CA1259517A - Electrophotographic recording material - Google Patents
Electrophotographic recording materialInfo
- Publication number
- CA1259517A CA1259517A CA000481002A CA481002A CA1259517A CA 1259517 A CA1259517 A CA 1259517A CA 000481002 A CA000481002 A CA 000481002A CA 481002 A CA481002 A CA 481002A CA 1259517 A CA1259517 A CA 1259517A
- Authority
- CA
- Canada
- Prior art keywords
- recording material
- layer
- weight
- type conducting
- photoconductive layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
- G03G5/02—Charge-receiving layers
- G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
- G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
- G03G5/0601—Acyclic or carbocyclic compounds
- G03G5/0609—Acyclic or carbocyclic compounds containing oxygen
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
- G03G5/02—Charge-receiving layers
- G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
- G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
- G03G5/0622—Heterocyclic compounds
- G03G5/0644—Heterocyclic compounds containing two or more hetero rings
- G03G5/0646—Heterocyclic compounds containing two or more hetero rings in the same ring system
- G03G5/0657—Heterocyclic compounds containing two or more hetero rings in the same ring system containing seven relevant rings
Abstract
ABSTRACT OF THE DISCLOSURE
An electrophotographic recording material is disclosed comprising an electrically conductive sup-port, a photoconductive layer and, optionally, an insu-lating barrier layer between the substrate and photoconductive layer. The photoconductive layer comprises at least one organic, n-type conducting pigment in a concentration between 10 and 50, pre-ferably between 15 and 30, percent by weight, relative to the photoconductive layer weight, at least one electronically inert, carbonyl group-containing binder and an organic, p-type conducting photoconductor in a concentration from 0 to 20, preferably from 2 to 8 per-cent by weight, relative to the photoconductive layer weight. The n-type conducting pigment preferably comprises a compound selected from the trans-perinones, the perylene-tetracarboxylic acid diimides, and the condensed quinones.
An electrophotographic recording material is disclosed comprising an electrically conductive sup-port, a photoconductive layer and, optionally, an insu-lating barrier layer between the substrate and photoconductive layer. The photoconductive layer comprises at least one organic, n-type conducting pigment in a concentration between 10 and 50, pre-ferably between 15 and 30, percent by weight, relative to the photoconductive layer weight, at least one electronically inert, carbonyl group-containing binder and an organic, p-type conducting photoconductor in a concentration from 0 to 20, preferably from 2 to 8 per-cent by weight, relative to the photoconductive layer weight. The n-type conducting pigment preferably comprises a compound selected from the trans-perinones, the perylene-tetracarboxylic acid diimides, and the condensed quinones.
Description
1:~5~L7 EL~CTROPHOTOGRAPHIC RECORDING MATERIAL
BACKGROUND OF THE INVENTION
The present invention relates to an electro-photographic recording material comprising an electri-cally conductive support, a photoconductive layer and,optionally, an insulating barrier layer between the support and the photoconductive layer. The recording material is suitable for repeated or single use in copiers, and for use as a printing plate or a printed circuit.
German Auslegeschrift No. 11 17 391 (corres-ponding to British Patent No. 944,126) discloses the manufacture of electrophotographic recording materials, using photoconductive, predominantly low-molecular weight, organic p-type conducting compounds which are sensitized in the visible region of the spectrum by means of (a) suitable, dissolved dyes, as described in German Offenlegungsschrift No. 25 26 720 (corresponding to U.S. Patent No. 4,063~948), or (b) dispersed photo-conductive color pigments, as described in German Auslegeschrift No. 21 08 939 (corresponding to U.S.
Patent No. 3,870,516).
As the charge-carrier generating color pigments, perinones, as specified in German 25 Offenlegungsschrift No. 22 39 923 tcorresponding to British Patent No. 1,416,603) and in German Offenlegungsschrift No. 21 08 958 (corresponding to U.S. Patent No. 3,879,200), perylene tetracarboxylic .. 1-~ 25~5~
acid diimides, as speciEied in German Offenlegungs-schriften No. 22 37 539 (corresponding to U~S. Patent - No. 3,~71,882) and No. 21 08 992 (corresponding to U.S.
Patent No. 3,904,407), and condensed quinones, as spec-ified in German Offenlegungsschriften No. 22 37 678 (corresponding to U.S. Patent No. 4,315,981) and No. 21 08 935 (corresponding to U.S. Patent No. 3,877,935) are used, among others. The a-bove-described systems have in common a double layer arrangement comprised of a thin charge-carrier generating bottom layer containing a high concentration of color pigment and a relatively thick charge transport layer containing an inert binder and an or-ganic p-type ~onducting photoconductor.
Layer arrangements are also disclosed in which the sensitizing color pigment and the p-type conducting photoconductor are applied, together in one layer, to the electrically conductive support. According to U.S.
Patent No. 3,879,200, for example, the concentration of color pigment required to achieve optimum physical and electrical properties amounts to only 0.1 to 5% by volume of the photoactive layer. On the other hand, the organic p-type conducting photoconductor, comprising aromatic or heterocyclic compounds, must be present in the layer in a concentration of at least 25%
by volume, to obtain practicable sensitivities. The binders which are described include electronically inert polymers, such as polystyrene, polyacrylate, cellulose nitrate, polyvinyl acetate, chlorinated rubber, etc.
Moreover, electrophotographic layers are known, which comprise a photoconductive pigment and an electronically inert binder. As the photoconductive pigments, zinc oxide, according to U.S. Patent 35 No. 3,121,006, cadmium sulfide, according to U.S.
Patent No. 3,238,150, and a number of other inorganic ~;25~5~7 compounds are described. In these layers, charge transport is achieved by a high concentration of the - photoconductive pigment. A layer composition of this kind requires a pigment concentration exceeding 50% by volume to permit contact between the photoconductive particles. According to German Offenlegungsschrift No. 32 27 475 (corresponding to U.S. Patent No. 4,418,134), organic photoconductive pigments can be substituted for part of the inorganic pigment, and for this purpose, pigments such as C.I. Pigment Red 168 and C.I. Pigment Orange 43, which represent derivatives of naphthalene tetracarboxylic acid diimides, have proved suitable. The total proportion of photoconductor in the layer, which is necessary for practical applica-tion, is then in the range between 20 and 80% by weight. In view of an application in electrophoto-graphic offset-printing plates, polymers which are decoatable with or dispersible in alkaline solutions are required as the binders.
Because light absorption and charge-carrier generation occur, in particular, in the upper region of the layer, and because transport characteristics are different for electrons and "holes~' ("n-type photo-conductors"), a good sensitivity of zinc oxide layers is only observed if a negative charge is applied. With positive charging, on the other hand, good sen-sitivities are obtained in monolayer photoconductor systems which contain, in addition to an inert binder, a metal-free phthalocyanine in the X-form (see German Ofenlegungsschrit No. 14 97 205, corresponding to U.S. Patent No. 3,816,118). The req~ired pigment con-centration between 5 and 25% by weight is clearly below the value assumed or contact between the pigment par-ticles.
In an analogous manner, monolayers for posi-tive charging can be prepared from copper phthalo-~ r ~ ~
cyanine in the ~ -form (Japanese patent application No. 50/38543, published after examination).
- From Japanese patent application No. 49/76933, published after examination, it is known that the pigment C.I. Pigment Orange 43 (= C.I. Vat Orange 7) can be converted into a photoconductive form by reacting it with 2,4,7,8-tetranitrocarba~ole. The resulting ~ -complex shows good sensitivities in com-bination (50:50) with poly-N-vinyl-car~azole as a binder having the properties of a p-type conducting photoconductor.
To achieve high photosensitivities in the case of negative charging, photoconductors in double-layer arrangement are used. But this arrangement has the disadvantage of being produced in two steps of coating application, which is more expensive than the produc-tion of a monolayer material. Double-layer arrange-ments also have the disadvantage of showing an unfavorable residual-charge behavior. Monolayers based on zinc oxide, on the other hand, have low residual charge potentials and can be used for cyclic image reproduction. But due to the high proportion of zinc oxide, layers of this kind show a relatively low mecha-nical stability and a relatively poor charge accep-tance.
Decoatability of the photoconductor layer inthe non-image areas, after imaging and fixing the toner image, is a decisive criterion of usefulness in the production of electrophotographic printing plates or printed circuits. As a consequence, photoconductor layers in double layer arrangements containing extreme-ly high pigment proportions are not readily employed in this context.According to published European Patent Application EP-A- 0 137 217, double layer photoconductors which are formed of two layers of approximately equal thickness, i.e., a precoating comprising a pigment and lZ5~5~ .
a binder and a covering coating comprising a p-type conducting photoconductor and a binder, can be used for ~ the electrophotographic production of offset printing plates, but they are clearly less sensitive than the first-mentioned photoconductor layers, and are also unfavorable from the point of view of production expense.
~onolayer photoconductors containing dissolved sensitizing dyes, as disclosed by German Offenlegungsschrift No. 25 26 720 (corresponding to U.S. Patent No. 4,063,948), have similar sensitivities but, in contrast to the pigment layers, are sensitive to pre-exposure, i.e., their charge acceptance is noti-ceably impaired by preliminary exposure. Monolayers15 containing low concentrations of sensitizing pigments show photosensitivities which are markedly lower than those of double layers and also poorer image reproduc-tions. All of the above-described layer arrangements, however, exhibit unwelcome, relatively large residual potentials after exposure, which potentials rise drastically with increasing layer thickness and lead to difficulties in rendering visible the latent charge image.
For use as electrophotographic resists, mono-layers comprising a binder, a dissolved dye or pigment, and a p-type conducting photoconductor are only appli-cable by laminating processes. Because of the high proportion of photoconductor in such layers, direct application to metals, such as copper or iron, oEten leads to contamination of the layer or surEace and, thus, to a considerably reduced charge acceptance which severely hampers practical use. By means of double layers which do not contain a p-type conducting photo-conductor in the pre-coating, these effects can be obviated, but the above-mentioned disadvantages thus appear.
~:25~5~7 ~UYA~ O~ IN~ENTION
It is therefore an object of the present inven-- tion to provide an electrophotographic recording material which can be used for the production of both printing plates and printed circuits (circuit boards), but which incorporates a low concentration of the p-type conducting photoconductor with a specific class oE
binder material.
It is another object of the present invention to provide an electrophotographic recording material which can be easily and inexpensively produced, which shows a high photosensitivity and high voltage contrasts, at a good negative charge acceptance, and which retains low residual potentials after exposure.
It is a further object of the present inven-tion to provide an electrophotographic recording material having the properties set out in the preceding paragraph that also incorporates a flexible support and can be used in a lamination process.
In accomplishing the foregoing objects~ there has been provided, in accordance with one aspect of the present invention, an electrophotographic recording material comprising an electrically conductive support and a photoconductive layer, wherein said photoconduc-tive layer comprises (a) at least one organic, n-type conducting pigment in a concentration between about 10 and 50 percent by weight, relative to the layer weight of the photoconductive layer, tb) at least one electron-ically inert, carbonyl group-containing binder, and (c) an organic, p-type conducting photoconductor in a concentration from about 0 to 20 percent by weight, relative to the layer weight of the photoconductive layer. In one preferred embodiment, the aforesaid binder comprises a copolymer comprised of a methacrylic acid ester and methacrylic acid.
Other objects, features, and advantages of the present invention will become apparent from the 1~5~
following detailed description. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodi-ments of the invention, are given by way of illustra-tion only, since various changes and modificationswithin the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
DETAILED DESCRIPTI~N OF THE PREFERRED EMBODIMENTS
An organic p-type conducting photoconductor can be homogeneously distributed in the photoconductive layer of the present invention. The photoconductor can also be distributed through the photoconductive layer in a gradient resulting from diffusion of the photocon-ductor into the layer, or in a stepped distribution resulting from a double layer arrangement.
As suitable n-type conducting pigments, com-pounds corresponding to the following general formulas I to IV can be used;
BACKGROUND OF THE INVENTION
The present invention relates to an electro-photographic recording material comprising an electri-cally conductive support, a photoconductive layer and,optionally, an insulating barrier layer between the support and the photoconductive layer. The recording material is suitable for repeated or single use in copiers, and for use as a printing plate or a printed circuit.
German Auslegeschrift No. 11 17 391 (corres-ponding to British Patent No. 944,126) discloses the manufacture of electrophotographic recording materials, using photoconductive, predominantly low-molecular weight, organic p-type conducting compounds which are sensitized in the visible region of the spectrum by means of (a) suitable, dissolved dyes, as described in German Offenlegungsschrift No. 25 26 720 (corresponding to U.S. Patent No. 4,063~948), or (b) dispersed photo-conductive color pigments, as described in German Auslegeschrift No. 21 08 939 (corresponding to U.S.
Patent No. 3,870,516).
As the charge-carrier generating color pigments, perinones, as specified in German 25 Offenlegungsschrift No. 22 39 923 tcorresponding to British Patent No. 1,416,603) and in German Offenlegungsschrift No. 21 08 958 (corresponding to U.S. Patent No. 3,879,200), perylene tetracarboxylic .. 1-~ 25~5~
acid diimides, as speciEied in German Offenlegungs-schriften No. 22 37 539 (corresponding to U~S. Patent - No. 3,~71,882) and No. 21 08 992 (corresponding to U.S.
Patent No. 3,904,407), and condensed quinones, as spec-ified in German Offenlegungsschriften No. 22 37 678 (corresponding to U.S. Patent No. 4,315,981) and No. 21 08 935 (corresponding to U.S. Patent No. 3,877,935) are used, among others. The a-bove-described systems have in common a double layer arrangement comprised of a thin charge-carrier generating bottom layer containing a high concentration of color pigment and a relatively thick charge transport layer containing an inert binder and an or-ganic p-type ~onducting photoconductor.
Layer arrangements are also disclosed in which the sensitizing color pigment and the p-type conducting photoconductor are applied, together in one layer, to the electrically conductive support. According to U.S.
Patent No. 3,879,200, for example, the concentration of color pigment required to achieve optimum physical and electrical properties amounts to only 0.1 to 5% by volume of the photoactive layer. On the other hand, the organic p-type conducting photoconductor, comprising aromatic or heterocyclic compounds, must be present in the layer in a concentration of at least 25%
by volume, to obtain practicable sensitivities. The binders which are described include electronically inert polymers, such as polystyrene, polyacrylate, cellulose nitrate, polyvinyl acetate, chlorinated rubber, etc.
Moreover, electrophotographic layers are known, which comprise a photoconductive pigment and an electronically inert binder. As the photoconductive pigments, zinc oxide, according to U.S. Patent 35 No. 3,121,006, cadmium sulfide, according to U.S.
Patent No. 3,238,150, and a number of other inorganic ~;25~5~7 compounds are described. In these layers, charge transport is achieved by a high concentration of the - photoconductive pigment. A layer composition of this kind requires a pigment concentration exceeding 50% by volume to permit contact between the photoconductive particles. According to German Offenlegungsschrift No. 32 27 475 (corresponding to U.S. Patent No. 4,418,134), organic photoconductive pigments can be substituted for part of the inorganic pigment, and for this purpose, pigments such as C.I. Pigment Red 168 and C.I. Pigment Orange 43, which represent derivatives of naphthalene tetracarboxylic acid diimides, have proved suitable. The total proportion of photoconductor in the layer, which is necessary for practical applica-tion, is then in the range between 20 and 80% by weight. In view of an application in electrophoto-graphic offset-printing plates, polymers which are decoatable with or dispersible in alkaline solutions are required as the binders.
Because light absorption and charge-carrier generation occur, in particular, in the upper region of the layer, and because transport characteristics are different for electrons and "holes~' ("n-type photo-conductors"), a good sensitivity of zinc oxide layers is only observed if a negative charge is applied. With positive charging, on the other hand, good sen-sitivities are obtained in monolayer photoconductor systems which contain, in addition to an inert binder, a metal-free phthalocyanine in the X-form (see German Ofenlegungsschrit No. 14 97 205, corresponding to U.S. Patent No. 3,816,118). The req~ired pigment con-centration between 5 and 25% by weight is clearly below the value assumed or contact between the pigment par-ticles.
In an analogous manner, monolayers for posi-tive charging can be prepared from copper phthalo-~ r ~ ~
cyanine in the ~ -form (Japanese patent application No. 50/38543, published after examination).
- From Japanese patent application No. 49/76933, published after examination, it is known that the pigment C.I. Pigment Orange 43 (= C.I. Vat Orange 7) can be converted into a photoconductive form by reacting it with 2,4,7,8-tetranitrocarba~ole. The resulting ~ -complex shows good sensitivities in com-bination (50:50) with poly-N-vinyl-car~azole as a binder having the properties of a p-type conducting photoconductor.
To achieve high photosensitivities in the case of negative charging, photoconductors in double-layer arrangement are used. But this arrangement has the disadvantage of being produced in two steps of coating application, which is more expensive than the produc-tion of a monolayer material. Double-layer arrange-ments also have the disadvantage of showing an unfavorable residual-charge behavior. Monolayers based on zinc oxide, on the other hand, have low residual charge potentials and can be used for cyclic image reproduction. But due to the high proportion of zinc oxide, layers of this kind show a relatively low mecha-nical stability and a relatively poor charge accep-tance.
Decoatability of the photoconductor layer inthe non-image areas, after imaging and fixing the toner image, is a decisive criterion of usefulness in the production of electrophotographic printing plates or printed circuits. As a consequence, photoconductor layers in double layer arrangements containing extreme-ly high pigment proportions are not readily employed in this context.According to published European Patent Application EP-A- 0 137 217, double layer photoconductors which are formed of two layers of approximately equal thickness, i.e., a precoating comprising a pigment and lZ5~5~ .
a binder and a covering coating comprising a p-type conducting photoconductor and a binder, can be used for ~ the electrophotographic production of offset printing plates, but they are clearly less sensitive than the first-mentioned photoconductor layers, and are also unfavorable from the point of view of production expense.
~onolayer photoconductors containing dissolved sensitizing dyes, as disclosed by German Offenlegungsschrift No. 25 26 720 (corresponding to U.S. Patent No. 4,063,948), have similar sensitivities but, in contrast to the pigment layers, are sensitive to pre-exposure, i.e., their charge acceptance is noti-ceably impaired by preliminary exposure. Monolayers15 containing low concentrations of sensitizing pigments show photosensitivities which are markedly lower than those of double layers and also poorer image reproduc-tions. All of the above-described layer arrangements, however, exhibit unwelcome, relatively large residual potentials after exposure, which potentials rise drastically with increasing layer thickness and lead to difficulties in rendering visible the latent charge image.
For use as electrophotographic resists, mono-layers comprising a binder, a dissolved dye or pigment, and a p-type conducting photoconductor are only appli-cable by laminating processes. Because of the high proportion of photoconductor in such layers, direct application to metals, such as copper or iron, oEten leads to contamination of the layer or surEace and, thus, to a considerably reduced charge acceptance which severely hampers practical use. By means of double layers which do not contain a p-type conducting photo-conductor in the pre-coating, these effects can be obviated, but the above-mentioned disadvantages thus appear.
~:25~5~7 ~UYA~ O~ IN~ENTION
It is therefore an object of the present inven-- tion to provide an electrophotographic recording material which can be used for the production of both printing plates and printed circuits (circuit boards), but which incorporates a low concentration of the p-type conducting photoconductor with a specific class oE
binder material.
It is another object of the present invention to provide an electrophotographic recording material which can be easily and inexpensively produced, which shows a high photosensitivity and high voltage contrasts, at a good negative charge acceptance, and which retains low residual potentials after exposure.
It is a further object of the present inven-tion to provide an electrophotographic recording material having the properties set out in the preceding paragraph that also incorporates a flexible support and can be used in a lamination process.
In accomplishing the foregoing objects~ there has been provided, in accordance with one aspect of the present invention, an electrophotographic recording material comprising an electrically conductive support and a photoconductive layer, wherein said photoconduc-tive layer comprises (a) at least one organic, n-type conducting pigment in a concentration between about 10 and 50 percent by weight, relative to the layer weight of the photoconductive layer, tb) at least one electron-ically inert, carbonyl group-containing binder, and (c) an organic, p-type conducting photoconductor in a concentration from about 0 to 20 percent by weight, relative to the layer weight of the photoconductive layer. In one preferred embodiment, the aforesaid binder comprises a copolymer comprised of a methacrylic acid ester and methacrylic acid.
Other objects, features, and advantages of the present invention will become apparent from the 1~5~
following detailed description. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodi-ments of the invention, are given by way of illustra-tion only, since various changes and modificationswithin the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
DETAILED DESCRIPTI~N OF THE PREFERRED EMBODIMENTS
An organic p-type conducting photoconductor can be homogeneously distributed in the photoconductive layer of the present invention. The photoconductor can also be distributed through the photoconductive layer in a gradient resulting from diffusion of the photocon-ductor into the layer, or in a stepped distribution resulting from a double layer arrangement.
As suitable n-type conducting pigments, com-pounds corresponding to the following general formulas I to IV can be used;
2~ trans-perinones:
perylene tetracarboxylic acid diimides:
I? - ~ (II) ~,`.
~25~5~7 condensed quinones:
n~ ' ï (III) ~ (IV) in which R denotes a hydrogen, a phenyl radical or - an alkyl radical having frcm one to four carbon atoms, which may be substituted by halogen, an alkyl group or an alkoxy group, R' stands for halogen, such as chlorine or bromine, for the nitro group, the cyano ~ group, or an alkoxy group, and n is an integer between one and four.
In a number of publications, these pigments are referred to as being photoconductive. In this con-text, however, "photoconductivity~ is invariably understood as being based on interaction with other photoconductors. The color pigments thus play the role of a sensitizer which generates charge carriers in interaction with the p-type conducting photoconductor.
Accordingly, pigments are either used in very thin, charge-carrier generating layers or, in the case of homogeneous distribution, in a relatively low con-centration. According to U.S. Patents No. 3,879,200 lZ5~5~'7 and No. 3,904,407, good electrophotographic properties can only be achieved when these conditions are met.
But, to the contrary, it has now been found, in accordance with the present invention, that recording materials containing pigments represented by formulas I to IV in sufficiently high concentrations (which approximate those described for the phthalo-cyanines of German Offenlegungsschrift No. 14 97 205, mentioned above) are photoconductive even if a p-type conducting photoconductor has not been added to the layer. Widely varying behavior observed with positive and negative charging, respectively, indicates a pro-nounced n-type conductivity for these pigments. As in ZnO, good sensitivities can be achieved only with nega-tive charging.
Based on what was known previously of thepigments which are used according to the present inven-tion, it was unexpected to find a pronounced dependency of the electrophotographic properties of the layer on the binder employed. Thus, good sensitivities could only be obtained when binders were used which comprised a carbonyl group, for example, in the form of the car-boxyl group. Nitrocellulose, on the other hand, which normally is a binder having particularly favorable electrophotographic properties, proved to be extremely unfavorable in the photoconductive layer of the present invention; t:he same was true, for example, for polystyrene. The influence of the ~inder remains undi-minished even if, according to the present invention,30 p-type conducting photoconductors are added to the layer in the indicated quantities.
As in zinc oxide layers, a strong "trap"
effect, occurring in the initial phase of discharge, is observed in part of the photoconductive layers of the present invention, leading to an S-shaped discharge curve instead of the approximately exponential ~ 7 discharge characteristic normally obtained in org~nic photoconductor systems (see, for example, German Patent ~o. ~2 37 539). This S-shaped discharge characteristic yields particularly high voltage contrasts in the region of average exposure energies. As a consequence, the photoconductive layers of the present invention can be used for the production of charge images and toner images which have a particularly steep gradation and a particularly high resolution.
Utilization of the n-type conductivity of pigments employed according to the present invention requires a minimum pigment concentration of approxima-tely 10 percent by weight, based on the layer weight.
Pigment concentrations which are too high lead to a deterioration of charge acceptance and, consequently, a pigment content of about 50 percent by weight is regarded as an approximate upper limit. Pigment con-centrations between 15 and 30 percent by weight have proved to be particularly advantageous. These pigment concentrations, particularly concentrations in the upper end of the range, ensure decoatability of the photoconductive layer for application in making electrophotographically imageable printing plates and the like, if the alkali-soluble binders according to the present invention are employed.
When n-type conducting pigments are used in accordance with the present invention, an increase in sensitivity is obtained if minor amounts of p-type con-ducting photoconductors are added to the photoconductor30 layer. The p-type conducting photoconductor compounds that are customarily employed in electrophotographic layers are suitable in this regard. Examples of such compounds are oxdiazoles, oxazoles, aromatic amines, triphenyl methanes and hydrazones, and also polymeric compounds, such as polyvinyl-carbazole, as described, for example, in German Patents No. 10 58 836, No. 10 60 260~ No. 11 20 875, No. 11 97 325, No. 1~ 68 115t and No. 11 11 935.
In order to ensure good charge acceptance of the photoconductive layer, the concentration of the p-type conducting photoconductor should not e~ceed 20percent by weight, based on the layer weight.
Concentrations between 2 and 8 percent by weight have proved particularly favorableO
The p-type conductivity of the photoconductor contributes to charge-carrier generation and transport of positive charge carriers only in the upper region of the photoconductor layer. According to the present invention, the addition of p-type conducting photocon-ductor can therefore be limited to these upper zones,15 and the addition of p-type conducting photoconductor in the upper layer region has proved advantageous too,par-ticularly in the case o~ thicker layers. A systematic introduction of the p-type conducting photoconductor into the upper layer regions can be achieved either by a double layer arrangement or by post-treating the final layer, which does not yet contain the p-type con-ducting photoconductor, with corresponding solutions of the photoconductor, which are applied without binder.
By partially dissolving the binder and then diffusing the p-type conducting photoconductor into the upper region of the layer, photosensitivities are obtained that correspond to the photosensitivities of homoge-neously doped layers. Five percent strength solutions, for example, in tetrahydrofuran, have proved suitable for application.
Polymers with C-0-containing side groups, and also polycondensates and polyaddition compounds having C=O groups in the principal chain, are suitable as the electronically inert, carbonyl group-containing binders in the present invention~ Good photosensitivities are achieved USill9 homopolymers and copolymers of vinyl ` , -11-1259~,t7 esters, of acrylic acid esters and methacrylic acid esters, of acxylic acid and methacrylic acid, of vinyl ketones, of acrylic acid amides and methacrylic acid amides, and also using polyesters, polycarbonates, polyurethanes, ~olyamides and polyureas. Due to their mechanical properties, polyesters and polycarbonates ~re particularly suitable for use in flexible photocon-ductors.
For the production of printing plates, electronically inert, carbonyl group-containing binders are used in the present invention which are soluble or dispersible in aqueous-alkaline solutions. For this purpose, it is preferred to use copolymers of methacry-lic acid esters and methacrylic acid, optionally with15 additional monomers, such as acrylic acid and styrene.
These copolymers have proved superior to alkali-soluble ~inders based on acrylic acid and acrylic acid esters or on vinyl acetate and crotonic acid, respectively.
In particular, charge acceptance is higher in the pre-ferred copolymers, while photosensitivity is unchanged but these copolymers are also superior with regard to the criteria of fixability of the toner image obtained on the photoconductive layer, decoatability, and sub-sequent print run. Copolymers displaying a glass tran-sition temperature of ~ 40 C are particularly advantageous for the production of printing plates.
For use in an electrophotographic dry resist, only those binders are suitable that have a substan-tially lower glass transition temperature. Only when30 the glass transition temperature is substantially lower than 40 C can a complete transEer by lamination of the photoconductive layer be achieved. Binders which have proved particularly suitable include copolymers obtained from the monomers selected from acrylic acid, longer-chain acrylic acid esters and methacrylic acid esters, in combination (when appropriate) with addi-~2S95~7 tionaL monomers, such as methacrylic acid and styrene.
For an application in the form of a liquid resist, there are no limitations concerning the glass tran-sition temperature of the binder.
The thickness of the photoconductive layer depend~, in the first instance, on the intended use.
In order to ensure sufficient charge acceptance, the layer weight should not be below about 3 g/m~. For use as a liquid resist or for the production of electropho-tographic printing plates, the layer weight is appropriately between about 5 and 30 g/m2, for photo-conductor webs or drums in copiers between about 10 and 20 g/m2, and for a laminatable material between about 20 and 50 g/m2. A steep rise of the residual potential with increasing layer weight is not observed with the present invention.
Coating with the photoconductive layer is carried out in the usual manner, using a solution which is applied, for example, by doctor blade or spray coating. The coating solution is preferably applied by means of a flow coater. Drying of the layer is carried out, for example, in drying channels.
For a dry-resist application, the recording material according to the present invention can be pro-duced in such a way that the photoconductive layer which is present on an intermediate support, for example, a polyethylene terephthalate film, is lami-nated under heat and pressure to the electrically con-ductive support. Due to the relatively low content of p-type conducting photoconductor, the recording material of the present invention can also be supplied in the Eorm of a support and a coating solution for application to the support as a liquid resist. It is then left to the user to effect coating according to a wipe-on process.
Layers of little thickness serve as the insu-lating barrier layers. For this purpose, polymers, 1:~5~ '7 such as W -curable or thermally curable systems, can be used that produce an improved adhesion of the photocon-ductive layer to the support material. The barrier layers can also comprise insulating metal oxide layers, for example, aluminum oxide layers, by which the sup-port surface is rendered hydrophilic. To ensure good electrophotographic properties, the layer weight of the insulating barrier layer should not exceed 4 g/m2.
As the electrically conductive supports, metals and also plastic materials metallized by vacuum metallization or lamination can be used. In addition, it is possible to use plastics provided with conductive coatings comprising polymeric binders and conductive materials, such as metal powders or graphite dust. In the production of electrophotographic printing plates, the pre~erred supports comprise aluminum sheets which have been roughened and anodically oxidized. For use as an electrophotographic resist, the preferred support is comprised of copper or has a copper surface, such as a copper-clad polyamide film.
As the customary additives, which can be pre-sent in the photoconductive layer in a quantity of up to 5 percent by weight, the layer contains substances which are added to the coating solution. Such additi-ves improve the surface texture and flexibility of thelayer and include, for example, plasticizers, such as triphenyl phosphate, and levelling agents, such as silicone oils.
The present invention is explained in detail by the following examples and comparative examples, which are intended to be illustrative only and in no sense limiting.
Example 1 An electrochemically pre-treated and anodi-cally oxidized aluminum web, of the type used as a sup-~25~5.~7 port for an oEfset-printing plate, was coated with the following dispersion to produce a dry layer weight of 6 g/m2: 15.0 9 of N,N'-dimethylperylene-3,4,9,10-tetra-carboxylic acid diimide (C.I. 71,130, formula II) were added to a solution of 10.0 g of a copolymer of vinyl acetate and crotonic acid (Mowilith Ct 5 ~ , manufac-tured by Hoechst AG) in 200 g of tetrahydrofura~ and were dispersed by milling in a ball mill for 2 hours.
The resulting mixture was thereafter admixed with 10 g of 2,5-bis-(4-diethylaminophenyl)-oxdiazole-1,3,4, 0.1 g of a silicone oil having a viscosity from 5 to 20, mPa.s, and with 65.0 g of the above-mentioned copolymer in 700 9 of tetrahydrofuran.
The layer obtained after drying was deep-red and had a matte appearance. The data obtained therefor are listed in the table below.
Example 2 15.0 g of Hostaperm Orange GR ~Pigment Orange 43, C.I. 71,105, formula I) were added to a solution of 10 9 of polybutyl methacrylate ( ~ Plexigum P 676, manufacturers Roehm GmbH) in 200 9 of tetrahydrofuran and were dispersed by milling in a ball mill for 2 hours. After adding 3 g of 2,5-bis-~4-diethylamino- -phenyl)-oxdiazole-1,3,4 and 32 9 of polymethyl methacrylate ~Plexigum M 345 ~,manufacturers Roehm GmbH) in 340 g of tetrahydrofuran, the layer was applied to a polyethylene terephthalate film, which had been vacuum metallized with aluminum to produce a layer weight of 6 g/m . The layer was then dried.
ExamPle 3 The procedure of Example 2 was ~ollowed, with the difference that the indicated oxdiazole was replaced by l,5-diphenyl-3~p-methoxyphenyl-pyrazoline, according to German Auslegeschrift No. 10 60 714 ~.2~S~7 (corresponding to U.S. Patent No. 3,180,729), and instead of polybutyl methasrylate and polymethyl methacrylate, a terpolymer of styrene, hexylmethacry-late and methacrylic acid in a molar ratio of 10 : 60 :
30 was used. The ]ayer was coated on a roughened and anodically oxidized aluminum support material to give a layer weight of about 6 g/m~.
After charging and imagewise exposing, the layer was treated with a dry developer. After fixing, the layer could be decoated without background via a commercially available decoating solution. The offset-printing plate thus obtained showed a high resolution and, when used in a printing test, yielded good printing qualities up to a print run of well over 100,000 copie~.
Example 4 The procedure of Example 3 was followed, with the difference that 4 methoxybenzaldehyde-diphenyl-hydrazone (German Offenlegungsschrift No. 32 46 036) was used instead of pyrazoline and, as the dye, N,N'-(3-methoxypropyl)-perylene-tetracarboxylic acid-
perylene tetracarboxylic acid diimides:
I? - ~ (II) ~,`.
~25~5~7 condensed quinones:
n~ ' ï (III) ~ (IV) in which R denotes a hydrogen, a phenyl radical or - an alkyl radical having frcm one to four carbon atoms, which may be substituted by halogen, an alkyl group or an alkoxy group, R' stands for halogen, such as chlorine or bromine, for the nitro group, the cyano ~ group, or an alkoxy group, and n is an integer between one and four.
In a number of publications, these pigments are referred to as being photoconductive. In this con-text, however, "photoconductivity~ is invariably understood as being based on interaction with other photoconductors. The color pigments thus play the role of a sensitizer which generates charge carriers in interaction with the p-type conducting photoconductor.
Accordingly, pigments are either used in very thin, charge-carrier generating layers or, in the case of homogeneous distribution, in a relatively low con-centration. According to U.S. Patents No. 3,879,200 lZ5~5~'7 and No. 3,904,407, good electrophotographic properties can only be achieved when these conditions are met.
But, to the contrary, it has now been found, in accordance with the present invention, that recording materials containing pigments represented by formulas I to IV in sufficiently high concentrations (which approximate those described for the phthalo-cyanines of German Offenlegungsschrift No. 14 97 205, mentioned above) are photoconductive even if a p-type conducting photoconductor has not been added to the layer. Widely varying behavior observed with positive and negative charging, respectively, indicates a pro-nounced n-type conductivity for these pigments. As in ZnO, good sensitivities can be achieved only with nega-tive charging.
Based on what was known previously of thepigments which are used according to the present inven-tion, it was unexpected to find a pronounced dependency of the electrophotographic properties of the layer on the binder employed. Thus, good sensitivities could only be obtained when binders were used which comprised a carbonyl group, for example, in the form of the car-boxyl group. Nitrocellulose, on the other hand, which normally is a binder having particularly favorable electrophotographic properties, proved to be extremely unfavorable in the photoconductive layer of the present invention; t:he same was true, for example, for polystyrene. The influence of the ~inder remains undi-minished even if, according to the present invention,30 p-type conducting photoconductors are added to the layer in the indicated quantities.
As in zinc oxide layers, a strong "trap"
effect, occurring in the initial phase of discharge, is observed in part of the photoconductive layers of the present invention, leading to an S-shaped discharge curve instead of the approximately exponential ~ 7 discharge characteristic normally obtained in org~nic photoconductor systems (see, for example, German Patent ~o. ~2 37 539). This S-shaped discharge characteristic yields particularly high voltage contrasts in the region of average exposure energies. As a consequence, the photoconductive layers of the present invention can be used for the production of charge images and toner images which have a particularly steep gradation and a particularly high resolution.
Utilization of the n-type conductivity of pigments employed according to the present invention requires a minimum pigment concentration of approxima-tely 10 percent by weight, based on the layer weight.
Pigment concentrations which are too high lead to a deterioration of charge acceptance and, consequently, a pigment content of about 50 percent by weight is regarded as an approximate upper limit. Pigment con-centrations between 15 and 30 percent by weight have proved to be particularly advantageous. These pigment concentrations, particularly concentrations in the upper end of the range, ensure decoatability of the photoconductive layer for application in making electrophotographically imageable printing plates and the like, if the alkali-soluble binders according to the present invention are employed.
When n-type conducting pigments are used in accordance with the present invention, an increase in sensitivity is obtained if minor amounts of p-type con-ducting photoconductors are added to the photoconductor30 layer. The p-type conducting photoconductor compounds that are customarily employed in electrophotographic layers are suitable in this regard. Examples of such compounds are oxdiazoles, oxazoles, aromatic amines, triphenyl methanes and hydrazones, and also polymeric compounds, such as polyvinyl-carbazole, as described, for example, in German Patents No. 10 58 836, No. 10 60 260~ No. 11 20 875, No. 11 97 325, No. 1~ 68 115t and No. 11 11 935.
In order to ensure good charge acceptance of the photoconductive layer, the concentration of the p-type conducting photoconductor should not e~ceed 20percent by weight, based on the layer weight.
Concentrations between 2 and 8 percent by weight have proved particularly favorableO
The p-type conductivity of the photoconductor contributes to charge-carrier generation and transport of positive charge carriers only in the upper region of the photoconductor layer. According to the present invention, the addition of p-type conducting photocon-ductor can therefore be limited to these upper zones,15 and the addition of p-type conducting photoconductor in the upper layer region has proved advantageous too,par-ticularly in the case o~ thicker layers. A systematic introduction of the p-type conducting photoconductor into the upper layer regions can be achieved either by a double layer arrangement or by post-treating the final layer, which does not yet contain the p-type con-ducting photoconductor, with corresponding solutions of the photoconductor, which are applied without binder.
By partially dissolving the binder and then diffusing the p-type conducting photoconductor into the upper region of the layer, photosensitivities are obtained that correspond to the photosensitivities of homoge-neously doped layers. Five percent strength solutions, for example, in tetrahydrofuran, have proved suitable for application.
Polymers with C-0-containing side groups, and also polycondensates and polyaddition compounds having C=O groups in the principal chain, are suitable as the electronically inert, carbonyl group-containing binders in the present invention~ Good photosensitivities are achieved USill9 homopolymers and copolymers of vinyl ` , -11-1259~,t7 esters, of acrylic acid esters and methacrylic acid esters, of acxylic acid and methacrylic acid, of vinyl ketones, of acrylic acid amides and methacrylic acid amides, and also using polyesters, polycarbonates, polyurethanes, ~olyamides and polyureas. Due to their mechanical properties, polyesters and polycarbonates ~re particularly suitable for use in flexible photocon-ductors.
For the production of printing plates, electronically inert, carbonyl group-containing binders are used in the present invention which are soluble or dispersible in aqueous-alkaline solutions. For this purpose, it is preferred to use copolymers of methacry-lic acid esters and methacrylic acid, optionally with15 additional monomers, such as acrylic acid and styrene.
These copolymers have proved superior to alkali-soluble ~inders based on acrylic acid and acrylic acid esters or on vinyl acetate and crotonic acid, respectively.
In particular, charge acceptance is higher in the pre-ferred copolymers, while photosensitivity is unchanged but these copolymers are also superior with regard to the criteria of fixability of the toner image obtained on the photoconductive layer, decoatability, and sub-sequent print run. Copolymers displaying a glass tran-sition temperature of ~ 40 C are particularly advantageous for the production of printing plates.
For use in an electrophotographic dry resist, only those binders are suitable that have a substan-tially lower glass transition temperature. Only when30 the glass transition temperature is substantially lower than 40 C can a complete transEer by lamination of the photoconductive layer be achieved. Binders which have proved particularly suitable include copolymers obtained from the monomers selected from acrylic acid, longer-chain acrylic acid esters and methacrylic acid esters, in combination (when appropriate) with addi-~2S95~7 tionaL monomers, such as methacrylic acid and styrene.
For an application in the form of a liquid resist, there are no limitations concerning the glass tran-sition temperature of the binder.
The thickness of the photoconductive layer depend~, in the first instance, on the intended use.
In order to ensure sufficient charge acceptance, the layer weight should not be below about 3 g/m~. For use as a liquid resist or for the production of electropho-tographic printing plates, the layer weight is appropriately between about 5 and 30 g/m2, for photo-conductor webs or drums in copiers between about 10 and 20 g/m2, and for a laminatable material between about 20 and 50 g/m2. A steep rise of the residual potential with increasing layer weight is not observed with the present invention.
Coating with the photoconductive layer is carried out in the usual manner, using a solution which is applied, for example, by doctor blade or spray coating. The coating solution is preferably applied by means of a flow coater. Drying of the layer is carried out, for example, in drying channels.
For a dry-resist application, the recording material according to the present invention can be pro-duced in such a way that the photoconductive layer which is present on an intermediate support, for example, a polyethylene terephthalate film, is lami-nated under heat and pressure to the electrically con-ductive support. Due to the relatively low content of p-type conducting photoconductor, the recording material of the present invention can also be supplied in the Eorm of a support and a coating solution for application to the support as a liquid resist. It is then left to the user to effect coating according to a wipe-on process.
Layers of little thickness serve as the insu-lating barrier layers. For this purpose, polymers, 1:~5~ '7 such as W -curable or thermally curable systems, can be used that produce an improved adhesion of the photocon-ductive layer to the support material. The barrier layers can also comprise insulating metal oxide layers, for example, aluminum oxide layers, by which the sup-port surface is rendered hydrophilic. To ensure good electrophotographic properties, the layer weight of the insulating barrier layer should not exceed 4 g/m2.
As the electrically conductive supports, metals and also plastic materials metallized by vacuum metallization or lamination can be used. In addition, it is possible to use plastics provided with conductive coatings comprising polymeric binders and conductive materials, such as metal powders or graphite dust. In the production of electrophotographic printing plates, the pre~erred supports comprise aluminum sheets which have been roughened and anodically oxidized. For use as an electrophotographic resist, the preferred support is comprised of copper or has a copper surface, such as a copper-clad polyamide film.
As the customary additives, which can be pre-sent in the photoconductive layer in a quantity of up to 5 percent by weight, the layer contains substances which are added to the coating solution. Such additi-ves improve the surface texture and flexibility of thelayer and include, for example, plasticizers, such as triphenyl phosphate, and levelling agents, such as silicone oils.
The present invention is explained in detail by the following examples and comparative examples, which are intended to be illustrative only and in no sense limiting.
Example 1 An electrochemically pre-treated and anodi-cally oxidized aluminum web, of the type used as a sup-~25~5.~7 port for an oEfset-printing plate, was coated with the following dispersion to produce a dry layer weight of 6 g/m2: 15.0 9 of N,N'-dimethylperylene-3,4,9,10-tetra-carboxylic acid diimide (C.I. 71,130, formula II) were added to a solution of 10.0 g of a copolymer of vinyl acetate and crotonic acid (Mowilith Ct 5 ~ , manufac-tured by Hoechst AG) in 200 g of tetrahydrofura~ and were dispersed by milling in a ball mill for 2 hours.
The resulting mixture was thereafter admixed with 10 g of 2,5-bis-(4-diethylaminophenyl)-oxdiazole-1,3,4, 0.1 g of a silicone oil having a viscosity from 5 to 20, mPa.s, and with 65.0 g of the above-mentioned copolymer in 700 9 of tetrahydrofuran.
The layer obtained after drying was deep-red and had a matte appearance. The data obtained therefor are listed in the table below.
Example 2 15.0 g of Hostaperm Orange GR ~Pigment Orange 43, C.I. 71,105, formula I) were added to a solution of 10 9 of polybutyl methacrylate ( ~ Plexigum P 676, manufacturers Roehm GmbH) in 200 9 of tetrahydrofuran and were dispersed by milling in a ball mill for 2 hours. After adding 3 g of 2,5-bis-~4-diethylamino- -phenyl)-oxdiazole-1,3,4 and 32 9 of polymethyl methacrylate ~Plexigum M 345 ~,manufacturers Roehm GmbH) in 340 g of tetrahydrofuran, the layer was applied to a polyethylene terephthalate film, which had been vacuum metallized with aluminum to produce a layer weight of 6 g/m . The layer was then dried.
ExamPle 3 The procedure of Example 2 was ~ollowed, with the difference that the indicated oxdiazole was replaced by l,5-diphenyl-3~p-methoxyphenyl-pyrazoline, according to German Auslegeschrift No. 10 60 714 ~.2~S~7 (corresponding to U.S. Patent No. 3,180,729), and instead of polybutyl methasrylate and polymethyl methacrylate, a terpolymer of styrene, hexylmethacry-late and methacrylic acid in a molar ratio of 10 : 60 :
30 was used. The ]ayer was coated on a roughened and anodically oxidized aluminum support material to give a layer weight of about 6 g/m~.
After charging and imagewise exposing, the layer was treated with a dry developer. After fixing, the layer could be decoated without background via a commercially available decoating solution. The offset-printing plate thus obtained showed a high resolution and, when used in a printing test, yielded good printing qualities up to a print run of well over 100,000 copie~.
Example 4 The procedure of Example 3 was followed, with the difference that 4 methoxybenzaldehyde-diphenyl-hydrazone (German Offenlegungsschrift No. 32 46 036) was used instead of pyrazoline and, as the dye, N,N'-(3-methoxypropyl)-perylene-tetracarboxylic acid-
3,4,9,10-diimicle (Paliogen-Black ~ , manufactured by BASF AG) was used instead of Hostaperm Orange GR.
Example 5 20.0 g of N,N'-dimethylperylene-3,4,9,10-tetra-carboxylic acid diimide (C.I. 71,130, formula II), as indicated in Example 1, were added to a solution of 20 g of a polycarbonate (Makrolon 2405 ~ , manufactured by Bayer AG) in 200 g of tetrahydrofuran and were dispersed in a ball mill for 2 hours. The dispersion was thereafter applied to a polyethylene terephthalate film which had been vacuum metallized with aluminum to give a dry layer weight of 6 g/m2.
1:25~5~.
Example 6 The procedure of Example 1 was followed, with the difference that the layer applied to the support had a layer weight of 20 gtm2-Although the layer weiyht had been increased by a factor of 3.3, a higher residual potential was not observed after exposure to white light at an energy of 30 /uJ~cm2 xamPle 7 1~
The procedure of Example 3 was followed, with the difference that a copper-clad polyimide film was used instead of the anodically oxidized aluminum sup-port. The contamination effects observed in photocon-ductor monolayers containing higher proportions of photoconductor, as disclosed, for example,by European patent applic:ation EP-A-O 137 217, ~hiCh lead to a con-siderable reduction of charge acceptance, were not - observed with the low concentrations of dissolved pho-toconductor used in this example. After t~e coated film thus obl:ained had been imaged and the toner image fixed, the film could be perfectly decoated in the areas not covered by the toner. By etching away the metal areas lying underneath, high-quality flexible circuit boards were obtained.
Example 8 As described in the preceding examples, a layer comprising 25% by weight of Hostaperm Orange GR
and 75% of the terpolymer of Example 3 was first applied to an anodically oxidized aluminum support to give a layer weight of 3 g/m2. This base layer was coated with a layer comprising 25% by weight of Hostaperm Orange GR, 20% by weight of 2,5-bis-(4-diethylaminophenyl)-oxdiazole-1,3,4 and 55% by lZ~9lX17 weight of the above-indicated terpolymer, providing a layer weight of 3 g/m2.
Example 9 According to Example 8, a precoating (base layer) having a layer weight of 6 g/m2 was applied to an anodically oxidiæed al~inum support~ The dried layer was then treated with a solution of 5% by weight of 2,5-bis-(4-diethylaminophenyl)-oxdiazole-1,3,4 in tetrahydrofuran and again dried. Corresponding results are obtained by treating the still moist precoating with an oxdiaæole solution ("wet-in-wet coating").
Example 10 The procedure of Example 2 was followed, with the difference that, instead of the methacrylates, a polyester (Dynapol L 206 ~ , manufactured by Dyn&mit Nobel AG) wa~, used. The material thus obtained had a high flexibility and the layer adhered well to the sup-port. Even when used in cyclically operating copiers, the electrophotographic properties of the material did not change with the number of char~ing and exposure cycles.
Example 11 The procedure of Example 2 was followed, with the difference that the terpolymer was replaced by a polyurethane (Desmolac 2100 OE~ , manufactured by Bayer AG).
Example 12 The procedure of Example 2 was followed, with the difference that polyvinylcarbaæole (Luvikan ~ , manufactured by BASF AG) was used as the photoconductor and N,N'-dimethylperylene-3,4,9,10-tetracarboxylic acid diimide as the pigment.
~ '7 Example 13 -The procedure of Example 2 was followed, with the difference that Hostaperm Scarlet G0 (C.I. 59,300, ~ormula IV~ was used as the pigment.
Example 14 The procedure of Example 2 was followed, with the difference that indanthrene golden-yellow-RK
(formula III, R=Br) was used as the pigment; the photo-conductor content amounted to 20% by weight.
Example 15 The procedure of Example 2 was followed, with the difference that a compound corresponding to formula I, R=N02, was used as the pigment; the photoconductor content amounted co 20% by weight.
Comparative Example 1 A solution comprised of (a) 50 9 of a copo-lymer of styrene and maleic anhydride, decomposition point 200 to 240 C, (b) 50 9 of 2,5-bis-(4-diethyl-aminophenyl)-oxdiazole-1,3,4 dissolved in 900 9 of tetrahydrofuran, with an addition of 0.1 9 of silicone oil, and (c) 0~5 9 of Rhodamine B (C.I. 45,170) dissolved in 5 9 of methanol was applied to a roughened and anodical:Ly oxidized aluminum support for printing plates. The resulting layer was then dried.
ComParative E,xample 2 The following dispersion was applied to a roughened and anodically oxidized aluminum support for printing plates, such tha~ a dry layer weight of 3 g/m2 resulted: 50 g of a copolymer of styrene and maleic anhydride were dissolved in 950 9 of tetrahydrofuran, .
, .
5~
with an addition of 0.1 g of silicone oil, and 2 g of N,N'-dimethylperylene-3,4,9,10-tetracarboxylic acid dii-mide (C.l. 71,130) were dispersed in the solution by milling in a ball mill for 2 hours. After drying, this charge carrier-generating layer was coated with a charge transport layer, also having dry layer weight of 3 g/m2, produced from the following solution: 50 g of a copolymer of styrene and maleic anhydride and 50 g of 2,5-bis-t4-diethylaminophenyl~oxdiazole-1,3,4 were dissolved in 700 g of tetrahydrofuran and 250 g of butyl acetate, with an addition of 0.1 9 of silicone oil.
omparative Example 3 A monolayer having a layer weight of 6 g/m2 was applied to a roughened and anodically oxidized alu-minum support for printing plates frGm the following dispersion: 6.25 g of Hostaperm Orange GR and 4.2 g of the terpolymer of Example 3 were dispersed and dissolved, respectively, in 50 g of tetrahydrofuran by milling for 2 hours in a ball mill, and were then added to a solution of 50 g of 2,5-bis-(4-die.hylaminophenyl)-oxdiazole-1,3,4, 40 g of the terpolymer of Example 3 and 0.1 9 of silicone oil in 850 g of tetrahydrofuran.
This example corresponds to a sensitive monolayer for-mulation described in U.S. Patent No. 3,879,200.
Comparative Example 4 The procedure oE Example 3 was ollowed, with the difference that the methacrylate terpolymer was replaced by a sulfonyl urethane which was also decoatable by means of aqueous-alkaline solutions (prepared according to German Offenlegungsschrift No. 32 10 577, Example 1).
~2S~5~'7 Come~ ive E~ 5 The procedure of Example 2 was followed, with the difference! that a cellulose nitrate having a degree of nitration of 12~2% was used instead of the methacry-lates.
Comparative Example 6 The procedure of Example 2 was followed, withthe difference that polystyrene was used instead of the methacrylates.
Comparative Example 7 The procedure of Example 3 was followed, with the difference that, instead of the trans-perinone Hostaperm Orange GR, the analogous cis-compound Permanent Red TG01 tC.I. 71,110), manufactured by Hoechst AG, was used.
The results of electrophotographic investiga-tions carried out on the layers prepared according to the above~described examples and comparative examples are compiled in the following table. In the table, El/2~ El/4~ cmd E1/8 refer to the exposure energies which must be applied, at a light intensity of 3 /uW/cm2, to obtain a discharge from -400 V to -200 V, -100 V, and -'i0 V, respectively.
-:
1:25~5~7 Table Exampl. max. charge E1/2 El/4 El/8 Ue(V) No. acceptance in ~J/cm2, halogen-after exposure (V) tungsten lamp, heat absorp- to 30 tion glass filter filtering ~J/cm2 out wavelengths beyond 700nm 1 -430 1.76 2.59 3.76 -11 2 -650 6.44 7.23 9.27 -15 3 -604 6.0 7.0 10.0 -31
Example 5 20.0 g of N,N'-dimethylperylene-3,4,9,10-tetra-carboxylic acid diimide (C.I. 71,130, formula II), as indicated in Example 1, were added to a solution of 20 g of a polycarbonate (Makrolon 2405 ~ , manufactured by Bayer AG) in 200 g of tetrahydrofuran and were dispersed in a ball mill for 2 hours. The dispersion was thereafter applied to a polyethylene terephthalate film which had been vacuum metallized with aluminum to give a dry layer weight of 6 g/m2.
1:25~5~.
Example 6 The procedure of Example 1 was followed, with the difference that the layer applied to the support had a layer weight of 20 gtm2-Although the layer weiyht had been increased by a factor of 3.3, a higher residual potential was not observed after exposure to white light at an energy of 30 /uJ~cm2 xamPle 7 1~
The procedure of Example 3 was followed, with the difference that a copper-clad polyimide film was used instead of the anodically oxidized aluminum sup-port. The contamination effects observed in photocon-ductor monolayers containing higher proportions of photoconductor, as disclosed, for example,by European patent applic:ation EP-A-O 137 217, ~hiCh lead to a con-siderable reduction of charge acceptance, were not - observed with the low concentrations of dissolved pho-toconductor used in this example. After t~e coated film thus obl:ained had been imaged and the toner image fixed, the film could be perfectly decoated in the areas not covered by the toner. By etching away the metal areas lying underneath, high-quality flexible circuit boards were obtained.
Example 8 As described in the preceding examples, a layer comprising 25% by weight of Hostaperm Orange GR
and 75% of the terpolymer of Example 3 was first applied to an anodically oxidized aluminum support to give a layer weight of 3 g/m2. This base layer was coated with a layer comprising 25% by weight of Hostaperm Orange GR, 20% by weight of 2,5-bis-(4-diethylaminophenyl)-oxdiazole-1,3,4 and 55% by lZ~9lX17 weight of the above-indicated terpolymer, providing a layer weight of 3 g/m2.
Example 9 According to Example 8, a precoating (base layer) having a layer weight of 6 g/m2 was applied to an anodically oxidiæed al~inum support~ The dried layer was then treated with a solution of 5% by weight of 2,5-bis-(4-diethylaminophenyl)-oxdiazole-1,3,4 in tetrahydrofuran and again dried. Corresponding results are obtained by treating the still moist precoating with an oxdiaæole solution ("wet-in-wet coating").
Example 10 The procedure of Example 2 was followed, with the difference that, instead of the methacrylates, a polyester (Dynapol L 206 ~ , manufactured by Dyn&mit Nobel AG) wa~, used. The material thus obtained had a high flexibility and the layer adhered well to the sup-port. Even when used in cyclically operating copiers, the electrophotographic properties of the material did not change with the number of char~ing and exposure cycles.
Example 11 The procedure of Example 2 was followed, with the difference that the terpolymer was replaced by a polyurethane (Desmolac 2100 OE~ , manufactured by Bayer AG).
Example 12 The procedure of Example 2 was followed, with the difference that polyvinylcarbaæole (Luvikan ~ , manufactured by BASF AG) was used as the photoconductor and N,N'-dimethylperylene-3,4,9,10-tetracarboxylic acid diimide as the pigment.
~ '7 Example 13 -The procedure of Example 2 was followed, with the difference that Hostaperm Scarlet G0 (C.I. 59,300, ~ormula IV~ was used as the pigment.
Example 14 The procedure of Example 2 was followed, with the difference that indanthrene golden-yellow-RK
(formula III, R=Br) was used as the pigment; the photo-conductor content amounted to 20% by weight.
Example 15 The procedure of Example 2 was followed, with the difference that a compound corresponding to formula I, R=N02, was used as the pigment; the photoconductor content amounted co 20% by weight.
Comparative Example 1 A solution comprised of (a) 50 9 of a copo-lymer of styrene and maleic anhydride, decomposition point 200 to 240 C, (b) 50 9 of 2,5-bis-(4-diethyl-aminophenyl)-oxdiazole-1,3,4 dissolved in 900 9 of tetrahydrofuran, with an addition of 0.1 9 of silicone oil, and (c) 0~5 9 of Rhodamine B (C.I. 45,170) dissolved in 5 9 of methanol was applied to a roughened and anodical:Ly oxidized aluminum support for printing plates. The resulting layer was then dried.
ComParative E,xample 2 The following dispersion was applied to a roughened and anodically oxidized aluminum support for printing plates, such tha~ a dry layer weight of 3 g/m2 resulted: 50 g of a copolymer of styrene and maleic anhydride were dissolved in 950 9 of tetrahydrofuran, .
, .
5~
with an addition of 0.1 g of silicone oil, and 2 g of N,N'-dimethylperylene-3,4,9,10-tetracarboxylic acid dii-mide (C.l. 71,130) were dispersed in the solution by milling in a ball mill for 2 hours. After drying, this charge carrier-generating layer was coated with a charge transport layer, also having dry layer weight of 3 g/m2, produced from the following solution: 50 g of a copolymer of styrene and maleic anhydride and 50 g of 2,5-bis-t4-diethylaminophenyl~oxdiazole-1,3,4 were dissolved in 700 g of tetrahydrofuran and 250 g of butyl acetate, with an addition of 0.1 9 of silicone oil.
omparative Example 3 A monolayer having a layer weight of 6 g/m2 was applied to a roughened and anodically oxidized alu-minum support for printing plates frGm the following dispersion: 6.25 g of Hostaperm Orange GR and 4.2 g of the terpolymer of Example 3 were dispersed and dissolved, respectively, in 50 g of tetrahydrofuran by milling for 2 hours in a ball mill, and were then added to a solution of 50 g of 2,5-bis-(4-die.hylaminophenyl)-oxdiazole-1,3,4, 40 g of the terpolymer of Example 3 and 0.1 9 of silicone oil in 850 g of tetrahydrofuran.
This example corresponds to a sensitive monolayer for-mulation described in U.S. Patent No. 3,879,200.
Comparative Example 4 The procedure oE Example 3 was ollowed, with the difference that the methacrylate terpolymer was replaced by a sulfonyl urethane which was also decoatable by means of aqueous-alkaline solutions (prepared according to German Offenlegungsschrift No. 32 10 577, Example 1).
~2S~5~'7 Come~ ive E~ 5 The procedure of Example 2 was followed, with the difference! that a cellulose nitrate having a degree of nitration of 12~2% was used instead of the methacry-lates.
Comparative Example 6 The procedure of Example 2 was followed, withthe difference that polystyrene was used instead of the methacrylates.
Comparative Example 7 The procedure of Example 3 was followed, with the difference that, instead of the trans-perinone Hostaperm Orange GR, the analogous cis-compound Permanent Red TG01 tC.I. 71,110), manufactured by Hoechst AG, was used.
The results of electrophotographic investiga-tions carried out on the layers prepared according to the above~described examples and comparative examples are compiled in the following table. In the table, El/2~ El/4~ cmd E1/8 refer to the exposure energies which must be applied, at a light intensity of 3 /uW/cm2, to obtain a discharge from -400 V to -200 V, -100 V, and -'i0 V, respectively.
-:
1:25~5~7 Table Exampl. max. charge E1/2 El/4 El/8 Ue(V) No. acceptance in ~J/cm2, halogen-after exposure (V) tungsten lamp, heat absorp- to 30 tion glass filter filtering ~J/cm2 out wavelengths beyond 700nm 1 -430 1.76 2.59 3.76 -11 2 -650 6.44 7.23 9.27 -15 3 -604 6.0 7.0 10.0 -31
4 -400 1.98 3.43 7.24 -19 -590 4.11 6.07 15.01 -31 6 -540 1.66 2.24 3~11 -11 7 -650 5.8 6.7 9.2 -25 8 -600 6.48 7.10 8.06 -15 9 -650 5.11 6.00 6.90 - 7 -500 4.44 5.60 7.28 - 7 11 -600 5.0 6.~ 7.6 -11 12 -460 4.63 9.54 20.3 -27 13 -600 7.7 11 20 -11 14 -220 1.22 2.03 4.16 -11 ~, -180 5.8 7 9 0 Cl -800 9.3 20 45 -80 C~ -650 4.5 11.7 24.7 -40 C3 -660 9.4 13.4 18.4 -35 C4 -520 17.9 44 85 -150 C7 -530 24.~ 102 - -180 comm. -440 3.06 3.63 4.26 0 ZnO-printing plate 3 +440 +160
Claims (17)
1. An electrophotographic recording material comprising an electrically conductive support and a photoconductive layer, wherein said photoconductive layer comprises (a) at least one organic n-type con-ducting pigment in a concentration between about 10 and 50 percent by weight, relative to the layer weight of said photoconductive layer, (b) at least one electroni-cally inert carbonyl group-containing binder, and (c) an organic p-type conducting photoconductor in a con-centration from about 0 to 20 percent by weight, rela-tive to the layer weight of said photoconductive layer.
2. A recording material as claimed in Claim 1, wherein said n-type conducting pigment is present in a concentration between about 15 and 30 percent by weight and said p-type conducting photoconductor is present in a concentration from about 2 to 8 percent by weight, relative to said layer weight.
3. A recording material as claimed in Claim 1, wherein said n-type conducting pigment comprises a compound selected from the group consisting of a trans-perinone, a perylene-tetracarboxylic acid diimide and a condensed quinone.
4. A recording material as claimed in Claim 1, wherein said n-type conducting pigment comprises Hostaperm Orange GR (C.I. 71,105).
5. A recording material as claimed in Claim 1, wherein said n-type conducting pigment comprises N,N'-dimethylperylene-3,4,9,10-tetracarboxylic acid dii-mide (C.I. 71,130).
6. A recording material as claimed in Claim 1, wherein said n-type conducting pigment comprises N,N'-bis-(methoxypropyl)-perylene-3,4,9,10-tetracarbox-ylic acid diimide.
7. A recording material as claimed in Claim 1, wherein said carbonyl group-containing binder is soluble or dispersible in an aqueous alkaline solution.
8. A recording material as claimed in Claim 7, wherein said carbonyl group-containing binder comprises a copolymer comprised of a methacrylic acid ester and methacrylic acid.
9. A recording material as claimed in Claim 8, wherein said copolymer further comprises a monomer from the group consisting of acrylic acid and styrene.
10. A recording material as claimed in Claim 8, wherein said carbonyl group-containing binder has a glass transition temperature above about 40° C.
11. A recording material as claimed in Claim 1, wherein said support comprises aluminum.
12. A recording material as claimed in Claim 2, wherein said support comprises aluminum.
13. A recording material as claimed in Claim 1, wherein said support is comprised of copper or has a copper surface.
14. A recording material as claimed in Claim 1, wherein said photoconductive layer was transferred from an intermediate support to the electrically con-ductive support by lamination under heat and pressure.
15. A recording material as claimed in Claim 1, wherein said photoconductive layer comprises (1) a base layer comprised of an organic n-type conducting pigment and an electronically inert binder and (2) a covering layer provided on said base layer and comprising an organic n-type conducting pigment, an electronically inert binder, and an organic p-type con-ducting photoconductor.
16. A recording material as claimed in Claim 15, wherein said base layer and said covering layer, respectively, have layer weights in a ratio ranging between about 10 : 1 and 1 : 10.
17. A recording material as claimed in Claim 1, further comprising an insulating barrier layer be-tween said support and said photoconductive layer.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP3417951.8 | 1984-05-15 | ||
| DE19843417951 DE3417951A1 (en) | 1984-05-15 | 1984-05-15 | ELECTROPHOTOGRAPHIC RECORDING MATERIAL |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1259517A true CA1259517A (en) | 1989-09-19 |
Family
ID=6235859
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000481002A Expired CA1259517A (en) | 1984-05-15 | 1985-05-08 | Electrophotographic recording material |
Country Status (11)
| Country | Link |
|---|---|
| US (1) | US4668600A (en) |
| EP (1) | EP0161648B2 (en) |
| JP (1) | JPS60254142A (en) |
| AT (1) | ATE29603T1 (en) |
| AU (1) | AU574626B2 (en) |
| BR (1) | BR8502270A (en) |
| CA (1) | CA1259517A (en) |
| DE (2) | DE3417951A1 (en) |
| ES (1) | ES8607576A1 (en) |
| FI (1) | FI851884L (en) |
| ZA (1) | ZA853586B (en) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3532346A1 (en) * | 1985-09-11 | 1987-03-12 | Hoechst Ag | METHOD FOR PRODUCING PRINTING FORMS |
| JP2729616B2 (en) * | 1986-10-17 | 1998-03-18 | 富士ゼロックス株式会社 | Electrophotographic photoreceptor |
| US4999272A (en) * | 1988-08-31 | 1991-03-12 | Canon Kabushiki Kaisha | Electrophotographic analog and digital imaging and developing using magnetic toner |
| US5145759A (en) * | 1989-04-21 | 1992-09-08 | Agfa-Gevaert, N.V. | Electrophotographic recording material |
| US5273853A (en) * | 1989-06-13 | 1993-12-28 | Mita Industrial Co., Ltd. | Black photoconductive toner having sensitivity to light in the wavelength range of semiconductor lasers |
| JPH03146957A (en) * | 1989-11-02 | 1991-06-21 | Iwatsu Electric Co Ltd | Printing plate for electrophotographic engraving |
| JP2717584B2 (en) * | 1989-11-17 | 1998-02-18 | 富士写真フイルム株式会社 | Printing plate for electrophotographic plate making |
| US5069992A (en) * | 1989-11-17 | 1991-12-03 | Fuji Photo Film Co., Ltd. | Electrophotographic printing plate precursor containing alkali-soluble polyurethane resin as binder resin |
| ES2082816T3 (en) * | 1989-11-30 | 1996-04-01 | Mita Industrial Co Ltd | PHOTOSENSITIVE ELECTROPHOTOGRAPHIC ELEMENT. |
| US5225307A (en) * | 1992-01-31 | 1993-07-06 | Xerox Corporation | Processes for the preparation of photogenerating compositions |
| JP2944296B2 (en) | 1992-04-06 | 1999-08-30 | 富士写真フイルム株式会社 | Manufacturing method of photosensitive lithographic printing plate |
| US5266429A (en) * | 1992-12-21 | 1993-11-30 | Eastman Kodak Company | Polyester-imides in electrophotographic elements |
| US5900342A (en) * | 1996-04-26 | 1999-05-04 | Eastman Kodak Company | Photoconductive element having an outermost layer of a fluorinated diamond-like carbon and method of making the same |
| US6294301B1 (en) * | 2000-05-19 | 2001-09-25 | Nexpress Solutions Llc | Polymer and photoconductive element having a polymeric barrier layer |
| US6593046B2 (en) | 2000-05-19 | 2003-07-15 | Heidelberger Druckmaschinen Ag | Photoconductive elements having a polymeric barrier layer |
| US6866977B2 (en) | 2000-05-19 | 2005-03-15 | Eastman Kodak Company | Photoconductive elements having a polymeric barrier layer |
| US6194110B1 (en) * | 2000-07-13 | 2001-02-27 | Xerox Corporation | Imaging members |
| US7270927B2 (en) * | 2004-11-15 | 2007-09-18 | Xerox Corporation | Non-halogenated polymeric binder |
Family Cites Families (31)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL217825A (en) * | 1956-06-04 | |||
| BE558630A (en) * | 1956-06-27 | |||
| US3180729A (en) * | 1956-12-22 | 1965-04-27 | Azoplate Corp | Material for electrophotographic reproduction |
| US3121006A (en) * | 1957-06-26 | 1964-02-11 | Xerox Corp | Photo-active member for xerography |
| BE570790A (en) * | 1957-09-07 | |||
| NL126440C (en) * | 1958-08-20 | |||
| DE1117391B (en) * | 1959-03-18 | 1961-11-16 | Kalle Ag | Electrophotographic process for the production of printing forms |
| NL269304A (en) * | 1960-09-17 | |||
| US3238150A (en) * | 1962-09-12 | 1966-03-01 | Xerox Corp | Photoconductive cadmium sulfide powder and method for the preparation thereof |
| JPS494338B1 (en) * | 1964-06-15 | 1974-01-31 | ||
| US3816118A (en) * | 1964-06-15 | 1974-06-11 | Xerox Corp | Electrophotographic element containing phthalocyanine |
| US3877935A (en) * | 1970-12-01 | 1975-04-15 | Xerox Corp | Novel xerographic plate containing photoinjecting polynuclear quinone pigments |
| US3904407A (en) * | 1970-12-01 | 1975-09-09 | Xerox Corp | Xerographic plate containing photoinjecting perylene pigments |
| US3870516A (en) * | 1970-12-01 | 1975-03-11 | Xerox Corp | Method of imaging photoconductor in change transport binder |
| US3879200A (en) * | 1970-12-01 | 1975-04-22 | Xerox Corp | Novel xerographic plate containing photoinjecting bis-benzimidazole pigments |
| DE2237539C3 (en) * | 1972-07-31 | 1981-05-21 | Hoechst Ag, 6000 Frankfurt | Electrophotographic recording material |
| DE2239923C3 (en) * | 1972-08-14 | 1981-08-13 | Hoechst Ag, 6000 Frankfurt | Electrophotographic recording material |
| NL180460C (en) * | 1972-04-26 | 1987-02-16 | Hoechst Ag | ELECTROPHOTOGRAPHIC REGISTRATION EQUIPMENT. |
| US4315981A (en) * | 1972-07-31 | 1982-02-16 | Hoechst Aktiengesellschaft | Organic double layer electrophotographic recording material |
| JPS5724388B2 (en) * | 1972-11-27 | 1982-05-24 | ||
| JPS521667B2 (en) * | 1973-08-08 | 1977-01-17 | ||
| AU507694B2 (en) * | 1975-06-14 | 1980-02-21 | Hoechst Aktiengesellschaft | Electrophotographic reproduction |
| JPS54150128A (en) * | 1978-05-17 | 1979-11-26 | Mitsubishi Chem Ind | Electrophotographic photosensitive member |
| JPS6035057B2 (en) * | 1979-07-13 | 1985-08-12 | 株式会社リコー | Electrophotographic photoreceptor |
| DE3019326C2 (en) * | 1980-05-21 | 1983-03-03 | Hoechst Ag, 6000 Frankfurt | Electrophotographic recording material |
| DE3110960A1 (en) * | 1981-03-20 | 1982-09-30 | Basf Ag, 6700 Ludwigshafen | ELECTROPHOTOGRAPHIC RECORDING MATERIAL |
| US4418134A (en) * | 1981-08-03 | 1983-11-29 | Polychrome Corporation | Aqueous composition-sensitive photoconductive composition |
| ZA825152B (en) * | 1981-08-03 | 1983-07-27 | Polychrome Corp | Aqueous composition-sensitive photoconductive composition |
| DE3210577A1 (en) * | 1982-03-23 | 1983-10-06 | Hoechst Ag | ELECTROPHOTOGRAPHIC RECORDING MATERIAL |
| EP0096989A3 (en) * | 1982-05-26 | 1984-11-14 | Toray Industries, Inc. | Electrophotographic photosensitive material |
| DE3329442A1 (en) * | 1983-08-16 | 1985-03-21 | Hoechst Ag, 6230 Frankfurt | ELECTROPHOTOGRAPHIC RECORDING MATERIAL AND METHOD FOR THE PRODUCTION THEREOF |
-
1984
- 1984-05-15 DE DE19843417951 patent/DE3417951A1/en not_active Withdrawn
-
1985
- 1985-05-08 CA CA000481002A patent/CA1259517A/en not_active Expired
- 1985-05-10 ES ES543034A patent/ES8607576A1/en not_active Expired
- 1985-05-10 DE DE8585105785T patent/DE3560608D1/en not_active Expired
- 1985-05-10 US US06/732,702 patent/US4668600A/en not_active Expired - Fee Related
- 1985-05-10 AT AT85105785T patent/ATE29603T1/en not_active IP Right Cessation
- 1985-05-10 EP EP85105785A patent/EP0161648B2/en not_active Expired - Lifetime
- 1985-05-13 ZA ZA853586A patent/ZA853586B/en unknown
- 1985-05-13 FI FI851884A patent/FI851884L/en not_active Application Discontinuation
- 1985-05-14 BR BR8502270A patent/BR8502270A/en not_active IP Right Cessation
- 1985-05-15 AU AU42513/85A patent/AU574626B2/en not_active Ceased
- 1985-05-15 JP JP60101665A patent/JPS60254142A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| ES543034A0 (en) | 1986-06-01 |
| FI851884L (en) | 1985-11-16 |
| EP0161648B1 (en) | 1987-09-09 |
| ES8607576A1 (en) | 1986-06-01 |
| US4668600A (en) | 1987-05-26 |
| AU4251385A (en) | 1985-11-21 |
| JPS60254142A (en) | 1985-12-14 |
| ATE29603T1 (en) | 1987-09-15 |
| DE3560608D1 (en) | 1987-10-15 |
| DE3417951A1 (en) | 1985-11-21 |
| ZA853586B (en) | 1985-12-24 |
| FI851884A0 (en) | 1985-05-13 |
| EP0161648A1 (en) | 1985-11-21 |
| AU574626B2 (en) | 1988-07-07 |
| BR8502270A (en) | 1986-01-14 |
| EP0161648B2 (en) | 1993-11-03 |
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