DE879204C - Filter layer for color photography - Google Patents

Description

The invention relates to dyes for filter layers, how they are used in color photography.

In color photography processes in which different sensitive layers on a film or paper base are applied and the top layer is used to reproduce the blue it is necessary to place a yellow filter layer between this top layer and the remaining photosensitive Laying out layers so that any blue light that passes through the top layer does not hit the underlying layers which, other than being sensitive to it certain parts of the spectrum are also sensitive to blue. For this yellow filter layer is it has been customary to use a gelatin layer containing colloidal silver; however this has How it works many disadvantages. The preparation of the colloidal silver dispersion with the necessary Light absorption properties are costly and require a lot of time and experience, and the final dispersion can only be stored in a satisfactory manner in a cold room. In addition, the dispersed silver tends to fog the boundary between the silver layer and the sensitive layers, so that it may be necessary for certain purposes to use a special layer to be provided on each side of the filter layer. There is also that in terms of optical Properties colloidal silver is not ideal because

the total black content of the colloidal silver layer reduces the effective sensitivity of the lower sensitive layers.

It has been proposed to replace the colloidal silver filter layer with a yellow dye filter layer zu.ersetzen ,, however, no dyes are known to date been, which in terms of the absorption properties, the lack of diffusivity and the ease of being a perfect and 'not

ίο bring about reversible discoloration, perfectly are satisfactory, and the use of a yellow dye filter layer for this reason has not yet found any practical meaning.

The invention now proposes dyes which are used in filter layers in color photography and these dyes can be used in place of colloidal silver, and they do not have the disadvantages associated with the use of colloidal silver.

According to the invention, a new filter layer is now proposed that is used in color photography Can be used, and this is characterized in that the filter layer contains a dye the general formula

CN R ₉

= CH-

go ^R l ^{C0 R} 3

contains, wherein R _{1 is} an aryl or arylamino _{radical, R 2 is} hydrogen, alkyl or substituted alkyl and R _{3 is} alkyl or substituted alkyl, in which the phenylene nucleus can have substituents and in which the radical R _{1 has} a substituent which has an alkyl chain of at least 5 Contains carbon atoms.

The substituent of the alkyl group of R ₂ and R ₃ can consist, for example, of hydroxy, alkoxy, nitro, halogen or cyano radicals, sulfonic acid groups, carboxylic acid groups or esters thereof.

The radical R ₁ can, for example, be the p - (/ S-octa-

decenylsuccinamido) phenyl radical or the p-lauroylaminophenyl radical be.

The invention also relates to a multilayer photographic material which contains a dye of the above formula in at least one filter layer.
The new dyes can thereby be produced

• 50 that the corresponding cyanoacetyl color former is condensed with an anil of the appropriate N-substituted p-aminobenzaldehyde.

Examples of suitable N-substituted p-aminobenzaldehydes are: p-methyl-aminobenzal-

dehyd, p-ethylaminobenzaldehyde, p-methylethylaminobenzaldehyde, p-dimethylaminobenzaldehyde, p-diethylaminobenzaldehyde, p-dipropylaminobenzaldehyde, p- (N-methyl-N- _j S-hydroxyethylamino) -benzaldehyde, p- (N-ethyl-N- _J S. -hydroxyäthylamino) -benzaldehyde, p- (/ 9, j3'-dihydroxydiäthylamino) -benzaldehyde, ρ - (N - methyl - N - methoxyäthylamino) - benzaldehyde, p- (N-ethyl-N-methoxyäthylamino) -benzaldehyde, p- (N-Butyl-N - ^ - hydroxyäthylamino) -benzaldehyde, p- (N-

Methyl-N- / S-chloroäthylarnino) -benzaldehyde, p- (N-

Ethyl-N- _J ö-chloroethylamino) -benzaldehyde, p- [ß, / 5'-dichlorodiethylamino) -benzaldehyde, 4-Q3, jS'-dichlorodiethylamino) -2-methylbenzaldehyde, p- (N-methyl-N- / ? - cyanoethylamino) benzaldehyde, p - (/ J, /? '- dicyanodiethylamino) benzaldehyde, p- (N-methyl-N - /? - carboxyethylamino) -benzaldehyde, p-di- (carboxymethyl) -amino-benzaldehyde and the corresponding diethyl ester, p - (/ J, /? '- dicarboxydiäthylamino) benzaldehyde, p- (N-methyl-N-ß-sulfoäthylamino) -benzaldehyde, 4 ~ (ß, ß'- disulfodiäthylamino) -2-methyl -benzaldehyde.

The N-cyanoalkyl or N-dicyandialkyl substituted p-Aminobenzaldehydes can be prepared in that the corresponding hydroxyalkyl or dihydroxyalkylanilines treated with phosphorus pentabromide, whereupon the corresponding bromoalkyl or dibromodialkyl compounds obtained in this way treated with potassium cyanide and then the aldehyde group by reaction with phosphorus oxychloride and N-methylformanilide and subsequent hydrolysis is introduced, d. H. it is based on the method of Vilsmeier and Haack (reports, vol. 60, p. 119) worked. The diethyl ester of p-di- (carboxymethyl) -amino-benzaldehyde can be prepared by removing the aldehyde group in p-di- (carboxymethyl) -anüin the process described by Vilsmeier and Haack is introduced, and the free acid can can be represented by hydrolysis of the ester. The remaining mono- or di- (carboxyalkyl) derivatives can by hydrolysis of the corresponding cyanoalkyl compounds, and the esters can can be generated by reacting the acids with the corresponding alcohol. The mono- and di- (sulfoalkyl) derivatives can by the action of sodium sulfite on the corresponding chloroalkyl compounds getting produced.

The aldehyde can be converted into the corresponding anil by condensing it with aniline or a substituted one Aniline can be converted, for example with Anüinsulfonsäure, and the reaction of the anil with the cyanoacetyl compound can be obtained by heating the reactants in methanol with a catalyst, such as piperidine or triethylamine, or by mixing the reactants in a dilute alkaline Solution.

The dyes can be incorporated into a gelatin solution in the form of their soluble salts, and these Solution can be applied in the usual way as a filter layer in a multicolor film. As a result the presence of the long alkyl chain in the molecule does not diffuse these dyes into the neighboring ones photosensitive layers.

These dyes are particularly useful as a filter layer of multilayer films and paper, which Have three different photosensitive layers and the at least three non-diffusing layers Contain color former, the top layer being sensitive to blue and containing a yellow color former and the next layer represents the filter layer and one of the two further layers below is sensitive to red light and the other is sensitive to green light and one of these two lower ones

Layers contains a magenta color former and the other contains a cyan color former.

If such a multi-layer color film or a corresponding paper in the filter layer a containing the dyes according to the invention and exposing them to the light of a colored object or the light that passes through a colored transparency and the exposed film or the paper is then subjected to color development with a color-forming developer to obtain the Convert color formers into azamethine or indophenol dyes and then this film or paper is bleached, the filter layer can be completely and irreversibly decolored without a there is a significant influence on the azamethine and indophenol dyes that represent the color images, by treating the film or paper with a dilute solution of hydrazine hydrate and preferably in the presence of a surfactant, followed by the reaction products be washed out.

The dyes according to the invention can also be used in other types of filter layers such as the formation of halos preventing layers and the like.

Obviously, by appropriately changing the kinds of R ₁ , R ₂ and R _3, it is possible to select the dyes with absorption properties which are particularly suitable for particular purposes.

The absorption maxima of the dyes are generally between 430 and 480 ταμ.

The filter dyes according to the invention are free from the undesirable properties of colloidal Silver. They have a good color value; they become more perfect and permanent through the action decolorized by hydrazine hydrate solution, and they are generally the nondiffusible ones used hitherto Superior to yellow filter dyes in terms of light absorption properties.

In the following examples, some embodiments of the invention are given, followed by this but are not limited. The parts are parts by weight.

example 1

5 parts of piperidine are added to a hot suspension of 11.4 parts of p - (/ 3, /? '- Dicarboxyäthylamino) -benzaldehydanil and 17 parts of i - /? - octadecenylsuccinamido-4-ft> -cyanacetobenzene added in 250 parts of methanol. The clear solution thus obtained becomes 1 hour long boiled on the reflux condenser. The solution is then cooled and poured into 1000 parts of water, and the mixture thus obtained is acidified to Congo red paper by adding hydrochloric acid.

The precipitated dye is then filtered off, washed well with water and placed in a vacuum desiccator dried.

25 parts of this dye are in the form of the sodium salt in 1000 parts of a gelatin solution dissolved, and this solution is applied as a filter layer on a multilayer photographic material. This dye layer has an absorption maximum at 448 m // ,.

Example 2

5 parts of piperidine are added to a hot suspension of 10 parts of p- (N- / 3-sulfoethyl-N-methyl-amino) -benzaldehydanil and 15 parts of i-ß-octadecenyl-succinamido-4- (M-cyanoacetobenzene added in 300 parts of methanol. The clear solution thus obtained is refluxed for 2 hours. the Solution is evaporated to dryness by heating in vacuo and the residue is in Dissolved 200 parts of water. The dye is precipitated by adding concentrated »hydrochloric acid, filtered off, washed with water and dried in a vacuum desiccator.

If this dye is applied as a filter layer in a multilayer film in the manner indicated in the example, the filter layer has an absorption maximum at 445 m / t.

Example 3

Instead of the 17 parts of i-β- octadecenylsuccinamido-4-co-cyanacetobenzene used in Example 1, 11 parts of i-lauroylamino ^ -co-cyanacetobenzene can also be used.

Example 4

Instead of the 10 parts of p- (N- /? - sulfoethyl-N-methylamino) -benzaldehydaml used in Example 2, 8.7 parts of p- (N- / I-carboxyethyl-N-methylamino) -benzaldehydanil or 12, 6 parts of p- (N - />, ß'-Oi sulfoethyl-amino) -o-methyl-benzaldehydanil are used.

Claims (2)

PATENT CLAIMS: i. Filter layer for color photography, characterized in that, that the filter layer contains a dye of the general formula CN Ro C = CH- —N R ₁ CO contains, wherein R _{1 is} an aryl or arylamido radical, R _{2 is} hydrogen, alkyl or substituted alkyl and R _{3 is} alkyl or substituted alkyl, wherein the phenylene nucleus can have substituents and wherein the radical R ₁ bears a substituent which is an alkyl chain with at least 5 Contains carbon atoms. 2. Filter layer according to claim 1, characterized in that that the dye from i - /? - Octadecenyl-succinamido-4-ft> -cyan-ß) - (p-N, N-di- (carboxyethyl) -amino-benzylidene) -acetobenzene consists. 1 5033 6.