DE1772511A1 - Electrophotographic copying material and process for its manufacture - US Pat - Google Patents

Description

■ jhiki Kainlifer'üiÄWi 2 β. MAY 1968

), Japan

Elektrophotorera p hisuh.es xCopienuaturial mid process for your production;

The I] rfiudun {j relates to an electrophotographic printing material with a photoconductive organic substance containing photosensitive layer and a Verfali-ι · οη to ο a presentation.

. ■ The numerous photoleitflLhige organic substances νάο poly-Ii-vinylcarbazole, bekamit, of which, however, the: ίο.Ujten only Ul braviolett-Liclitstrahlen with Wellenirin {; eii ir.i range un ^ j ¹ J n / absorb U, \ 7emi this Substiuizon · /: ■: ■■: Herst oll im · -; of; pi'al: tisoh usable copy materials should have been used, therefore their light reflection must also be extended to the wave range of visible light. JiIiJ isb also uokaturl., The Lioltoeriprindlichlceit d: i -.uuV photüloitrühisou Üubstfuizen ' itruh Zu ^ a]) (J olnes ii <: iir. Lhil.i ütu-ori; in. Ι ·' ¹ οιί.ι tdno ;: i; 'arb- '.;',■> i "''a:; ov / ie cdnes HiLi'ssonsiiii" Lisators in Wolw an n'iS LIr; t; allliii.Lo ;; c: i! Ι, · ;, 'Jlunons, tCotons>). D. ; L. :; u

i Lo-

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graphic copy material rait a light-sensitive Layer has been proposed to be an auxiliary sensitizer of the aforementioned type in conjunction with a light-sensitive making dye and a photoconductive SuTostaiia contains. However, such an electrophotographic copying material has those mentioned below IT eight eil ο with regard to its manufacture and its elelrfcrofe static properties.

If, for example, a metal halide such as zinc or zinc chloride (IV) chloride, or an acid such as salt, sulfur or phosphoric acid was used as an auxiliary sensitizer, the electrophotographic copying material obtained in this way had the IT eight speed that the its photosensitive layer was insufficiently charged by Coroiia discharge and it took a long period of time to reach a saturation potential. When an acid such as dichloroacetic acid, srichloroacetic acid, or picric acid, or an acid anhydride was used, the electrophotographic copying material obtained also had the laugh that its photosensitive layer exhibited noticeable "light fatigue", which resulted in the chargeable layer of the rental-sensitive layer voi / sehlechtort, if it is exposed before the opening of a olokU'Ltschou Liiuung, and that this lCo _L jiof _: taboL'ial also had a nchlechbo rechargeable battery, äuoh wona va by GotOiui-

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Discharge should be charged. TZemi the solution for Manufacture of photosensitive. Layer by dispersing an aforementioned metal halide in one photoconductive organic substance in a dispersion medium was produced, she pointed out regarding the production of copying material also have the disadvantage that they can be used if left to stand for a long time, for example 1 day Gels tended to form, causing considerable difficulty for their application to the surface of the support sheet revealed.

The object of the invention is therefore to provide an electrophotographic copying material having a containing photoconductive organic substance of the aforementioned type photosensitive layer which is identical to conventional electrophotographic copying materials adhering specialist parts are largely switched off and which is characterized by advanced properties, in particular thanks to quick recharge, high saturation potential as well as low "light fatigue". In particular the invention provides an electrophotographic Copy material which, in addition to other favorable properties, has markedly improved electrostatic properties and has a carrier sheet, the reverse side of which is a Electroconductivity treatment and its pre-

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dereeito in the V / eise "was dealt with initially impregnated or coated with an auxiliary sensitizer and then a photoconductive organic one Substance-containing photosensitive layer formed on the front side pretreated with the auxiliary sensitizer became.

Upon closer examination of the numerous disadvantages more well known electrophotographic copying materials found that the mentioned !! disadvantages can be attributed to it are that in the course of the formation of the photosensitive layer from a mixture of photoconductive substance, sensitizing dye and auxiliary sensitizer a reaction between auxiliary sensitizer and οeiisibiliGierendem Dye or alternatively auxiliary sensitizer and photoconductive Substance enters, which causes gelling of the layer or the formation of uiiervAinschten or harmful Products which result in a deterioration in the photosensitive properties of the photoconductive layer cause. In addition, it was observed that one for forming photosensitive layers from a mixture of the foregoing The type of prepared solution is subject to strong lateral changes.

The invention is based on the aforementioned sub-

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Searches GiItWiC] ZoIt been. More precisely * there is one knowledge according to the invention is that a previous Irach ^ eilc deactivating electrophotographical photographic material can be created in that first an auxiliary sensitizer on or in the front of a carrier sheet is applied or introduced, the back of which has been subjected to an electrical conductivity treatment, and that then an organic, phobo-conductive substance containing light sensitive layer on the with the auxiliary sensitizer is applied pretreated front side.

The photosensitive layer of the inventive electrophotographic copier material produced in this way has the nature that the auxiliary sensitizer applied to or in the original sheet diffuses uniformly through the photosensitive layer. Therefore, the photosensitivity of the photosensitive layer in the vicinity of the support sheet is greater. I lithiα lot the electrophotographic copying material according to the invention completely free from the disadvantages found in the known iConixnvialori £ tlion of this type. uar "> jj: 'hijuai: i offered -is orfindiuigijgemäß dor advantage that i; only dio Liohbompfindlichkeit the KoplarmaLorlrXls, ora iaicili!.' lav D [JO ^ Ifischo oloJct" isclio y / idorfjtatid dcü

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Carrier sheet can be adjusted freely at will, by the type and length of the applied to the carrier sheet Auxiliary sensitizer and the conditions under which the applied auxiliary sensitizer is dried can be varied will. For example, the surface of the carrier sheet becomes after the application of an auxiliary sensitizer caution at a relatively low temperature of 60 - 100 0 dried. By applying a photosensitive “Layer on the one with yours. Auxiliary seiiaibilisatoi 'pretreated Carrier sheet front scite there are the advantages, that not only the distribution of the auxiliary sensitizer into the photosensitive layer, but also the electroconductivity of the carrier sheet is greatly improved, creating an olektrophotographic copying material with the desired photosensitivity and desired electrical resistance is created. It is believed that these important features of the electrophotographic of the present invention Copy material thereby ensures that the auxiliary sensitizer contained in the photosensitive layer evaporates or sublimates during the drying of the layer and thereby uniformly into the light-sensitive Layer diffused into it. Consequently, the photosensitive Do not cover areas in which the iliac sensitiser would be present in local excess, whereby, el :: L · electric '"' position of the light-sensitive

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Layer kept in a desirable area and on the other hand, the electrical conductivity of the Iräger-IdIatts is improved.

Auxiliary sensitizers which can be used according to the invention are for example, organic carboxylic acids or organic

Sulfonic acids, such as ivlonochloroacetic acid, dichloroacetic

■ acid, irichloroacetic acid, tetrachlorophthalic acid, phenylacetic acid, Phthalic acid, 6-Ilethylcumariiiylessigsäure, Malic acid, benzoic acid, cinnamic acid, 4-toluenesulfonic acid and benzenesulfonic acid; I. metal halides, such as zinc chloride, Tin (II) chloride, zinc (17) chloride, aluminum chloride,. ITiekelclilorid, Eisen (II) -chloride, Kupfer (I) -chloride, Bariuinclilorid, ITodium chloride, calcium chloride, lithium chloride, titanium trichloride, arsenic trichloride, antimony pentachloride, laghesium chloride, magnesium bromide, potassium bromide, Calcium iodide, stroiitium bromide, chromium bromide, manganese (II) chloride, Cerium (IV) -chloride, cerium (III) -bronide, mercury chloride and arsenic triiodide; Boron halides such as boron trifluoride and boron trichloride; Quinones, such as benzoquinone- (1,4) »2,5-diclilorbaoquinone, 2, G-dichlorobensochinoii, chloranilnaphthoquinone- (1,4) »2, J-Dichloriiaphthoquinone- (1,4)» Antlirachinon, 2-I, iethylanthrachiiiOii, 1,4-Dimethylanthraquinone, I-Cliloraiithraquinone, Antlirachinon ^ -carboxylic acid, 1, ^ -Dichloranthraquinone, T-chloro-4-nitroanthraquinone,

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Phenanthrene quinone, Ac enaplitho quinone, Pyrananthr achiiion, chrysenequinone, Shionaphthenquinone, Antliracliiiioii-1,3-diaulfonic acid and 2-anilide-1,4-iaphthocliinoni3ulfonic acid; Aldehydes, such as bromal, 4-ilitrobenzaldehyde, 2,6-chlorobenzaldehyde, 2-ethoxy-1-iaphthaldehyde, oxyidol-3-aldehyde, pyridine-2,6-aldehyde, biphenyl-4-aldehyde and furfural ; Ketones such as acetophenone, beiizoplieiion, 2-acetyliiaphthalene, benzylbenzoin, 5- beiizoylacenaphthalen, 9-acetylanthracene, 9-benzoylanthraoene and acetoacetic anilide; Salts such as cilium nitrate, aluminum nitrate, magnesium nitrate, sodium formate, magnesium acetate, potassium acetate, potassium tartrate, ammonium citrate, egg (III) sulfate, zirconium acetate, magnesium sulfate and tin chromate; Halides or nitrides, such as styrene chloride, 1,3-dinitrobenzene, 1-l-nitro-2-dichlorobenzene, tricyanobenzene, trinitrobenzene, 1-nitro-3,4-dichlorobenzene, 5-chloro-2-nitroaniline, 2,4JO-I ¹ ^ iIiItI- ¹ OaIIiSoI, Pilcrylchlorid, Totrabroi-ucylol, 1 ^ - Mcliloniapiitlialin, 1,3-Diclilornaphthaliii, 1 ^ -Dinitronaphthaliii, 1, S-Diclilomitronaplithalin, 4-lIitrodip] ienylbeiisocsü.ure, 4 '4 ¹ -Miiitrodiplicnylboiisoesäure' Nitrobenzoic acid, iodoform, picric acid, tetracycline ethyl nylon and 4-nitroacenaphthyl; and aiiorganisclio acids such as hydrochloric acid, sulfuric acid, phosphoric acid and nitric acid. These auxiliary sensitizers have been used by dissolving them in a solvent such as water,!,! Ethanol or toluene, and the resulting

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Solution applied to the front of a carrier sheet will.

Carrier sheets that can be used according to the invention consist, for example, of tracing paper, high-quality paper, art paper, Baryta paper or polyester film, the back of which has been subjected to a conventional conductivity treatment. If a metal plate is used as the carrier sheet, this serves as a printing plate after treatment according to the invention.

Photoconductive organic compounds which can be applied according to the invention Substances are e.g. compounds with heterocyclic and condensed rings, such as poly-lJ-vinylcarbazole, poly-dimethylaminoacenaphthylene, Poly-U-vinyl-nitrocarbazole, Poly-IT-dimothylaninocarbazole, polyvinyl anthracene, polyvinyl nitronaphthalene and their polymers.

ErfiiLdmigsgenäß useful sensibilisierendo dyes are Rhodamine G, Rhodamine B _p rhodamine S, Methylviolott, ethyl violet, crystal violet, methylene blue 3? Z, methylene blue BII cone, Victoria blue B, brilliant green GX, Ualachitgriüi, auramine G cone, and Acridinorange ITS.

. Dan Mater · use of the aforementioned constituents OF INVENTION ~ di.tN, "n -; ^on: ISS horgea tollt ο elüktrophotographiache Kopiermato-

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rial can be charged to a sufficiently high potential through corona discharge. The electrophotographic copying material according to the invention therefore has a photosensitivity which is by far superior to that of conventional copying materials of this type. In addition, the electrophotographic copying material according to the invention can be produced very easily. Furthermore, the solution prepared according to the invention and applied to a carrier sheet is perfect of the known G-elbildungs phenomena conventional solutions, v ^r odurch ensures clear that it can be evenly applied to the carrier sheet front side. the Satsacht ¹ ate the present invention prepared solution is not subject to lateral changes manufacturability elektrophotographiacher copying materials guaranteed by Consistent quality and uniform properties through the simultaneous use of an electrically conductive material such as polyglycol, surface-active agent or synthetic resin when impregnating the carrier sheet with the auxiliaries As a sensitizer, there is also provided an electrophotographic copying material with far improved photosensitivity.

The following is the invention in terms of preferred Auofülinuigoforms Darnteilenden examples described.

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BATH ORIGINAL example 1

An auxiliary sensitizer solution made from 5 β concentrated nitric acid with 95 g of ethanol was applied evenly to the front side of a carrier sheet made of high quality paper, the rear side of which was subjected to a conductivity treatment using, for example, surface-active Ilittoln v / ai ", v / o was evenly impregnated with the solution through the Voi'derseite. The applied solution was ^{dried at 80 °} C. for 1 min. Vinylcaroasol in llonochlorbeiicol with an E ¹ IIm.-thick - by niVcJ ". Λοη Aufrollverfaliren a 5 gev /.-^ solution of poly" formed photosensitive layer, a licJri: ir with the auxiliary sensitizer pretreated front: on was then i > plotted from 4 »0 yii vau ^ de. This photosensitive layer was LVmin getroclaiet at 115 ⁰ C long, which her attracteth glee it sgeialt to $ 410 adjusted γ / urde and elektropjiotcgraphiscli. ■ Copy material alien have been kept. In addition to the v.Tirden, the same copier materials are produced in that the solvent-sensitive layer is formed by a medium base. the I: ci; ion Ul ^ ersug, in the form of the auxiliary sensitizer, is applied on the front of a carrier sheet made of similar high quality paper and similar, as described oboii, getroclaiot vau? de. '

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The "copy materials of these" two groups was made respectively A negative charge was pressed on by Coroiia discharge of 6 kV. Then the Kopiermaterialioii were through a placed original for 3 seconds 'exposed to a 200 \ 7att- \ 7olfram incandescent lamp and placed in a ITass development process developed. This resulted in on the front side of the copy materials according to the invention a high-contrast copy faithfully reproducing the original. In contrast, those with the comparative copy materials were copies obtained due to their poor sensitivity to visible light are very blurred and practically unusable.

Example 2

A photosensitive layer-forming solution was applied to the auxiliary sensitizer, which had been prepared according to Example 1 and applied to the front side of the high-quality paper, using the roll-up method with a film thickness of 4 »5 / rev Ji (1% by weight methanolic solution) was obtained on 100 g of a 5% by weight solution of poly-N-vinylcarbazole in monochlorobenzene. The resulting layer was dried to adjust the moisture content to 4.5 $ for 5 minutes at 120 ⁰ C, whereby electrophoto-

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graphic copy material was created. Also were Comparative copy materials produced by also v / ie in the case of the copier materials according to the invention, the aforementioned, a solution which forms a light-sensitive layer was applied directly to the carrier sheets, which consisted of the high quality paper used in Example 1 and to regulate the moisture content in were dried in the same way as the copying materials according to the invention.

The surface of the photosensitive layer of both coping material groups each became a negative charge pressed on, and the copy materials were exposed as in Example 1. The drop in potential occurred here or the Lient weakening of the light-sensitive layer in the copy materials according to the invention about eight times as fast as the comparison copy materials.

Example 3

An auxiliary oil bilioator solution obtained by dissolving 1 g of picric acid in 99 g of methanol was ^{applied evenly in an amount of 0.03 c / m 2} to the front side of carrier sheets on paper, the information of which was Bchandlimg been included

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was. After drying the auxiliary sensitizer at 60 ^° C. for 1 minute, a 5% strength by weight solution of poly-IT-vinylcarbazole in monochlorobenzene was applied to it with a film thickness of 3.0 / u. The photosensitive layer thus produced was 2 their moisture content was adjusted to s ^ IOF / o min dried at 120 ⁰ C, whereby .. and "cdctrophotograpliifjche copying materials were obtained. In addition, comparative copier materials were produced by applying the above-mentioned "photosensitive layer" -forming solution to the front side of similar carrier sheets, which, however, had not been provided with an auxiliary sensitizer, and regulating their moisture content by drying, just as in the production of the copier materials according to the invention .

The light sensitivity of the copying materials is now reduced measured both groups, it was found that the inventive copy materials practical for the The entire visible range is light-sensitive, while the comparative copy materials have maximum light-sensitivity possessed only for light of wavelength 355 m / u. In addition, the copy materials of both groups similar to example 1, electrostatic latent images are applied and the copiormatorialion according to dom Trocküiieut-

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wickluiigsverfahreii developed. This resulted in the The surface of the inventive copier materials has a very clear copy, while the copies on the comparative copy materials were extremely fuzzy.

Example 4-

A solution which forms a photosensitive layer and which can be prepared by adding 1.4 g of a 1.0% strength by weight methanol! Methylene blue FZ solution to 100 g of a 5.0% strength by weight solution of poly-IT-vinylcarbazole v / ar obtained in monochlorobenzene was applied to paper pretreated with an auxiliary sensitizer according to Example 3 by a roll-up process with a film thickness of 4.0 / u, whereby a photosensitive layer was formed on each carrier sheet. The photosensitive ^ chichten were characterized condition for adjusting the moisture content to 4 * 5 $ 3 min at 12O ⁰ O and dried elelctrophotographische copying materials. In addition, comparative copy materials were produced by applying the above-mentioned, photosensitive layer-forming solution directly to the front side of Srägerblätterii according to Example 3 and adjusting the moisture content of the layer by drying as in the production of the copying material according to the invention. .

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Now the electrostatic properties have been obtained Copy materials "of both groups measured and compared with one another. The result is from the graphic Representation can be seen in which the ordinate shows the surface potential (in volts) of the light-sensitive layers after applying a negative charge by means of a 6 IcV corona discharge and the abscissa indicates the time (in seconds). The illustration thus illustrates how in each case the surface potential of the copy materials after charging has ended when the photosensitive materials are exposed Shift changed. Curve 1 relates to the copying materials according to the invention and curve 2 on the comparison copy materials.

As can be seen from the graphic representation, the copy materials according to the invention have after completion Charge a saturation potential about twice as high like the comparison copy materials, but at the same time a very rapid drop in potential on exposure. The half-life of the potential drop in the inventive Copy materials is only about one twelfth of the half-life of the comparison copy materials. It can be seen that the invention Copy material ion very good for electropiiotographioche Sonell copying methods are suitable.

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Example 5

An auxiliary sensitizer solution prepared by dissolving 5 g of zinc chloride in 95 g of methanol was uniformly in an amount of 0.1 g / m. applied to the front side of carrier sheets made of matt oak paper, the rear side of which had been subjected to an electroconductivity treatment. llach 1 minute, drying the Hilfssensibilisators at 70 ⁰ C was treated with a lilmdicke of 3.5 / U a a photosensitive layer "forming solution obtained by adding 1, Qg of a 1 wt .- ^ ICristallviolett methanolic solution to 50 g was prepared a 5> 0 gev /.-^ solution of poly-lT-dimethylaminoacenaphthylen in ethylene glycol monomethyl ether, applied thereto after the reeling up * The thus obtained photosensitive layers were 3 dried at 130 ⁰ C min to their moisture content to 4.0 $, whereby electrophotographic copying materials were produced Properties of copier materials of both groups As in Example 4, pen were compared with one another. The according to the invention

BATH

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. ICopier materials show an intense build-up of potential when electrically charged and at the same time a saturation potential that was about 1.5 times greater than that of the Comparison copy materials; their potential degradation oohwindiglceit when exposed was also about ten times larger than the comparative a copy materials.

If the auxiliary sensitizer solution and the photosensitive Layer-forming solution of this example mixed together and the total mixture for 24 hours was left to stand, the formation of gel-like precipitates could be observed. Hatchet, request, means this total mixture on a photosensitive layer to produce a sliver sheet occurred extraordinarily great difficulty. In addition, the comparative copying material produced here was so poor electrostatic properties that it was unsuitable for practical use.

Example 6

By dissolving 5.0 g of iodoform and 2.5 g of "Anqurd 12" (Trade name of one manufactured by the Irma Idon Armor Company surfactant) in 92.5 ΰ methanol The auxiliary senai "bilizer solution produced was in a

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Amount of 0.5 g / m 2 applied to the front side of carrier sheets made of polyester film, the rear side of which had been subjected to an electroconductivity treatment. After drying the auxiliary sensitizer at 90 ⁰ O for 1 minute, with a film thickness of Λτοη 4 * 5 / u a solution which formed a light-sensitive layer was obtained by adding 1 jO g of a 1.0% by weight methanolic brilliant green -Iiösung au 100 g 5.0 wt "~ $ strength was obtained LöBung of Eoly-N-dimethylformamide in a vinylnitrocarliaaol applied thereon after the reeling up. the photosensitive layer thus formed was for adjusting the! moisture content of 2 minutes at 120 ⁰ G dried in the dark to obtain electropliotographic copying materials. In addition, comparative copying materials were prepared by applying the same photosensitive layer-forming solution directly to the front side of similar support sheets not precoated with the auxiliary sensitizer and controlling their moisture content by drying.

The electrostatic properties of copy materials both groups were compared with one another as in Example 4. chen. Here, the copying materials according to the invention showed an about five times as large potential drop-off resistance with exposure like the comparative copy materials.

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In summary, the invention accordingly provides an electrophotographic copying material in the form of a carrier sheet, the back of which has been subjected to an electroconductivity treatment and the front of which is changed so that it was first impregnated with an auxiliary sensitizer or coated directly and then one on the auxiliary sensitizer light-sensitive ■ bzv; * pho ⁺ -c conductive layer with a photole'itktiveii organic substance was applied. Furthermore, the invention creates a Yerfalireii for the production of the aforementioned copying material, in which first an auxiliary sensitizer solution is applied to the front side of a carrier sheet, the back of which has already undergone an electroconductivity treatment, the applied auxiliary sensitizer is dried at 60-100 ⁰ G and finally a Light sensitive to light is formed on the auxiliary sonicator.

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Claims (8)

" ²¹ "'■ .T772511 P at ent a η s ρ r ü c h e 1 »Electrophotography ICopicrmaterial, characterized in that it consists of 'einoBL carrier sheet, - its The back is subjected to an electroconductive treatment vnirde and the front of which is provided with a coating containing an auxiliary sensitizer, and that there is a photoconductive one on this coating organic substance-containing, photosensitive layer is arranged. 2. copying material according to claim 1, characterized in that that the auxiliary sensitizer consists of at least one member of the series organic carboxylic acids, organic Sulphonic acids, metal halides, boron halides, quinones, aldehydes, ketones, ammonium, alkali metals or alkaline earth metal salts of inorganic and organic acids, organic nitro compounds, organic halides and inorganic acids. 3. copying material according to claim 1, characterized in that that the photoconductive organic substance from a VorLinduiy .; in the form of poly-IT-vinylcarbazole, poly-H- - 22 - 001111/97 »0 dimethyl amino ac enaphth ^ jlen, poly-lT-vinylnitrocarbazole, Poly-H-dimethylaminocarbazole, Polyvlnylaiithracen or Polyvinylnitronaphthalene is made. 4. copying material according to claim 1, characterized in that that the photosensitive layer also has a slight Contains amount of photosensitizing dye. 5. copying material according to claim 4, characterized in that that the light-sensitizing dye consists of at least one representative of the series B2. xtnin G, Rhodarain-B, ßhodamine S, methyl violet, ethyl violet, crystal violet, Methylene blue FZ, LIethylene blue BH cone, Victoria blue D, Brilliant green G-X, LIalachite green, Auramin G-cone, and Aeridinorange HS consists. 6. copying material according to claim 1, characterized in that the coating containing an auxiliary sensitizer also contains a compound in the form of a polyglycol or surfactant. 7. Process for the production of an electrophoto-praphiöchen Copy material according to one of the preceding claims, characterized in that sunlLchnb an auxiliary 009851/6770 Sensitizer-containing solution is applied to the front side of a carrier sheet, the back of which has been subjected to an electroconductivity treatment, then the applied solution is ^{dried at a temperature between 60 ° and 10O 0} G and finally a photoconductive oceanic substance containing a photoconductive oceanic substance to form a photosensitive layer solution is applied to the auxiliary sensitizer. 8. The method according to claim 7 »characterized in that v-as a solution of the auxiliary sensitizer in water, .Heth'anol or toluene is used. 009 851/0770 Blank page