DE1547758B - Hardening of gelatine-containing photographic layers - Google Patents

Description

The invention relates to the hardening of gelatin-containing photographic layers with two N-substituted ones Compounds containing ethyleneimine radicals.

Protein-like colloids, for example gelatine, are known to have a low stability compared to the Exposure to water, water vapor and moisture. So are the gelatin layers, for example photographic recording materials when and not immersed in water have been hardened, soft very quickly with swelling. They even lose at higher temperatures their shape and possibly detach from the support.

However, since the action of water or water vapor on proteinaceous colloids does not always change can prevent, efforts were made to eliminate these disadvantages. As is well known, photographic, layers containing proteinaceous colloids, e.g. B. photographic silver halide emulsion layers, in the development of photographic recording materials with such layers of action exposed to aqueous developer solutions, eliminating them in the specified manner in the absence be adversely affected by stabilizers or hardeners.

The invention is based on the knowledge that gelatin-containing photographic layers in excellent Ways can be cured if they are with certain two N-substituted Äthyleniminreste containing compounds treated.

The German patent specification 1,165,405 and the German Auslegeschrift 1,081,169 already show similar ones Compounds known which are also suitable for hardening photographic layers, in particular of Gelatin, are suitable. However, these known hardeners are limited in their effectiveness, so that efforts were made to find better hardeners for gelatin-containing photographic layers.

The invention relates to the hardening of gelatin-containing photographic layers with two Compounds containing N-substituted ethyleneimine radicals, which is characterized in that the Compounds correspond to the general formula

5%, based on the weight of the gelatin, applied.

The gelatin-containing photographic layers hardened according to the invention can be applied to the most varied of layers conventional support, for example those made of paper or high polymers, such as them commonly used for the production of photographic recording materials are applied being.

ίο If the gelatin to be hardened is already in the form of a finished layer, it can be mixed with an aqueous solution of one of the compounds used according to the invention are treated, after which, for example, at room temperature or at higher Temperatures can be dried.

According to a preferred embodiment of the invention, gelatin-containing photographic material is used for hardening Layers of bis [2- (ethyleneimine) ethyl] sulfone are used. This configuration gives you a hardened gelatin-containing layer which shows extremely little swelling in water.

This can bis [2- (l-ethyleneimine) ethyl] sulfone, for example, be prepared as follows: To 20 parts by weight of ethyleneimine a temperature below 1O ⁰ C are added dropwise 18.3 parts by weight of divinyl sulfone was added with stirring. The temperature is kept at about 15 to 20 ^° C. for 2 hours, after which the excess amine is drawn off with a water jet pump. The residue is distilled in vacuo. This gives about 27.4 parts by weight of a straw-colored oil. This Ul is solid at a temperature of about 36.5 to 39.5 C ^0. It can be recrystallized from ether and forms large, colorless needles with a melting point of 37.5 to 39 ° C. (cf. Bestian, "Ann.", 566, 238 [1950]).
If you z. B. from the connection

40

45

N-CH ₂ -CH ₂ -A-CH ₂ -CH ₂ -N
where A groups of the formula are:

where m = 0 to 3 and η = 1 to 8.

The compounds used according to the invention can easily be applied from aqueous solutions bring. For example, they can be mixed with the gelatin solution in the form of an aqueous solution whereupon the colloid or emulsion, e.g. B. a silver halide emulsion, in a conventional, known manner Way, can be applied to a substrate. Then the applied Layer can be dried with the help of a stream of warm air, for example.

The amounts of compounds according to the invention used to harden the gelatin are not critical, but amounts from 0.5 to CH ₂ = CHCO (CH ₂ ) ₄ COCH = CH _{2 are preferred}

starts, the compound of the formula is obtained in the manner described above

PnCH ₂ CH ₂ CO (CH ₂ ) ₄ COCH ₂ CH ₂ n1 (compound A)

However, no protection is sought for the production of these compounds.

The following examples are intended to explain the invention in more detail.

example 1

A common gelatin-silver halide emulsion was added at 1.13 weight percent based on dry weight added to the gelatin, bis [2- (l-ethyleneimine) ethyl] sulfone. The emulsion was then applied to a applied with an intermediate layer cellulose triacetate support. For comparison purposes became a corresponding photographic material using an emulsion produced which did not contain bis [2- (l-ethyleneimine) ethyl] sulfone.

The melting points of the emulsion layers were determined after the recording materials had a Had been stored at a temperature of 49 ° C for one week. For this purpose, the Recording materials immersed in water, whereupon the temperature of the water increases by 1 ° C per second

was increased. The temperatures at which the emulsion layers dissolved were determined. the The results obtained are summarized in the following table:

Weight percent, Melting point based on the the emulsion Hardening agents dry gelatin after several weeks storage _ at 49 ⁰ C _ 29 ° C (Comparison material) Bis [2- (l-ethyleneimine) - 1.13 ethyl] sulfone 100 ° C

Example 2

Various proportions of the gelatin-silver halide emulsion described in Example 1 were used Compound A added in various concentrations. The emulsions hardened in this way were then applied to substrates. Subsequently, the swelling capacity or the swelling of the gelatin layers in water. The percentage increase in thickness of the wet or wet emulsion layers are determined against the corresponding dry layers.

The following table shows the hardener concentrations used and the percentage Swelling of the emulsion layers indicated after immersion in water:

Hardening agents concentration
of hardening
by means of
mg / 139 g gelatin % Swelling
in water comparison material)
Connection A
Connection A 2.1
10.5 910
390
220

it is compound III of German patent specification 1,165,405, compound 3 is a minor one modified derivative of the compound I of the patent mentioned. In all investigated known Compounds are known hardeners, which are under claim 1 of the German Interpretation document 1081 169 fall.

a) Compounds used according to the invention

NCH ₂ CH ₂ SO ₂ CH ₂ CH ₂ N

NCH ₂ CH ₂ CO (CH ₂ kCOCH ₂ CH ₂ N
(identical to connection A)

b) Known connections

N I = C = N ^ f V-N = C =. IN

OCN

NCO

O, N

OCN

From the results given above, it can be seen that the one used in the present invention Compound A was able to harden the gelatin layers in an excellent manner.

Example 3

Various proportions of the gelatin-silver halide emulsion described in Example 1 were made Compounds 1 to 6 given below in those given in the table below Concentrations added. The emulsions hardened in this way were applied to substrates, and then their swelling ability or swelling upon immersion in water was determined. The observed percentage increase in thickness compared to the wet or moist emulsion layers the corresponding dry layers is also given in the following table. To the Control, a recording material was treated at the same time in an identical manner, but none Hardener compound contained.

The compounds examined are compounds (compounds 1 and 2) or known hardener compounds (compounds 3 to 6). When connecting 4

The table below shows those tests carried out in accordance with Example 2 Hardener concentrations and the percentage swelling of the emulsion layers after immersion compiled in water.

55
Hardening agents
60 concentration
of hardening
by means of
(Weight percent,
based on the
dry gelatin) Percentage
Swelling
in water (Comparison material!)
ί
(Comparison material) 3
6th 783
178
85
760

continuation

concentration Percentage of hardening Swelling
in water . Hardening agents by means of
(Weight percent,
based on the dry gelatin) 290 *) 2 0.37 119 2 4th 860 (Comparison material) 640 3 3 620 3 6th 760 --- , · ■ (Comparison material) 260 4th 3, 210 4th 6th 660 (Comparison material) 650 5 3 540 5 6th 750 _ (Comparison material) 420 6th . 3 460 6th 6th

*) The closely related connection

NCOCH ₂ CH ₂ CON

The data presented above show that the hardener compounds used according to the invention a better hardening effect (see compound 1) than the known hardener compounds (compounds 3 to 6) or with a lower concentration an equally good hardening effect (see connection 2) exhibit. This is particularly clear when the results obtained using compounds 1 and 2 are obtained Results obtained using the best known hardener compound (compound 4) Compares results.

Claims (2)

Patent claims: 1. Hardening of gelatin-containing photographic layers with two N-substituted ethyleneimine residues containing compounds, characterized in that the compounds correspond to the general formula N-CH ₂ -CH ₂ -A-CH ₂ -CH ₂ -N
where A groups of the formula are:
- (CH ₂ L-SO ₂ - (CH ₂ L- resulted in only a slight hardening (m.p. 94 ° C compared to 84 ° C des Comparison material) despite 57% concentration, the swelling values were not measurable. or - CO- (CH ₂ ) "- CO- where m = 0 to 3 and η = 1 to 8. 2. Hardening according to claim 1, characterized in that bis [2- (l-ethyleneimine) ethyl] sulfone is used.