US3547637A - Light-sensitive diazotype material - Google Patents

Description

United States Patent Oifice 3,547,637 LIGHT-SENSITIVE DIAZOTYPE MATERIAL Siegfried Scheler, Wiesbaden-Schierstein, Johannes Munder, Wiesbaden-Biebrich, and Arno Brauninger, Wiesbaden, Germany, assignors, by mesne assignments, to Keutfel & Esser Company, Morristown, NJ.

No Drawing. Filed July 3, 1967, Ser. No. 650,607 Claims priority, application Germany, July 6, 1966, K 59,674, K 59,675 Int. Cl. G03c 11/54, 5/34, 5/18 US. Cl. 96-49 Claims ABSTRACT OF THE DISCLOSURE A diazonium compound of improved light-sensitivity and coupling potential useful in the preparation of acid-, alkaline-, and neutral-developing one-component diazotype compositions has the general formula comprises a polarizable double bond in the immediate vicinity of the nitrogen atom. With neutral and acid developer compositions comprising a wide variety of known azo coupler components these compounds rapidly form stable, non-bleeding azo dyes, and with alkaline developer compositions comprising 2,3-dihydroxy naphthalene and 2-hydroxy-3-naphthoic acid amide azo coupler components, commonly employed for blue dye formation, form red azo dyes.

BACKGROUND OF THE INVENTION The present invention provides an improved light-sensitive diazonium compound useful in diazotype material which, after image-wise exposure to light under a transparent original and subsequent development with known neutral or weakly acid developer solutions containing phloroglucinol or the like, rapidly yields copies with redbrown to violet-brown azo dye images.

Development of one-component material with neutral to acid developers instead of the otherwise usual alkaline developers has the advantage that the acid developers have a substantially better stability than alkaline developers. In a developing device, an acid developer solution thus need not be renewed so often for the same output.

A substantial disadvantage of previously known neutral or acid developing compositions over alkaline developing materials is their low development speed. Despite the fact that acid developer substances usually comprise a coupler compound of substantial coupling activity, previously known diazo compounds having sufficient lightsensitivity exhibit a comparatively slight coupling activity with these developers in an acid solution. The prolongation of the period of development involved thereby results in the so-called bleeding of the copies. This phenomenon is apparent by a less sharp boundary of the image portions and in an enlargement of the lines thereof. This may be caused by the fact that the diazo compound dissolves in the aqueous developer solution during development and the azo dye formed by the dissolved diazo 3,547,637 Patented Dec. 15, 1970 compound deposits outside the lines of the image on the surface of the copy. Bleeding also may be caused by the fact that the azo dye formed in the image areas is washed away by the developer solution when being in contact therewith for a longer period.

Too low a development speed has the further disadvantage that the diazo compound which has been undestroyed in the image areas after exposure to light is not completely developed to form the azo dyestuff. This results in a high-contrast copy which, however, bleaches out when lying in the light, since the unreacted diazo compound which likewise is dyed is gradually destroyed. The quality of such copies thus can be judged only after some time.

Too slow a development of diazotype materials may result from too low a coupling speed of the diazo compound as well as from the known acid stabilizers contained in the material. The presence of acid stabilizers, however, is necessary for the most of the diazotype materials in order to achieve a sufiicient storability.

The coupling speed in neutral to weakly acid developer solutions also may be increased in either maintaining the developer solution at higher temperatures or heating the copy wetted with the solution of applying a thicker coating of developer liquid to the surface of the copy or increasing the concentration of the developer substance in the solution. But this either increases again the danger of bleeding or too much valuable developer substance is consumed.

SUMMARY OF THE INVENTION A group of new diazo compounds has now been found which, with the formation of red-brown to violet-brown dyestuffs, couple with weakly acid developer solutions containing phloroglucinol so rapidly that the above-described disadvantages are avoided.

The present invention provides a one-component diazotype material comprising, as the light-sensitive substance, a diazo compound of the general formula 1 NzX wherein:

R stands for an alkyl, aminoalkyl or hydroxyalkyl group,

and R stands for an alkyl or aralkyl group, or R and R together with the nitrogen atom to which they are attached stand for a heterocyclic radical;

R stands for hydrogen, halogen, an alkyl, alkoxy, alkylmercapto or arylmercapto group;

X stands for the anion of the diazonium compound; and

R stands for hydrogen, an alkyl or an aralkyl group, and R stands for an acyl, carboxylic amide radical or a radical of the structure wherein R and Y together with the carbon atom to which they are attached form a heterocyclic radical in which a nitrogen atom stands in the place of Y, or

R stands for an acyl, carboxylic amide radical or a radical of the structure wherein R and R together with the nitrogen atom and the carbon atom to which they are attached form a 5- or 6-membered heterocyclic radical, and Y stands for an oxygen atoms.

When the mentioned symbols stands for alkyl groups or radicals which contain alkyl groups such groups generally have not more than 4 carbon atoms; in the case of aralkyl radical they usually have not more than 10 carbon atoms, since too long carbon chains decrease the solubility of the substances in the coating solution in an undesirable manner.

Since a high coupling speed is of particular importance in the present invention such compounds are preferred in which either R is an aralkyl group or R and R together with the nitrogen atom form a heterocyclic ring which, in known manner, may also be substituted by short-chain alkyl radicals, e.g. methyl or ethyl radicals, having totally at most 4 carbon atoms. Unless certain effects are to be achieved-as in the present casegenerally such substituents are preferred as are particularly accessible. R thus preferably is chlorine, a methyl, methoxy or ethoxy group, a low alkyl or arylmercapto group. X is one of the known anions forming stable salts with diazonium compounds. The diazonium salt may also be employed in the form of a double salt, eg with zinc chloride, cadmium chloride or tannic chloride, or in the form of a salt with a complex acid, e.g. as hexafiuorphosphate or tetrafiuoborate.

It is characteristic of the diazo compounds of the present invention that they carry at the amino nitrogen in 2-position a substituent which contains a polarizable double bond in the immediate vicinity of the nitrogen atom. Apparently, such a substitution increases the coupling speed of the diazo compounds to the desired extent and exceeds the known effect of the aralkyl amino groups or the heterocyclic radicals in l-position.

This substitution further appears to displace in a most striking manner the spectrum of various azo dyes formed by the coupling of these diazo compounds with selected azo coupler components. Such color displacement is particularly noteworthy with respect to a number of alkalinedeveloping coupler components described in greater detail below.

The diazo compounds used in accordance with the present invention exhibit high light-sensitivity to all lightsources usual in the diazotype field. The diazotype material sensitized therewith is well suited for the visual observation of the end of exposure because of the distinct colouration of the diazo compound itself.

The diazo compounds used in accordance with the present invention couple exceptionally rapidly with weakly acid developer solution containing phloroglucinol to form red-brown to violet-brown azo dyes which absorb ultraviolet rays very well. The compounds thus are excelleritly suitable for the preparation of intermediate origina 5.

The azo dye images do not bleed and do not show any signs of bleaching out since the unexposed diazo compounds are developed very quickly and completely with the mentioned developers. Furthermore, the copies do not have a coloured background attributable to incomplete exposure to light.

The developers with which the diazotype materials of the present invention preferably are developed according to the semi-wet process are weakly acid or neutral 4 buffered solutions containing known rapid-coupling developer substances, e.g. phloroglucinol or mixtures of phloroglucinol and resorcinol or of acetoacetic ester derivatives. Although the present materials exhibit greatest advantage in acid systems, it is also possible, as previously noted, to develop the one-component diazotype materials of the present invention with most alkaline developers to achieve similarly good copies.

The diazotype materials of the present invention have been found to have particularly unusual properties with respect to the color of the dye formed through alkaline development with azo coupler components including 2,3- dihydroxy naphthalene and amides of 2-hydroxy-3- naphthoic acid. Whereas these developers have been known for use in the formation of blue dye shades with previous diazo compounds derived from 4-(N-methyl-N-benzyl)- amino aniline; 2,5-dimethoxy-4-amino-4-methyl-diphenyl sulfide; 3-ethoxy-4-(N-methyl-N-benzyl)-amino-aniline; 2- chloro-4-(N-methyl-N-benzyl)-amino-S-methoxy-aniline; 2-chloro-4-dimethylamino-S-(4-chlorophenoxy) aniline; and 2,5-di-(n-butoxy)-4-(N-morpholino) aniline; dyestuffs of outstanding red hues are formed by the coupling of such azo compounds with the diazo compounds of the present invention.

Developers for such red-line developing with the present diazotype materials are solutions buffered to a pH of about 8-11 and containing the noted naphthalene derivatives as coupling components.

Among the useful 2-hydroxy-3-naphthoic acid amides are those prepared with ethanolamine, diethanolamine, (2-hydroxyethyl)-(2-arninoethyl)-ether, 1,1-di-(hydroxyn1ethyl)-ethanolamine, aminoacetic acid, phenylarninoacetic acid, Z-(N-morpholino)-ethylamine, or N-methyl- N- Z-amino-ethyl -morpholine-methyl-sulfate.

Heretofore, multiple developer solutions, and consequently multiple developing devices, were required for the preparation of diazotype copies of varying colors. While some slight latitude in shade was previously available through a variation in diazo component, only a change in azo coupler component could result in a practical shift over a substantial range of dyestuif color spectrum. The materials of the present invention, however, will be seen to afford an unprecedented scope of dye color formation, i.e. from blue to red, with a single developer solution.

Further, the diazo compounds of the present invention, particularly those with shorter alkyl radicals, e.g. methyl and ethyl, comprising the R and R constituents of the above general formula, have been found to be not excessively fast coupling to prevent their use in two-component diazo-type material with common blue-coupling components to prepare a broader range of ammoniadeveloping red line materials.

A support of the diazotype material of the present invention may be opaque, such as paper, cloth, glazed paper; translucent, such as ooated or uncoated tracing-papers; or completely transparent, such as cellulose acetate or polyester film. When the surface of the support is hydrophobic, as in the case of cellulose acetate or polyvinyl ester films, e.g. polyvinyl acetate films, the diazo compound preferably is introduced into a thin hydrophilic film coating covering the hydrophobic surface of the support and obtained by hydrolysis of the ester groups of the cellulose esters or polyvinyl esters. When the support is transparent or at least translucent, the copies are excellently suitable as transparencies or as intermediate originals. As will be noted in greater detail in the examples, the support may contain materials such as dyes, light absorbers, and the like.

The one-component diazotype material of the present invention may contain the additives usual in such a case, e.g. citric acid, boric acid, tartaric acid, naphthalene-1,3,6- trisulphonic acid and the salts thereof soluble in water, reducing agents, such as thiourea, metal salts, such as aluminum sulphate, synthetic resin or silicate dispersions,

etc. Material containing such additives has a good storability.

The diazo compounds used in accordance with the present invention can be obtained according to the following general Methods I, II, III, and IV.

METHOD I Diazo compounds of the general formula wherein R and R stand for hydrogen atoms are obtained as follows: 1-chloro 2,4-dinitrobenzene is reacted in known manner with secondary amines, e.g. with dialkyl amines, alkylaralkyl amines or with heterocyclic bases containing secondary nitrogen and the chlorine atom in l-position is replaced thereby by a tertiary amino group. The nitro group in 2-position is then reduced with sodium polysulphide to form the amino group. The primary amino group thus obtained may be mono-substituted according to known methods with carboxylic chlorides, carboxylic anhydrides, alkyl or aryl sulphochlorides, reactive heterocyclic compounds, e.g. cyanuric chloride, with isocyanates or isothiocyanates. By reacting the amino group with butyrolactone in the presence of zinc chloride, the pyrrolidone ring indicated e.g. in Formula 27 is obtained. The conversion of the nitro group in 4-position into the diazo group is performed by reduction to form the amino group and diazotizing.

METHOD II For the preparation of diazo compounds of the general formula wherein R stands for an acyl group, a carboxylic amide group or a heterocyclic radical, R for an aralkyl group and R for hydrogen the following method is advantageously performed:

1-chloro-2,4-dinitro-benzene is reacted with the above mentioned secondary amines, the nitro group in Z-position is reduced to form the primary amino group which is monosubstituted with monohalogenated alkyl or aralkyl compounds and only then, as indicated above, acylated. The compounds obtained are reduced in 4-position to form the corresponding amino compounds which are then diazotized.

METHOD III Diazo compounds of the general Formula wherein R stands for a halogen, an alkoxy or alkyl group may be obtained, inter alia, in the following manner:

l-chloro-Z-nitrobenzene substituted in the 5-position by halogen, an alkoxy or an alkyl group is reacted, as indicated in Method I, in the 1-position to form the tertiary amine, the nitro group is reduced to form the amino group which subsequently is alkylated and acylated in the manner stated in Method II. The introduction of the diazo group into the 4position is performed in known manner, e.g. by coupling in the 4-position with a diazo compound to form an azo dye and subsequent reductive cleavage of the azo dye to form the amino, or by introduction of a nitro group which is then reduced to form the amino group and subsequently diazotized.

METHOD IV Diazo compounds of the general formula wherein R stands for an alkylmercapto or arylmercapto group may be synthesized as follows: In analogy to Method II, from 1,S-dichloro-Z-nitro-benzene there is obtained a 1-tert.- amino-Z-(N-alkyl-N-acyl-amino)-5-chloro-benzene, for example. Subsequent nitration is performed in 4-position and then the reactive chlorine atom in 5-position is exchanged for alkylmercapto or arylmercapto radicals. Reduction of the nitro group to form the amino group and diazotization thereof yields the corresponding diazo compound.

The following table presents a number of constitutent formulae of useful diazonium compounds of the present invention. The radicals shown are those of the general formula. The melting points listed are of the corresponding-4-nitro compounds.

TABLE Melting Method point, C. X

Example Formula No.

99-102 HPFa -COCHa 143-145 ZnClz 167-168 ZnClz 123-124 ZnClz H BEE H E 50001 H Z 55 2 E E0 Eoool h 5 Z 5E 2Z2 .& EO Q o Eoool N 1- Z QMTHHH QwH wwH 2H m om O MHHOOOI HM m :INH Z him om wfi H: m 0 A Wi 00 HH vi Z PHMEH NHN N H: -O JHOOOII m J IIIOH O Z :75 5 9: E 500 o 5000! m \j flO N @3 9: H m h J A wL mI. i wd 0 :05 832 H m A v wo 5o m -U FE mi; 5 6 ET ED o u m w 3 un OQJE 522 m Sm 3H "M 5H 2 02 nis QEQ 0 Z 65 3T8 H m o /\z N E .55 H mm ED SMO E0 0 0 0 m m \Z NHOQN @2123 H m @[0 OI. m m O Z PE 11% m m E0 0 1 E HO z ll NHOQN mmmlmmm Q m MHHO 0 0|. @lumnol. m mm HO 2 $32 E m E0 0 o @50 Z 65 H m @l 1 m 2 REM i H m 0 0 ol m E aonN ENISN H m m 50 E QL m m Q mm mmTmmH H m mO mO 0 0 0 O N wfifi H m MO MO oo m w 6 O 5 @181 m N 0 0 $3 @532 E 5 m Q E 52 355p 1 1' PREFERRED EMBODIMENTS The following examples illustrate the preparation of diazotype material of the present invention without limitation of the scope of the invention.

For illustration purposes, the preparation of one of the diazo compounds used in accordance with the present invention is given in connection with Example 1. The other compounds are obtained in a corresponding manner according to one of the Methods I to IV.

EXAMPLE 1 White photoprinting base paper provided with a precoat of finely divided silica and polyvinyl acetate is coated with a solution containing in 100 ml. of water 0.4 g. of tartaric acid 0.6 g. of aluminum sulphate 0.2 g. of gelatine and 1.8 g. of zinc chloride double salt of the diazo compound from l-(N-methyl-N-benzyl)amino 2 (N phenylureido)-4-amino-benzene (Formula 3) and dried. The light-sensitive material thus obtained is exposed to light under an original and developed in applying to its image side about g./m. of a solution which contains in 100 ml. of water 8.0 g. of trisodium citrate (anhydrous) 2.0 g. of sodium benzoate 0.1 g. of citric acid 1.5 g. of thiourea 0.5 g. of phloroglucinol 0.2 g. of sodium salt of isopropylnaphthalene sulphonic acid. The solution has a pH value of about 6.4. Copies with brown-red lines on a pure white background are obtained.

Similarly good results are obtained by employing, instead of the above-stated diazo compound, the zinc chloride double salt of the diazo compound from l-(N-methyl- N-benzyl)amino 2 (2-chlorobenzoyl)amino-4-aminobenzene (Formula 7) or from l-(N-methyl-N-benzyl) amino-2-(p-tolylsulphonyl)amino-4-amino-benzene (Formula 2), the fluoborate of the diazo compound from 1- (N-morpholino)-2-benzoylamino-4-amino-benzene (Formula 11) or the zinc chloride double salt of the diazo compound from l-(N-methyl-N-benzyl)amino-2-benzoyla-mino-4-amino-benzene (Formula 16).

The diazo compound of Formula 3 was obtained as follows:

250 parts by weight of 1-chloro-2,4-dinitro-benzene were suspended in 500 parts by volume of ethanol and reacted dropwise with stirring at to C. with 300 1 parts by weight of N-methyl-N-benzylamine. The mixture was subsequently heated with reflux for half an hour and cooled and the crystal mass obtained was thoroughly drawn off by suction. 31-0 parts by weight of yellowcoloured crude product percent of the theory) were obtained which, after recrystallization from ethanol, had a melting point of 139 to 140 C.

310 parts by weight of the obtained l-(N-methyl-N- benzyl)amino-2,4-dinitrobenzene were suspended in 1550 parts by volume of ethanol and a sodium polysulphide solution consisting of 322 parts by weight of Na S-9H O, 49.6 parts by weight of sulphur, and 405 parts by volume of water was slowly dropwise added with stirring at 60 to 70 C. in the course of 1 /2 hours. The mixture was then refluxed for another hour and, after cooling and leaving overnight, the crystallized product was drawn off by suction. 195 parts by weight (70 percent of the theory) of orange-red coloured flakes were obtained which, after recrystallization from ethanol, completely fused at 124 to C.

12.85 parts by weight of the thus obtained l-(N-methyl- N-benzyl) amino-2-amino-4-nitro-benzene were refluxed for 12 hours with 1 1.9 parts by weight of phenylisocyanate in 200 parts by volume of dioxane, the solvent was then distilled away in vacuo and the residue was recrystallized 12 from methanol. The yield was 10.8 parts by weight (60 percent of the theory) of pale yellow crystals having a melting point of 167 to 168 C.

35.8 parts by weight of the obtained l-(N-methyl-N- benzyl)amino-2-(N-phenyl-ureido)-4-nitro-benzene were catalytically reduced in 250 parts by volume of dioxane at 50 C. and normal pressure (Raney nickel as the catalyst). After filtering off the catalyst, the reduction product was precipitated in the form of colourless crystals by the addition of water. The yield was 31.3 parts by weight (95 percent of the theory); the melting point was 138 to C.

10 parts by weight of the thus obtained l-(N-methyl-N- benzyl)amino-2-(N-phenyl-ureido) -4-amino-benzene were diazotized in 300 parts by volume of hydrochloric acid (1:2) with the addition of 2 parts by weight of zinc chloride at 0 to 5 C. with a solution of 2.5 parts by weight of sodium nitrite and 20 parts by volume of water. The precipitate in the form of crystals was recrystallized from methanol (1:5). The yield was 5.8 parts by weight.

EXAMPLE 2 A transparent paper of the kind commonly used in diazotype processes is coated with a solution of 0.2 g. of gelatine 0.5 g. of tartaric acid 0.4 g. of aluminum sulphate and 2.5 g. of the stannic chloride double salt of the diazo compound from l-(N-methyl-N-benzyl)-a|mino-2-[4,6- dipyrrolidino-1,3,5triazinyl-(2)] amino-4-aminobenzene (Formula 4) in 10 ml. of isopropanol and 90 ml. of water and dried. After exposure to light under an original, the transparent copy is developed with the developer solution stated in Example 1. Copies with violet tinged brown lines are obtained. The dyes formed in the image areas are not permeable to ultraviolet light for which reason the copies are very suitable as intermediate originals for the preparation of further copies.

Similar results are obtained by using, instead of the compound of Formula 4, the hexafluophosphate of the diazo compound from l-(N-morpholino)-2-acetyl-amino- 4-amino-S-ethylmercapto-benzene (Formula 12), the fluoborate of the diazo compound from 1-(N-morpholino)-2- acety1amino-4-amino-5-(p-tolyl mercapto) benzene (Formula 13), the fluoborate of the diazo compound from 1- dimethylamino 2 (N-benzyl-N-acetyl)amino-4-aminobenzene (Formula 18), the zinc chloride double salt of the diazo compound from l-(N-pyrrolidino)-2-(N-o,odichlorobenzyl-N-acetyl)amino-4-amino-benzene (For-mula 23), the zinc chloride double salt of the diazo compound from l-(N-morpholino)-2-benzoylamino-4-aminobenzene (Formula 25), the stannic chloride double salt of the diazo compound from l-(N-methyl-N-benzyl)amino-2-ethyloxycarbonylamino-4-arnino-benzene (Formula 26) or the stannic chloride double salt of the diazo compound from l-(N-morpholino) 2 [N-(2-oxo-pyrrolidino) ]-4-amino-benzene (Formula 27).

EXAMPLE 3 Transparentized paper is coated with a solution containing in 100 ml. of water.

0.5 g. of tartaric acid 4.0 g. of naphthalene-1,3,6-trisulphonic acid (sodium salt) 0.4 g. of gum arabic 2.0 g. of the diazo compound from l-(N-methyl-N-benzyl)-amino-2-benzoyl-amino-4-amino-benzene (Formula 5).

By exposure to light under an original and development with the developer stated in Example 1, transparent copies with brown-red lines are obtained which are very suitable as intermediate originals.

1 3 EXAMPLE 4 Natural transparent paper is coated with the following solution:

0.5 g. of citric acid 3.5 g. of naphthalene-1,3,6-trisulphonic acid (sodium salt) 0.2 g. of gelatine 3.0 g. of the fiuoborate of the diazo compound from 1 morpholino-Z-acetylamino 4 amino-S-chloro-benzene (Formula 10) in 100 ml. of Water.

The paper is dried and exposed under an original and developed by applying about 10 g./m. of the following snhrtion:

5.7 g. of potassium adipate 2.3 g. of sodium benzoate 0.1 g. of adipic acid 0.5 g. of thiourea 0.6 g. of phloroglucinol 0.4 g. of resorcinol 0.2 g. of the sodium salt of isopropylnaphthalene sulphonrc acid in 100 ml. water.

The solution has a pH value of about 6.8. Copies with violet-brown lines, which are very suitable as intermediate originals, are obtained.

EXAMPLE 5 Transparent paper is lacquered with acetyl cellulose and the lacquer layer is saponified on the surface so that a thin coating of hydrophilic saponified acetyl cellulose is obtained. To this coating there is applied the following solution:

0.4 g. of tartaric acid 3.0 g. of naphthalene-1,3,6-trisulphonic acid (sodium salt) 0.4 g. of gum arabic 5.0 ml. of isopropanol 2.0 g. of the double salt from sodium chloride and the diazo compound from l-morpholino-2-(4-tolylsulphonyl) amino-4-amino-benzene (Formula 8) in 100 ml. of water.

The light-sensitive material is dried and exposed to light under an original and developed with the developer solution stated in Example 4. Transparent copies with redbrown lines the dyes of which are impermeable to ultraviolet light are obtained. The copies are thus very suitable r as intermediate originals.

EXAMPLE 6 White photoprinting base paper is coated with a solution of:

0.5 g. of tartaric acid 0.5 g. of aluminum sulfate 0.3 g. of gelatine and 1.9 g. of the diazo compound derived from 2-benzoylamino-l-(N-methyl N benzyl)-amino-4-aniline (Formula 5) in 100 ml. of water and dried. After exposure under a transparent drawing, the paper is developed with a solution containing 7.2 g. of potassium tetraborate 0.8 g. of potassium hydroxide 3.5 g. of thiourea 0.15 g. of the sodium salt of isopropylnaphthalene sulfonic acid, and

1.2 g. of 2-hydroxy-3-naphthoic acid ethanolamide in 100 ml. of water. The diazotype copies obtained show red lines on a white background.

Results of a similar quality were obtained by using one of the compounds corresponding to Formulae 1 to 4, 6, 11, 12, 17 or 26 in the coating solution described above.

Copies with blue lines on a white background are produced with the same developer solution when using a diazotype paper which contains e.g., the known diazo compound derived from 1 (N-ethyl N benzyl)-amino-aniline-4, as the light sensitive substance.

EXAMPLE 7 White photoprinting base paper provided with a precoat of polyvinyl acetate and colloidal silica is coated with a solution of 0.5 g. of citric acid 3.5 g. of the sodium salt of naphthalene-1,3,6-trisulfonic acid 0.2 g. of gum arabic, and

1.8 g. of the tetrafluoborate of the diazo compound desirved from 5-chloro-1-(N-morpholino)-2-acetylaminoaniline-4 (Formula 10) in ml. of water and dried. The diazotype paper thus obtained is exposed under a master and developed with the following solution:

in 100 ml. of water.

Copies with red lines on a white background are obtained.

Instead of the diazo compound mentioned above, the diazo compound derived from 5-methyl-1-(N-piperidino)- 2-acetylamino-aniline-4 (Formula 14) or the diazo compound derived from l-(N-morpholino) 2 [(2'-oxo)- pyrrolidino]-aniline-4 (Formula 27) were used with almost identical results.

EXAMPLE 8 White photoprinting base paper provided with a precoat of oat starch and polyvinyl acetate is coated with a solution of 0.5 g. of tartaric acid 2.0 g. of the sodium salt of naphthalene-1,3,6-trisulfonic acid 0.02 g. of saponine, and

1.6 g. of the diazo compound derived from Z-(p-tolylsulfonyl)-amino-l-(N-morpholino)-aniline-4 (Formula 8) in 100 ml. of water After drying and exposure under a transparent drawing, the copy is developed by means of the following developer:

7.0 g. of potassium tetraborate 2.5 g. of thiourea 0.1 g. of the sodium salt of isopropyl naphthalene sulfonic acid, and

0.8 g. of 2-hydroxy-3-naphtboic acid-ethanolamide in 100 ml. of water.

Diazotype copies with red lines on a white background are obtained.

Similar results were obtained when the diazo compound of Formula 8 Was replaced by the fluoborate of the diazo compound derived from 5-(p-tolylmercapto)-1-(N-morpholino)-2-acetylamino-aniline-4 (Formula 13).

EXAMPLE 9 Acetylcellulose film made of so-called 2 /2 acetate (i.e. containing 2.5 acetyl groups per glucose unit) which had been superficially saponified to a depth of about 1, was coated with a solution of 0.5 g. of tartaric acid 0.1 g. of saponine, and

3.5 g. of the diazo compound derived from 5-chloro-1-(N- methyl N benzyl)amino 2 benzoylamino-alinile-4 (Formula 16.

in 90 ml. of water and ml. of isopropanol, and dried.

By exposure under a master and development with the developer stated in Example 6, an image of the master in red lines is produced on the highly transparent film.

EXAMPLE 10 To a solution suitable for the preparation of an acetyl cellulose film (2.5 acetyl groups per glucose unit)), 2,5- di(p-dimethyl-aminophenyl)-1,3,4-oxadiazole, i.e. an ultraviolet absorber, was added in such a quantity that the finished film contained from 0.1 to 1.0 percent by weight of this compound, and a film was cast in known manner from this solution. On both surfaces of this film, a thin layer was deacetylated in known manner and thus hydrophilized.

Subsequently, the face of the film was coated with a solution containing 0.5 g. of citric acid 0.1 g. of saponine, and

3.5 g. of the zinc chloride double salt of the diazo compound derived from 2-(o-chlorobenzoylamino)-1-(N- methyl-N-benzyl-amino-aniline-4 (Formula 7) in 2.0 ml. of triethyleneglycol 10.0 ml. of isopropanol, and

88.0 ml. of water.

After the film had been dried, it was coated on the back with a solution of 0.5 g. of citric acid 3.5 g. of sodium salt of naphthalene-1,3,6-trisulfonic acid 0.1 g. of saponine, and

3.0 g. of the diado compound derived from l-(I-ethyl-N- benzyl)-amino-aniline-4 in 2.0 ml. of triethyleneglycol,

10.0 ml. of isopropanol, and

88.0 ml. of water; and dried.

The face of the film was then exposed under a master, using a carbon arc copying lamp as the light-source. Due to the ultraviolet absorber contained in the film, only a very small portion of the incident light penetrated to the back even in the non-image areas, so that the diazo compound on the back remained practically undecomposed. Subsequently, the back of the film was exposed through a carefully registered complementary master. Thus, two different yellow diazo images were produced on the two surfaces of the film. When looking through the film, the two images supplement each other to form a complete image.

When the reproduction material thus prepared is developed with the developer described in Example 7, using a customary semi-wet developing apparatus in which the developer solution is applied to both sides of the reproduction material, the image on the face of the film is developed in red lines and that on the back of the film in blue lines. When looking through the film, an image in two colors becomes visible.

The above examples have been presented for the purpose of illustration and should not be taken to limit the scope of the present invention. It will be apparent that the described examples are capable of many variations and modifications which are likewise to be included within the scope of the present invention as set forth in the appended claims.

What is claimed is:

1. One-component diazotype material comprising a support and a light-sensitive coating thereon, said coating including a diazonium compound of the general formula wherein:

R is an alkyl having seven to four carbons, and arylalkyl having one to ten carbons, or hydrogen;

R is an alkyl having one to four carbon atoms, and arylalkyl having seven to ten carbon atoms; or

R and R together with a nitrogen atom form a 5, 6 or 7-membered heterocyclic radical;

R is hydrogen, chlorine, alkyl having one to four carbon atoms, alkoxy having one to four carbon atoms, alkylmercapto having one to four carbon atoms, or arylmercapto having six to ten carbon atoms;

R is hydrogen, alkyl having one to four carbon atoms,

aryl-alkyl having seven to ten carbon atoms;

R is alkylacyl having one to five carbon atoms, arylacyl having seven to ten carbon atoms, phenylcarboxylic acid amide, phenylsulfonyl, alkyl carboxylic ester, or a 1,3, S-triazine radical or;

R and R together with the nitrogen atom form a fivemembered heterocyclic ring having a double bonded oxygen group substituted to the carbon atom in the two position of said heterocyclic ring; and

X is the anion of the diazonium compound.

2. Diazotype material comprising:

(a) a support absorbent of ultraviolet light and transmissive of longer wavelength visible light;

(b) a coating on one side of said support comprising a light-sensitive diazotype composition according to claim 1; and

(c) a coating on the opposite side of said support comprising a light-sensitive diazotype composition including a diazonium compound normally forming a blue azo dye through alkaline coupling with an azo component selected from the group consisting of 2,3- dihydroxy naphthalene and 2-hydroxy 3 naphthoic acid amides.

3. A method of preparing multi-color diazotypc reproductions which comprises:

(a) providing material according to claim 4;

(b) image-wise exposing one of the coated sides of said material to a first pattern of ultraviolet light for a time sufficient to image-wise decompose the diazonium compound of the composition coated on said one side;

(0) image-wise exposing the other of the coated sides of said material to a second pattern of ultraviolet light for a time sufficient to image-wise decompose the diazonium compound of the composition coated on said other side; and

(d) contacting both sides of the exposed material with an alkaline developer solution comprising an azo coupler component selected from the group consisting of 2,3-dihydroxy naphthalene and 2-hydroxy-3- naphthoic acid amides in order to form azo dye image in the unexposed areas of the said coatings of the diazotype material.

4. Material according to claim 1 wherein said diazonium compound is 3-(o-chlorobenzoylamino)-4-(N-methyl- N-benzyl)-amino benzene diazonium zinc chloride double salt.

5. Material according to claim 1 wherein said diazonium compound is 2 chloro 4 (N-methyl-N-benzyl)- amino-S-benzoylamino benzene diazonium zinc chloride double salt.

6. Material according to claim 1 wherein said diazonium compound is 3 (p tolyl sulfonyl)-amino-4-(N- 1 7 morpholino) benzene diazonium zinc chloride double salt.

7. Material according to claim 1 wherein said diazozonium compound is 2 chloro 4 (N-morpholino)-5- acetylamino benzene diazonium tetrafluoroborate.

8. Material according to claim 1 wherein said diazonium compound is 3 benzoylamino 4 (N-methyl-N- benzyl)-amino benzene diazonium zinc chloride double salt.

9. Material according to claim 1 wherein said diazonium compound is 4 (N methyl N-benzyl)-amino-3- [4,6 dipyrrolidino 1,3,5 triazinyl-( 2) ]-amino benzene diazonium stannic chloride double salt.

10. Material according to claim 1 wherein said diazonium compound is 4 (N methyl N-benzyl)-amino-3- (N'-pheny1-ureid0) benzene diazonium zinc chloride double salt.

References Cited UNITED STATES PATENTS 3,155,512 12/1964 DeBoer 9691 3,338,713 8/1967 Hendrickx et a1. 9691 3,397,985 8/1968 Hendrickx 9691 FOREIGN PATENTS 538,869 2/1941 Great Britain 96-91 3,910,164 6/1964 Japan M 9675 1 8 OTHER REFERENCES Camera, Colour with Diazo Film, vol. 43, N0. 12, December 1964, pp. 46 and 47.

Kosar, J.: Light-Sensitive Systems, August 1965, p. 212.

Landau, R.: Fascicules 1218, 1960, p.37 and p. 56.

Landau, R et al.: Diazo Compounds in the Photocopying Ind, the J. of Photo Sc., vol. 13, 1965, pp. 14415.

Index of German Reports on Diazotype Research of Kalle & Co., A.G.

Gen. Anil. Film Corp., Report No. RM-168. Apr. 6, 1956, p. 17.

PB 44231 (Fiat Report), p. 1106.

Weiner et al., Diazoty-pe Papers, The Inst. of Paper Chem, Biblio Series No. 220, 1965, Abstract No. 235.

NORMAN G. TORCHIN, Primary Examiner C. BOWERS, Assistant Examiner US. Cl. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,547,637 Dated ll] 15 December 1970 Inventofls) Siegfried Scheler, Wiesbaden-Schierstein, Iohannes Mund Weisbaden-Biebrich and Arno Brauninger. It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 16, Line 11, change "seven" to read one---;

Column 16, Line 12 change "one" to read --seven--;

Column 16, Line 48, change "Claim 4" to read --Claim 2----.

Signed and sealed this 23rd day of March 1971.

(SEAL) Attest:

EDWARD M':'FLETCHER,JR. WILLIAM E. SCHUYLER IR Attestlng Officer Commissioner of Patent.