CA1146794A - Electrophotographic reproduction material including an oxazole photoconductor and a combination of cyanine and xanthene sensitizing dyes - Google Patents
Electrophotographic reproduction material including an oxazole photoconductor and a combination of cyanine and xanthene sensitizing dyesInfo
- Publication number
- CA1146794A CA1146794A CA000366136A CA366136A CA1146794A CA 1146794 A CA1146794 A CA 1146794A CA 000366136 A CA000366136 A CA 000366136A CA 366136 A CA366136 A CA 366136A CA 1146794 A CA1146794 A CA 1146794A
- Authority
- CA
- Canada
- Prior art keywords
- recording material
- photoconductor
- photoconductive layer
- group
- radical
- 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
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
- C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
- C09C1/44—Carbon
- C09C1/48—Carbon black
- C09C1/487—Separation; Recovery
-
- 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
- G03G5/0624—Heterocyclic compounds containing one hetero ring
- G03G5/0627—Heterocyclic compounds containing one hetero ring being five-membered
- G03G5/0631—Heterocyclic compounds containing one hetero ring being five-membered containing two hetero atoms
-
- 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
- G03G5/0624—Heterocyclic compounds containing one hetero ring
- G03G5/0627—Heterocyclic compounds containing one hetero ring being five-membered
- G03G5/0633—Heterocyclic compounds containing one hetero ring being five-membered containing three hetero atoms
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/12—Surface area
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/24—Treatment of water, waste water, or sewage by flotation
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/26—Treatment of water, waste water, or sewage by extraction
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/30—Organic compounds
- C02F2101/32—Hydrocarbons, e.g. oil
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/18—Nature of the water, waste water, sewage or sludge to be treated from the purification of gaseous effluents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/02—Temperature
Abstract
ABSTRACT OF THE DISCLOSURE
An electrophotographic recording material is disclosed including an electrically conductive support, and a photoconductive layer comprising an organic photo-conductor, a binder, a sensitizing dyestuff and con-ventional additives. The recording material can be imaged with an argon ion laser and has a sensitivity in the blue spectral region to prevent blue lines and markings used on paste-up register sheets from appearing on the electrophotographic printing plate during copying in a reprocamera. Additionally, the sensitivity in the yellow spectral region prevents yellowed originals from being produced with background. Finally, the material is in-sensitive in the red spectral region so that it can be handled in the red light of a darkroom.
An electrophotographic recording material is disclosed including an electrically conductive support, and a photoconductive layer comprising an organic photo-conductor, a binder, a sensitizing dyestuff and con-ventional additives. The recording material can be imaged with an argon ion laser and has a sensitivity in the blue spectral region to prevent blue lines and markings used on paste-up register sheets from appearing on the electrophotographic printing plate during copying in a reprocamera. Additionally, the sensitivity in the yellow spectral region prevents yellowed originals from being produced with background. Finally, the material is in-sensitive in the red spectral region so that it can be handled in the red light of a darkroom.
Description
ELECIROPHOIY)GRAPHIC REPRODUCTICN M~BPIAI, . _ _ _ _ BACKGROUND OF THE INUENTION
me present invention relates to a recording material for electro-photographic reproduction including an electrically conductive support suitable for the manufacture of printing forms or printed circuits, and a photoconductive layer oomprising an organic photoconductor, a binder, a sensitizing dyestuff and conventional additives, and more particularly to such recording material respon-sive to different wavelengths of light.
German Patent No. 2,5261720, discloses an electrophotographic reaord-ing material for the manufacture of printing forms or printed circuits, which includes a photoconducti~e layer aontaining a binder and a sensitizing cyanine - dyestuff having an absorption maximum ketween 400 and 550 nm arranged on a suit-able support. This material is especially suited for exposure with an argon ion laser at a wavelength of 488 nm. Additionally, this material is adapted to pre-vent the blue orientation lines and markings used on paste-up register sheets for newspaper printing frcm appearing on the electrophotographic printing plate d~ring aopying in a reprocamera. Sin oe the sensitivity of the material de-creases steeply at wavelengths greater than 500 nm, the sensitivity in the yellcw spectral region is such that yellowed originals tend to be reproduced in the camera with background. This results in a pho~ographic printing plate hav-ing an undesirable quality when preparing a page make-up incorporating older and already yellcwed text or picture elements.
A further drawback associated with this material is that the light emitted by the light sources of the reprocamera is o~ly partially u æ d for pro-~ucing an image d~ring the exposure of the known material, resulting in rela-tively long exposure times.
Additionally, electrophotographic materials for the manufacture of 7~
printing forms and printed circuits should be insensitive in the red spectral region so that they can be handled under a red darkrocm light. It is also known from German Offenlegungsschrift No. 2,817,428, to use a panchromatically sensi-tive recording material for the manufacture of printing forms and printed cir-cuits by an electrophotographic process. me material contains a mixture of a polymethine dyestuff and a triaryl~ethane dyestuff as the sensitizer in the photoconductive layer. Such a material, however, must be handled in the dark, and this leads to difficulties in practioe.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an electrophotographic material adapted to be imaged using ~W argon ion lasers and having a sensitivity in the blue spectral region to prevent the reproduction of blue lines and markings from apFearing on the electrophotographic printing plate during copying in the reprocamera.
It is a further object of the present invention to provide an electro-photographic material having a sensitivity in the yellow spectral region so that yellcwed originals are reproduced by a reprocamera without backgrcund and which efficiently utilizes the light energy m~de available by the reprocameras to pro-vide short exposure times.
It is a further object of the present invention 7~
to provide an electrophotographic material ~hich is in-sensitive ln the red spectral region so that it can be handled under a red darkroom light.
In accomplishing the foregoing objects, there has been provided in accordance with the present invention an electrophotographic recording material comprising an electrically eonductive sup~ort and a photoconductive layer including an organic photoconductor, a binder, a ~ p~'~C~I CL il V
sensitizing-dyestuff andJ~conve~ional additives. The photoconductor is represented by a compound of the general Eormula R2 X~ N R
~_lc\ /c ~
wherein Rl denotes hydrogen, an alkyl group, an alkoxy group, both having between 1 and 4 carbon atoms, a halogen, or a dialkylamino group having between 1 and 4 carbon atoms, R2 denotes a dialkylamino group having between 1 and 4 carbon atoms, and X denotes nitrogen or a -CR3 group wherein R3 is a phenyl optionally substituted by a halogen, a monoalkylamino group, a dialkylamino group, or an alkyl group having between 1 and 4 carbon atoms.
The binder comprises alkali-soluble binders, and the sensitizing dyestuff comprises a cyanine dyestuff ab-sorbing between 400 and ~ nm and an aminoxanthene dyestuff absorbing between 450 and 600 nm. The surface of the elec~ric-ally conductive support may be mechanically or electro-chemically roughened as well as anodized and treated with polyvinylphosphonic acid. Addditionally, the surface can be improved by silicatization- Such conventional additives as levelling agents, plasticizers, as well as adhesion-promoters can be included in -the photoconductive layer.
~67~4c Further objects, features and advantages of the present invention will kecc~e apparent from the detailed description of preferred embodiments which follows.
~ETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
.
A recording material is disclosed comprising a photoconductor which represents a compound of -the general formula ~ C ~
in which Rl denotes hydrogen, aIkyl, alkoxy having 1 - 4 carbon atoms, halogen or diaIkylamino having 1 - 4 carbon atoms, R2 denotes dialkylamino having 1 - 4 carbon atoms and X denotes nitrogen or -CR3 with R3 being phenyl which is optionally substituted by halogen, alkylamino or diaIkylamino groups or alkyl having 1 - 4 carbon atoms, a binder which is selected from the group ccmprising alkali-soluble binders, and a sensitizing dyestuff which comprises a cyanine dyestuff absorbing between 400 and 550 nm and an aminoxanthene dyestuff absorb ing be~ween 450 and 600 nm.
The photoconductor used in -the combination is conventional.
Oxadiazole derivatives are used, such as have been disclosed in German Patent No. 1,058,836, and especially 2,5-bis-(4'-diethylaminophenyl)-oxadiazole should be singled out as being particularly suitable. Triphenyloxazole derivatives, which are descriked in German Patent No. 1,120,875, can also be used according to the invention. Among the latter, 2-phenyl-4-(2'-chlorophe~yl)-5-(4"-diethyl-aminophenyl)-oxazole and 2,4-bis-(2'-chlorophenyl)-5-(4"-diethylaminophenyl)-oxazole are mention2d as being preferably 7~
suitable because of their superior electrophotographic properties.
Alkali-soluble binders of the present invention are high-molecular substances which carry groups con-ferring solubility in alkaline aqueous or alcoholicsolvent systems. Examples of such groups are acid, anhydride, carboxyl, phenol, sulfonic acid, sulfonamide or sulfonimîde groups. Binders having high acid numbers, especially of more than 100, are preferably em~loyed since these are particularly readily soluble in alkaline aqueous-alcoholic solvent systems. Copolymers of styrene and maleic anhydride, and ter~olymers o~ styrene, methacrylic acid and methacrylate are very particularly suitable.
Copolymers of methacrylic acid and methacrylate are also highly suitable.
~xamples of cyanine dyestuffs which are suitable according to the invention and which absorb in the wave-length region from 400 to 550 nm, include, for example, Astrazongelb 3G (C.I. 48,055), Astrazongelb 5G (C.I. 48,065) 20 or Basic Yellow 52,115 (C.I. 48,060). Also, suitable dyestuffs which have not yet been classified include Astrazonorange 3R, Astrazongelb 7GLL, Astrazongelb GRL
and Astragelb R. Further, Astrozonorange R (C.I. 48,040) and Astrazonorange G (C.I. 48,035) have proved particu-larly suitable. The proportion of cyanine dyestuffs, re-lative to the photoconductorj is preferably 0.001 to 0.1 part by weight.
Among the aminoxanthene dyestuffs absorbing between 450 and 600 nm, the Rhodamines are very suitable, - 30 particularlyRhodamineB andRhodamineFB (C.I. 45,170).
Their proportion, relative to the photoconductor, is pre-ferably 0.001 to 0.01 part by weight.
`~ The combination according to the invention is applied to supports, such as are conventionally used for the manufacture of printing forms for letterpress printing, planographic printing, gravure printing and for printed circuits. Suitable materials include aluminum, zinc, ., 7~
magnesium, copper or multi-metal plates. In particul æ cases, spe dal pa~ers or plastic films with vapor-deposited metal can also be used. Aluminum foils hav-ing improved surfaoe s have proved particularly suitable for planographic print-ing.
me surface of the ~support can be improved by mechanical or electro-chemical roughening and, in the case of aluminum, if appropriate, by subsequent anodizing and treatment with polyvinylphosphonic acid according to German Offenlegungsschrift No. 1,621,478, Other known processes for surfa oe improve-ment can be used for the preparation of a suitable support, for example, by silicatization. me surface improv~m~nt allows a longer print run and reduoe s the sensitivity to oxidation.
As conventional additives in the photoconductive layer, the recording material according to the invention can contain levelling agents, plasticizers and adhesion-prcmoters as well as a combination of those additives.
me present invention provides a recording material having outstanding properties. It is distinguished by a high light-sensitivity providing an e~po-sure time in the reprocamera which can be redu oe d to half of what is currently exeerienoe d with ccmmercially available materials. Discharge in the dæk is so slight that upon exposure the latent ch æge image produced has a high ch æ ge con-trast. After applying toner, an image can be reproduoe d with very sharp edgesand good resolution. Due to the high ch æge contrast, even fine screen dots in light tone-value ranges can be satisfactorily reproduced. l~oreover, discharge of the layers in the light leads to very low residual voltages so that images obtained after toner has been applied æe distinguished by superior freedom from background in the non-image areas. me spectral sensitivity falls steeply at 600 nm so that the layers can be handled under red light, without the occurren oe of image losses.
The printing forms manufactured using the photoconductive layers according to the invention are distinguished by a high stability during the printing run.
If suitable support materials are used, the lenqth of the printing run can be more than 100,000. If the photo-conductive layers are used for the manufacture of printedcircuits, excellent resistance to commercially available etches is ~ound.
The invention is explained in more detail by reference to the examples below.
The solution, described in Example 3 of German Patent No. 2,526,720,of 4S g of 2-vinyl-4-(2'-chloro-phenyl)-5-(4"-diethylaminophenyl)-oxazole, 45 g of a co-polymer of styrene and maleic anhydride, 2.25 g of Astrazonorange R in 280 g of tetrahydrofuran, 180 g of methylglycol and 84 g of butyl acetate is applied to a 300 ~m thick aluminum foil which has been electro-chemically roughened, anodized and treated with poly-vinylphosphonic acid. After the evaporation of the solvents,an approximately 5 ~m thick photoconductor layer remains. The layer is charged to -450 V using a coronoa and exposed for 26 seconds in a reprocamera having 10 halogen lamps of 600 Watts each. The original used is a paste-up of a newspaper page on a register sheet having blue orientation lines. The make-up contains, inter alia, a text on yellowed paper. A~ter applying toner to the latent charge image generated by the ex-posure, the blue orientation lines of the register sheet do not appear on the electrophotographic copy, but the text on the yellowed paper is reproduced with back-ground.
~ ccording to the invention, 40 g of 2-phenyl-4-(2'-chlorophenyl)-5~(4"-diethylaminophenyl)-oxazole and 60 g of a copolymer of styrene and maleic anhydride are dissolved in a solvent mixture consisting of 400 g of tetrahydrofuran, 200 g of methylglycol and 100 g of butyl acetate. 30 g of methanolic solution of 2 g of ~467~
Astrazonorange R (C.I. 48,040) and 0.2 g of Rhodamin B (C.I. 45,170) are also added to the solution. This resulting solution is used for coating the same support material so that after evaporation of the solvents, a photoconductor layer of 5 ~m thickness is obtained. After charging the layer to -450 V, the layer is exposed in the same reprocamera with the same light souroe s, and using the same original. Although the layer of the present example contains only 40%
of photoconductor instead of 50~ as described in Example 3 of German Patent No.
me present invention relates to a recording material for electro-photographic reproduction including an electrically conductive support suitable for the manufacture of printing forms or printed circuits, and a photoconductive layer oomprising an organic photoconductor, a binder, a sensitizing dyestuff and conventional additives, and more particularly to such recording material respon-sive to different wavelengths of light.
German Patent No. 2,5261720, discloses an electrophotographic reaord-ing material for the manufacture of printing forms or printed circuits, which includes a photoconducti~e layer aontaining a binder and a sensitizing cyanine - dyestuff having an absorption maximum ketween 400 and 550 nm arranged on a suit-able support. This material is especially suited for exposure with an argon ion laser at a wavelength of 488 nm. Additionally, this material is adapted to pre-vent the blue orientation lines and markings used on paste-up register sheets for newspaper printing frcm appearing on the electrophotographic printing plate d~ring aopying in a reprocamera. Sin oe the sensitivity of the material de-creases steeply at wavelengths greater than 500 nm, the sensitivity in the yellcw spectral region is such that yellowed originals tend to be reproduced in the camera with background. This results in a pho~ographic printing plate hav-ing an undesirable quality when preparing a page make-up incorporating older and already yellcwed text or picture elements.
A further drawback associated with this material is that the light emitted by the light sources of the reprocamera is o~ly partially u æ d for pro-~ucing an image d~ring the exposure of the known material, resulting in rela-tively long exposure times.
Additionally, electrophotographic materials for the manufacture of 7~
printing forms and printed circuits should be insensitive in the red spectral region so that they can be handled under a red darkrocm light. It is also known from German Offenlegungsschrift No. 2,817,428, to use a panchromatically sensi-tive recording material for the manufacture of printing forms and printed cir-cuits by an electrophotographic process. me material contains a mixture of a polymethine dyestuff and a triaryl~ethane dyestuff as the sensitizer in the photoconductive layer. Such a material, however, must be handled in the dark, and this leads to difficulties in practioe.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an electrophotographic material adapted to be imaged using ~W argon ion lasers and having a sensitivity in the blue spectral region to prevent the reproduction of blue lines and markings from apFearing on the electrophotographic printing plate during copying in the reprocamera.
It is a further object of the present invention to provide an electro-photographic material having a sensitivity in the yellow spectral region so that yellcwed originals are reproduced by a reprocamera without backgrcund and which efficiently utilizes the light energy m~de available by the reprocameras to pro-vide short exposure times.
It is a further object of the present invention 7~
to provide an electrophotographic material ~hich is in-sensitive ln the red spectral region so that it can be handled under a red darkroom light.
In accomplishing the foregoing objects, there has been provided in accordance with the present invention an electrophotographic recording material comprising an electrically eonductive sup~ort and a photoconductive layer including an organic photoconductor, a binder, a ~ p~'~C~I CL il V
sensitizing-dyestuff andJ~conve~ional additives. The photoconductor is represented by a compound of the general Eormula R2 X~ N R
~_lc\ /c ~
wherein Rl denotes hydrogen, an alkyl group, an alkoxy group, both having between 1 and 4 carbon atoms, a halogen, or a dialkylamino group having between 1 and 4 carbon atoms, R2 denotes a dialkylamino group having between 1 and 4 carbon atoms, and X denotes nitrogen or a -CR3 group wherein R3 is a phenyl optionally substituted by a halogen, a monoalkylamino group, a dialkylamino group, or an alkyl group having between 1 and 4 carbon atoms.
The binder comprises alkali-soluble binders, and the sensitizing dyestuff comprises a cyanine dyestuff ab-sorbing between 400 and ~ nm and an aminoxanthene dyestuff absorbing between 450 and 600 nm. The surface of the elec~ric-ally conductive support may be mechanically or electro-chemically roughened as well as anodized and treated with polyvinylphosphonic acid. Addditionally, the surface can be improved by silicatization- Such conventional additives as levelling agents, plasticizers, as well as adhesion-promoters can be included in -the photoconductive layer.
~67~4c Further objects, features and advantages of the present invention will kecc~e apparent from the detailed description of preferred embodiments which follows.
~ETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
.
A recording material is disclosed comprising a photoconductor which represents a compound of -the general formula ~ C ~
in which Rl denotes hydrogen, aIkyl, alkoxy having 1 - 4 carbon atoms, halogen or diaIkylamino having 1 - 4 carbon atoms, R2 denotes dialkylamino having 1 - 4 carbon atoms and X denotes nitrogen or -CR3 with R3 being phenyl which is optionally substituted by halogen, alkylamino or diaIkylamino groups or alkyl having 1 - 4 carbon atoms, a binder which is selected from the group ccmprising alkali-soluble binders, and a sensitizing dyestuff which comprises a cyanine dyestuff absorbing between 400 and 550 nm and an aminoxanthene dyestuff absorb ing be~ween 450 and 600 nm.
The photoconductor used in -the combination is conventional.
Oxadiazole derivatives are used, such as have been disclosed in German Patent No. 1,058,836, and especially 2,5-bis-(4'-diethylaminophenyl)-oxadiazole should be singled out as being particularly suitable. Triphenyloxazole derivatives, which are descriked in German Patent No. 1,120,875, can also be used according to the invention. Among the latter, 2-phenyl-4-(2'-chlorophe~yl)-5-(4"-diethyl-aminophenyl)-oxazole and 2,4-bis-(2'-chlorophenyl)-5-(4"-diethylaminophenyl)-oxazole are mention2d as being preferably 7~
suitable because of their superior electrophotographic properties.
Alkali-soluble binders of the present invention are high-molecular substances which carry groups con-ferring solubility in alkaline aqueous or alcoholicsolvent systems. Examples of such groups are acid, anhydride, carboxyl, phenol, sulfonic acid, sulfonamide or sulfonimîde groups. Binders having high acid numbers, especially of more than 100, are preferably em~loyed since these are particularly readily soluble in alkaline aqueous-alcoholic solvent systems. Copolymers of styrene and maleic anhydride, and ter~olymers o~ styrene, methacrylic acid and methacrylate are very particularly suitable.
Copolymers of methacrylic acid and methacrylate are also highly suitable.
~xamples of cyanine dyestuffs which are suitable according to the invention and which absorb in the wave-length region from 400 to 550 nm, include, for example, Astrazongelb 3G (C.I. 48,055), Astrazongelb 5G (C.I. 48,065) 20 or Basic Yellow 52,115 (C.I. 48,060). Also, suitable dyestuffs which have not yet been classified include Astrazonorange 3R, Astrazongelb 7GLL, Astrazongelb GRL
and Astragelb R. Further, Astrozonorange R (C.I. 48,040) and Astrazonorange G (C.I. 48,035) have proved particu-larly suitable. The proportion of cyanine dyestuffs, re-lative to the photoconductorj is preferably 0.001 to 0.1 part by weight.
Among the aminoxanthene dyestuffs absorbing between 450 and 600 nm, the Rhodamines are very suitable, - 30 particularlyRhodamineB andRhodamineFB (C.I. 45,170).
Their proportion, relative to the photoconductor, is pre-ferably 0.001 to 0.01 part by weight.
`~ The combination according to the invention is applied to supports, such as are conventionally used for the manufacture of printing forms for letterpress printing, planographic printing, gravure printing and for printed circuits. Suitable materials include aluminum, zinc, ., 7~
magnesium, copper or multi-metal plates. In particul æ cases, spe dal pa~ers or plastic films with vapor-deposited metal can also be used. Aluminum foils hav-ing improved surfaoe s have proved particularly suitable for planographic print-ing.
me surface of the ~support can be improved by mechanical or electro-chemical roughening and, in the case of aluminum, if appropriate, by subsequent anodizing and treatment with polyvinylphosphonic acid according to German Offenlegungsschrift No. 1,621,478, Other known processes for surfa oe improve-ment can be used for the preparation of a suitable support, for example, by silicatization. me surface improv~m~nt allows a longer print run and reduoe s the sensitivity to oxidation.
As conventional additives in the photoconductive layer, the recording material according to the invention can contain levelling agents, plasticizers and adhesion-prcmoters as well as a combination of those additives.
me present invention provides a recording material having outstanding properties. It is distinguished by a high light-sensitivity providing an e~po-sure time in the reprocamera which can be redu oe d to half of what is currently exeerienoe d with ccmmercially available materials. Discharge in the dæk is so slight that upon exposure the latent ch æge image produced has a high ch æ ge con-trast. After applying toner, an image can be reproduoe d with very sharp edgesand good resolution. Due to the high ch æge contrast, even fine screen dots in light tone-value ranges can be satisfactorily reproduced. l~oreover, discharge of the layers in the light leads to very low residual voltages so that images obtained after toner has been applied æe distinguished by superior freedom from background in the non-image areas. me spectral sensitivity falls steeply at 600 nm so that the layers can be handled under red light, without the occurren oe of image losses.
The printing forms manufactured using the photoconductive layers according to the invention are distinguished by a high stability during the printing run.
If suitable support materials are used, the lenqth of the printing run can be more than 100,000. If the photo-conductive layers are used for the manufacture of printedcircuits, excellent resistance to commercially available etches is ~ound.
The invention is explained in more detail by reference to the examples below.
The solution, described in Example 3 of German Patent No. 2,526,720,of 4S g of 2-vinyl-4-(2'-chloro-phenyl)-5-(4"-diethylaminophenyl)-oxazole, 45 g of a co-polymer of styrene and maleic anhydride, 2.25 g of Astrazonorange R in 280 g of tetrahydrofuran, 180 g of methylglycol and 84 g of butyl acetate is applied to a 300 ~m thick aluminum foil which has been electro-chemically roughened, anodized and treated with poly-vinylphosphonic acid. After the evaporation of the solvents,an approximately 5 ~m thick photoconductor layer remains. The layer is charged to -450 V using a coronoa and exposed for 26 seconds in a reprocamera having 10 halogen lamps of 600 Watts each. The original used is a paste-up of a newspaper page on a register sheet having blue orientation lines. The make-up contains, inter alia, a text on yellowed paper. A~ter applying toner to the latent charge image generated by the ex-posure, the blue orientation lines of the register sheet do not appear on the electrophotographic copy, but the text on the yellowed paper is reproduced with back-ground.
~ ccording to the invention, 40 g of 2-phenyl-4-(2'-chlorophenyl)-5~(4"-diethylaminophenyl)-oxazole and 60 g of a copolymer of styrene and maleic anhydride are dissolved in a solvent mixture consisting of 400 g of tetrahydrofuran, 200 g of methylglycol and 100 g of butyl acetate. 30 g of methanolic solution of 2 g of ~467~
Astrazonorange R (C.I. 48,040) and 0.2 g of Rhodamin B (C.I. 45,170) are also added to the solution. This resulting solution is used for coating the same support material so that after evaporation of the solvents, a photoconductor layer of 5 ~m thickness is obtained. After charging the layer to -450 V, the layer is exposed in the same reprocamera with the same light souroe s, and using the same original. Although the layer of the present example contains only 40%
of photoconductor instead of 50~ as described in Example 3 of German Patent No.
2,526,720, only 13 seconds are required for exposure. After applying toner, an image completely free from background is obtained without the blue orientation lines being reproduced.
The manufacture of the printing forms is carried out by the process described in German Patent No. 1,117,391.
An aluminum foil having a surfaoe mechanically roughened by wire-brushing is coated with a solution of 20 g of 2,4-bis-(2'-chlorophenyl)-5-(4"-diethylaminophenyl)-oxazole; 30 g of a oopolymer of styrene and maleic anhydride in 240 ml of tetrahydrofuran; 150 ml of methylglycol and 60 ml of butyl aoetate;
and 20 ml of a methanolic sensitizer solution containing 1 g of Astrazongelb 7 T.T. (C.I. Basic Yellow 21) and 0.1 g of Rhodamine FB (C.I. 45,170). After the evaporation of the solvents, an approximate~y 5 ~m thick photoconductor layer is obtained and is negatively charged to about -450 V in the dark with the aid of a corona. The charged photoconductor layer is exposed for 15 seconds in a re-procamera having 8 Autophot lamps of 500 Watts each. The original used is a conventional newspaper paste-up sheet having blue orientation lines and yellowed text sections pasted in. After the application of a commercially available toner to the latent charge image generated by the exposure, a clean, sharp, background-free image of the '7~
g oriyinal is obtained and fixed by the action of heat.
For conversion to a printing form, the aluminum foil having the photoconductor layer and toner is introduced into a cell containing a solution of 35 g of sodium meta-silicate 9H2O in 140 ml of glycerol having a watercontent of 20%, 550 ml o ethylene glycol and 140 ml of ethanol. After one minute, the photoconductor layer having been incipiently dissolved in the toner-free areas is rinsed with a water jet while gently rubbing to prepare the plate for printing. The printing run can be as much as 80,000, by virtue of the support matexial used. If printing is not carried out until a later time, the plate must be preserved by means of a commercially available preserving or gumming solution.
An aluminum foil having an electrochemically roughened and anodized sur~ace which has been treated with polyvinylphosphonic acid is coated with a solution of 20 g of 2-phenyl-4-(2l-chlorophenyl)-5-(4"-diethylamino-phenyl~-oxazole and 30 g of a copolymer of styrene and maleic anhydride in a solvent mixture consisting of 240 ml of tetrahydrofuran, 150 ml of methylglycol and 60 ml of butyl acetate to which 20 ml of a methanolic solution of 1 g of Astrazonorange R (C.I. 48,040) and 0.1 g ofRhodamineFB (C.I. 45,170) is added. After re-moval of the solvents, an electrophotographic printing plate having an approximately 5 ~m thick photoconductor layer is ~btained. For further processing, the plate is placed into an automatic machine, such as is com-mercially available for the preparation of newspaper - printing forms,and the plate is charged and exposed at 488 nm with a 10 m~ argon ion laser Then, toner is applied to the plate and fixed. At 488 nm, an energy density of about 30 ~J/cm2 is necessary for discharging the photoconductor layer rom 450 V to a residual voltage of 50 V. The total imaging time for a printing plate of newspaper size (378 x 587 mm) in the automatic :
~ `~
machine is about 4 minutes of which about 80 seconds re-presents the time required for exposure if the laser is operated at half its output power. After the application of toner, the plate is converted into a printing form by dissolving the photoconductor layer away from the toner-free areas, as described in Example 2. Approximately 150,000 impressions can be prepared from the printing form on a rotary of:fset press.
A solution is obtained by dissolving 20 g of 2,5-bis-(4-diethylaminophenyi)-i,3,4-oxadiazole and 30 g of a copolymer of 806 of methyl methacrylate and 20% of methacrylic acid in a soIvent mixture consisting of 240 ml of tetrahydrofuran ! 150 ml of methylglycol and ; 15 60 ml of butyl acetate. Also 20 ml of a methanolic solution of 1 g of Astrazonorange G (C.I. 48,035) and 0.1 g of RhodamineFB ~C.I. 45,170) is added to the solution, which is then applied to a copper-laminated phenolic resin laminate adapted for the manufacture of printed circuits. After evaporation of the solvents, the approximately 5 ~m thick photoconductor layer is negatively charged to-450 V with the aid of a corona and is exposed to generate the image of a printed circuit thereon. On contact exposure in a copying frame, the exposure time is 2 seconds, using a 100 Watt incandescent lamp at a distance of 60 cm. After applying toner and fixing, the photoconductor layer is dissolved away from the toner-free areas, in the manner described in Example 2. Subsequently, the bared copper is removed 3Q by means of a commercially available etch. By washing with a solvent, for example a ketone, the printed circuit track consisting of copper is freed from toner and photoconductor layer.
The manufacture of the printing forms is carried out by the process described in German Patent No. 1,117,391.
An aluminum foil having a surfaoe mechanically roughened by wire-brushing is coated with a solution of 20 g of 2,4-bis-(2'-chlorophenyl)-5-(4"-diethylaminophenyl)-oxazole; 30 g of a oopolymer of styrene and maleic anhydride in 240 ml of tetrahydrofuran; 150 ml of methylglycol and 60 ml of butyl aoetate;
and 20 ml of a methanolic sensitizer solution containing 1 g of Astrazongelb 7 T.T. (C.I. Basic Yellow 21) and 0.1 g of Rhodamine FB (C.I. 45,170). After the evaporation of the solvents, an approximate~y 5 ~m thick photoconductor layer is obtained and is negatively charged to about -450 V in the dark with the aid of a corona. The charged photoconductor layer is exposed for 15 seconds in a re-procamera having 8 Autophot lamps of 500 Watts each. The original used is a conventional newspaper paste-up sheet having blue orientation lines and yellowed text sections pasted in. After the application of a commercially available toner to the latent charge image generated by the exposure, a clean, sharp, background-free image of the '7~
g oriyinal is obtained and fixed by the action of heat.
For conversion to a printing form, the aluminum foil having the photoconductor layer and toner is introduced into a cell containing a solution of 35 g of sodium meta-silicate 9H2O in 140 ml of glycerol having a watercontent of 20%, 550 ml o ethylene glycol and 140 ml of ethanol. After one minute, the photoconductor layer having been incipiently dissolved in the toner-free areas is rinsed with a water jet while gently rubbing to prepare the plate for printing. The printing run can be as much as 80,000, by virtue of the support matexial used. If printing is not carried out until a later time, the plate must be preserved by means of a commercially available preserving or gumming solution.
An aluminum foil having an electrochemically roughened and anodized sur~ace which has been treated with polyvinylphosphonic acid is coated with a solution of 20 g of 2-phenyl-4-(2l-chlorophenyl)-5-(4"-diethylamino-phenyl~-oxazole and 30 g of a copolymer of styrene and maleic anhydride in a solvent mixture consisting of 240 ml of tetrahydrofuran, 150 ml of methylglycol and 60 ml of butyl acetate to which 20 ml of a methanolic solution of 1 g of Astrazonorange R (C.I. 48,040) and 0.1 g ofRhodamineFB (C.I. 45,170) is added. After re-moval of the solvents, an electrophotographic printing plate having an approximately 5 ~m thick photoconductor layer is ~btained. For further processing, the plate is placed into an automatic machine, such as is com-mercially available for the preparation of newspaper - printing forms,and the plate is charged and exposed at 488 nm with a 10 m~ argon ion laser Then, toner is applied to the plate and fixed. At 488 nm, an energy density of about 30 ~J/cm2 is necessary for discharging the photoconductor layer rom 450 V to a residual voltage of 50 V. The total imaging time for a printing plate of newspaper size (378 x 587 mm) in the automatic :
~ `~
machine is about 4 minutes of which about 80 seconds re-presents the time required for exposure if the laser is operated at half its output power. After the application of toner, the plate is converted into a printing form by dissolving the photoconductor layer away from the toner-free areas, as described in Example 2. Approximately 150,000 impressions can be prepared from the printing form on a rotary of:fset press.
A solution is obtained by dissolving 20 g of 2,5-bis-(4-diethylaminophenyi)-i,3,4-oxadiazole and 30 g of a copolymer of 806 of methyl methacrylate and 20% of methacrylic acid in a soIvent mixture consisting of 240 ml of tetrahydrofuran ! 150 ml of methylglycol and ; 15 60 ml of butyl acetate. Also 20 ml of a methanolic solution of 1 g of Astrazonorange G (C.I. 48,035) and 0.1 g of RhodamineFB ~C.I. 45,170) is added to the solution, which is then applied to a copper-laminated phenolic resin laminate adapted for the manufacture of printed circuits. After evaporation of the solvents, the approximately 5 ~m thick photoconductor layer is negatively charged to-450 V with the aid of a corona and is exposed to generate the image of a printed circuit thereon. On contact exposure in a copying frame, the exposure time is 2 seconds, using a 100 Watt incandescent lamp at a distance of 60 cm. After applying toner and fixing, the photoconductor layer is dissolved away from the toner-free areas, in the manner described in Example 2. Subsequently, the bared copper is removed 3Q by means of a commercially available etch. By washing with a solvent, for example a ketone, the printed circuit track consisting of copper is freed from toner and photoconductor layer.
Claims (13)
1. An electrophotographic recording material comprising:
an electrically conductive support; and a photoconductive layer on said support including a photoconductor having the formula I
I
wherein R1 is a member of the group consisting of hydrogen, an alkyl radical, an alkoxy radical, both having between 1 and 4 carbon atoms, halogen, and a dialkylamino radical having between 1 and 4 carbon atoms;
R2 is a member of the group consisting of a dialkylamino radical having between 1 and 4 carbon atoms;
X is a member of the group consisting of nitrogen and -CR3, wherein R3 is a phenyl radical optionally substituted by halogen, a monoalkylamino radical, a dialkylamino radical or an alkyl radical having between 1 and 4 carbon atoms;
a binder selected from the group consisting of alkali-soluble binders; and a sensitizing dyestuff comprising a cyanine dyestuff absorbing between 400 and 550 nm and an amino-xanthene dyestuff absorbing between 450 and 600 nm.
an electrically conductive support; and a photoconductive layer on said support including a photoconductor having the formula I
I
wherein R1 is a member of the group consisting of hydrogen, an alkyl radical, an alkoxy radical, both having between 1 and 4 carbon atoms, halogen, and a dialkylamino radical having between 1 and 4 carbon atoms;
R2 is a member of the group consisting of a dialkylamino radical having between 1 and 4 carbon atoms;
X is a member of the group consisting of nitrogen and -CR3, wherein R3 is a phenyl radical optionally substituted by halogen, a monoalkylamino radical, a dialkylamino radical or an alkyl radical having between 1 and 4 carbon atoms;
a binder selected from the group consisting of alkali-soluble binders; and a sensitizing dyestuff comprising a cyanine dyestuff absorbing between 400 and 550 nm and an amino-xanthene dyestuff absorbing between 450 and 600 nm.
2. A recording material as claimed in Claim 1, including a photoconductor of the formula I, wherein R1 is a member of the group consisting of hydrogen, halogen and a dialkylamino radical having between 1 and 4 carbon atoms.
3. A recording material as claimed in Claim 1, including a photoconductor of the formula I, wherein R1 is a member of the group consisting of hydrogen, halogen and a dialkylamino radical having between 1 and 4 carbon atoms and R3 is a phenyl radical optionally substituted by halogen.
4. A recording material as claimed in Claim 1, wherein the photoconductive layer contains 2,4-bis-(2'-chlorophenyl)-5-(4"-diethylaminophenyl)-oxazole as the photoconductor.
5. A recording material as claimed in Claim 1, wherein the photoconductive layer contains 2-phenyl-4-(2'-chlorophenyl)-5-(4"-diethylaminophenyl)-oxazole as the photoconductor.
6. A recording material as claimed in Claim 1, wherein the photoconductive layer contains 2,5-bis-(4'-diethylaminophenyl)-1,3,4-oxadiazole as the photoconductor.
7. A recording material as claimed in Claim 1, 4 or 5, wherein said photoconductor layer contains a copolymer as said binder comprising a styrene/maleic anhydride copolymer.
8. A recording material as claimed in Claim 1, 4 or 5, wherein said photoconductive layer contains a terpolymer of styrene, methacrylic acid and methacrylate as said binder.
9. A recording material as claimed in Claim 1, 4 or 5, wherein said photoconductive layer contains a copolymer of methacrylic acid and a methacry-late as said binder.
10. A recording material as claimed in Claim 1, 4 or 5, wherein said photoconductive layer contains a mixture of Astrazonorange R (C.I. 48,040) and Rhodamine FB (C.I. 45,170) as said sensitizing dyestuff.
11. A recording material as claimed in Claim 1, 4 or 5, wherein said sup-port comprises an aluminum foil having a mechanically roughened surface.
12. A recording material as claimed in Claim 1, wherein said support com-prises an aluminum foil having a surface which is electrochemically roughened and anodized.
13. A recording material as claimed in Claim 12, wherein said support has a surface which is treated with a member of the group consisting of polyvinyl-phosphonic acid and silicate.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19792949826 DE2949826A1 (en) | 1979-12-12 | 1979-12-12 | MATERIAL FOR ELECTROPHOTOGRAPHIC REPRODUCTION |
| DEP2949826.8 | 1979-12-12 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1146794A true CA1146794A (en) | 1983-05-24 |
Family
ID=6088159
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000366136A Expired CA1146794A (en) | 1979-12-12 | 1980-12-04 | Electrophotographic reproduction material including an oxazole photoconductor and a combination of cyanine and xanthene sensitizing dyes |
Country Status (10)
| Country | Link |
|---|---|
| EP (1) | EP0031481B1 (en) |
| JP (1) | JPS56107246A (en) |
| AT (1) | ATE12011T1 (en) |
| AU (1) | AU539930B2 (en) |
| BR (1) | BR8008096A (en) |
| CA (1) | CA1146794A (en) |
| DE (2) | DE2949826A1 (en) |
| ES (1) | ES8204539A1 (en) |
| FI (1) | FI803838L (en) |
| ZA (1) | ZA807766B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4880718A (en) * | 1987-11-28 | 1989-11-14 | Basf Aktiengesellschaft | Electrophotographic recording element with isoindolenine derivatives |
| US4906541A (en) * | 1987-11-28 | 1990-03-06 | Basf Aktiengesellschaft | Electrophotographic recording element containing a naphtholactam dye sensitizer |
| US4985323A (en) * | 1987-09-29 | 1991-01-15 | Fuji Photo Film Co., Ltd. | Electrophotographic printing plate |
| US5328797A (en) * | 1989-11-23 | 1994-07-12 | Hoechst Aktiengesellschaft | Process for producing a negative-working lithographic printing form utilizing solvent mixture of mono-(C1 -C4) alkyl ether of diethylene glycol and a solvent having boiling point between 50° and 150° C. |
| US6376144B1 (en) | 2000-08-03 | 2002-04-23 | Kodak Polychrome Graphics, Llc | Organic photoconductive composition |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL8402805A (en) * | 1984-09-13 | 1986-04-01 | Oce Nederland Bv | METHOD FOR COPYING AND ELECTROPHOTOGRAPHIC ELEMENT. |
| DE3514182A1 (en) * | 1985-04-19 | 1986-10-23 | Basf Ag, 6700 Ludwigshafen | ELECTROPHOTOGRAPHIC RECORDING MATERIAL |
| 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 |
| DE19510526A1 (en) * | 1995-03-23 | 1996-09-26 | Hoechst Ag | Electrophotographic recording material for the production of printing plates |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE585507A (en) * | 1960-03-31 | |||
| FR1375297A (en) * | 1962-09-21 | 1964-10-16 | Kalle Ag | Sensitive layers for electrophotography and method of preparation thereof |
| DE1447907A1 (en) * | 1964-01-11 | 1968-12-05 | Kalle Ag | Multicolor electrophotographic printing |
| US3545969A (en) * | 1965-07-26 | 1970-12-08 | Ibm | Method of inducing an electrostatic charge pattern on an insulating surface |
| DE2817428A1 (en) * | 1978-04-21 | 1979-10-31 | Hoechst Ag | MATERIAL FOR ELECTROPHOTOGRAPHIC REPRODUCTION |
-
1979
- 1979-12-12 DE DE19792949826 patent/DE2949826A1/en not_active Withdrawn
-
1980
- 1980-12-04 AT AT80107575T patent/ATE12011T1/en not_active IP Right Cessation
- 1980-12-04 DE DE8080107575T patent/DE3070246D1/en not_active Expired
- 1980-12-04 EP EP80107575A patent/EP0031481B1/en not_active Expired
- 1980-12-04 CA CA000366136A patent/CA1146794A/en not_active Expired
- 1980-12-10 FI FI803838A patent/FI803838L/en not_active Application Discontinuation
- 1980-12-10 AU AU65221/80A patent/AU539930B2/en not_active Ceased
- 1980-12-11 ES ES497639A patent/ES8204539A1/en not_active Expired
- 1980-12-11 BR BR8008096A patent/BR8008096A/en not_active IP Right Cessation
- 1980-12-11 ZA ZA00807766A patent/ZA807766B/en unknown
- 1980-12-12 JP JP17479380A patent/JPS56107246A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4985323A (en) * | 1987-09-29 | 1991-01-15 | Fuji Photo Film Co., Ltd. | Electrophotographic printing plate |
| US4880718A (en) * | 1987-11-28 | 1989-11-14 | Basf Aktiengesellschaft | Electrophotographic recording element with isoindolenine derivatives |
| US4906541A (en) * | 1987-11-28 | 1990-03-06 | Basf Aktiengesellschaft | Electrophotographic recording element containing a naphtholactam dye sensitizer |
| US5328797A (en) * | 1989-11-23 | 1994-07-12 | Hoechst Aktiengesellschaft | Process for producing a negative-working lithographic printing form utilizing solvent mixture of mono-(C1 -C4) alkyl ether of diethylene glycol and a solvent having boiling point between 50° and 150° C. |
| US6376144B1 (en) | 2000-08-03 | 2002-04-23 | Kodak Polychrome Graphics, Llc | Organic photoconductive composition |
Also Published As
| Publication number | Publication date |
|---|---|
| ATE12011T1 (en) | 1985-03-15 |
| EP0031481B1 (en) | 1985-02-27 |
| ZA807766B (en) | 1981-12-30 |
| BR8008096A (en) | 1981-06-30 |
| AU6522180A (en) | 1981-06-18 |
| FI803838L (en) | 1981-06-13 |
| ES497639A0 (en) | 1982-05-01 |
| JPS56107246A (en) | 1981-08-26 |
| DE3070246D1 (en) | 1985-04-04 |
| AU539930B2 (en) | 1984-10-25 |
| DE2949826A1 (en) | 1981-06-19 |
| ES8204539A1 (en) | 1982-05-01 |
| EP0031481A1 (en) | 1981-07-08 |
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