DE1522679B2 - Electrophotographic recording material - Google Patents

Description

is a photoconductive insulating material. Although the suggestion of a sensitized photoconductor per se in appears entirely useful from an economic point of view, it has the disadvantage that it is a restriction on materials that have significant photoconductivity.

The aforementioned three types of known plates are in U.S. Patents 2,999,750, 3,097,095, 3 113 022.3 041 165.3 126 281.3 073 861 and 3 072 479 and described in German Patent 1,068,115.

The prior art plates of the polymer type or of the binder type, the prepared using organic compounds generally have numerous disadvantages on how difficult and costly to manufacture, brittleness and poor adhesion to the carrier used pad. A part of these photoconductive layers also has a low thermal Resistance to what these plates are for use in automatic electrophotographic Devices that are often equipped with very powerful lamps and heating devices and thereby causing heating of the electrophotographic plate, makes it unusable. Furthermore the selection of certain physical properties is considerably limited by the fact that those used Materials must naturally have photoconductive properties.

Binder-type panels made using inorganic pigments are common opaque, which means that their use is limited to systems that allow light to pass through the plate is not required. In addition, these plates have the disadvantage that they cannot be used more than once. For this, on the one hand, their high fatigue strength and on the other hand to blame their rough surface, which makes cleaning the plate more difficult. Another The disadvantage is the restriction to materials that are inherently photoconductive.

The object of the invention was to provide an electrophotographic recording material which is essentially transparent and is therefore particularly suitable for systems that have a high Light transmission, which is also highly resistant to abrasion, require good thermal resistance has, can be deformed to self-supporting, binder-free layers and a base made of conductive material is not required. This object is achieved by the invention.

The invention thus provides a new electrophotographic recording material with a photoconductive layer which contains a charge transfer complex as a photoconductor, which thereby is characterized in that the charge transfer complex is a phenoxy resin as the electron donor contains.

According to a preferred embodiment, the charge transfer complex contains a phenoxy resin the general formula

H
HIGH

HHH

wherein X and Y are identical or different and represent a hydrogen atom or an alkyl group, the total number of carbon atoms in X and Y together being at most 12, and η = 2 or a larger integer.

For every 1 part of Lewis acid, 1 to 100 parts of the resin component can be used in the aforementioned complex omitted. At a ratio of 1 to 4 parts of resin component per 1 part of Lewis acid

ίο you get a material that is excellent photoconductive properties, especially at high sensitivity, very good for repeated Use is suitable. The best results could be achieved with a complex compound, as the Lewis acid 2,4,7-trinitro-9-fluorenone and as a resin component a condensation of epichlorohydrin with bisphenol-A [2,2- (4-bis-hydroxyphenyl) propane] obtained resin.

It should be noted that neither of the two components (A and B) is inherently photoconductive; rather, both components are not photoconductive. As soon as the transfer of the two aforementioned non-photoconductive components, namely the Lewis acid and the resin component into a complex by mixing or another suitable process, a photoconductive one is obtained - Insulating material which either deforms as a self-supporting layer or is placed on a suitable base can be knocked down. In addition, any other suitable method of production can also be used photoconductive plates made of the material described above can be used.

As was able to be established by the investigations on which the invention is based, it is possible to obtain from Naturally of non-photoconductive insulating materials of the electron donor type by forming a charge transfer complex to impart photoconductive properties with the transition of a pair of electrons. Every electron acceptor is a Lewis acid related to the other reagents present in the system. A Lewis acid tends to to take over a pair of electrons from an electron donor (Lewis base) and thus become a chemical one Compound or, in the case of the present invention, a charge transfer complex by charge transfer to build. In the present description, each is referred to in relation to the thus to complexing polymeric component known as a Lewis acid as an electron acceptor effective material.

A charge transfer complex can be defined as a molecular complex of essentially neutral electron donor and electron acceptor molecules, which is characterized by that when excited by photoenergy an internal electron transfer is produced, which is temporary creates an excited state in which the donor is more positive and the acceptor is more positive negative than in the ground state.

The insulating resins used in the teachings of the invention are believed to be of the donor type their photoconductivity through the formation of charge transfer complexes with electron acceptors (Lewis acids) obtained, and that these complexes, once formed, the photoconductive Form element of the panels.

In general, charge transfer complexes are structures with a relatively loose bond, the electron donation

gates and electron acceptors, often in stoichiometric proportions, and as follows can be characterized:

(A) The donor-acceptor interaction is only weak in the neutral ground state; i.e. neither the donor nor the acceptor is noticeably disturbed by the partner, as long as none Excitation takes place through the action of photo energy.

(B) The donor-acceptor interaction is relatively strong in the excited state; d. H. the Components are at least partially ionized as a result of the photoexcitation.

(C) Once the complex is formed, one or more new absorption bands appear nearby Ultraviolet or in the visible spectral range (wavelengths between 3200 and 7500 angstroms), which were neither present in the donor nor in the acceptor, but a specific property represent the shaft of the donor-acceptor complex formed.

It was found that both the donor and charge transfer specific bands based bands of the complex are suitable to induce photoconductivity.

The term "photoconductive insulator" is used in the context of the present invention in relation to the practical application in electrophotographic technology. Generally speaking, it can be practical placing each insulator in a photoconductive state; all that is required is a suggestion by radiation of sufficient intensity and sufficiently short wavelength. This fact holds true for both inorganic and organic materials and also includes inert resin binders, as used for binder boards, as well as those according to the teaching of the invention used activators of the electron acceptor type and the aromatic ones also used Resins.

In practice, short-wave radiation is used in electrophotographic technology not very advantageous, since radiation sources of sufficient intensity for wavelengths below 3200 angstroms are not available, such radiation is harmful to the human eye and also from those made of glass optical system is absorbed. Therefore, according to the teaching of the invention under »photoconductive Insulators «only understand materials that can be characterized as follows:

(1) These materials can be used to form coherent layers or films, which in are able to generate electrostatic radiation in the absence of hard, especially radioactive, radiation Withhold charge.

According to this definition, the resins proposed according to the teaching of the invention are and Lewis acids, insofar as they are used individually, are excluded.

The resins to be used according to the teaching of the invention are produced by condensation of epichlorohydrin obtained with suitable organic dihydroxy compounds. The best results will be at Use of bisphenol-A [2,2-bis- (4-hydroxyphenyl) propane] achieved for the production of the resin; this connection is therefore preferred according to the invention. In addition, other hydroxy compounds, such as. B. resorcinol, hydroquinone glycols, glycerin or Mixtures of these compounds are used together with or in place of hydroxyalkanes, However, the di- (mono-hydroxyaryl) alkanes, among which the aforementioned bisphenol-A in particular is preferred, are preferred.

According to the teaching of the invention, all di (monohydroxy) alkanes can be used. Specific examples of such compounds are (4,4'-dihydroxydiphenyl) methane, 2,2-bis- (4-hydroxyphenyl) -propane, 1,1- (4,4'-dihydroxydiphenyl) -cyclohexane, 1,1- (4,4'-dihydroxy-3,3'-dimethyldiphenyl) -cyclohexane , l, l- (2,2'-dihydroxy-4,4'-dimethyldiphenyl) butane, 2,2- (2,2'-dihydroxy-4,4'-di-tert-butyldiphenyl) propane, l, l '- (4,4'-Dihydroxydiphenyl) -l-phenylethane, 2,2- (4,4'-Dihydroxydiphenyl) -butane, 2,2- (4,4'-dihydroxydiphenyl) pentane, 3,3- (4,4'-dihydroxydiphenyl) pentane, 2,2- (4,4'-dihydroxydiphenyl) pentane, 2,2- (4,4'-Dihydroxydiphenyl) -hexane, 3,3- (4,4'-Dihydroxydiphenyl) -hexane, 2,2- (4,4-Dihydroxydiphenyl) -4-methylpentane, 4,4- (4,4'-dihydroxydiphenyl) heptane, 2,2- (4,4'-Dihydroxydiphenyl) -tridecane, 2,2- (4,4'-Dihydroxy-3'-methyldiphenyl) -propane, 2,2- (4,4'-Dihydroxy-3-methyl-3'-isopropyldiphenyl) butane, 2,2- (3,5,3 ', 5'-tetrachloro-4,4'-dihydroxydiphenyl) propane , 2,2- (3,5,3 ', 5'-tetrabromo-4,4'-dihydroxydiphenyl) propane, (3,3'-dichloro-4,4'-dihydroxydiphenyl) methane, (2,2'-Dihydroxy-5,5'-difluorodiphenyl) methane, (4,4'-Dihydroxydiphenyl) phenyl methane and l, l- (4,4'-dihydroxydiphenyl-l-phenylethane and mixtures of these compounds.

The basic chemical structure of phenoxy resins is

similar to that of epoxy resins. The phenoxy resins, however, can be viewed as a separate uniform class of resins and differ from the epoxies in several essential characteristics.
These differences include:

(1) The phenoxy resins do not have a terminal excellent in reactivity Epoxy groups. In addition, they are stable materials with unlimited Durability.

(2) Phenoxy resins are high molecular weight thermoplastic materials (about 30,000 im Compared to 340 to 4000 for epoxies) and are characterized by toughness and ductility.

(2) These layers or films are sufficiently sensitive to exposure to radiation with wavelengths over 3200 angstroms to reduce at least half of the existing charge ^{through a total absorption of at most 10 14} quanta per cm ^2.

(3) Phenoxy resins can be used as adhesives or coatings without any a chemical conversion would be necessary; d. H. they can do without catalysts, vulcanizing agents or hardeners are used.

A phenoxy resin prepared by the method described above is then mixed with a suitable Lewis acid converted into a Ladurigs transfer complex and thus forms the according to the invention photoconductive material.

Any suitable Lewis acid can be used to prepare the desired photoconductive material one of the aforementioned cardiac components can be converted into a complex compound. Although the mechanism of complex formation has not yet been fully clarified in the present case, it can be assumed that a charge transfer complex is formed by charge transfer which has absorption bands which do not apply to any of the complex-forming components if these considered individually, are characteristic. The one by mixing the two non-photoconductive ones Components induced synergistic effect seems to be much greater than that by a pure addition of the properties of the individual components to be achieved.

The best results can be achieved with the following, preferred Lewis acids. These include 2,4,7-trinitro-9-fluorenone, 4,4-bis- (dimethylamino) -benzophenone, tetrachlorophthalic anhydride, Chloranil, picric acid, benz (a) anthracene-7,12-dione, 1,3,5-trinitrobenzene.

Other typical Lewis acids are quinones ^ like - p-benzoquinone, 2,5-dichlorobenzoquinone, 2,6-dichlorobenzoquinone, Naphthoquinone- (1,4), 2,3-dichloronaphthoquinone- (1,4), anthraquinone, 2-methylanthraquinone, 1,4-dimethylanthraquinone, 1-chloianthraquinone, Anthraquinone-2-carboxylic acid, 1,5-dichloroanthraquinone, l-chloro-4-nitroanthraquinone, phenanthrenequinone, azenaphthenquinone, pyranthrenequinone, Chrysenequinone, thionaphthenquinone, anthraquinone-1,8-disulfonic acid and anthraquinone-2-aldehyde, triphthaloylbenzene, aldehydes such as bromal, 4-nitrobenzaldehyde, 2,6-dichlorobenzaldehyde, 2-ethoxy-l-naphthaldehyde, Anthracene-9-aldehyde, pyrene-3-aldehyde, oxindole-3-aldehyde, pyridine-2,6-dialdehyde and biphenyl-4-aldehyde, organic phosphonic acids, such as 4-ChloΓ-3-nitrobenzene phosphonic acid, nitrophenols, such as 4-nitrophenol and picric acid; Acid anhydrides, such as acetic anhydride, succinic anhydride, Maleic anhydride, phthalic anhydride, tetrachlorophthalic anhydride, perylene-3,4,9,10-tetracarboxylic acid and chrysene ^^. S.Q-tetracarboxylic anhydride, Di-bromomaleic anhydride, halides of metals and metalloids of groups IB, II to VIII of the periodic table of elements, such as: aluminum chloride, zinc chloride, ferric chloride, Tin tetrachloride, arsenic trichloride, tin (II) chloride, antimony pentachloride, magnesium chloride, Magnesium bromide, calcium bromide, calcium iodide, strontium bromide, chromium (III) bromide, manganese (II) chloride, Cobalt (II) chloride, cobalt (III) chloride, copper bromide, cerium chloride, thorium chloride, arsenic triiodide; Boron halides, such as boron trifluoride and boron trichloride, and ketones, such as acetophenone, benzophenone, 2-acetylnaphthalene, Benzil, benzoin, 5-benzoylacenaphthene, biacendione, 9-acetyl-anthracene, 9-benzoyl-anthracene, 4- (4-Dimethylaminocinnamoyl) -l-acetylbenzene, acetoacetic anilide, indanedione- (1,3), 1,3-diketohydrind, Acenaphthenequinone dichloride, bianisaldehyde, 2,2-pyridil and furil.

Other Lewis acids are mineral acids such as the hydrohalic acids, sulfuric acid and phosphoric acid; organic carboxylic acids such as acetic acid and substituted acetic acids, monochloroacetic acid, Dichloroacetic acid, trichloroacetic acid, phenylacetic acid and 6-methylcoumarinyl acetic acid- (4); Maleic acid, cinnamic acid, benzoic acid, l- (4-diethylaminobenzoyl) -benzene-2-carboxylic acid, Phthalic acid and tetrachlorophthalic acid, «, ^ - dibromo- ^ - formylacrylic acid, dibromomaleic acid, 2-bromobenzoic acid, gallic acid, 3-nitro-2-hydroxy-l-benzoic acid, 2-nitrophenoxyacetic acid, 2-nitrobenzoic acid, 3-nitrobenzoic acid, 4-nitrobenzoic acid, 3-nitro-4-ethoxybenzoic acid, 2-chloro-4-nitro-l-benzoic acid, 3-nitro-4-methoxybenzoic acid, 4-nitro-l-methylbenzoic acid, 2-chloro-5-nitro-l-benzoic acid, S-chloro-ö-nitro-l-benzoic acid, 4-chloro-3-nitro-l-benzoic acid, 5-chloro-3-nitro-2-hydroxybenzoic acid, 4-chloro-2-hydroxybenzoic acid, 2,4-dinitro-1-benzoic acid, 2-bromo-5-nitrobenzoic acid, 4-chlorophenylacetic acid, 2-chloro-cinnamic acid, 2-cyano cinnamic acid, 2,4-dichlorobenzoic acid, 3,5-dinitrobenzoic acid, 3,5-dinitrosalicylic acid, malonic acid, Mucic acid, acetosalicylic acid, benzilic acid, butanetetracarboxylic acid, citric acid, cyanoacetic acid, cyclohexanedicarboxylic acid, Cyclohexanecarboxylic acid,

9,10-dichlorostearic acid, fumaric acid, itaconic acid, levulinic acid, malic acid, succinic acid, α-bromostearic acid, citraconic acid, dibromosuccinic acid, pyrene-2,3,7,8-tetracarboxylic acid, tartaric acid, organic sulfonic acids such as 4-foluenesulfonic acid, 2, benzenesulfonic acid 4-dinitro-1-methylbenzene-6-sulfonic acid, 2,6-dinitro-1-hydroxybenzene-4-sulfonic acid, 2-nitro-hydroxybenzene-4-sulfonic acid, 4-nitro-1-hydroxy-2-benzenesulfonic acid, 3- Nitro-2-methyl-1-hydroxybenzene-5-sulfonic acid, δ-nitro-3-methyl-1-hydroxybenzene-2-sulfonic acid, 4-chloro-1-hydroxybenzene-3-sulfonic acid, 2-chloro-3-nitro-1 -methylbenzene-5-sulfonic acid and i-chloro-l-methylbenzene ^ -sulfonic acid.
The examples illustrate the invention.

Test procedure

to determine the photoconductivity given in the table below

The substance to be examined is placed on an electrically conductive carrier plate using a suitable method applied and dried. Earth potential is applied to the plate coated in this way, and the layer becomes electrical (positive or negative) in the dark by a corona discharge device up to saturation voltage charged using a needle point scorotron powered by a high voltage source is fed, which works with a voltage of 7 kV, while the grid voltage is below Use of a regulated DC voltage (0 to 1500V) output voltage source 0.9 kV is maintained. The loading time is 15 seconds.

The voltage applied to the plate as a result of the charge is then applied without touching the layer or the charge is changed, measured using a transparent electrometer probe. According to that The signal generated by the charge on the layer is amplified and sent to a Mosely autograph recorder fed. The curve recorded directly by the recording device shows the course of the size of the layer existing cargo and the charge reduction

409 531/284

on the time. After a period of about 15 seconds, the layer is exposed through the transparent button by means of light directed onto the layer, for which purpose a microscope lighting device is used, which has an incandescent lamp otherwise used for medical purposes, the light emitted has a color temperature of 2800 ^° K having. The illuminance is measured using a Weston light meter and is entered in the tables. The light discharge rate is measured over a period of 15 seconds or until a constant residual voltage is reached.

The numerical difference between the rate of charge depletion on the layer is in the dark during the exposure and the rate of charge degradation to be regarded as a measure of the photosensitivity of the layer.

With each material studied, the photoconductivity a practical experiment is also made. On the respective material there is a electrophotographic image produced in such a way that the material is subjected to a corona discharge is electrically charged that it is then exposed by projection according to a light-dark image and that the latent charged image is "developed by spraying" using a commercial developer is used, its applicability on the polarity of the previously applied to the photoconductive material applied charge is dependent. Details of this procedure are given in Example I.

The amount of the applied solution is chosen so that the layer thickness of the dried layer is about 5 μπι.

From the plate produced by the method described above, one is used as a test piece of 15.24x15.24 cm with a negative charge of about 450 volts with the help of a corona discharge. The plate is then exposed for 15 seconds. The exposure takes place by means of a projection device, which is equipped with an f / 4.5 lens and a tungsten light source, which is operated at 2950 ° K color temperature. The mean illuminance on the plate is about 43 lux as measured with a Weston light meter. Then will subjected the plate to cascade development using a developer composed of carbon black, a thermoplastic resin and sand coated with varnish as a carrier. The developed image is then transferred to a suitable base and fixed there by melting. That fixed The image is of good quality and corresponds to the projected original. Eventually the plate is from remaining Toner particles cleaned and can be used again in the manner described above.

Further specimens are made from the plate produced by the method described above tested with the help of an electrometer. The results of these investigations are summarized in the table.

Example II Example I.

35

In a glass beaker containing a solvent mixture consisting of about 80 parts dissolved Ethyl cellulose, about 90 parts of methyl ethyl ketone and about 30 parts of toluene, are about 30 parts Phenoxy resin, which was obtained by reacting bisphenol-A and epichlorohydrin and the following molecular structure

45

CH ₃ HHH "

»-O.-C — C-C-

CH _S H OH H η ₌ j ₀₀

has, registered. This mixture is then treated with stirring until the resin has dissolved completely resolved. Then about 0.1 part of 2,4,7-trinitrofluorenone in a solvent mixture, consisting of about 3 parts of cyclohexane and about 3 parts of toluene, dissolved and about 10 parts of the given above resin solution. This mixture is then mixed thoroughly with stirring to obtain a ensure homogeneous mixture.

The solution so prepared is then placed on a conductive pad, e.g. B. a shiny aluminum foil applied. For application, one can use methods known per se, such as brushing on, Operate immersion, pouring or centrifugal casting. The coating is then dried.

To produce the coating, a solution is prepared in the manner described in Example I, In contrast to Example I, instead of the Lewis acid used there, 0.25 part of 2,3-dichloro-1,4-naphthoquinone can be added to the resin solution. The solution is then applied to an aluminum base and dried. Of the The coating is then also provided with a negative charge by means of a corona discharge, exposed and developed in the manner described above. Then the developed image fixed on the plate by melting. The fixed image on the plate corresponds to the original and is characterized by sharpness, good contrast and a resolution of more than 20 line pairs per millimeter.

According to this procedure, another plate is made and tested with the help of an electrometer. The results are shown in the table.

Example III

To produce the coating, a solution is used in the manner described in Example I. set, with the difference from Example I 0.25 part of benz (a) anthracene-7,12-dione to the resin solution can be added. This solution is then in the manner described above on a conductive Pad applied and dried. Then an image corresponding to the original is created on the plate generated, which is characterized by sharpness, good contrast effect and a resolution of

more than 20 line pairs per millimeter. Another plate made by this process is tested with the help of an electrometer. The results of these investigations are in the table compiled.

The results obtained from Examples I to III show that coatings made from phenoxy resins are photoconductive if they have been complexed with a Lewis acid.

Example IV

A solution is prepared in the manner described in Example I, but with the addition a Lewis acid is dispensed with. The resin solution is also applied to a conductive pad and dried. The results of the electrometric investigation are shown in the table; she show that resin coatings which have not been treated with a Lewis acid are not photoconductive Have properties.

Comparative Example C

About 0.25 parts of benz (a) anthracene-7,12-dione are added to the solution prepared according to Comparative Example A added. The solution is applied to a conductive surface in a manner known per se applied and dried. Those obtained during the examination with the help of an electrometer ίο Results are shown in the table.

Comparative Example D.

About 0.25 parts of 2,3-dichloro-1,4-naphthoquinone are added to the solution prepared according to Comparative Example A added. This mixture is then in a known manner on a conductive pad applied and dried. The ones obtained in the subsequent electrometer test Results are shown in the table.

Example V

About 2 mg of a coating solution prepared in the manner described in Example I Brilliant green added. This release is also applied to a conductive surface and dried. A xerographic produced according to the method described in Example I Image is of excellent quality. The result of the electrometric examination is shown in the table listed. As can be seen from this, the addition of sensitizing dyes to the solution increased sensitivity in the visible range.

Comparative example A.

In a solvent mixture of about 10 parts of methyl ethyl ketone, about 1 part of benzene, about 1 part of acetone and about 2 parts of diethyl ketone, about 1 g of ethyl polymethacrylate (inherent viscosity of a 0.25 g of polymer in 50 ml of chloroform-containing solution at 25 ^° C. 91) solved. The mixture is stirred until the resin is completely dissolved in the solvent mixture. This solution is applied to an aluminum plate by a method known per se and dried. The results obtained when the plate was examined by means of an electrometer are shown in the table. From them it can be seen that the aforementioned ethyl polymethacrylate has no photoconductive properties.

This plate is used as control material for the following comparative examples B to E.

Comparative example B

About 0.25 parts of 2,4,7-trinitrofluorenone are added to the solution prepared according to Comparative Example A added. The mixture obtained is applied to a conductive base and dried. The results obtained when examined with the aid of an electrometer are shown in the table listed.

Comparative example E.

About 2 mg of brilliant green are added to the solution prepared according to Comparative Example A. The resulting mixture is then applied to a conductive pad and dried.

The results obtained in the subsequent electrometer test are shown in the table.

As can be seen from Comparative Examples A to E, the Lewis acids examined show and Sensitizer dyes in an inert binder, e.g. B. the one used in Comparative Example A. Polymethacrylic acid ethyl ester, no photoconductive properties.

In the table, the sensitivity is given as the initial rate of charge reduction on exposure, corrected by the charge reduction in the dark, designated, where the unit of measurement is volts / 100 lux. sec. is chosen.

As can be seen from Examples I to III, mixtures of a phenoxy resin and a Lewis acid photoconductive properties. In contrast, a phenoxy resin shows no Lewis acid added (Example IV) no photoconductive properties. Likewise, as comparative example A shows, the ethyl polymethacrylate used there is not photoconductive.

If Lewis acids or dyes that act as sensitizers are added to an inert binder, so they are also not photoconductive. This can be seen from Comparative Examples B to E, in which the Lewis acids and dyes used in Examples I to V in an inert binder (namely the ethyl polymethacrylate used in Comparative Example A) were investigated.

It was also found that there is the possibility of a phenoxy resin Lewis acid complex sensitize with the help of a suitable dye. The complexes of the invention can also be used in other imaging processes due to their excellent photoconductive properties, how they z. As described in British Patents 1,124,625 and 1,124,626.

Measurement results of the electrometric investigation photoconductive phenoxy resins

Tabel

example Initial potential Charge
dismantling at Charge
dismantling in Residual potential Layer- Lighting sensitivity
(Volt/
100 lux sec) I. (Volt) exposure
(Volts / sec) Dark
(Volts / sec) after 15 seconds QICKC
(μπ>) strength (lux) 0.93 +430 20.0 5.6 250 5. 146-3 1.86 II -450 21.3 0.0 265 0.93 +215 13.3 3.6 110 5 1463 1.86 III -270 26.7 1.5 110 0.93 +395 9.7 0.0 310 10 1463 0.93 IV -400 8.4 0.0 310 0 +450 0.0 0.0 450 5 1463 0 V -450 0.0 0.0 450 6.51 +295 93.3 4.1 60 5 1463 3.72 Comparison -270 62.3 4.4 70 example A. 0 +460 4.4 4.4 394 5 1463 0 B. -500 5.3 5.3 420 0 +310 3.3 3.3 260 7th 1463 0 C. -310 3.3 3.3 260 0 +380 3.0 3.0 335 7th 1463 0 D. -470 4.0 4.0- 410 0 +320 1.6 ^ -1.6 * 290 5 1463 0 E. -320 4.5 4.5 225 0 +350 2.7 2.7 310 5 1463 0 -325 1 1 315

Claims (4)

X HHH -0- <f ^ -C- / ^ -O-C-C-C- ι I HOH J 2 is recorded in the areas of the layer that claims: still have a charge, i.e. in the unexposed areas. This creates a powder image, 1. Electrophotographic recording medium in its configuration entterial to the latent image with a photoconductive layer speaking as 5. This powder image can then be printed on paper or Photoconductors transfer a charge transfer complex and other suitable material on this contains, characterized in that the substrate by a heat treatment or by the charge transfer complex can be fixed as electrons- other suitable measures. That donator contains a phenoxy resin. The aforementioned general procedure is also in the 2. Recording material according to claim 1, U.S. Patents 2,357,809,2 891011 and 3,079,342 characterized in that the charge over-described. Carrying complex a phenoxy resin of the formula is known to be numerous different types photoconductive insulating materials can be used to make electrophotographic plates. Suitable photoconductive materials such as anthracene, sulfur, selenium or mixtures of these materials have already been mentioned in US Pat. No. 2,297,691. The spectral sensitivity of these materials is mainly in the blue spectral range 20 as well as in the near ultraviolet. In addition, those in which X and Y are the same or different can be used for these materials and a hydrogen atom or an alkyl is limited in that they, with the exception of selenium, only mean a few groups, the total number of which are photosensitive. For this reason, for carbon atoms in X and Y taken together, at most commercial purposes, selenium is mainly used for which 12 and η is 2 or more than the number of electrophotographic plate making. . det. Although vitreous selenium in many ways is considered 3. Recording material according to claim 1-Tind "is to be regarded as a preferred material, it has numerous 2, characterized in that the charge disadvantages. One of these is the limited one transmission complex a through conversion of spectral yield in ultraviolet, blue and Epichlorohydrin with 2,2-bis- (4-hydroxyphenyl) -pro- 30 green area of the spectrum, on the other hand the at pan contains phenoxy resin. the manufacture of panels, using 4. Recording material according to claim 1, vitreous selenium required and consuming characterized in that the charge overcomplicated process steps, such as vapor deposition Carrying complex as an electron acceptor 2,4,7-tri-selenium layer in a vacuum. Another disadvantage is contains nitro-9-fluorenone. 35 can be seen in the fact that selenium plates with an additional, must be equipped with a carrier layer of conductive material separated from the selenium layer, wherein expediently on this carrier layer before Deposition of the photoconductive selenium an additional separating or barrier layer is applied The invention relates to an electrophotographic should be. This economic and technolo-record material With a photoconductive gical considerations were the occasion for numerous layers, which as a photoconductor a charge transfer effort for the development of other photoconductive complexes contains. of the insulating materials as selenium, which are used for the manufacture As is known, on the surface of certain 45 electrophotographic plates,
photoconductive materials with the help of electrostatic It was z. B. proposed to manufacture Means images are created and developed. The photoconductive insulating layers for electrophotographic electrophotographic Basic process, as described in the phische Platten different two-component systems USA.-Patent 2 297 691 in order to use. So it is B. known for the production holds several procedural steps. First, a 50 photoconductive insulating layer becomes a photophotoconductive dispersion Insulating layer with a uniform conductive inorganic pigment in a suitable binding charge provided and then to use with a medium. It could still be shown different densities exhibiting image are exposed that for the production of photoconductive insulating, whereby in the exposed areas of the layers for plates of the binder type photo plate the charge is reduced. The in this way 55 conductive organic dyes as well as a large number latent polycyclic compounds formed on the photoconductive layer in association with electronic picture corresponds in its configuration suitable resins can be used. Included the image used for exposure. Another requirement for each of the two systems is that Possibility to generate a latent electro- at least one of the original ones, to manufacture static image consists in the fact that the plate corresponds to 60 the photoconductive insulating layer used a certain predetermined image components themselves is a photoconductive material. at being charged. The latent image is then placed in a third type of plate, polymers are used visible image in which the latent ones are inherently photoconductive. These are coming Image-bearing layer finely divided developer - often together with sensitizing dyes material is knocked down. The developer 65 or with Lewis acids for making photomaterial generally consists of one used as a conductive insulating layer. Also at Toner called dye and a carrier material this type of plate is used to form the photoconductive for the toner. The powdered developer material layer required that at least one component