphehyl) -6-phenylthiapyrylium perchlorate

4- (4-dimethylaminophenyl) -2- (4-methoxy-

phenyl) -6- (4-methylphenyl) pyrylium per-

chlorate 4- (4-diphenylaminophenyl) -2,6-diphenyl- -

thiapyrylium perchlorate 2,4,6-triphenylpyrylium perchlorate 4- (4-methoxyphenyl) -2,6-diphenylpyry-

lium perchlorate 4- (2,4-dichlorophenyl) -2,6-diphenylpyrylium-

perchlorate 4- (3,4-dichlorophenyl) -2,6-diphenylpyry-

lium perchlorate 2,6-bis (4-methoxyphenyl) -4-phenylpyry-

lium perchlorate 6- (4-methoxyphenyl) -2,4-diphenylpyry-

lium perchlorate 2- (3,4-dichlorophenyl) -4- (4-methoxy-

phenyl) -6-phenylpyrylium perchlorate 4- (4-amyloxyphenyl) -2,6-bis (4-ethyl-

phenyl) pyrylium perchlorate 4- (4-amyloxyphenyl) -2,6-bis (4-methoxy-

phenyl) pyrylium perchlorate 2,4,6-triphenylpyrylium fluoroborate 2,6-bis (4-ethylphenyl) -4- (4-methoxyphenyl) -

pyrylium perchlorate 2,6-bis (4-ethylphenyl) -4- (4-methoxyphenyl) -

pyrylium fluoroborate 6- (3,4-diethoxystyryl) -2,4-diphenylpyry-

lium perchlorate

6- (3,4-diethoxy - /? - amylstyryl) -2,4-diphenylpyrylium fluoroborate

6- (4-dimethylamino - /? - ethylstyryl) -. 2,4-diphenylpyrylium fluoroborate 6- (1 -n-Amyl-4-p-dimethylaminopheny 1-l, 3-butadienyl) -2.4-diphenylpyrylium-

fluoroborate 6- (4-dimethylaminostyryl) -2,4-diphenyl-

pyrylium Π uoroborat 6- (f / -Ethy! -,;, (/ - dimethylaminophenyl-

vinylcn) -2,4-diphenylpyrylium fluoroborate 6- (I -butyl-4-p-dimethylaminophenyl-1,3-butadienyl) -2,4-diphenylpyrylium-

lluoborate

Ver
binding
No. Name of the connection - 34 6- (4-dimethylaminostyryl) -2,4-diphenyl- pyrylium perchlorate 35 6 - [/ y ^ bis (4-dimethylaminophenyl) vinylene] - 2,4-diphenylpyrylium perchlorate 36 2,6-bis (4-dimethylaminostyryl) -4-phenyl- pyrylium perchlorate 37 6 - (/) '- methyl-4-dimethylaminostyryl) - 2,4-diphenylpyrylium fluoroborate 38 6- (1-ethyl-4-p-dimethylaminophenyl- 1,3-butadienyl-2,4-diphenylpyrylium- fluoroborate 39 6 - [/ i, / i-bis (4-dimethylaminophenyl) vinylene] - 2,4-diphenylpyrylium fluoroborate 40 6- (1 -Methy 1-4-p-dimethylaminophenyl- 1,3-butadienyl) -2,4-diphenylpyrylium- fluoroborate 41 4- (4-dimethylaminophenyl) -2,6-diphenyl- . pyrylium perchlorate 42 2,6-bis (4-ethylphenyl) -4-phenylpyrylium- perchlorate 43 2,6-bis (4-ethylphenyl) -4-methoxyphenyl- thiapyrylium fluoroborate 44 2,4,6-triphenylthiapyrylium perchlorate 45 4- (4-methoxyphenyl) -2,6-diphenylthia- pyrylium perchlorate 46 6- (4-methoxyphenyl) -2,4-diphenylthia- pyrylium perchlorate 47 2,6-bis (4-methoxyphenyl) -4-phenylthia- pyrylium perchlorate 48 4- (2,4-dichlorophenyl) -2,6-diphenylthia- pyrylium perchlorate 49 2,4,6-tri (4-methoxyphenyl) thiapyrylium- perchlorate 50 2,6-bis (4-ethylphenyl) -4-phenylthiapyry- lium perchlorate 51 4- (4-amyloxyphenyl) -2,6-bis (4-ethylphenyl) - thiapyrylium perchlorate 52 6- (4-dimethylaminostyryl) -2,4-diphenyl- thiapyrylium perchlorate 53 2,4,6-triphenylthiapyrylium fluoroborate 54 2,4,6-triphenylthiapyrylium sulfate 55 4- (4-methoxyphenyl) -2,6-diphenylthiapyry- lium fluoroborate 56 2,4,6-triphenylthiapyrylium chloride 57 2- (4-amyloxyphenyl) -4,6-diphenylthia- pyrylium fluoroborate 58 4- (4-amyloxyphenyl) -2,6-bis (4-methoxy- phenyl) thiapyrylium perchlorate 59 2,6-bis (4-ethylphenyl) -4- (4-methoxyphenyl) - thiapyrylium perchlorate 60 4-anisyl-2,6-bis (4-n-amyloxyphenyl) thia- pyrylium chloride 61 2 - [/ i, / y-bis (4-dimethylaminophenyl) vinylene] - 4,6-diphenylthiapyrylium perchlorate 62 6 - (/) '- ethyl-4-dimethylaminostyryl) -2,4-di- phenylthiapyrylium perchlorate

11th

continuation

Connection no.

70 71 72 73 74 75 76 77 78 79

82 83 84 85 86 87 88 are pyrylium dye salts of the general formula:

Name of the connection

2- (3,4-diethoxystyryl) -4,6-diphenylthia-

pyrylium perchlorate 2,4,6-trianisylthiapyrylium perchlorate 6-ethyl-2,4-diphenylpyrylium fluoroborate 2,6-bis (4-ethylphenyl) -4- (4-methoxyphenyl) -

thiapyrylium chloride 6 [/ ^ / i-bis (4-dimethylaminophenyl) vinylene] -

2,4-di- (4-ethylphenyl) pyrylium perchlorate

2,6-bis (4-amyloxyphenyl) -4- (4-methoxy-

phenyl) thiapyrylium perchlorate 6- (3,4-diethoxy- / i-ethylstyryl) -2,4-diphenyl-

pyrylium fluoroborate 6- (4-methoxy-ß-ethystyryl) -2,4-diphenyl-

pyrylium fluoroborate 2- (4-ethylphenyl) -4,6-diphenylthiapyry-

lium perchlorate 2,6-diphenyl-4- (4-methoxyphenyl) thia-

pyrylium perchlorate 2,6-diphenyl-4- (4-methoxyphenyl) thia-

pyrylium fluoroborate 2,6-bis (4-ethylphenyl) -4- (4-n-amyloxy-

phenyl) thiapyrylium perchlorate 2,6-bis (4-methoxyphenyl) -4- (4-n-amyloxy-

phenyl) thiapyrylium perchlorate 2,4,6-tri (4-methoxyphenyl) thiapyrylium

fluoroborate 2,4-diphenyl-6- (3,4-diethoxystyryl) pyry-

lium perchlorate 4- (4-dimethylaminophenyl) -2-phenyl-

benzo (b) selenapyrylium perchlorate 2- (2,4-dimethoxyphenyl) -4- (4-dimethyl-

aminophenyl) -benzo (b) selenapyrylium-

perchlorate

4- (4-dimethylaminophenyl) -2, 6-diphenylselenapyrylium perchlorate

4- (4-dimethylaminophenyl) -2- (4-ethoxy-

phenyl) -6-phenylselenapyryliumper-

chlorate 4- (4-bis (2-chloroethyl) aminophenyl) -

2,6-diphenylselenapyrylium perchlorate 4- (4-dimethylaminophenyl) -2,6-bis (4-ethyl-

phenyl) selenapyrylium perchlorate

4- (4-dimethylamino-2-methylphenyl) -2,6-diphenylselenapyrylium perchlorate

3- (4-dimethylaminophenyl) naphtho (2, l-b) -

selenapyrylium perchlorate 4- (4-dimethylaminostyryl) -2- (4-methoxy-

phenyl) benzo (b) selenapyrylium perchlorate 2,6-di- (4-diethylaminophenyl) -4-phenyl-

selenapyrylium perchlorate 4- (4-dimethylaminophenyl) -2- (4-ethoxy-

phenyl) -6-phenylthiapyryliumfluoro-

borate

wherein X and Z have the meaning given and

ίο wherein furthermore R ₁ and R ₂ denote phenyl or naphthyl groups with at least one substituent consisting of alkyl groups with 1 to 6 carbon atoms or alkoxy groups with 1 to 6 carbon atoms, and R ₃ an arylamino or alkylamino-substituted aryl group with 1 to 6 carbon atoms, inclusive halogenated alkylaminoaryl groups with 1 to 6 carbon atoms in the alkyl

. group.

The pyrylium dyes have been used to form the heterogeneous two-phase system of the photoconductive Layer according to the invention proved to be particularly advantageous.

To form the heterogeneous two-phase system present in the photoconductive layer according to the invention suitable hydrophobic binders are e.g. polydiarylalkanes, e.g. polycarbonates and polythiocarbonates, Polyvinyl ether, polyester, poly-a-olefins and phenolic resins. Typical suitable binders of this type are listed in Table II below.

Particularly useful dyes for forming the clusters in the two-phase system of electrophotographic Materials according to the invention

No. Table II Polystyrene 35 1 Hydrophobic binders Polyvinyl toluene 2 Polyvinyl anisole 3 Polychlorostyrene 4th Poly-α-methylstyrene 40 5 Polyacenaphthalene 6th Poly (vinyl isobutyl ether) 7th Poly (vinyl cinnamate) 8th Poly (vinyl benzoate) 45 9 Poly (vinyl naphthoate) 10 Polyvinyl carbazole; 11th Poly (vinylene carbonate) 12th Polyvinyl pyridine 50 13th Poly (vinyl acetal) 14th Poly (vinyl butyral) 15th Poly (ethyl methacrylate) 16 Poly (butyl methacrylate) CC 17th Styrene-butadiene copolymer 18th Styrene methyl methacrylate mixed poly, 19th merisat Styrene-ethyl acrylate copolymer 20th Styrene-acrylonitrile copolymer 60 21 Vinyl chloride-vinyl acetate copolymer 22nd Vinylidene chloride vinyl acetate mixed poly 23 merisat 4,4'-isopropylidenediphenyl-4,4'-isopro- 65 24 pylidenedicyclohexyl carbonate mixed polymer

continuation

Hydrophobic binders

25 poly [4,4'-isopropylidenebis (2,6-dibromo-

phenyl) carbonate]

26 poly [4,4'-isopropylidenebis (2,6-dichloro- 'phenyl) carbonate]

27 poly [4,4'-isopropylidenebis (2,6-dimethyl-

phenyl) carbonate]

28 4,4'-isopropylidenediphenyl-1,4-cyclo-

hexyldimethyl carbonate copolymer

29 4,4'-isopropylidenediphenyl terephthalate

Isophthalate copolymer

30 poly (3,3'-ethylenedioxyphenylthiocarbonate)

31 4,4'-isopropylidenediphenyl carbonate

Terephthalate copolymer

32 poly (4,4'-isopropylidenediphenyl carbonate)

33 poly (4,4'-isopropylidenediphenylthio-

carbonate)

34 poly (2,2-butane bis-4-phenyl carbonate)

35 4,4'-isopropylidenediphenyl carbonate

Ethylene oxide block copolymer

36 4,4'-isopropylidenediphenyl carbonate tetra

methylene oxide block copolymer

37 poly [4,4'-isopropylidenebis (2-methyl-

phenyl) carbonate]

38 4,4'-isopropylidenedipheny 1-1,4-phenylene-

carbonate copolymer

39 4,4'-isopropylidenediphenyl-1,3-phenylene-

carbonate copolymer

40 4,4'-isopropylidenediphenyl-4,4'-diphenyl-

carbonate copolymer

41 4,4'-Isopropylidenediphenyl-4,4'-Oxydi-

phenyl carbonate copolymer

42 4,4'-isopropylidenediphenyl-4,4'-carbonyl-

diphenyl carbonate copolymer

43 4,4'-isopropylidenediphenyl-4,4'-ethylene

diphenyl carbonate copolymer

44 poly [4,4'-methylenebis (2-methylphenyl) -

carbonate]

45 Poly [I, l- (p-bromophenylethane) bis (4-phe-

nyl) carbonate]

46 ^^ '- Isopropylidenediphenyl-sulfonyl-

bis (4-phenyl) carbonate] copolymer

47 poly [I ₅ I -cyclohexanebis (4-phenyl) carbonate]

48 poly (4,4'-isopropylidenediphenoxydimethyl-

silane)

49 poly [4,4'-isopropylidene-bis (2-chloro-

phenyl) carbonate]

50 poly [a, a, a ', a'-tetramethyl-p-xylylol-

bis (4-phenyl carbonate)]

51. Poly (hexafluoroisopropylidenedi-4-phenyl carbonate)

52 polyidichlorotetrafluoroisopropylidenedi-

4-phenyl carbonate)

53 poly (4,4'-isopropylidenediphenyl-4,4'-iso-. Propylidenedibenzoate)

54 poly (4,4'-isopropylidenedibenzyl-4,4'-iso-

propylidene dibenzoate)

No. Hydrophobic binders 5 55 Poly (4,4'-isopropylidene-1-naphthyl-
carbonate ^ 56 Poly [4,4'-isopropylidene-bis (phenoxy- 4-phenylsulfonate)] IO 57 Acetophenone formaldehyde resin 58 4,4'-isopropylidene-bis (phenoxyethyl) - Ethylene terephthalate copolymer 59 Phenol formaldehyde resin 60 Polyvinyl acetophenone 15th 61 Chlorinated polypropylene 62 Chlorinated polyethylene 63 Poly (2,6-dimethylphenylene oxide) 64 Poly (neopentyl-2,6-naphthalenedicarb- 20th oxylate) 65 Ethylene terephthalate isophthalate Mixed polymer 66 2,4-phenylene-1,3-phenylene succinate ² 5 Mixed polymer 67 Poly (4,4'-isopropylidenediphenylphenyl-
nhosühat ^ 68 Poly (m-phenyl carboxylate) 69 1 ^ -Cyclohexanedimethylterephthalate- 30th Isophthalate copolymer 70 Poly (tetramethylene succinate) 71 Poly (phenolphthalein carbonate) 72 Poly (4-chloro-1,3-phenylene carbonate) 35 73 Poly (2-methyl-1,3-phenylene carbonate) 74 Poly (1,1-bis-2-naphthylthiocarbonate) 75 Poly (diphenymethane-bis-4-phenyl carbonate) 76 Poly [2,2- (3-methylbutane) bis-4-phenyl- 40 carbonate] 77 Poly [2,2- (3,3-dimethylbutane) bis-4-phenyl-
carbonateH 78. Poly {1,1 - [1 - (1 -naphthyl)] bis-4-phenyl- 45 79 Poly [2,2- (4-methylpentane) bis-4-phenyl-
carbonati 80 Poly [4; 4 '- (2-norbornylidene) diphenyl- carbonate] 50 81 Poly [4,4 '- (hexahydro-4,7-methanoindane 5-ylidene) diphenyl carbonate]

The use of binders with recurring units of the has proven to be particularly advantageous proved the following formula:

wherein R ₄ and R ₅ are hydrogen atoms, alkyl groups, for. B. methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl or decyl groups, substituted alkyl groups, e.g. B. trifluoromethyl groups, aryl groups

pen, ζ. B. phenyl or naphthyl groups, substituted aryl groups with substituents from ζ. Β. Halogen atoms or alkyl groups having 1 to 5 carbon atoms, or together those to form a cyclic hydrocarbon group, e.g. B. a cycloalkane, e.g. B. the hexyl group, or a polycycloalkane, e.g. B. the norbornyl group required carbon atoms, wherein the total number of carbon atoms in the groups R ₄ and R ₅ to 19 can be, R ₆ and R ₇ hydrogen atoms, alkyl groups with 1 to 5 carbon atoms or halogen atoms, z. B. chlorine, bromine or iodine atoms, and R _{8 is} a divalent group of the formulas

O S

Γ \ C * Γ \
KJ K ^ KJ - 0 —- C-0— CH ₃ O 0
H -CH- —C — 0— Il ■
C Γ ~ \ CIl 0
Il 0
H Il
-0 — C — 0— -0- -Λ Il
—C— 0- Λ -CH ₂ - 0
H Il
\ J Jr 0-

The use of binders with recurring units of the has proven to be particularly advantageous formula

f ?

-R — C — R — O — C— O-

proven, in which R ₄ and R _{5 have} the meaning given and R is a phenylene radical or a halogen-substituted or alkyl-substituted phenylene radical.

Typical suitable binders are e.g. In U.S. Patents 3,028,365 and 3,317,466.

The use of polycarbonates containing diarylalkane groups has proven to be particularly advantageous proven, e.g. B. those made with bisphenol A, e.g. B. by ester exchange between Diphenyl carbonate and 2,2-bis-4-hydroxyphenylpropane. Typical suitable such binders are z. In U.S. Patents 2,999,750, 3,038,874, 3,038,879, 3,038,880, 3,106,544, 3,106,545 and 3 106 546 and in Australian Patent 19 575/56.

Typical liquids suitable for treating photoconductive layers to form the in Compositions of the photoconductive layers according to the invention are e.g. B. water, organic solvents, e.g. B. aromatic hydrocarbons, e.g. B. benzene and toluene, ketones, e.g. B. Acetone and ethyl methyl ketone, halogenated hydrocarbons, e.g. B. methylene chloride and ethylene chloride, Furans, e.g. B. tetrahydrofuran, alkyl and aryl alcohols, e.g. B. methyl, ethyl and benzyl alcohol, as well as mixtures of these solvents.

The photoconductive layers according to the invention, which have the heterogeneous composition, are generally present as photoconductors or as sensitizers on a conventional, known electrically conductive layer support, e.g. B. on a conductive metal foil, a layer of a dispersed in a resin semiconductor, a conductive layer containing the sodium salt of a carboxy ester lactone of maleic anhydride or a vinyl acetate polymer, as z. In U.S. Patents 3,007,901 and 3,262,806, or on a thin film of vacuum deposited nickel, aluminum, or silver, or a conductive layer of the type described in U.S. Patent 3,245,833, z. B. made of copper (I) iodide or silver iodide. The coating of the support can be carried out in a conventional manner, for. B. by applying with a doctor blade, whirling up, dipping or spraying. The conductive layer is preferably covered with a thin layer of an insulating material selected for its adhesive and electrical properties. If necessary, however, the photoconductive layer can be applied directly to the electrically conductive layer.
If the specified heterogeneous two-phase system is used as a photoconductor, advantageous results are obtained when the specified dyes are used in amounts of about 1 to about 50%, based on the weight of the coating composition. If the heterogeneous two-phase compositions are used as sensitizers for photoconductors, advantageous results are obtained when the specified dyes are used in amounts of about 0.01 to about 15%, based on the weight of the photoconductive coating material. However, the amount used can be varied within wide limits. The upper limit of the amount present in a sensitized layer is determined on a case-by-case basis, and the total amount of photoconductor present can vary widely depending on a wide variety of factors, e.g. B. the type of photoconductor, the desired electrophotographic response, the structure of the photoconductive recording material and its mechanical properties. If the specified heterogeneous compositions are used as a sensitizer to increase the sensitivity of other photoconductors, then smaller amounts can be used than when they are used as the sole photoconductor.

The layer thickness of the photoconductive layer according to the invention can be very different. In the Typically a wet coating will be in the range of about 0.025 to about 0.50 mm, preferably about 0.05 up to about 0.38 mm, used on a suitable support. The photoconductive layer is preferred on an insulating layer which is adjacent to an electrically conductive layer in electrophotographic Recording material is arranged, applied. The electrically conductive layer is

3Ο9 6θλ'216

preferably, by applying a solution of a conductive Substance, e.g. B. copper (I) iodide, prepared on a suitable substrate. The conductive layer can then before applying the photoconductive layer with an insulating layer made of a substance, such as B. cellulose nitrate are coated. A photoconductive recording material produced in this way possesses an increased ability to accept both a surface charge and a positive one as well as a negative potential and is therefore a preferred application. The specified Layer structure allows effective utilization of the two-phase systems according to the invention achievable high sensitivity with frequent positive and negative electrostatic charging. proceedings for the production of the electrically conductive and barrier layers z. B. U.S. Patent 3,245,833.

The structure of the electrophotographic having the photoconductive layers according to the invention Recording materials can be very different. So z. B. the photoconductive layers in Form of individual layers or in the form of several layers on suitable opaque or transparent, electrically conductive layer carriers.

Both inorganic and organic photoconductors can be used with the aid of the inventive Two-phase systems are sensitized. Typical suitable photoconductors are e.g. B. Arylamine compounds, for example diarylamines, e.g. B.

Table III

connection

Diphenylamine,
Dinaphthylamine,

N, N'-diphenylbenzidine, N-phenyl-1-naphthylamine,
N-phenyl-2-naphthylamine,
N, N '-diphenyl-p-phenylenediamine, 2-carboxy-5-chloro-4'-methoxydiphenylamine, p-anilinophenol and

Ν, Ν'-Di-i-naphthyl-p-phenylenediamine-4,4'-benzylidene-bis (N, N-diethyl-m-toluidine),

Name of the connection

4 ', 4 "-bis (diethylamino) -2', 2" -dimethyl-

4 ', 4 "-Diamino-4-dimethylamino-2', 2", 5 ', 5 "-tetramethyltriphenylmethane

4 ', 4 "-bis (diethylamino) -2,6-dichloro-2', 2" -dimethyltriphenylmethane

4 ', 4 "-bis (diethylamino) -2', 2" -dimethyl-

diphenylnaphthylmethane 2 ', 2 "-Dimethyl-4,4', 4" -tris (dimethyl-

amino) triphenyl methane 4 ', 4 "-bis (diethylamino) -2-dimethylamino-

2 ', 2 ", 5', 5" -tetramethyltriphenylmethane 4 ', 4 "-bis (diethylamino) -2-chloro-2', 2" -di. methyl-4-dimethylaminotriphenylmethane 4 ', 4 "-bis (diethylamino) -4-dimethyl-

amino-2,2 ', 2 "-trimethyltriphenylmethane 4', 4" -bis (dimethylamino) -2-chloro-2 ', 2 "-di

methyltriphenylmethane 4 ', 4 "-bis (dimethylamino) -2', 2 '-'-dimethyl-

4-methoxytriphenylmethane 4 ', 4 "-bis (benzylethylamino) -2', 2" -di-

methyltriphenylmethane 4 ', 4 "-bis (diethylamino) -2', 2", 5 ', 5 "-tetra-

methyltriphenylmethane 4 ', 4 "-bis (diethylamino) -2', 2" -diethoxy-

triphenylmethane

In the following United States patents., Numerous organic photoconductors and photoconductive Masses of the most varied types described, which improved in terms of sensitivity and regeneration when they are incorporated into the photoconductive layers according to the invention:

U.S. Patents

also triarylamines, both non-polymeric and polymeric triarylamines, e.g. B.

Triphenylamine, ■

Ν, Ν, Ν ', Ν'-tetraphenyl-m-phenylenediamine, Acetyl triphenylamine,

Lauroyl triphenylamine, '

Hexyltriphenylamine,

Dodecyl triphenylamine,

Hexaphenylpararosaniline,

4,4'-bis (diphenylamino) benzil and 4,4'-bis (diphenylamino) benzophenone, as well as Poly [N, 4 "- (N, N ', N'-triphenylbenzidine)], polyadipyltriphenylamine,

Polysebacyl triphenylamine,

Polydecamethylene triphenylamine, poly-N- (4-vinylphenyl) diphenylamine and Poly-N- (vinylphenyl) -H, a'-di-naphthylamine.

Polyarylalkanes have proven to be particularly advantageous photoconductors, e.g. B. amino-substituted triphenylmethane leuco bases, how they z. As described in French patent 1,383,461.

Typical suitable photoconductors are e.g. B. the compounds listed in Table III below:

3 037 861, 3 041 165, 3 066 023, 3 946, 3 072 479, 633, 3 047 095, 3 112 197, 3 133 022, 3 475, 3 144 060, 3 122 435, 3 127 266, 3 130 046, 3 432, 3 131 770, 3 139 338, 3 139 339, 3 140 730, 3 141 505, 3 148 982, - 3 155 503, 3 158 202, 3 161 060, 3 163 530, 3rd 163 531, 3 163 169 447, 3 174 854, 3 180 729, 3 180 189 203, 3 206 306, 3 240 597, 3 257 357 274,000 3 257 204, 3 265 496, 3 265 497 and 3:

The photoconductive layers according to the invention can be present in electrophotographic recording materials which are conventionally used known electrophotographic processes are suitable, e.g. B. to carry out the so-called xerographic process. In a method of this type, an electrophotographic recording material, that is kept in the dark, a uniform electrostatic surface charge given on the surface of the photoconductive layer by placing it under a corona discharge will. This charge is retained by the layer due to its dark insulation property, d. H. their low conductivity in the dark. Those on the surface of the photoelectric conductive layer formed electrostatic charge

is then selectively made from the surface of the layer by imagewise exposure using a conventional An exposure procedure such as a contact sheet production procedure or by lens projection of an image od. The like., consumed, with a latent electrostatic image in the photoelectrically conductive layer is formed. The fact that the incident on the photoelectric conductor Light energy is the electrostatic charge on the surface where the light struck in relation to the intensity of the exposure at a certain point, becomes with exposure the surface in this way forms a pattern of electrostatic charge.

The charge pattern created by exposure is then developed or onto another surface transferred and developed there, d. that is, both the charged and the uncharged sites are passed through Treatment with a medium containing particles with optical density that are electrostatically responsive, made visible. The electrically responsive development particles can be in flour-like form, z. B. in powder form or as a pigment in a resinous carrier, e.g. B. as a toner. A preferred one A method of applying such a toner to an electrostatic latent image for development of solid districts consists in using a magnetic contact arm. Method of manufacture and using a magnetic contact arm to apply a toner are disclosed in U.S. patents 2,786,439, 2,786,440, 2,786,441, 2,811,465, 2,874,063, 2,984,163, 3,040,704, 3,117,884 and Reissue USA. Patent 25,779. It can also develop the latent liquid electrostatic image are used. In liquid development, the development particles are applied to the image-bearing surface in one electrically insulating liquid carrier applied. Methods of developing this type are known and Z. In U.S. Patent 2,296,691 and Australian Patent 212,315. In dry development processes, the most common generation mode is a permanent deduction in having developing particles with a low melting point resin as one of its constituents. By heating the powdery image, the resin becomes then melted and fused in or onto the electrophotographic material. The powder is thereby made adherent to the surface of the photoelectrically conductive material In other cases, the electrostatic charge image formed on the photo-conductive layer on a second carrier, such as paper, from which the finished print after development and merging occurs. Operations of this type are known in the art and are e.g. B. U.S. Patents 2 297 691 and 2 551582 and in "RCA Review", Vol. 15 (1954), pp. 469 to 484.

The methods described above have been found to be useful where the photoelectrically conductive Layer is either cheap or consumable, as with the various procedures below Use of photoelectrically conductive zinc oxide or where the photoelectrically conductive medium quickly is reusable, like glassy selenium. The particular one used according to the invention Composition enables a large number of known organic photoelectrically to be used conductive compounds or compositions in xerographic processes where rapidly repeated Charging and development is desired. It is possible, for example, through the improved properties of the particular compositions used according to the invention closed loop or tape of a reusable organic photoelectrically conductive Use film in a xerographic process, with extremely fast reproduction or production of original images is possible. In addition, the photoconductive compositions naturally also with the constituents used according to the invention are in the form of a plate or drum, including coated plates or drums. With the photoconductive layer according to the invention it is possible to make copies from a microfilm or to produce an original as quickly as the mechanical working method used in each case permitted.

The following examples are intended to illustrate the invention in more detail.

example 1

Coatings are produced by adding 6 g of polycarbonate resin, produced by the reaction of phosgene with a dihydroxydiarylalkane or by ester exchange between diphenyl carbonate and 2,2 - to - 4 - hydroxyphenylpropane ("Lexan 105" - polycarbonate resin from General Electric Company), 4 g 4,4 '- benzylidine - bis (N, N - diethyl - m - toluidine) as a photoelectric conductor and 0.2 g (4-bis- (2 - chloroethyl) aminophenyi) - 2,6 - diphenylthiapyrylium perchlorate as a sensitizer in a solvent mixture of 85 g dichloromethane and 5 g methanol while stirring the solids in the solvent for 2 hours at about 21.11 ° C. The resulting solution is applied by hand by wet coating on two separate fabrics from a polyethylene terephthalate film backing which is covered with a conductive layer containing the sodium salt of a carboxy ester lactone of maleic anhydride and vinyl acetate polymer, as described in U.S. Patent 3,007,901, in applied to a thickness of 0.1016 mm. The Uberzugsklischee is maintained at 21.11 ⁰ C during coating. Both coatings are allowed to dry and only one is applied to a glass plate in the form of a strip. This plate is then turned upside down, held immediately over a bath of dichloromethane, the coating being exposed to the vapors of the bath and held therein in the light at 21.11 ° C for about 2 minutes. During this steam treatment there is a noticeable change in the color and general physical appearance of the coating. The steamed coating and the coating that has not been steamed are examined microscopically at 500X magnification. The steamed coating has assumed a heterogeneous appearance that is not present in the non-steamed coating. A spectrophotometric transfer curve of the steamed coating indicates that "the coating has 75% of the incident radiation at a

main absorption peak of 515 m μ absorbed. The non-steamed coating absorbed 89% with an absorption peak of 555 mjx. It was found that the absorption peak of the steam-treated coating in the direction of shorter wavelengths was shifted by 40 ταμ from a peak at 555 πΐμ, which is characteristic of the non-steam-treated coating. The true positive electrical sensitivity of the modified (steamed) and unmodified (non-steamed) coatings were determined in the following manner: The electrophotographic material was electrostatically charged under a corona charge source until the surface potential, as measured by an electricity meter, reached approximately 600 volts. The charged electrophotographic material was then exposed to a 3000 ° K tungsten light source through a transparent continuous neutral density or gray level wedge. The exposure caused the surface potential of the electrophotographic material below the neutral density to be reduced from its original potential, Vo, to a lower potential, V, the exact value of which depends on the amount of exposure at the point in lux x second. The results of these measurements are then plotted in a graph of the surface potential V versus the logarithm of the exposure for each event. The actual positive sensitivity of the electrophotographic material can then be expressed in terms of the reciprocal of the exposure required to reduce the surface potential to an assumed value. Unless otherwise stated, the positive sensitivity, expressed in numbers, is 10 ⁴ , divided by the exposure, in lux χ seconds, which is required to reduce the surface potential from 600 volts to a value of 100 volts. When measured as described above, the steamed coating was found to have a sensitivity of 240 when initially positively charged. The non-steamed coating has a sensitivity of 63 when initially positively charged and 35 when initially negatively charged. The sensitivities and spectral characteristics of the above-described coatings and similar coatings containing dyes other than 4 - (4 - bis (2 - chloroethyl) aminophenyl) - 2,6 - diphenylthiapyrylium perchlorate are listed in Table IV. All converted or heterogeneous coatings can be toned to produce visible images after loading and imagewise exposure. Typical suitable toners are described in Reissue USA. Patent 25,779.

Table IV

A _x Un treated coating sensitivity Modified, heterogeneous coating absorption Sensation dye (Πΐμ) absorption + 63 '■ max % opportunity 555. % -35 (Γΐμ) 75 + 240 4- (4-bis (2-chloroethyl) -amino- 89 515. -160 phenyl) -2,6-diphenylthiapyry- lium perchlorate (compound + 25 No. 1, Table I) 585 -25 86 + 1800 4- (4-dimethylaminophenyl) - 85 690 -715 2,6-diphenylthiapyrylium fluoroborate (compound no. 3, + 40 -. Table I) 538 -for 42 + 13 4- (4-dimethylamino-2-methyl- 50 Measurement too 452 -65 phenyl) -2,6-diphenylpyrylium- insensitive perchlorate (compound no. 4, + 18 Table I) 570 -13 82 +450 4- (4-dimethylaminophenyl) - 71 680 -1700 2,6-diphenylthiapyrylium p-toluenesulfonate (compound + 35 No. 7, Table I) 565 -32 65 + 800 4- (4-dimethylaminophenyl) - 67 675 -800 2- (4-methoxyphenyl) -6-phenyl- thiapyrylium perchlorate (ver + 63 binding no.11, table I) 570 -63 63 + 200 4- (4-dimethylaminophenyl) - 71 660 -320 2- (4-ethoxyphenyl) -6-phenyl- thiapyrylium perchlorate (ver + 40 binding no.12, table I) 580 -30 75 + 1800 4- (4-dimethylaminophenyl) - 75 685 -2500 2,6-diphenylthiapyrylium per- chlorate (compound no. 2, Table I)

ι ο y / ο δ ο

B e i s ρ i e 1 2

The operation of this example for the production of photoelectrically conductive coatings is broad and all the same as that described in Example 1 with the following changes: The sensitizer 4 - (4 - bis (2 - chloroethyl) aminopheny 1) - 2,6 - dipheny 1-thiapyrylium perchlorate was replaced by the same amount of 4 - (4 - dimethylaminophenyl) - 2,6 - diphenylthiapyrylium perchlorate (Compound No. 2 of Table I) replaced. Two solutions were made, one in 90 g of dichloromethane as solvent and the other in a solvent mixture of 85 g of dichloromethane and 5 g of methanol. Both solutions are stirred and, as in the example. 1 described, applied. After drying, the coating produced with dichloromethane as the only solvent is used by treating with vapors of dichloromethane as described in Example 1 into one converted into heterogeneous two-phase system. The coating from the solvent mixture of 85 g Dichloromethane and 5 g of methanol were not treated. Except for the changes described above in terms of sensitivity and spectral response, another sample becomes the first converted coating on an electrophotographic material with a conductive nickel layer applied and repeatedly charged to a potential of 600 volts and discharged by exposure, to determine the resistance of the coating to electrical fatigue or exhaustion. After 1000 such cycles with a time interval of 3 seconds between light discharge and recharge the coating assumes a potential of 550 volts under the same charging conditions on. The untreated coating only picks up a potential of 400 to 450 volts in the same system. at further implementation of the cycles described results in only a slight change in the ability of the converted coating to absorb a high surface potential, while the untreated coating continues to deteriorate in this regard. The sensitivities and spectral characteristics of the substances prepared in the manner indicated above, each being the same mixture possessed of binder and sensitizer, with only different organic in the various samples Photoelectric conductors are used are listed in Table V. '

Table V

Untreated coating (mn) absorption
% Sensation
opportunity Converted heterogeneous coating absorption
% Sensation
opportunity dye 580 75 + 40
-30 '■ ma.
(ΓΠμ) 75 + 1800
-2500 4,4'-benzylidene-bis (N, N-diethyl-
m-toluids) 595 93 + 13
-11 685 81 + 630
-400 1,3,5-triphenyl-2-pyrazoline 570 86 + 3
-5 680 79 + 360
-250 Triphenylamine 685

Example 3

There were photoelectrically conductive compositions and corresponding electrophotographic materials as described in Example 1, prepared, The following changes were made: The sensitizer 4 - (4 - bis (2 - chloroethyl) aminophenyl) - 2,6 - Diphenylthiapyryliumperchlorat was in each case by the same amount of a mixture of sensitizer dyes replaced. The sensitivities and spectral characteristics of the sensitizer mixtures containing compositions are listed in Table VI.

Table VI traded Ub
absorption
% eriug
Sensation
opportunity Robe
(ηΐμ) parent, heterogeneous
absorption
% ner coating
Sensation
opportunity Dye mixture Unb
ληιαχ
(Πΐμ) - 88 + 35
-20 565 81 + 1600
-1600 87.5 percent by weight
Compound No. 1, Table I.
12.5 percent by weight
Compound No. 2, Table I. ■ 565 82 + 32 '
-20 510 ' 65 + 1400
-1600 85 percent by weight
Compound No. 1, Table I.
15 percent by weight
Compound No. 12, Table I. 560 85 + 45
-28 560 61 + 285
-250 90 percent by weight
Compound No. 1, Table I.
10 percent by weight
Compound No. 7, Table I. 560

309 607/216

1597 25

Example 4

The procedure for this example is generally the same as that described in Example 1 for the preparation of photoelectrically conductive compositions and corresponding electrophotographic Materials with the following changes listed in Table VII

8th

26th

The sensitizer 4- (4-bis (2-chloroethyl) aminophenyl) ₇ 2,6 - diphenylthiapyrylium perchlorate was replaced by 4 - (4 - dimethylaminophenyl) -2,6 - diphenylthiapyrylium perchlorate. The sensitivities and spectral characteristics for compositions with various polymers are listed in Table VII.

Table VII dye Untreated coating '■ max
(πΐμ) absorption
% Sensation
opportunity Converted heterogeneous coating absorption
% Sensation
opportunity Poly [4,4'-isopropylidene-bis (benzyl-
alcohol) -4,4'-isopropylidene dibenzoate] 585 89 + 20
-16 '·;"« *
(ma) 85 + 1000
-1200 (Heterogeneous, by steam treatment
formed over tetrahydrofuran
Layer) 680 Poly (4,4'-isopropylidenediphenyl-
4,4'-isopropylidenedibenzoate) 580 87 + 50
-32 89 + 900
-500 675

B e i s ρ i e 1 5

An electrophotographic material was prepared by adding 9.5 g of the arylalkane polycarbonate described in Example 1 and 0.5 g of 4 - (4 - dimethylaminophenyl) - 2,6 - diphenylthiapyrylium fluoroborate as a sensitizing dye in 70 g of chloromethane as a solvent with stirring solids in the solvent during 2 hours at about 21.11 ⁰ C dissolved. A second solution was made by dissolving 9.5 g of the polycarbonate and 0.5 g of 4 - (4 - dimethylaminophenyl) - 2,6 - diphenylthiapyrylium fluoroborate in a solvent mixture consisting of 66.5 g of dichloromethane and 3.5 g of methanol Stir the solids in the solvent for 2 hours at 21.11 ^? C manufactured. The first and second solutions were then applied separately by hand using the wet lay-up technique to a masking tape or insulator-coated conductive layer of cuprous iodide on a polyethylene terephthalate film backing. (Conductive layers with or without a coating of an insulating layer of the type used in accordance with the invention are described in U.S. Pat. No. 3,245,833.) The coating plate is kept at 32.22 ° C. while layers made from the solutions described were applied. After drying, the first layer is treated with solvent vapor as described in Example 1, and then the two layers were examined microscopically at 500x magnification. The layer from the first solution was found to have a heterogeneous appearance that was not present in the second layer. The spectrophotometric transfer curve of the first layer indicated that the layer absorbs 93% of the incident radiation with an absorption peak of 640 mμ. The second coating absorbs 94% with a peak of 580 ΐημ. It was found that the absorption peak of the first coating in the direction of longer wavelengths around 60 mp. was shifted from 580 πΐμ, the absorption peak of the second coating. The sensitivities of these coatings were measured using the procedure described in Example 1. In this case, however, the sensitivity of the coating was measured on the basis of the reciprocal value of the exposure required to decrease the potential of the surface charge by 100 volts as measured by an electricity meter. The first coating was found to have a sensitivity of 630 when initially positively charged and 1200 when initially negatively charged. The second coating has a low sensitivity when it is initially positively or negatively charged. The sensitivities and spectral characteristics of the coatings prepared as described and of coatings containing dyes other than 4- (4-dimethylaminophenyl) -2,6-diphenylthiapyrylium fluoroborate are shown in Table VIII.

Table VIII

dye

Converted heterogeneous coating

absorption
%

sensitivity

Compound No. 2 of Table I.

Compound No. 1 of Table I.

Compound No. 12 of Table I.

Example 6

The procedure described in Example 1 was essentially repeated, using 685 as the sensitizer
520
640

82

92

+ 1100 and -UOO

. + 285 and -715

+ 565 and -400

0.4 g of 4 - (4 - dimethylaminophenyl) - 2,6 - diphenylthiapyrylium perchlorate instead of 4 - [4 - bis (2 - chloroethyl) aminophenyl] - 2,6 - diphenylthia-

pyrylium perchlorate were used. The polycarbonate resin, the photoelectric conductor and the sensitizer were dissolved in a mixed solvent of 52.5 g of dichloromethane and 52.5 g of 1,2-dichloroethane while stirring the solids in the solvent 5 for 2 hours at about 21.11 ° ^C. The resulting solution was then applied as a coating to a conductive substrate and converted into a two-phase system in the manner described in Example 1. The base consists of a film base made of a terpolymer of 2 percent by weight itaconic acid, 13 percent by weight methyl acrylate and 85 percent by weight vinylidene chloride, to which an evaporated nickel film has been applied. The net density of the evaporated nickel film is about 0.10 and the resistance of the backing is about 103 ohms / square (measured as described in U.S. Patent 3,245,833). This photoelectrically conductive coating has an absorption peak at 675 mμ and absorbs 94% of the incident radiation. The regeneration of the coating with a positive and negative charge and 1000 cycles within 3 seconds each is excellent, and the sensitivity, measured as described in Example 1, was 3200 with a positive charge and _i 3500 with a negative charge. The photographic density and the resistance other conductive metal substrates and the sensitivity and absorption of other organic photoelectrically conductive coatings applied directly to these metal substrates are listed in Table IX. The photoelectrically conductive layers have excellent properties with regard to regeneration and can be repeatedly charged, exposed and toned.

Table IX

nickel Leading carrier Contrary composition Organic photoelectrically conductive layer Absorp sensitivity metal was standing tion (100 V on the lower part density Ω / Fl.-E. *) '■ max % the blackening curve) (Net) 10 ³ Polycarbonate resin (mii) 95 +4000 -4000 0.10 ("Lexan-105") / 620 4,4'-benzylidine bis (N, N-diethyl- m-toluidine) (60/40) + 4% 4- (4-dimethyl- Chrome nickel aminophenyl) -2,6-di- phenylthiapyrylium fluoroborate 10 ⁶ Polycarbonate resin 90 + 2500 -2500 0.05 ("Lexan-105") /. 685 4,4'-benzylidene bis (N, N-diethyl- m-toluidine) (60/40) + 2% 4- (4-dimethyl- titanium aminophenyl) -2,6-di- phenylthiapyrylium per- chlorate 10 ⁶ Polycarbonate resin 90 + 2500 -2000. 0.05 ("Lexan-105") / 685. 4,4'-benzylidene bis (N, N-diethyl- m-toluidine) (60/40) + 2% 4- (4-dimethyl- Stainless steel· aminophenyl) -2,6-di- Type 316) phenylthiapyrylium per- chlorate 10 ⁵ Polycarbonate resin 90 + 2500 -1900 0.05 ("Lexan-105") / 685 4,4'-benzylidene bis (N, N-diethyl- m-toluidine) (60/40) + 2% 4- (4-dimethyl- aminophenyl) -2,6-di- phenylthiapyrylium per- chlorate

*) Area unit, measured as described in US Pat. No. 3,245,833.

Example 7

The procedure described in Example 1 was repeated, the dye being 2,6-bis (4-ethylphenyl) -4 - (4 - dimethylaminophenyl) thiapyrylium perchlorate (compound no. 10 in Table 1) was used. After the resulting solution had been applied as a layer by hand, the

Solvent steam treatment coated this layer with toluene. After drying it became the special one Composition formed according to the invention. The absorption maximum of the unconverted Coating was 570 πίμ and the absorption 87%, while the absorption maximum of the converted Coating 635 πΐμ and its absorption 93% fraud. The sensitivity of the coatings to both positive and negative charging was determined definitely. The sensitivity of the unconverted coating is +100 with a positive charge and with negative charge - 56, whereas the converted coating has a sensitivity of +450 with positive charge and -500 with negative charge.

Example 8

The procedure described in Example 1 was carried out using 4- (4-dimethylaminophenyl) -2.6 - Repeated diphenylthiapyrylium perchlorate as a dye and 90 g of dichloromethane as a solvent. It were then two coatings, as described in Example 1, but without the subsequent steam treatment, educated. The first coat was immediately applied by such a wiping with a solvent after the layer formation converted that the amount of solvent evaporation is low is held. The second coating is converted by briefly immersing it in a benzene bath. To After drying, the modified coatings were compared with the non-modified coating. the unmodified coating had a sensitivity! ^ from +40 or -30, whereas the first converted Coating has a sensitivity of +2000 and -2000 respectively and the second converted coating had a sensitivity of +1600 and -1800, respectively.

B e i s ρ i e 1 9

The procedure described in Example 1 was carried out using a solvent mixture with a content of a high-boiling solvent is repeated. The solvent mixture consists of 81g Dichloromethane and 9 g of toluene. From the resulting mixture, as described in Example 1, a Layer made, which is then allowed to dry. The finished modified coating has a Sensitivity with a positive charge of 1800 and with a negative charge of 2100.

Claims (1)

Patent claims: 1. Photoconductive layer made of a photoconductor, a hydrophobic binder and a pyrylium ^ thiapyrylium or selenapyrylium dye salt, characterized in that it contains the binder and the dye salt in the form a discontinuous phase which is visible at 2500x magnification in the microscope and which is dispersed in a continuous phase contains. 2. Photoconductive layer according to claim 1, characterized in that it is a pyrylium, Thiapyrylium or selenapyrylium dye salt of the formula Z® (I) 15th 20th in which R ₁ and R _{2 are} a phenyl group or a phenyl group substituted by at least one alkyl or alkoxy group each having 1 to 6 carbon atoms, R _{3 is} an arylamino-substituted phenyl group or an alkylamino-substituted phenyl group each having 1 to 6 carbon atoms in the alkyl group, X sulfur, Oxygen or selenium and Z is an anion, and a hydrophobic binder with the repeating unit R ₈ -. (Ii) 35 40. contains, in the R ₄ . and R ₅ individually represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl radical, or R ₄ . and R ₅ together represent the carbon atoms required to form a cyclic hydrocarbon group, the total number of carbon atoms being up to 19, R ₆ and R ₇ each being hydrogen, alkyl or alkoxy groups each having 1 to 5 carbon atoms or a halogen atom and R _{8 being} a divalent group Group of formulas O S - O — C — O— —O — C — O— O O —C — O— -CO-CH ₂ - - O CH, - C - O - CH - O 45 50 55 60 -o — p — o— means. ■ ■ 3. · Photoconductive layer according to claim 2, characterized in that it. 4- [4-bis- (2-chloroethyl) aminophenyl] - 2,6-diphenylthiapyryliuniperchlorate, 4- (4-dimethylaminophenyl) -2,6-diphenyl- thiapyrylium fluorate,
4- (4-dimethylamino-2-methylphenyl) - 2,6-diphenylpyrylium perchlorate, 4- [4-di- (2-chloroethyl) aminophenyl] 2- (4-methoxyphenyl) -6-phenylthiapyry- lium perchlorate, 4- (4-dimethylaminophenyl) -2,6-diphenyl- ¹ thiapyrylium sulfate,
4- (4-dimethylaminophenyl) -2,6-diphenyl- thiapyrylium-p-toluenesulfonate, 4- (4-dimethylaminophenyl) -2,6-diphenyl-. pyrylium p-toluenesulfonate, 2,6-bis- (4-ethylphenyl) -4- (4-dimethyl- aminophenyl) thiapyrylium perchlorate, 4- (4-dimethylaminophenyl) -2- (4-methoxy- phenyl) -6-phenylthiapyrylium perchlorate, 4- (4-dimethylaminophenyl) -2- (4-ethoxyphenyl) -6-phenylthiapyrylium perchlorate or
4- (4-dimethylaminophenyl) -2,6-diphenylthiapyrylium perchlorate contains. 4. Photoconductive layer according to claim 2, characterized in that it is used as a binder a diarylalkane polycarbonate, poly [4,4 '- isopropylidene - bis (benzyl alcohol) -4,4' - isopropylidene dibenzoate] or poly (4,4'-isopropylidenediphenyl-4,4'-isopropylidenedibenzoate). 5. Photoconductive layer according to claim 4, characterized in that it is used as a binder a polycarbonate with repeating units of the formula R ₄ O —R — C — R — O — C — O— R ₅ contains, in which R represents a phenylene radical optionally substituted by a halogen atom or an alkyl radical and R ₄ and R ₅ individually each represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl radical or together represent the carbon atoms required to form a cyclic hydrocarbon group, where the total number of carbon atoms can be up to 19. 6. Photoconductive layer according to claim 1, characterized in that it is used as a photoconductor contains a di-, tri- or tetraarylalkane. 7. A method for producing a photoconductive layer in which a solution or suspension a photoconductor in a solution, a pyrylium, thiapyrylium or selenapyrylium dye salt and a hydrophobic binder applied to a layer support and is dried, characterized in that the dried photoconductive layer with a Solvent or with the vapor of a solvent is softened until at With a magnification of 2500 times under the microscope, segregation becomes visible, and that the segregation photoconductive layer is dried. 8. The method according to claim 7, characterized in that a halogenated solvent is used Hydrocarbon is used.