DE4413893A1 - Use of indolenine cyanine dyes - Google Patents

Description

The present invention relates to the use of Indolenine cyanine dyes as infrared absorbing Agents in photographic recording materials and Photographic prints containing indolenine cyanine dyes drawing materials.

Photographic recording materials generally have mean a multi-layer construction. Infrared sensitive Silver halide based materials contain one or several colloid layers with one or more infrared absorbing dyes, which u. a. the Ab sharpness of the recording material can be increased should. These dye-containing layers can in ver different positions within the multilayer materials are used, but color can also be used layers of substance on the back of a photograph material to suppress blurring effects applied by reflection of scattered light (anti halo layers). It is also already known Dye directly into the photosensitive, silver halo to bring in colloid layers containing genides.

Suitable dyes must have a suitable absorption possess characteristic during the photographic wet processing are completely decolorized, and they have to be easily out of the photographic material be washed so that the developed material none Has residual color after processing. In addition, should there is no coloring of the baths.

It is known, especially for those sensitive to infrared photographic silver halide materials infrared absorber dyes of the heptamethine cyanine type  Indolenine end groups (US 48 76 181, EP-A 445 627) or bridged and substituted indolenine cyanines (US 49 33 269, EP-A 350 026) to use. This color however, fabrics meet the requirements not or only partially. For example, they will during the photographic processing process only are slowly and / or imperfectly discolored and / or synthetically difficult, d. H. only with a considerable increase wall and associated costs, accessible. In the event of of Benz [e] indolenine cyanines must also from cancer producing 2-naphthylamine can be assumed.

There is therefore a need for infrared absorbing paint substances that are easily accessible synthetically, the have a suitable infrared absorption and a sufficient decolorization during the photographic Have processing.

It has now surprisingly been found that certain Indolenine cyanine dyes meet these conditions. These dyes are already known as such (CA 119 (20): 205990v and CA 108 (4): 29398v); the invention proper use is not yet part of the stand of the technique.

The present invention thus relates to the use of dyes of the general formula I

wherein
R¹ and R² independently of one another hydrogen, hydroxy, (C₁-C₄) alkoxy, amino, (C₁-C₄) alkylamino, di- (C₁-C₄) - alkylamino or halogen and
M⊗ a cation
mean as an infrared absorbing agent in photographic recording materials based on silver halide.

(C₁-C₄) alkyl groups can be straight-chain or branched and mean, for example, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl and tert-butyl. Methyl, ethyl and n-propyl are preferred. Halogen means in particular fluorine, chlorine, bromine and iodine, chlorine being preferred,
R¹ and R² are preferably hydrogen.

Cations representing M⊗ are preferably monovalent Cations, with alkali metal cations as well as substituted Ammonium ions and the ammonium ion itself especially before are moving.

M⊗ is very particularly preferably the sodium ion, the potassium ion, the ammonium ion and the triethylammonium ion.

In the use according to the invention, the colors substances of general formula I preferably in amounts of 5 to 500 mg / m², particularly preferably 20 to 200 mg / m² used.

The dyes of the general formula I can in one are obtained in a manner which is known per se, at for example by implementing a corresponding substi did 2,3,3-trimethylindolenine with 2-chloroethane sul fonyl chloride and glutacondialdehyde, which is usually in Form of its Dianil hydrochloride is used.  

For example, the dye of the general formula I in which R¹ and R² are hydrogen and M⊗ is the triethylamonium ion is obtained as follows:
4.0 g of 2,3,3-trimethylindolenine and 4.5 g of 2-chloroethanesulfonyl chloride in 30 ml of acetic acid are heated under reflux for 2 h. The mixture is then evaporated to dryness in vacuo and the residue obtained is taken up in 30 ml of acetic anhydride. Then 2.8 g of glutacondi aldehyde dianil hydrochloride and 5 ml of triethylamine are added. The reaction mixture is heated under reflux for 5 min, cooled to 20 ° C. The dye is separated and dried. The dye is obtained as a dark powder. λ _max = 742 nm (water).

The present invention also relates to photographic Silver halide-based recording materials which are characterized in that they are a dye of general formula I as an infrared absorbing agent contain.

The recording materials according to the invention have in usually a multi-layer structure, the color Substance of the general formula I in every position can be used within the material. Prefers in the photosensitive, containing silver halides Colloid layer, or in separate hydrophilic Colloidal layers, e.g. B. in an antihalation layer.

The named coloid layers consist, for example, of Polyvinyl alcohol, carboxymethyl cellulose, sodium alginate, Casein, polyvinyl pyrrolidone, but preferably made of gelatin. The materials mentioned can also in any mixtures with each other can be used.  

As a rule, the colloid layers also contain other aids, for example casting additives, mesh agents or hardeners (see e.g. Research Dis closure, vol. 308, 1989, item 308 119).

The dye of general formula I is in the package layers preferably in amounts of 5 to 500 mg / m², particularly preferably contain 20 to 200 mg / m².

The dyes of the general formula I can be in easier, known manner in the fiction, ge moderate recording material or a colloid layer work. For example, the dyes are in one suitable solvents, especially water or alcohol fetch like As ethanol, dissolved and then optionally in the presence of a wetting agent and / or further pouring agent sets in the above material, preferably gelatin, brought in. The casting solutions obtained in this way can then in layer form by methods known per se worn (see e.g. "Science and Technology of Photography ", Karlheinz Keller (Ed.), VCH publishing house total mbH., Weinheim 1993).

The dyes of the general formula I can be Easily incorporate photographic material, lend it a suitable absorption characteristic crazy during the photographic development process completely discolored and easily accessible synthetically.

Crucial for the advantages compared to the according State of the art dyes are the two N-sulfoethyl groups. Longer sulfoalkyl groups surprisingly lead to significantly worse bleachability and washout behavior, which can only be achieved by leadership of further sulfo groups could be compensated.  

But this would be an unacceptably high syn lead to theoretical effort.

example

Casting solutions of the following composition were obtained represents:

Inert gelatin: 12 g
Sodium dodecyl sulfate: 10 ml of a 1% aqueous solution
Formaldehyde: 10 ml of a 5% aqueous solution
Water: 188 ml
Dye: 40-80 mg.

The following were used as dyes:

• A: Dye of the general formula I with R¹ and R² = Hydrogen and M⊗ = HNEt₃⊗ (according to the invention)
• B: dye of the formula State of the art)
• C: dye of the formula (State of the art)

The solutions were combined in a conventional manner cast a carrier provided with an adhesive layer. The Absorp tion maxima and the optical densities of the obtained Gelatin layers were as follows:

The gelatin layers obtained were subjected to the following photographic processing process:
Development in a conventional Metol-Hydroquinone developer at 20 ° C. for 2 minutes, subsequent treatment in a conventional fixing bath (containing sodium thiosulfate and sodium disulfite) for 5 minutes and subsequent rinsing with water for 10 minutes and subsequent drying.

The residual stains were assessed visually, the following Results were obtained:

Claims (8)

1. Use of dyes of the general formula I wherein
R¹ and R² independently of one another are hydrogen, hydroxy, (C₁-C₄) alkoxy, amino, (C₁-C₄) alkylamino, di- (C₁-C₄) alkylamino or halogen and M⊗ is a cation, as an infrared absorbing agent in photography silver halide-based recording materials. 2. Use according to claim 1, characterized in that R¹ and R² are hydrogen. 3. Use according to claim 1 and / or 2, characterized ge indicates that M⊗ for the sodium ion, the potassium ion, the ammonium ion or the triethylammonium ion is. 4. Use according to one or more of claims 1 to 3, characterized in that the dyes of general formula I in amounts of 5 to 500 mg / m² be used. 5. Photographic recording material on silver halo genid base, characterized in that it is a color Substance of the general formula I as claimed in claim 1 contains infrared absorbing agent.   6. Photographic recording material according to claim 5, characterized in that the dye of the general Formula I contained in a hydrophilic colloid layer is. 7. Photographic recording material according to claim 6, characterized in that the hydrophilic colloid layer consists of gelatin. 8. Photographic recording material according to claim 6 and / or 7, characterized in that the dye of general formula I in the hydrophilic colloid layer in Amounts of 5 to 500 mg / m² are included.