CA1111697A - Light sensitive copying material containing a diazonium salt polycondensation product in a fish glue binder - Google Patents

Abstract

Abstract of the Disclosure This invention relates to an improvement in a tight-sensitive copying material the copying layer of which comprises a water-soluble, curable binder and a diazonium salt polycondensation product of recurr-ing units of the general types (A-N2X) and (B) which are linked to one another by intermediate members which have two bonds and are derived from a carbonyl compound capable of undergoing a condensation reac-tion wherein A is the radical of a compound which contains at least two isocyclic or heterocyclic aromatic rings and is able to undergo a con-densation reaction, at least at one point in the molecule, with formalde-hyde in an acid medium B is the radical of a compound which is free of diazonium groups and is able to undergo a condensation reaction, at least at one point in the molecule, with formaldehyde In an acid medium, and X is the union of an acid which forms a watsr-soluble salt with the con-densation product, the improvement being that fish glue Is the water-soluble, curable binder. The invention also relates to a process for the production of colored relief images.

Description

K - 2 '17 8 The invention relates to a negative-working light-sensitive copying material an.l a rnethod for processing this material to give colored relief images which c~an be used a~ a replacement for s;lver films or as colored images of any desired color shade. The copying material is composed of a transparent carrier and a light-curable, - water-soluble copying layer and is coated under aqueous conditions, developed under aqueous conditions, and the areas which have been exposed are stained with aqueous dyestuff solutions.
When producing original copies for the preparation of printing forms for offset printing, letterpress printing, screen printing and halftone gravure printing, a silver litho film is usually exposed, by means of a reproduction camera, to an original image or a paste-up and a halftone screen. After photographic developing, fixing and washing, silver films (soft dot films) which are used, or can be used, as the original copy are ob-tained. Frequently, however, this halftone original copy is recopied by con-tact copying to produce a silver hard dot film copy with reverse tonality, depending upon whether a positive or negative original cow is desired and whether the starting film was a conventional lithographic film or a silver duplicate (autoreversal) film.
In order to produce the recopied films or film assembly of the orlginal, at least the same amount of relatively expensive silver film material is again required. Added to this are the expenditure and the processing material for developing, usually in an expensive film de-veloping machine.
Transparent separation images, in the three primary colors and black, are produced using silver film ori~Jinal copies and, in the case of color separations, usually a set of four original copies, and these separation ima~JeS can be used as color test ~ilMs or as proof s~lbstitutes. Light-sensitive color films which are suitdble for this purpose are available with a positive-working or negative-workinfJ
layer which, in each case, is already stainecl to the corresponding color shade.
Positive-worlcing diazo materials for duplicating silver films are already employed in l:he graphics industry. These materials are diazotype material on pretr~ated polyester films and, on the areas which have not been exposed, azo dyestuffs which are opaque in the ultraviolet range are formed upon treatment with ammonia or aqueous solutions of amines or alkali metal salts by means of a couplin.g reac-tion. Films which can be developed under aqueous-alkaline condi-tions (DT-OS 1,572,085) also are lcnown as duplicating films and these carry a layer of o-naphthoquinone dia~.ide and colored substances which increase the photographic density to more than 1. On the same basis, positive color films with different staininy are know-n for mount-ing control and also as a. proof substitute (German Patent No.
1,291,197, andDT-OS 1,4~7,019).
The principle of using one copying layer for different applic.a-tions, such as color films of any desired color shade, also is already known, however, usin~ photopolymer layers and colored pi~ments (U, S . Patents Nos . 3, 06 0, 024 and 3, 0 6 0, 025) and al so by means oE
laminatin~ (DT-AS 2,004,21~). The suppression of the clyestuff ab-sorption capacity in the exposed and cross-linked parts of the layer also has been applied to other sys~tems which in themselves are negative-working and to staining with oil-soluble dyestuffs, in which case, thus, positive ima~es are formed (DT AS 2~o'lo~l36).
Several systems also already have been described for reversal films and for negativo color films. Attempts to reduce the disadvan-K ~ ~ 4 7 8 tages of silver Eilm, i.e., the hiyh price of silver an(:l the lack of transparenc~ in the visual regioll o~ the spectrum, are known. Thus, for ~xarnple, according to DT-OS 2,50~,445, ancl others, diazo com-pounds can be used in silver halic~/gelatin layers in orcler to form layers which are opaque to UV lic3ht but transparent to visible light.
Another process (DT-OS 1,772,146) uses the reaction of a photographic layer with reducincJ agents in order to produce colored images.
1ayers of rieyative-working systems, which are in themselves known and which can be used in a single layer or double layer to produce photomasks or colored fiLm images work completely without silver halide. Howeve~, photopolymer layers, which are appropriately stalned according to German Patent No. 1,171,267, do not yive the necessary high densit-~ values with acceptable exposure times. An attempt therefore has been made to overcome this disadvantage by separating the dyestuff and the photopolym2r layer (DT-OS 2,202,3~0), but this apparently is achieved at the expense of the resolution which can be obtained. Special photopolymer layers (DT-OS 2,360,350) can be pre-dyed with soluble or piyment dyestuffs or can be stained with substantive dyestufEs after copying.
Layers based on azido or diazo compounds make it possible to obtain hicJher resolution. It is known of azido compounds, and especi-ally o~ base-substituted azidoazomethines according to DT-OS
1,572 ,OG7, or azidodiphenylamirle derivatives accorcling to DT-OS

2,450,430, that they hecome intensely colored upon exposure. A
larye number of azido compounds which are in themselves known have been examined in more detail to determirle their useEulness for photo-masks and these compounds have been cklimed (DT-OS 2,~35,390).
Becausc of thc increasing maskiny upon exposure, howcver, ~ rcliable K-- 2 ~-~ 7 ~

copy can be obtained only with àiEEic ~ wiLh an accept~le e~<posure time and at densities of more than 2.
According to DT-OS 2,437,382, the use of triazoliurn or tetra-zolium salts and photo-rcducing agents and also, according to DT-OS
2,215,719, the coloring of vesicular film with pigments have been proposed as a further possibility for obtaining masking colored images.
With both processes, the transparency in the non-image areas appar-ently suffices only when the demands in respect of original copy material are relatively low.
Furthermore, it is known according to DT-AS 1,133,243,to use diazo resins in combination with color-pigmented covering layers or color-pigmented (DT-GM 7,316,607) and also, according to DT-OS
1,622,686, stained, p-benzoquinone diazide or p-henzoquinone imino-diazide layers for negative color films . Precoated copying material, which is stable upon storage, for the production of color proofing films according to DT-OS 2,032,~47, also has been desc:ribed, based on the diazo co-condensation products according to DT-OS 2,024,2'14, which are soluble in organic solverts.
Finally, in DT-OS 2,310,825, a llthographic material and pro-cess also ha~re been described in which a layer of gelatin of a certain type in combination with a diazodiphenylamine/formaldehyde conden-sation product (diazo resin) is stained with aqueous dyestuff solutions.
Furthcrmore, a light- sensitive copying composition for the pro-duction of screen printing stencils, which contains, as the light-sensiti~e compound,a condensation product of an aromAtic diaæonium compound, for e~ample a diphenylamine-4-d1azoniurn salt, and a spe^
cific compound capahle of undergoing a condensation reaction there-with, is described inDT-OS 2,0~1,395. This cornpound preEerahly - 1~116~9-7 K-~47~

has the seneral ~ormula E(-C~-IR -ORb) , wherein E clenotes the m-valent group oE a compound which is able to undergo a condensation reaetion with formaldehyde in an acid medium, Ra denotes H or an al~yl or aryl group, Rb denotes H or an alkyl, aeyl or phenyl group and m denotes an integer from 1 to 10.
The eondensation produet is in the form.of the salt of an ali-phatie monosulfonic aeid with 1 to 6 earbon ai.oms.
The eopying eomposition also contains a water-soluble, eur-able binder, preferably polyvinyl alcohol. In order that the steneil ean be better discerned, the composition also ean contain dyestuffs and pi!gments, but these are not present in a coneentration sueh that this results in a substantial increase in the photo~raphic density of the layer.
It is also known, from the book ":Die Lichtgerbung" ("Light ::
Tanning") by O. Watter, VEB Wilhelm Knapp Verlag, Halle (Saale), (195~), pa~e 105, to use light-eurable layers of bichromate and fish CJlue for block making, especially on eopper plates.
The object of the present invention is to provide a copying material whieh has a light-curable layer and in the cured state can be irreversibly stained to intense eolor shades with dyestuff solutions, espeeially those which have high absorption in the visible and actinie recJion oF the speetrum.
The invention is based upon a light-sensitive eopying material, the eopying layer of whieh is eomposed of a water-soluble, eurable binder and a dia~onium salt polyeonclensation produet of recurrincJ units of the general types (A-N2X) and (B), which are linked to one another by intermediate mernbers whieh have two boncls and are derived from a earbonyl compound capable o.E undercioing a condensation ~eaetion, , especially by methylene groups, wherein A is the radical o~ a com-pound which contains at least two isocyclic or heterocyclic aromatic rings and is able to undergo a condensation reaction, at least at one point in the molecule, with said carbonyl compound in an acid medium, B is the radical of a compound which is free from diazonium groups and is able to undergo a condensation reaction, at least at one point in its molecule, with said carbonyl compound in an acid medium, espe-cially the radical of an aromatic amine or a phenol, thiophenol, phenol ether, aromatic thioether or aromatic hydrocarbon or of an aromatic heterocyclic compound or of an organic acid amide and X is the anion of an acid which forms a water-soluble salt with the con- -densa~ion product, preferably the anion of an aliphatic monosulfonic acid ~ith 1 to ~ carbon atoms.
The symbol A is preferably the radical of a compound of the formula (Rl -R3-)pR2-N2X, in which X has the meaning indicated above, p denotes an integer from 1 to 3, preferably 1, Rl denotes an aromatic radical with at least one position capable of entering into a condensation reaction, R2 denotes a phenylene group which is unsubstituted or substituted by halogen atoms or carboxyl, sulfonyl, alkyl or alkoxy groups and R3 denotes a singIe bond or one of the groups:
-(CH2)~-NR4-0 (CH2r 4 S (C~12)r NR~

--O--K~2 ~ 7 8 -S- or -CO-NRa~-, in v~hieh q is a numl)er from 0 to 5, r is a number from 2 to 5, R4 is hydrogen, an al~yl group ~7ith 1 to 5 carbon atoms, an arallcyl group with 7 to 12 carbon atoms or an aryl group with 6 to 12 carbon atoms, and R5 is an arylene group with 6 to 12 carbon atoms.
The copying material according to the invention contains fish glue as the water-soluble, curable binder.
Furthermore, according to the invention a process for the pro-duetion of colored relief images is proposed in ~vhich a copying mater-ial of the eomposition indicated above is exposed, the regions oE the layer whieh have not been exposed are washed out with water, and the residual relief image is stained with an aqueous dyestuff solution.
Suitable dyestuEfs are, in particular, reactive dyestuffs, sub-stantive dyestufEs and acid dyestuEfs. Staining is advanta3eously earried out at temperatures in the range of 15 to 5UC. The concen-tration of the dyestuff solution preferably is 0.5 to 5% by vveight.
The diazonium salt condensation products used in the eopying material aecording to the invention are known. They are manufactured from the starting compouncls by a condensation reaction in a stron~ly acid medium, ~specially in concentrated sulfuric acid, orthophos-phoric acid or methanesulEonic acid. The starting eorrlpounds are either the dia~onium salt A-N2X, compound B and a carbonyl cornpound capable of undergoing a condensation reaction, especially formald.e-hyde, or, alternativelY, A-N2X and E(-CHRa-ORb) with the meaning explained initially. The manufacture is described in detail in U. S.
Pate~t llo 3,867,l~17.

, 6~ K ~ 2 ~ 7 ~3 Among the abovementioned condensatiotl products, those in which the un~ts B o~ E ~re derived from diphe~ thers, diphenyl sul-fides, diphenylrnethanes and diphenyls ar~ particula~ly preferred.
The anion X can be any anion which imparts solubility in ~Jater to the colldensation product. It is possible Lo use, for example, chlorides, brornides, sulfates, acid phosphates and the like. The anions of aliphatic monosulfonic acids with l to 6 carbon atoms, and especially methanesulfonate, are preferred.
In many respects, the copying materials according to the inven-tion are superior to the known materials of the same type which con-tain, instead of fish ~lue, ~vater-soluble synthetic polymers, such as polyvinyl alcohol, or polypeptides or proteins of natural origin, such as gelatin, casein or ~luten glue. They are distinguished by the fact that they can be cast from aqueous solutions at standard temperature, in contrast to the p'notogelatin layers, which must be cast warm, and by surprisingly ~ood adhesion, even on non-pretreated polyester films and glass as the carriers, gloss, high sensitivity to light and, at the same time, good stability upon storage and by the extreme ease with which they can be developed with water, coupled with outstanding developer resistance and, above all, by outstanding irreversible stain-ability with numerous dyestuffs. In princLple, all the reactive sub-stantive and acid dyestuffs which can be used for dyeing Eur, leather and wool can be used. Because of the good resistance, they also can be stained with acid and direct dyestuffs which are not adequately soluble in water but are soluble in water-miscible solvents. UV ab-sorbers also can be added to these solutions.
The stainability oE protein or polypeptide laycrs with suitable dyestuf~s already has loncJ been known as the pinatype process and tne 6~7 ~ 2a 78 greater stainab1lity of the parts oE the bichrom~te/c;el~ltin l~er which are less e~tensively cross--linl~(l, compared with mor(~ extensively exposed and cross-lirLked parts of the irnage, has been utilized for posi-tive continuous tone color images. The outstanding stainability of the copying materials according to the invention even in an extremely over-exposed and completely cross-lin'r~ed state is appare~tly related not orlly to the fact that fish qlue is more readily soluble and cross-linkable, compared with gelatin-, but also to the properties of the high molecular weight dia~o compouncls used.
The copying material according to the invention is composed of the carrier and the light-sensitive negative copying layer, which is stable upon storage and can be developed with water, applied to one side or, in some cases, to both sides of the carrier. Materials which can be used as carriers are the materials conventional for photographic layers and color film formulations, such as plastic films, but also special papers and cle2n, degreasecl glass plates. Dimensionally stable, biaxially stretched polyester films, preferably of glass-clear photoquality, are preferred. It was surprising that the layers according to the invention, which generally are 0.5 - 10 ~u thick, adhere well to these carriers without pretreatment and display cJood adhesion even upon developing. White-pigmented films, which are suitable as car-riers for color separation reflection images and continuous tone images, also can be used. Papers with a water-resistant coating and synthetic papers also can be used.
Although, when copying line images and screen imacJes, the image parts are in relief on the carrier film ~fter developing and act as an anti--Ne~wton laycr durincJ further copying, it is also possible aclvan--tageousi~y 'o use carriers with roucJllcr surfa:os ancl layer carners which 9 _ .

~` 3L~Lifi~3~ K-2478 have been pretreated on one sicie or both sides and provid~id ~vvith an anti-Netvton lacquer Iayer. Both normal biaxially stretched polyester films an;l polyester Eilms pretreated in the customary manner with tri-chloroacetic acid, and also cellulose ester lacquer layers with a total thickness of up to 10~ which are provided with silica or other piyments ean be used as the carrier film. In this case, when the exposed layer is stained, no fogging or background development takes place at the areas of the carrier surface which have not been exposed and are laicl open during developing. Because the provision of a substrate is neces~
sary only to roughen the surface and not to prornote adhesion, it prefer-ably is earried out only on the side of the carrier film opposite the eopying layer.
Other materials, for example polyvinyl chloride and cellulose acetate films and metal foils made of aluminum, anodized alurninum, eopper, ehromium and steel also ean be used as carriers.
The eopying layer is composed of a diazonium salt condensation produet (diazo co-condensate) and fish glue. The condensation prod-uets used here effect in the material a considerably greater sensitivil~y to light ancl stability on storage than do the condensation products of a diphenylamine diazonium salt and formaldehyde (diazo resins) whieh are otherwise conventional.
The amount of the diazo compound in the layer can vary con-siderably. In general, relatively less diazo co-condensate than diazo resin is required for a comparable cross-linking effect. The proportion of diazo co-condensate is cJenerally between 2 and a~0/c by weight of the solid constituents of the layer. The preferred ranc~e is between about 5 and 25% by weicJht.
- Layers of fish gl~l~ containing a diazo co-conclensate are cJen-erally at least 2 - 3 times more sensitive to light than layers of fish , ,s ~q~ ' K - 2 4 7 8 91u- containing the same amount of a dia~o resin The sensitivity to liyllt of corresponding l~-~yers is not substarltially changed by varyin~
the amount of diazo co-condensate. If it is desired to reduce the sen-sitivity to li~ht of such layers it is appropriate to replace up to 50% by weight of the diazo co-condensate by a diazo resin. A chloride-free and metal-salt free diazo resin according to DT-AS 1,289,7'11, is preferably used for this purpose. It is also possible to also use other negative~working light-sensitive compounds in addi~ion to the diazo co-condensate. By adding, for example, relatively small amounts of 4,4'-diazido-stilbene-2,2-disulEonic acid, the image areas already can l:)e stained yellow-brown by exposure. For the production of color films, however, the layer should con-tain only a diazo co-condensate.
The primary constituent of the copying layer of the copying ma-terial according to the invention is fish glue. According to clata given by the manufacturers, and in the litera-ture, the quality of fish glues is highly dependent upon the type of fish, the fish collayens used, the boiling conditions ard the purification. A feature common to all fish ylues is that, in contrast to gelatins obtained Erom mammals, they are readily soluble in water and these solutions are liquid at standard temperature, i.e., they have not yelled.
PreEerred grades of fish glue are those which are slightly turbid to pale y~llow and clcar and, in combinationwith bichromate, are cus-tomarily used as photocopyiny glues for the production of blocks, in which case the layers, after copying, must be render2d resistant to etchiny by bakiny (heat treatment). The fish glue from Norland Products Inc., New Brunswick, N. J., U.S.A., which is terrned Photoengraving Glue and is obtainable commercially as an approximately ~5% by weight aqueous non-gellill(J solution ~,vhich is as clear as gelalin and of con-stant quality and viscosity, is particuklrly preferred. The l'ayers' accorcling to the invention producecl with this gllle have ~JIossl/ cle~r surfaces ancl need not be h~ated after develop;ng. Nevf3rtheless, tlley have relatively good resistance to etching and ~ood stability on stor-age .
In order to vary the pro~erties such as the ease of development, the capacity for swelling, the layer thickness, the adhesion, the re-sistance to etching, and the ease with which the cured layer can be stripped by alkaline means, the layers of fish ~lue can be modifled by additives. In principle, all t'ne water-soluble synthetic and natural polymers can be added. Even polyvinyl alcohol displays only slight intolerance phenomena in amounts of up to about 10% by weight, rela-tive to the fish ylue. However, polypeptides and proteins of natural origin or polyvinyl compounds which contain carboxamicle groups are preferred and these can be added in amounts of up to about 80% by weight of the fish glue.
In order to slow down the developing process, which is usually very rapid, at the parts of the layer which have not been exposed, up to about 30 % by weight of gelatin and, with less success, smaller amounts of special caseins, polyacrylamides, and vinylacetate homo- and copolymer 20 dispersions can be added. The addition of polyvinyl pyrrolidone, its copolymerc and polyvinyl alkylacetamides is preferred for the modification of the layer of fish glue. If necessary, these water-soluble polymers can be dissolved more rapidly and to give a clearer solution by also using methanol, ethanol, or isopropanol, prior to adding the polymers to the fish glue solution.
Such solvents can be added to the coating solvent, namely water, in amounts of up to about 10% by weight without adverse effects.
In order to facilitate developiny and stainlny, salts, such as acetates, sulfates ancl phosphates, for ei~ample those o F sodium, potassium, macJnesium or aluminum, which at the same time can act 6~7 K -- 2 4 7 8 as bu~fers, and, in ad~ition, non-ioni.c an~l cationic wettiny acJ~nts and also biocidal agents can be added. Finally, it is also possible to disperse finely divided pigments such as silica (Aerosils), titanium dioxide, aluminum silicates or also polyvinyl acetate powder as fillers in an amount of up to about 40% by weiyht (relative to solids) in the coating solution. The coating solution generally should have a pH
value in the range of 2.5 to 7 and preferably of 2.5 to 5.
In order to enable an assessment to be made already during coating and exposure in respect to the thickness and exposure~ tirne of the layers which are to be stained only after developing, the layers, .
which in themselves are clear and slightly yellowish are already slightly stained red, for example with small amounts of Rhodamine 6 GDN extra (C.I. 45 ,160), blue, for example with Crystal Violet (C.I.
42 ,555~ or with copper phthalocyanine dispersion, or yeliow-bro~Arn, for example with 4, 4 '-diazostilbene-2, 2 ' -disulfonic acid, and/or, a s an incipient solution in ethanol/water, with the indicator dyestuffs bromocresol purple or bromophenol blue, in each case in an amount of up to 10% by wei~ht, relative to the àmount of cliazo compound.
The gradation of the layer also can be distinctly changed by means of additives. W absorbers enable a steeper gradation of the copy obtained with conventional layer-on-layer exposllre, at the ex-pense of the sensitivity to light, and at the same time act as a pro-tection a~ainst diffusion halation. The resolution can be further irn-proved by providing protection a~ainst reflected light halation and this is usually effected by a thin layer of dyestuff, for example water-~
soluble diamine brovvn M conccntrated (C.I. 22 ,311) on one of the two surfaces o~ the film. The UV absorbers are added in amounts such that, for an approximately 3~ thick layer, the characteristic density at 395 nm does not exceed a value of 1.0, becauso otherwise the R (t P~ n~ k , - 13 --~ .

' 2~17~

sensitivity to light no lonc~e~ rn~ets the requirernerlts in practice.
Water-miscible solvents also can be usecl to ~lissolve ~he UV absorb-ers ancl these r~main in homogeneous distribution after adclition to the coat`ing solLution.
It is more advantageous to retain the high sensitivity to light of the copying material according to the invention and to build up the d~sired photographic density and color after exposure and developing respectively. The utilization of chemical reactions in the layer offers one possibility for achieving this. Preierably, however, a treatment is carried out with dyestuff solutions which irreversibly stain the layers. The combination of the two methods and after-treatment of the stained layer are further possibilities for producing the final colored -image on the carrier.
The undecomposed diazo compound stilL present after optimum exposure, which is determined by means of a half-tone step wedge, can be used, for example, for a~o coupling. For this pur-pose, a coupling component in an alkaline medium is applied during or after developing. Phenylmethylpyra7olone or pheny!pyrazolone carboxylic acid are the most advantageous but the eifect is too slight for staining on its own.
Among the color-forming metal reagents, the formation of black lead sulfide from lead acetate, which is horrlogeneously distributed in the layer, and highly diluted hydrogen sulfide solution is best utili~ed.
This reaction can be carried out rapidly and in a manner which stren~-thens the layer, without undesirable odors. Maskincl by lead sulficle is spectrally aclvantageous over the entire UV and visible region and densities above 1.5 can be easlly obtained.
~taining with dyestuff solutlons offers thc greatest effect and the most diverse possibilities for building up the photographic density .

6~ k' -'~ 4 7 ~

or a coloratioll in the exposed and cross-linkecl parts o~ ths~ layer.
The material according to the invention is distinguishecl b~ the fact that layers of fish glue offer particularly good prerequisites for intense and durable staining coupled with good copying characteristics.
Although a certain hardening usually takes place even at the non-image areas when staining is carried out prior to developing, layers of fish glue nevertheless still can be developed rapidly. The reason for this and the advantage of layers oE fish glue is, apparently, that upon treatment with aqueous dyestuff solutions, the solubility of the non-exposed parts is not only substar-tially greater than in the case of other layers but also, conversely, the curing action by the dyestuff is relatively slight.
For these reasons, simultaneous developins and staining is possible with the fish glue/diazo co-condensate layers according to the invention. Nevertheless, it is preferred to carry out developing and staining separately in two working steps in order to avoid a change in the staining solution by enrichment with non-exposecl layer sub-stance, in order to obtain constant staining, especially in the case of color films.
Because of the high differentiation of the diazo co-condensate/
fish glu2 layers in readily soluble non-image areas and strongly cross-~ lced image regions which adhere to the carrier, developing with water is not critical, i.e., the layers have a high resistance to-developer .
Developing can be carriecl out by immersic)n in photographic dishes or cells, rinsing in a developing basin and wilshillg by spraying or automatically in commercially available apparatuses. These can be both continuous immersion apparatuses, such as are used for the developing of silver films, and continuous spray apparatuses, SUCil as ' .

~1-3L~ ~7 K -- 2 4 7 8 have been introduced for developing presensitized planoyraphic print-in~ plates. In spray appara~uses, the film to be developed is appro-priately fastened to a rigid plate, for exarrlple a used aluminum plano-graphic printing plate, and transported thereon. In order to achieve better wetting or cleaning of the surface, surface-active substances, salts or acids, for example cationic or non-ionic wetting agents, borax or phosphoric acid, o~tionally also can be added to the water used for deve loping ~
Automated developing is appropriately combined with autornated staining. The continuous immersion and spray apparatuses mentioned usually possess three (or more) chambers and are also suitable for aqueous dyestuff solutions. By varying the rate of throughput and the processing temperature, developing and staining can be well adjusted to one another and the conditions can be set to those most advantage-ous in practice. Under optimized conditions, such apparatuses re-producibly give constant original copy films and color films.
For special purposes, for example in cartography, the material according to the invention also can be processed stepwise in several layers. Thus, after taking the first copy and staining, for example black for names, the material is coated again, exposed, using another originàl copy, developed and stained with another color, Eor example blue for stretches of water. In order to represent contour lines, wood-land and the li~e, multi-color images on transparent or white carriers can be produced by repeated coating, exposure using the particular negative original copy and staining brown and then green, and the like.
In each case developing can be automated and stainlng appropriately can be carried out manually.
A multiplicity of clyestuffs frorn at least tllrce categories of dyestuffs which give irreversible dyeings, i.c., dyeirlgs which are --` 11;3.. ~L~,7 K- 2 4 7 8 substantially permanent and ~ast to wet pr.oce;,sing, can be used fc)r staining the exposed fish ~Jlue/diazo co-condensate layers. These dyestuffs are reactive dyestuffs, substantive dyestuffs and acid dye-stuffs and an intermediate classification is possible in the case of some dyestuffs. Surface-active a~ents and/or salts for buffering can . be added to the dyestuff solutions..
In the case of reactive dyestuffs it is assumed that under the most advantageous time/temperature/pH conditions for staining, which in each case are determin.ed empirical.ly, the dyestuff molecule is linked by a chemical bond to a protein molecule ~f the fish glue. In .
the case of substantive dyestuffs, on the other hand, it can be assum-ed that the mechanisms for the absorption on and adherence to proteins and polypeptides are like those for cellulose (Angewandte Chemie 75 (1963) 407-d~16). In the case of acid dyestuffs, salt formation with basic groups of the fish glue is probable and salt formation with une~posed diazo co-condensate is also known.
The following reactive, subsiantive and acid dyestuffs, which have a solubility in water, absorption characteristics, fastness to wet processing and density or color which makes them appear particularly suitable for film original copies which mask in the UV range or for color films and decorative films, have been found for the material and process according to the invention. The number of possible dyestuffs is not intended ,o be limitcd by this arbitrary selection. In addition, some dy~stuffs which can in themselves be used and are derived from intermecliate products which are known to be carcinogenic, for exam-ple ben~idine and 2- naphthylamine, have cle.liberately been excluded ' ~7 K - 2478 Reactive dyestlliEs Name Color Inde~ Name No.
Remazol Brilliant Orange RR: . Reactive Orange 7 Remàzol Brilliant Orange 3R: Reactive Orange 16 Remazol BrilliantOrange FR:
Remazol Golden Orange 4G:
Remazol Golden Orange 3G:
Remazol Yellow RTN: Reactive Yellow 24 Remazol Golden Yellow G: Reactive Yellow 17 i8,852 Remazol Red B: Reactive Red 22 Remazol Brilliant Red SBB: x) x) When no C.I. data are given, the dyestuff has not as yet been in-cluded in the 3rd edition (1971) of the Color Index.
Substantive dyestuffs Name Color Index Name No Rayon Fast Blaclc B : Direct Black 1035,255 hi~hly concentrated Coranil Direct Black F : Direct Black 3830,235 Diamine Fast Grey BN : Direct Black 5127,i20 Coranil Oran~e HE : Direct Oran~e 1719,160 Dianil Orange G : Direct Orange 1719,160 Diamine Fast Orange D : Direct Orange 1540,002 ,~Q,003 Diamine Orange BC extra : Direct Orange 1820,215 20,216 20,230 Congo Red : Direc t Rcd 2 ~322,120 DianilYellow 3 G : DirectYcllow 2213,925 Sirius I.ight Yellow R extra : Direct Yellow 50 29,025 Diamine T~ro~n M concentrated : Dircct PJrown 222,311 __ _ .

Dyestuffs Erom other categories which proved useful are:
Orasol Blac'~ B-A, B-V : Solvent Black 6 Zapon Fast Blac!c B, RE : Solvent BlC~Gk 34 12,195 Orasol Orange R~V-A, RW-V : Solvent Orange 10 Salicin Chromium Grey GL : Mordant Black 65 18,170 Erio Chromium Azurol BA : Mordant Blue 43,830 Alizarin Yellow GG : Mordant Yellow 1 14,025 Alizarin Yellow R : Mordant Orange 1 14,030 AlizarinYellow RS
Acid Dyestuff s Name ~ ~ No.
Benzyl Orange 2 R Acid Orange 45 22,195 Coranil Fast Orange RR Acid Orange 107 Supranol Orange GS Acid Orange 56 22,895 Brilliant Yellow 10,317 Coranil Yellow HE 3 G Acid Yellow 56 24,825 Fast Light Yellow G Acid Yellow 11:1 Fa st Light Yellow 3 G Acid Yellow 13 19,120 Fast Li~ht Yellow X Acid Yellow 55 19,040 Palatin Fast Yellow GRM Acid Yellow 99 13,900 Anthralan Red B concentrated Acid Red 42 17,070 Anthralan Red BBT Acid Red 81 68,200 Anthralan Red HGK Acid Red 288 Alphanol Fast Red R 23,635 Coranil Brown HEEG Acid Brown 104 Coranil Brown HEG~. Acid E3rowrl 105 33,530 Anthralan Blue B Acid Blue ~i1 62,130 Fullers Yellow H 3 G Schult~. Dyestuff Tables (7th 1'dition) No. 230 Poplin Yellow G Acid Yellow 9 13,015 Remalan Fast B.ack G Acid Black 138 ~. .

- 19 - .

111~6~ 2 ~L 7 8 Special ~hades ancl, thus, sp~cial eff~cts (clecorative colors for graphic use), can be achieved urlder comparable CGnClitiOIIS usins the dyestuffs listed below: .
Namè Color Index Name No.
-Yellow: Remaderm Yellow HPR Acid Yellow 36 Remaderm Yellow H 5 G ---Remaderm Yellow HR ---Capracyl Yellow NW Acid Yellow 51 Pinatype Yellow D, F ,R ---Orange: Pinatype Orange ---Nubilon Orange R Acid Orange 7 Red: Alphanol Fast Brilliant Red BL ---Amidorhodamine B concentrated Acid Red 52 I,anaperl Red G --- 22,2~5 Nubilon Red RR ---Remaderm Red HPB ---Remazol Brilliant Red FB Reactive Red 104 Remazol Brilliant Red BB Reactive Red 21 Remazol Brilliant Red GG Reactive Red 106 Remazol Brilliant Red SBB ---Rema201 Brilliant Red F 3 B, 6 B
Remazol Ruby GR ---Red: Ponceau RR Acid Red 26:1 16,151 16 ,150 Ponceau Red 6 16,290 Ponceau Red 6 R
Blue: Duasyn Acid Blue SN :~cid Blue 93:1 Nubilon Blue BS ---Remaderm blue -IB~Direct Blue 199 Duasyn Direct Violet BDirect Vlolct 9 Green: Duasyn Acid Green V Type 8005 Acid Green 16 -- ~ o --L65~7 K - ~ ~ 7 8 The copyiilg material can be stainecl even during co~ting using such dyestuffs in low concentration. This is advisable only wnen the loss in sensitivity to light which is associated therewith is unimpor-tant. In such cases the adtlition of UV absorbers to the layer is to be preferred and the gradation can be more effectively made steeper by - this means.
Benzophenone derivatives which have a solubility in water of more than 5%, for example Cyasorb W 284 and Uvinul MS 40 and DS
~C .
49, can be used as W absorbers. Cyasorb UV 2DI and Cyasorb UV 12, which are less soluble, possess good and long-wave absorption even at a low dosa~e. Further UV absorbers which can be used are describ-ed in Karsten, "Lackrohstoff-Tabellen" ("Lacquer Raw Material Ta~les"?, 5th Edition, pages 440-441.
An additional possibility for use of the material according to the invention which has been described above is the production of continuous tone images. While the layer acquires a high density gradient (steep gradation), as a complement to the masking effect of the unexposed diazo compound, when W absorbers and/or masking dyestuffs are add-ed, on normal exposure directed to the layer side, the effect on expo-sure from the rear side is precisely the reverse. The light coming through the carrier film then cures the layer most strongly in the side of the layer which adjoins the carrier film and least in the surface of the layer ~,vhich faces away from the carrier ~ilm. Even with a relatively short exposure to a continuous tone wedge from the side of the clear or translucent carrier film, it can be clearly seen that the layer becomes thinner, as a result of developing, at the less exposed areas and is correspondin~ly less intensely colored at these areas upon staining.
With this procedure, the CopyinCJ layer possesses a gentle gradation, which is the gentler the higher the content of the W absorber.

-- 21 -- , ' L~7 K- 2 ~ 7 ~

While the negative-workiny copying layer is customarily used for the reversal of line and screen objects, it can be used for recopyiny continuous tone images using the variant described . It is immaterial whether exposure to a positive continuous tone original copy is through the rear side and a negative continuous tone image is formed after the developing and stainin~ or vice versa. The dyestuffs mentioned also can be used for this procedure. Thus, continuous tone color images, ~or example continuous tone color separations, also can be produced.
When the layers are used for continuous tone work, it is advantageous not only to add UV absorbers, but also to make the layers somewhat thicker, layer thicknesses of about 4 - 8 ~ being preferred . View-through continuous tone images are obtained when a transparent film is used and continuous tone reflection images are obtained on an opaque white carrier.
In most cases, the some~vhat longer exposure time and the loss in sharpness caused by light scattering in the opaque film and the pig-mented layer which may be present, compared with a transparent carrier film, can be accepted. When the halftone image is stained with a dye-stuff ~IYhich mas}~s UV light, additional copies can be made analogousl~r using this image, so that, for example, the continuous tone positive drawn ~0 from a continuous tone negative can be compared with the original continuous tone positive in respect of gradation and extent of tonality. It is possible to optimize the layer formulation for the desired application by means of such generation copies.
Finally, a further possibility and arl advantage of this copying material which is inexpensive and, in respect of proceclure and color, can be processed to diverse end products, is that the colored effluents can be purified b~ the processor, even thoucJh they are already free from toxic substances. For this purpose, commercially available flocculat-ing a~ents based on polyacrylamide or carhoxymethylcellulose are added 2~

to these ~IyestuEf solutions or to (Iyestuff solutions which are exhaus~ed or have not been consumed. In order to impro~e separation and to bring the dyestufEs into a form inwhich they can be be~ter filtered, it is in many cases advantageous first to add metal salt solutions, which can precipitate the dyestufE as a colloid, and to use ca~ionically modified polyacrylamides. The most advantageo~ls data i,n respect of procedure, type, concentration ancl other sedimentation and clarification condi-tions must be determined in each case.
The examples which follow further illustrate embodiments oE the invention. All the percentage figures and quantity ratios are to be understood as units by weight unless otherwise stated. The layer thicl;nesses were measured in the dry state.
Example 1 5 g of the dia~o co-condensate of 2 moles of 3~methoxy-diphenyL-amine-4-diazonium sulfate and 1 mole of 4,4'-bis-methoxymethyl-diphenyl ether, isolated as the methanesulfonate, ~0 g of fish glue (Special Photoengraving Glue from Messrs. O. Ring, 2 Hamburg 11, with a solids content of approximately 50%) and 0.2 g of Rhodamine 6 GDN
extra (C..I. ~15,160) are dissolved in 500 ml of water and a biaxially stretched 75~ thick polyester film is provided with an approximately 4 thick coatin~ (dry thickness) using this solution.
The copying layer is exposed under a negative test original copy for 50 seconds using a 5 KW metal halide lamp with a MO 23 Sylvania burner at a distance o~ 14~ cm, and then developed by rins-ing the areas which have not been exposed for at most 1 minute with tap water and stained intense bklck by immersion of the exposed areas, in the course of 3 minutes, at 30C, in a 5% solution of Coranil Direct Black B (C.I. Direct Black 19). ~ density of 2.2 was measured at 395 nm with a photovolt densitometer using the f-lter combination consist~
ing of UG 3/2 mm, 13G 12/2 mm, KG 1/2 mm and GG 337/2 mm from , ~ lr K--2478 Messrs . Schott, TmaX= 54%, HW 57 nrn .
Accordinyly, when this positive test image is used as th~3 photo-~raphic original copy in place of a corresponding silver filr~ oriyinal copy`for copying commercially available presensitized posi~ive printing plates which contain o-naphthoquinone diazide sulfonic acid esters as the light-sensitive substance, a clean image of the original copy on the printing plate can be obtained even with exposure 10 times the normal, i.e., the stained parts of the layer of the film provide more than the necessary masking.
DyestuEf solution which is exhausted or no longer required can be purified from the intensely coloring dyestuff by flocculation. For this purpose, a metal salt solution, such as aluminum sulfate or ferric chloride, is added and the metal salt of the dyestuEf is converted into a form in which it can be filtered by ad~ing a polyacrylamide flocculat-ing agent, for example a 0.2% solution of a polyacrylamide having a molecular weight of 1-2 1 o6 Example 2 10 g of the diazo co-condensate of 1 mole of 3-methoxy-diphenylamine-4-diazonium sulfate and 1 mole of 1 ,3-dihyclroxymethyl-4,6-diisopropyl-benzene, isolated as the methane sulfonate, 100 g o~
aqueous fish glue solution (Photoengraving Glue from Norland Products Inc., New Brunswick, N. J., USA, with an approximately ~5% solids content and of approximately 6,000 cP?, 2 g of magnesium sulfate -7~12O an~ 0.2 g of a non-ionic wetting agent (polyoxyethylene nonyl-phenyl ether) are dissolved in 500 ml of water.
1`~ 50~ thick biaxially stretched polyester film of photographic quality, which has been pretreated on both sides with trichloroacetic acid in ordcr to improve the surface against the formation of Newton rings on exposure, and has been matted with a layer of c~llulose - 2~ -L.697 K- 2 a 7 8 - acetate-propionate, to ~J'nich a conventional il-ip agent has bec~n adcled, is coated with this solution.
Copying thereon and staining with an aqueous solution of Pop-linYellow G (C.I. 13,015) cJives a clean yellow image on a fog-free background and can be used for further copying.
Exam~le 3 ~ I g of the diazo co-eondensate of 1 mole of 3-methoxy-diphenyl-amine-4-diazonium sulfate and L mole of 4/4'-bismethoxymethyl-diphenyl ether, isolated as the methane sulfonate, and 100 g of a fish glue as in Example 2 are dissolved in 500 ml of water and four films are eoated with this solution, with a layer weight of about 2.0 g/m in eaeh ease. One earrier film is eomposed of a polyester film (187.5y~thiek) whieh has been colored white and the three other films eonsist of 100y~ thiek`transparent polyester films.
In order to eheck the montage for eolor separations, the eoated films are eaeh exposed for ~5 seeor.ds under the four sereened silver film eolor separations under a 5 KW COP XP 5000 xenon point licJht eopying lamp from Messrs. Staub, Neu-Isenburg, at a distanee of 140 em, the blue separation being produced on the white earrier. Then, all four films are cleveloped by immersing for about 1 minute in a water-filled eell and, for staining, the films are eaeh immersed for about 3 minutes in cells containing the following solutions:
1.5Y~ of Remaderm Blue HBL C.I. Direct Blue 199 ~1 % of Remazol GoldenYellow G C,I. 18,852

3 % of Rema~.ol Brilliant Red SBB ----

4 % of Coranil Direet Blaek F C,I. 30,235 After rinsing with water, the four color separation films are driecl. A reflection copy similar to the proof is obtained by laying the films on top of one another in accordanee Witil the printing sequence.

.

If the blue separation is also produced on a transparent filrn, the sarne image is obtained as a transparency.
Exam~le 4 8 g of the diazo co-condensate of 1 mole of 2,4',5-triethoxy-diphenyl-4-diazonium salt and 1 mole oE 4,4'-bis-methoxymethyl-diphenyl ether, isolated as the methane sulfonate, 54 g of a fish glue as in Example 2, 12 g of partially saponified polyvinyl alcohol of med~
ium viscosity (Mowiol 26-88) and 1 g of a commercially availal~le biocidal agent (Merga~AF, Riedel de Haen), the main constituent and active compound of which is chloracetamide, are dissolved in 400 ml of water.
This formulation was compared with a corresponding layer con-taining only fish glue and the diazo compound, in each case after apply-ing a layer thickness of about 4~ to a polyester film, stepwise ~xposure for 50~150 seconds using a 5 KW MH lamp under a 60-screen and 120-screen and a 13-step continuous tone test wedge,developing with a spray and staining with an aqueous dyestuff solution containing 1/2 of Congo Red ~C.I. 22 ,120) and 1% of Diamine Fast Gray l~N (C.I. 27,720).
Clear differences are apparent even upon developing. The non-uniform PVA-containing layer cannot be developed cleanly even when it is wiped over; the limit of developability i5 at about 10/~, of PVA, rela-tive to the fish glue. The pure fish glue layer is rapidly and cleanly open upon rinsing with or immersing in water.
On staining, the red-brown color is pale and uneven in the case of the PV~-containing layer. Staining is better and more intense with clean light and deep points, even in the 120~screen, in the case of the pure fish glue layer. After immersing for 3 minutes at 30C, a density of 2.8 was measured at 395 nm. The extinction curve shows a density of at least 2.8 in the spectral region from 300-550 nm. This layer also -I R ~ p ~

L6i~ K- 2 ~17 8 displays the same UV masking af~er ~reatrnent with an acid aqueous solution, for e~ample 3% phosp~loric acid. As a result of the indicator action of Congo Red, the red-brown image points are reversibly re-d~ed black during this treatment. Using an original copy of this type, commercially available negative planographic printing plates with diazo -layers and a commercially available photopolymer planographic printing plate were each exposed for up to 8 times the normal exposure time.
Non-scumming printing plates were obtained.

.
Exam~le 5 2 g oi the diazo compound indicated ln Example 1, 40 g of fish glue as in Example 2, 5 g of Rovita FN 4 (digested milk protein (casein) from Rovita GmbE~, Aschau bei Kraiburg) and 0.1 g of Crystal Violet (C .I . ~12 ,555) are dissolved in 200 ml of water.
A 180}~ thick polyester film is coated with this solution, exposed and stained intense black in the course oE 3 minutes using a 2% metha-nolic solution of Orasol Black BA (C.I. Solvent ~laclc 6).
The addition of casein makes the layer somewhat harder and ren-ders it slower to develop. Staining from an alcoholic solution instead of from an aqueous dyestuff solution is possible without attack to the layer but is indicated only if no corresponding aqueous dyestuff solution is available.
ExamDle 6 2 g of the diazo co-condensate as in Example 3, 40 g of fish glue as in Example 2 and 0.5 g of aluminum sulfate 18H20 are dis-solved in 200 ml of water and a 50~ thick biaxially stretched polyester film is coated in a thickness of about 5~ with this solution.
After exposure in the customary manner, also using continuous tone and screen test step wedges so that step 3 of a 13-step continuous tone .

L6~7 K~ ~ 7 8 test wedge remains covered, developing and staining are c~ried out automa~:ically after one another in a continuous immersion appara-tus. For this purpose, water is filled into chamber 1 of the Durst RCP
20 bench contlnuous apparatus (9 cm/minute) and an aqueous dyestuff solution of 1.5% of AlizarinYellow R (C.I, 1'1,030) and 1.5% of Alizarin Yellow RS (C .I . Mordant Orange 15) are filled into chamber 3 and the thermostat of the apparatus is set to 30C. If developing is carried out manually by immersion in a dish or cell containing water, staining can be carried out in chamber 1 and rinsing in chambers 2 and 3, Using this apparatus, which was designed for developing silver images, the diazo copying layers described here also can be processed continuously and with reproducible results. Excess dyestuff solution is squeezed off at the` end of the apparatus by rubber rollers . The con-centration of the dyestl~ff solution can be checked photometrically and, if necessary, made up by adding concentrated dyestuf~ solution. The intensely yellow-colored films also can be rinsed for a prolonged period or collected in a washing basin without any noticeable drop in density occurring with this layer which is resistant to wet processing, i.e., it does not bleed.
The resulting filrns can be used for copying positive and nega-tive copying layers which are sensitive to UV li~ht. Compared with silver film original copies, they have the advantage that, because of their visual transparency, registration can be effected easily in the case of monta~es and in the case of bored clrcuit boards. Similar re-sults are obtained when a mixture of 1% of Brilliant Yellow (C .l, 10,317) and 2% of PaLatin Fast Yellow GRN (C,I. 13,900) is used as the dyeing solution.

L697 K - 2 4 7 ~3 Fxample 7 60 g of a fish glue as in Exampl~ 1, 20 g of a diazo co-condensate as in Example 3, 20 g of -vinyl pyrrolidone,t'butene copolymer solution ~approximately 40% solution in isopropanolj, 1 g of lead ace-tate trihydrate and 2 g of 7-diethylamino-4-methyl-coumarin are dis-solved in 500 ml of water and a 50~ thick polyester film which has been colored white is coated in a thickness of about 5 g/m2 with this solution .
The film is exposed for 3 minutes under a negative line original copy using the Printaphot tube exposure apparatus from Fotoclark,fixed to an aluminum plate in a spray developing apparatus, developed with water which is cycled by pumping and treated, in a second chamber, with 0.1% NaSH solution. By this means, a brown-black PbS precipi-tate is produced imagewise in the layer. This has a density of 1.3 with a base density of the film of about 0.2.
If the same mate,ial is exposed through the white film for 2 minutes under a negative continuous tone transparency and developed, and blackened, in the same way, a gray-black positive continuous tone image is formed.
In order to deepen the black and the density to above 2.5, the two images are immersed in a 3% solution oE Remalan Fast Black C~
(C.I. Acid Black 138) for 2 minutes at 40C, rinsed and dried. The action of thc two color-forming solutions also can be combined but this brings no advantages; staining solely by means of a dyestuff solution is to bo preferred.
Example 8 10 g of the diazo co-condensate of Example 3, 60 g of a fish glue as in ~xample 2 and 20 g of polslvinyl methylacetamide are dissolv-ed in 500 ml of water and 30 c~ of finely ground titanium dioxide are dispersed in the solution.

- 29 -- ' .

L6~ 7 K - ~ ~ 7 ~3 Using this solution, a 100~ thick, bi~ially stretched polyester film is coated in a thickness of about 10~,. This copying m~terial is exposed ior 150 seconds under a negative original copy using a 5 KW
~IH lamp at a ~istance o~ 1~0 cm and the parts of the layer which have not been exposed are removed in the course of 1-2 minutes by spraying with ~vater.
This cJives a white image on a transparent carrier which is par-ticularly suitable ior the production of lettering, tables, diagrams and drawings, for example by means of an episcope or of overhead projec-10` tors. Being a reflection image, this material can be yet further modified for di~erent applications, for example by subsequently writing on the white surface with a mar~ing pencil or drawing ink or by scratching in symbols. In addition, the white material can be stained as desired in various color shades, depending upon the part of the subject, for e~am-ple for cartographic purposes. Depending upon the desired depth of color, 0.5% to 5% aqueous solutions of the following dyestufis have proved useful: -blue D ua syn Acid E~lue S N (C . I . Acid B I le 9 3 :1 ) Duasyn Acid Direct Violet B (C.I. Direct Violet 9) green DuasynAcid Green V, Type 8C05 (C.I. Acid Green 16) yeliow Remaderm Yellow HPR (C.I. Acid Yellow 36) Pinatype Yello~J F
oran~e Nubilon Orange R (C.I. Acid Orange 7) red Ponceau Red 6 R (C.I. 16,290) Lanaperl Red G (C.I. 22,245) blacl~ Remaderm Black MKN
Amido Blacl~ HTT
These layers also can be processed analo~Joi~sly on ~lass as the carrier, instead of on p~lyester filrn, because cJooci adhesion is achieved ?7 K- % 4 7 ~

by the fis'n ~lue. In a~ldition, op~que wilite films, for exarnple a white-pigm3nted plasticized PVC film, or mechanically roughened aluminum are also suitable as carriers. The carrier surface and the dyestuff are to be so suited that the carrier does not take up any color at the non-image areas.
Example 9 8 g of the diazo co-condensate as in Example 1, 90 g of a fish glue as in Example 2, 15 g oE polyvinyl pyrrolidone ancl 4 g of Cyasor~
UV 284 benzophenone derivative, previously dissolved in 50 ml oE
ethanol, are dissolved in 450 ml of water and a 80~ thick softened cellulose acetate film is coated in a thickness of about 6 ~l~usiny this solution .
The layer is exposed through the acetate film for 2 minutes to halftone negatives from an amateur silver filrn in a commercially avail-able contact copying apparatus. Then, the layer is developed by rins- -ing with water for 1 minute and stained in a 3% aqueous solution of Salicin Chromium Gray GL (C.I. 18,170) for 2 minutes.
This gives gray-black positive continuous tone view-through images, for example black-and-white transparencles from miniature negatives.
When an opaque white film is used as the carrier, positive reflection images of miniature films are obtained analogously and these can l~e used in place of positive silver paper image contact copies to assess the negatives.
With normal exposure, i.e., layer on layer with line or screen negatives, and conventional developln~ and staining, a clean positive _ of the original copy is obtained from the laye~, which is hard in use.
Example 1 0 6 c; of the diazo co-conclensatc ;r-~m Example 3, 100 cJ of a fish glue as in Example 2 and 1 g of l\/qsSO~L 7H20 are dissvlved in 500 ml of water.

K- 2 ~ 78 Using this solution, a 50~ thic} polyester fllm is coatecl on a spin coater to a thickness of about 2~1~. It is exposed under the black separation (depth) of a negative four-color set under a 5 KW MH lamp at a distance of 140 cm for 15 seconds, then developed in the course of lQ seconds by rinsing with water and stained by immersing in a 3%
aqueous solution of Diamine Fast Gray BN (C.I. 27,720) at room tem-perature for 3 minutes, rinsed wlth water and dried. Using the same coating solution, a further three coatings are then produced analogously, exposed using the particular original copy, developed and stained with one of the following aqueous dyestuff solutions: blue with 2% of Water Blue TBA (C.I. 42,755), red with 1% of Amidorhodamine B (Acid Red 52) or 2% of Lanaperl Red G (C,I. 22,245) and yellow with 1.5% of Alizarln Yellow GG (CoI~ 14,025) or 1.5% of Sirius LightYellow R extra (C.I.
29,025) . The particular parts of the image stained previously are not impaired by the repeated operations and are not further changed by the subsequent different colbr.
A transparent image of the four-color subject which, when viewed on a white substrate, is similar to the proof, is obtained.
At Icast 30 lines/mm are resolved in the test original copy which is also copied. Another test original copy which is also copied displays clean deep and light parts in all four colors in a 60-screen and 120-screen. The four dyestuffs do not bleed during the multiple treat-ment with water. This is ascribed to the good absorption of the dyestuffs on the fish glue and the precipitation of the dyestuff salt with incom-pletely exposed diazo polycondensate at the image areas, which precipi-tation can be detected even in a test tube experiment.
Example 11 In order to show the superiority of the fish cJlue layer according to the invention over the closest state of the art (DT-OS 2,3io,825), the following layers were colnpared with one another:

A. Fish ~31ue layer prepared as follows.
40 g of a fish glue as in E:~ample 2, 2 g of a diazo co-conàensate according to Example 3, 0.1 g of MgSO4 7H2O, 0.1 g of Rhodamine 6 GDN e~tra (C.I. 45,160), and 0.05 g of a non-ionic wetting agent as in Example 2 are dissolved in 200 ml oE H O.
E~. G~latin layer (analogous to Example 6, DT-OS 2,310,825):
The pH value of 100 ml of a 10% aqueous solution of a gelatin from Messrs. Scheidemandel AG with an isoelectric point of 8.5, a pH
value of 4.4 and a gel strength of 272 Bloom, was adjusted to 7.0 with triethanolamine. 6 ml of a 2.5% a~ueous solution of the condensation pro~uct o~ p-diazodiphenylamine and formaldehyde are added to this solution and the rnixture is kept at 50C.
C. Polyvinyl alcohol layer of the following formulation:
8 g of partially saponified PVA of medium viscosity (Moviol 26-88), 1 9 of a diazo co-condensate according to Example 3, 0.1 g of Rhodamine 6 GDN extra and 0 . 05 g of the wetting agent as in A are dissolved in 200 ml of H2O.
All three solutions were applied to polyester ~ilms in the same layer thiclcness t2,~ when dry) and dried. For coating, solution B must be warmed to 50C, in contrast to solutions A and C.
The 20" exposure was eEfected using a 5 KW MH lamp at a dis-tance of 140 cm for all layers under the same conditions.
The fish glue layer and gelatin layer were stained with a 3%
aqueous solution of Benzo Deep Black E extra (C.I. 30,235) within 10"
at 50 C. After rinsing with water, the following densities were _ measured:
Filter combination 3~)5 nm Wratten 93 Fish glue 1.7 2.0 1.6 - 1.7 C~clatin 1.2 - 1.5 1.0- 1.1 ~" K-2478 The sensitivity to light of layer A was found to be 100 % better than that of layer B for the conti,~uous tone step wedge which was also copied.
The preferred processing method for the layer o fish glue (A) according to the invention, i.e., first developing and then staining, cannot be used for gelatin layers because these layers cannot be de-veloped wlth cold water before staining.
Staining for 3 minutes at room temperature in the above-mentioned dyestuff solutions, after developing, gives the foLlowing - densities for layer A:
Filter combination 395 nm Wratten 93_ 2.~ - 2.6 2.1 - _ When the stainabili-ty of the three layers with the dyestuff which is preferrecl for fish glue formulations, i.e., Coranil Direct Black B (C.I. Direct Black ;9), is compared, the following density values are obtained for staining before cleveloping in 5% aqueous solution at 50 C for 10":
Filter Combination 395 nm Wratten 93 Fish glue 2.0 ~ 2.2 2.1 - 2.6 Gelatin 1.6 - 1.7 1.9 - 2.1 - PVA 1.0 - 1.1 _ 0.9 - 1.0 Staining for 3 minutes at room temperature with 5% Coranil Direct Black B after developing is possible only in the case of fish glue and PVA and leads to the following densities:
Filter Combination 3 95 nm Wratten 9 -Fish glue 1.8 - 2.0 1.9 - 2.0 PVA 1.1 - 1 a, 1.2 - 1 3 If layers stained with Benzo Deep Black E extra are immersed in H20 for a "rolon~ed period and the reduction in the clensity is then , 169~ K~ 2 ~ 7 measured, the clecrease in the density is about 20% for fish glue an~
about 40% for ~elatin.
The resolution oE all three layers is virtually equally good.
It will be obvious to those sl~illed in the art that rnany modifi-cations may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications .

Claims (17)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. In a light-sensitive copying material, the copying layer of which comprises a water-soluble, curable binder and a diazonium salt polycondensa-tion product of recurring units of the general types (A-N2X) and (B) which are linked to one another by intermediate members which have two bonds and are derived from a carbonyl compound capable of undergoing a condensation reaction, wherein A is the radical of a compound which contains at least two isocyclic or heterocyclic aromatic rings and is able to undergo a condensation reaction, at least at one point in the molecule, with said carbonyl compound in an acid medium, B is the radical of a compound which is free of diazonium groups and is able to undergo a condensation reaction, at least at one point in the molecule, with said carbonyl compound in an acid medium, and X is the anion of an acid which forms a water-soluble salt with the condensation product, the improvement that fish glue is the water-soluble, curable binder.

2. Copying material according to claim 1 wherein said carbonyl compound is formaldehyde.

3. Copying material according to claims 1 or 2 which contains a diazon-ium salt polycondensation product in which B is the radical of an aromatic amine or of a phenol, thiophenol, phenol ether, aromatic thioether or aromatic hydrocarbon or of an aromatic heterocyclic compound or of an organic acid amide .

4. Copying material according to claims 1 or 2 which contains a diazon-ium salt polycondensation product in which A is the radical of a compound of the formula (Rl-R3-)pR2-N2X

wherein X denotes the anion of an acid which forms a water-soluble salt with the condensation product, p denotes an integer from 1 to 3, Rl denotes an aromatic radical with at least one position capable of entering into a condensation reaction, R2 denotes a phenylene group which is unsubstituted or substituted by halogen atoms or carboxyl, sulfonyl, alkyl or alkoxy groups, and R3 denotes a single bond or one of the groups:
-(CH2)q-NR4--O-(CH2)r-NR4--S-(CH2)r-NR4--S-(CH2)r-NR4--O--S- or -CO-NR4-, in which q is a number from 0 to 5, r is a number 2 to 5, R4 is hydrogen, an alkyl group with 1 to 5 carbon atoms, an aralkyl group with 7 to 12 carbon atoms or an aryl group with 6 to 12 carbon atoms, and R5 is an arylene group with 6 to 12 carbon atoms.

5. Copying material according to claims l or 2 which contains a diazon-ium salt condensation product in which X is the anion of an aliphatic mono-sulfonic acid with 1 to 6 carbon atoms.

6. Copying material according to claims 1 or 2 in which the fish glue has an average molecular weight of less than 60,000 and is soluble in water with the formation of a clear solution which does not gel above 10°C.

7. Copying material according to claims 1 or 2 which additionally con-tains up to 40% by weight, relative to fish glue, of other water-soluble, polymeric organic compounds.

8. Copying material according to claims 1 or 2 in which the copying layer contains 2 - 40% by weight of a diazonium salt polycondensation product.

9. Copying material according to claims 1 or 2 which contains, as the layer carrier, a transparent plastic film.

10. A process for the production of a colored relief image, comprising exposing a copying material according to claim 1 to light, washing out with water the regions of the layer which have not been exposed and staining the residual relief image with an aqueous dyestuff solution.

11. A process according to claim 10 wherein said carbonyl compound is formaldehyde.

12. A process according to claims 10 or 11 in which the dyestuff used for staining is a reactive dyestuff.

13. A process according to claims 10 or 11 in which the dyestuff used for staining is a substantive dyestuff.

14. A process according to claims 10 or 11 in which the dyestuff used for staining is an acid dyestuff.

15. A process according to claims 10 or 11 in which staining is carried out with a 0.5 - 5% by weight dyestuff solution.

16. A process according to claims 10 or 11 in which the dyestuff is opaque in the W region of the spectrum but is transparent for visible light.

17. A process according to claims 10 or 11 including using a copying material with a transparent layer carrier film and exposing said material from the back through the carrier film under a continuous tone original copy.