DE1284290B - Process for curing photographic gelatin layers - Google Patents

Description

1 2

The invention relates to a method for hardening chlorine-6-hydroxy-s-triazine anion plays, which contributes to the photographic gelatin layers by means of a crosslinking of the gelatin molecules. M can be 2,4-dichloro-s-triazine compound. z. B. be: sodium, potassium, lithium, calcium, most photographic materials contain barium, strontium, ammonium tetramethyl, amhalten gelatin as an essential component. This ₅ moniumtetraäthyl, Ammoniumtetrapropyl or Ametrifft z. B. Halogen silver emulsion layers, protective monium tetrabutyl. The compounds of the all-story, substrate layers for film production, my formula 'are produced by partial antihalation layers, backing layers, etc. Such hydrolysis of trichloro-s-triazine in an aqueous gelatin layer often has to be carried out several times with an aqueous alkali solution under carefully controlled conditions. Solutions are dealt with that also have different _I0 The execution is analogous to that in the »Journal of the pH values and temperatures. Society of Organic Synthetic Chemistry ", Japan, layers of untreated or non-hardened Vol. 18, pp. 175 to 183 (1960), described VerGelatine have only low water resistance, and drive.

the gelatin layer swollen in water is extremely sensitive to the trichloro-s-triazine has a very reactive mechanical damage. Be, ₅ chlorine atom and can therefore under relatively special at higher temperatures, the gelatin is hydrolyzed under mild conditions and soluble to form salts in aqueous solutions. of 2,4-dichloro-6-hydroxy-s-triazine reacted who-There are various known as curing agents. The chlorine atoms of this dichloro compound are known, through which the water is much less reactive than the strength of photographic gelatin _{layers 2} o trichloro-s-triazine and can only be improved a lot. These include B. inorganic more severe reaction conditions who hydrolyzed compounds, such as chrome and aluminum alum, the. As a result of these differences, one can choose those and organic compounds, such as formaldehyde, reaction conditions that hydrolyze polyfunctional epoxides, ethyleneimines and, after the formation of 2,4-dichloro-6-hydroxy-s-triazine, fourth vinyl compounds. 25 comes to a standstill and practically no di- The known hardeners, however, lead to hydroxy and trihydroxy compounds, undesirable and disadvantageous phenomena. The conditions are particularly severe, the deterioration of Examples 2 and 3 can be seen from the following, the photographic properties, e.g. B. by One can therefore with advantage in increasing the haze and reducing the sensitivity of a 2,4-dichloro-6-sensitivity according to the invention. Furthermore, due to insufficient droxy-s-triazine salt due to partial hydrolysis of the water solubility of the hardening agent, difficult-trichloro-s-triazine accruing solution without previous opportunities, which leads to unevenness in the isolation of the dichlorotriazine salt, required gelatin layer. Some curing agents are appropriate to use after dilution as a curing agent in the solid state or dissolved chemically _35th It saves the separation, unstable or toxic. There are also hardeners, cleaning and redissolution of the triazine salt. that in the presence of other additives required, one advantage of the new hardeners, such as stabilizers or color couplers, is their hardening in the rapid hardening of the gelatin. This is losing its effect. In the production of photographic material, furthermore, 40 is of great importance from Austrian patent specification, since this means that even compounds with a 2,4-diminutive quality are known as gelatin hardeners while avoiding a post-chlorotriazine ring, but hardening is achieved can. The photographic property for their production due to their complicated shafts, these hardening agents do not require a considerable amount of effort. influenced. The hardening process is not disturbed by the presence of other photographic additives and not disturbed by various substances in aqueous solutions. As a result of these advantages, the new pH values and hardeners, even at elevated temperatures, can be made particularly insoluble in color photography, without being suitable for photographic material which, among other things, has unfavorable side effects. Color-forming couplers in the gelatin layer. An object of the invention is a method for working. The toxicity of this hardening hardening of photographic gelatin layers by means of medium is very low.

a 2,4-dichloro-s-triazm compound, which is characterized compared to the Austrian patent that a compound of the general = -schrift 230 736 known compounds with a my formula 2,4 dichlorotriazine ring distinguishes the compounds

N '55 according to the invention in that they have a lot

/ \ have a simpler structure and are much easier to

Cl C C Cl are to be delivered. In addition, you need much less

Il I amounts by weight of compounds according to the invention

N N fertilize to have the same hardening effect as with

\ q / 60 to achieve the known connections,

l The incorporation of hardeners into the

O M 'gelatin layer can be done in different ways, z. B. they can before coating the

is applied, in which M alkali, alkaline earth or gelatin solution are added, or it can

means a quaternary ammonium group. ⁶ S a dried gelatin layer in a solution

For the cationic group of the curing agent labeled M to be immersed, There are a great number of groups available, as aqueous gelatin is used for effective hardening only the role of the counterion to the 2,4-dimemix preferably at a pH of

5 to 12 held. Outside this range, a salt of 2,4-dichloro-6-hydroxy-s-triazine is used and hydrolyzed to di- or trihydroxy derivatives, which have a worse hardening effect than the Have monohydroxy compounds.

The amount of hardener to be added varies within wide limits, as it depends on the type depends on the gelatin dispersion or emulsion used. The preferred amount added generally ranges from 1 to 50 grams of hardener per kilogram of dry gelatin; for photographic Material 1 to 30 g is best. With these amounts, an effective and extensive hardening is achieved that the gelatin layers not damaged in the photographic treatments even at elevated temperatures will.

In certain cases, the new hardening agents can also be used in combination with other hardening agents agents can be used to achieve special hardening effects.

To further explain the invention, the multitude of possible applications some exemplary embodiments are given. For the production of the hardeners themselves, whether isolated or as a non-isolated reaction product, no protection is sought.

example 1

To an alkaline solution of 90 g of sodium bicarbonate in 430 ecm of water were during one hour at 35 ° C. 66 g of trichloro-s-triazine were gradually added. The solution was during Maintained at 35 ° C. for a further hour. It was then clear and was filtered. The filtrate was Cooled to about 5 ° C. overnight, 50 g of the sodium salt of 2,4-dichloro-6-hydroxy-s-triazine being obtained. This crude salt was obtained from an aqueous solution containing weakly alkaline sodium bicarbonate Solution recrystallized. The analysis showed for

C 25.00, N22.34 ⁽⁾ / ":
C 24.83, N 22.17%.

Calculated
found

20 ecm of a 2 percent strength by weight aqueous solution of this hardener became 1 kg of one added to the photographic silver bromide emulsion containing 80 g of gelatin and 15 g of the coupler of the following Formula contained:

17-35

-C = N

The emulsion was adjusted to pH 7 and poured onto a film base made of polyethylene terephthalate and dried.

The melting points of the emulsion layer were measured under various conditions and compared to an emulsion with no hardener. The results are shown in the following table:

Melting points in water, C.
Time after coating

4 days

15 days

28 days

2 days

45 "C, 80 ^u / o relative
humidity

Without hardeners

Cured according to example 1

32 70

32
over 90

32
over 90

After developing in a 4-amino-3-methyl effect of different amounts added shows the following Color developer containing Ν, Ν-diethylaniline shows 45 Table: the emulsion treated with the hardener has the same photographic properties, in particular in terms of color density, speed and fog as those not with hardener treated emulsion. 5 °

Example 2

A warm solution of 660 g of trichloro-s-triazine in 2.41 acetone was in a solution of 663 g of sodium bicarbonate in 41% of water was added dropwise at 35 ° C. A clear solution with a pH of about 8.5. This solution was cooled to 20 ° C., filtered and made up to 6.61 with water. The analysis indicated that the solution was approximately 10 percent by weight contained in the sodium salt of 2,4-dichloro-6-hydroxy-s-triazine.

The solution was then mixed with 1 kg of a photographic emulsion of bromiodide silver containing 70 g of gelatin mixed. A cellulose triacetate film backing was coated with this emulsion and dried at room temperature. The hardening

lOweight Melting point in water, "C 4 days 28 days percent hardening
medium solution pro Time after loading 32 32 · 1 kg of emulsion
ecm ,. fresh 75 over 90 0 32 over 90 over 90 2 45 over 90 over 90 4th 70 6th 85

Fifty-five tests revealed that the cured film was free from fog and compared to one uncured showed no deterioration, in particular with regard to sensitivity and contrast. The hardened material had excellent stability. Even after prolonged storage it shows no deterioration in photographic properties.

Example 3

With the same working method as in
but using 792 g

Example 2, potassium bi

carbonate, instead of sodium bicarbonate, was a 10 weight percent aqueous solution of the potassium salt of 2,4-dichloro-6-hydroxy-s-triazine.

5 ecm of this 10 percent strength by weight hardener solution was added to 1 kg of a chlorobromide silver photographic emulsion containing 80 g of gelatin and contained 10 g of the coupler of the following formula:

\ - CO - NHC ₁₇ H ₃₅
\ / \ f

SO ₃ H

The emulsion was adjusted to pH 7, cast on a cellulose triacetate film support and added Room temperature dried. The results are shown in the following table:

Melting points in water, C. 15 days 28 days Time after coating 32 32 4 days over 90 over 90 Without hardeners 32 Cured according to example 3 85

30th

After development in a developer containing 4-amino-3-methyl-N, N-diethylaniline, showed the hardened emulsion has the same photographic properties as an uncured emulsion, in particular regarding color density, sensitivity and fog.

Example 4

A solution of 92 g of trichloro-s-triazine in 300 ecm Dioxane was poured into 700 ecm cold water at 0 to 5 C with vigorous stirring so that a cyanuric chloride suspension resulted. At the same temperature became this suspension 1000 ecm of a 10 weight percent aqueous solution of tetramethylammonium hydroxide during one hour added dropwise. Stirring of this mixture was continued until a clear solution resulted. This solution was adjusted to a pH of about 8 and with Water made up to 2.41. The analysis showed that the solution was 5 percent by weight of the tetramethylammonium salt des 2,4-dichloro-6-hydroxy-s-triazine. 20 ecm of this solution were .1 kg of a 8% gelatin solution containing colloidal silver was added. With the resulting dispersion photographic paper was coated to produce a positive material for the silver salt diffusion process, to manufacture. After storage for 1 month at room temperature, the hardened gelatin layer not dissolved even in boiling water.

Example 5

A gelatin layer coated on a cellulose triacetate film backing became for 5 minutes in a 0.1 percent by weight, adjusted to pH 8 and 10 C aqueous solution of the sodium salt of 2,4-dichloro-6-hydroxy-s-triazines immersed. Then it was dried and 1 month at room temperature stored. The hardened layer could not be melted in water at 90 C, while an otherwise identical but uncured layer melted under these conditions at 32 ° C.

Claims (2)

Patent claims: 1. Process for hardening photographic gelatin layers by means of a 2,4-dichloro-s-triazine compound, characterized, that a compound of the general formula Cl-C Il C-Cl O-M is used in which M means alkali, alkaline earth or a quaternary ammonium group. 2. The method according to claim 1, characterized in that the in the manufacture of a 2,4-dichloro-6-hydroxy-s-triazine salt according to the invention by partial hydrolysis of trichloro-s-triazine resulting solution without prior isolation of the dichlorotriazine salt. if necessary after thinning, is used as a hardener solution.