Method Of Producing Photographic Images By Rapid Processing

Hofman , et al. March 7, 1

Patent Grant 3647460

U.S. patent number 3,647,460 [Application Number 05/038,483] was granted by the patent office on 1972-03-07 for method of producing photographic images by rapid processing. This patent grant is currently assigned to Gevaert-Agfa N.V.. Invention is credited to Henri Depoorter, Theofiel Hubert Ghys, Emiel Alexander Hofman.


United States Patent 3,647,460
Hofman ,   et al. March 7, 1972

METHOD OF PRODUCING PHOTOGRAPHIC IMAGES BY RAPID PROCESSING

Abstract

A rapid process for producing a photographic image is disclosed wherein the photographic silver halide element comprises as light absorbing antihalation or filter dye, a dye of the formula: ##SPC1## Wherein: p stands for 1, 2 or 3, Each of R.sub.1 and R.sub.2 is an aryl group, and M is a cation. The dye is very rapidly discharged upon processing of the exposed element and leaves no stains in the processed element. The dye is, therefore, particularly suitable for use in a photographic silver halide film element in which upon exposure a stable silver image is formed in the least possible time by "stabilization processing" which comprises developing the exposed element and treating the developed element with a stabilizing solution.


Inventors: Hofman; Emiel Alexander (Mortsel, BE), Ghys; Theofiel Hubert (Kontich, BE), Depoorter; Henri (Mortsel, BE)
Assignee: Gevaert-Agfa N.V. (Mortsel, BE)
Family ID: 10261880
Appl. No.: 05/038,483
Filed: May 18, 1970

Foreign Application Priority Data

May 30, 1969 [GB] 27,576/69
Current U.S. Class: 430/355; 430/405; 430/428; 430/513; 430/566; 430/963; 430/372; 430/421; 430/438; 430/523; 430/567
Current CPC Class: G03C 1/832 (20130101); G03C 5/26 (20130101); Y10S 430/164 (20130101)
Current International Class: G03C 5/26 (20060101); G03C 1/83 (20060101); G03c 005/30 (); G03c 001/84 (); G03c 001/06 ()
Field of Search: ;96/95,84,50,61,48QP,76,66I

References Cited [Referenced By]

U.S. Patent Documents
2274782 March 1942 Gaspar
3502474 March 1970 Tsuda et al.
Primary Examiner: Torchin; Norman G.
Assistant Examiner: Kelley; Mary F.

Claims



We claim:

1. Method of producing photographic images by rapid processing of an imagewise exposed photographic material comprising a transparent hydrophobic film support and a light-sensitive silver halide emulsion layer, wherein said photographic material comprises a water-permeable colloid layer comprising a dye corresponding to the following general formula: ##SPC9##

wherein:

p stands for 1, 2 or 3,

each of R.sub.1 and R.sub.2 stands for an aryl group, and

M stands for a cation.

2. Method according to claim 1, wherein said rapid processing includes a stabilization step and each of the processing steps wherein an aqueous processing liquid is applied takes less than 15 seconds at ambient temperature.

3. Method according to claim 2, wherein said rapid processing comprises in order a development step, a stabilizing step, a fixing step and a rinsing step.

4. Method according to claim 1, wherein said processing is carried out at a temperature of at least 30.degree. C. and each of the processing steps wherein an aqueous processing liquid is applied takes less than 1 min. at 30.degree. C.

5. Method according to claim 2, wherein said processing steps are carried out in an automatic processing apparatus in which the imagewise exposed photographic material is conducted from one processing station to the other.

6. Method according to claim 2, wherein each processing step lasts from 2 to 8 seconds.

7. Method according to claim 2, wherein the silver halide emulsion is a silver chloride emulsion, a silver chlorobromide emulsion, a silver chloroiodide emulsion or a silver chlorobromoiodide emulsion having at least 90 mole percent of silver chloride, the average silver halide grain size being comprised between 1 and 3 microns.

8. Method according to claim 1, wherein the light-sensitive material comprises (a) developing substance(s) in effective contact with the silver halide emulsion layer and/or in the latter layer itself.

9. Method according to claim 8, wherein said developing substances are hydroquinone and a 3-pyrazolidinone developing substance.

10. Method according to claim 1, wherein the total amount of developing substance(s) is present in the photographic material and the development is activated by means of an alkaline processing solution substantially free from developing substances.

11. Method according to claim 1, wherein the said water-permeable colloid layer comprises a dye corresponding to the formula: ##SPC10##

or an alkali metal salt or lead salt thereof.

12. Method according to claim 1, wherein the said water-permeable colloid layer comprises the following dyes: ##SPC11##

13. Photographic light-sensitive material suitable for stabilization processing comprising a transparent hydrophobic film support, at least one light-sensitive silver halide emulsion layer, a silver halide developing agent present either in the said emulsion layer or in a colloid layer in water-permeable relationship with the said emulsion layer and a water-permeable colloid layer which comprises a dye corresponding to the general formula: ##SPC12##

wherein:

p stands for 1, 2 or 3, each of R.sub.1 and R.sub.2 stands for an aryl group and

M stands for a cation.

14. Photographic light-sensitive material according to claim 13, which comprises hydroquinone and/or a 3-pyrazolidinone developing agent.

15. Photographic material according to claim 13, wherein said silver halide emulsion is a silver chloride emulsion, a silver chlorobromide emulsion, a silver chloroiodide emulsion or a silver chlorobromoiodide emulsion having at least 90 mole percent of silver chloride, the average silver halide grain size being comprised between 1 and 3 microns.

16. Photographic material according to claim 13, wherein said dye is the dye corresponding to the following formula: ##SPC13##

or an alkali metal or lead salt thereof.

17. Photographic material according to claim 13, wherein said water-permeable colloid layer comprises the dyes having the following formulas ##SPC14##
Description



The present invention relates to rapid processing of photographic light-sensitive material, especially to the use of light-absorbing antihalation or filter dyes in photographic materials that are subjected to rapid processing.

The normal processing of photographic materials involves the development of the exposed silver halide to a silver image, the treatment of the developed material with an acid bath in order to stop the development, the conversion of the unexposed silver halide to a soluble salt by fixation and the removal of the soluble silver salt formed by washing with water.

These various steps require a relatively long time and, therefore, various means have been proposed whereby the speed of processing can be enhanced. Disregarding the role of various ingredients, e.g., the role of developing agents that are incorporated into the photographic material in lieu of in the developing solution whereby development can be effected more rapidly, these means include the use of higher concentrations, the use of higher temperatures and the recourse to more intense agitations.

In order to enhance the processing speed without it being necessary to have recourse to the above measures of completing the various processing steps more quickly, the above normal processing can be modified e.g., in that one or more steps are combined or one or more steps are eliminated and other steps included. A very convenient modified method of photographic treatment which is nowadays widely employed for producing the photographic record in the least possible time and with a minimum of effort and equipment is the so-called "stabilization processing". By "stabilization processing" the unexposed and undeveloped silver halide is converted into light-inert complexes with the aid of a stabilizing solution containing stabilizing agents which obviate the necessity of subsequent washing. The fundamental difference between conventional and stabilization processing is, therefore, that whereas in the former the usual silver thiosulphate complexes formed during fixing must be washed out, in the latter the silver complexes are left in the emulsion.

In rapid processing, whether this is effected by the so-called stabilization processing or by other known techniques such as the use of highly concentrated processing solutions, the use of higher temperatures, the recourse to more intense agitations, etc., the photographic material owing to the short processing steps, which last generally less than 1 minute should meet various requirements which are not necessary in ordinary processing, wherein each of the processing steps lasts several minutes.

For instance, it is desirable to provide in photographic film material an antihalation layer situated on either side of the film support carrying the light-sensitive emulsion layer(s). It was observed that most of the antihalation dyes as commonly used in regular roll and sheet films which are completely and irreversibly decolorized and destroyed or removed during normal processing, are unsatisfactory for use in film material intended for being processed rapidly in that they leave stains in the processed material because they are not rapidly enough discharged or incompletely discharged in the too short lasting processing steps.

It has now been found that dyes corresponding to the following general formula: ##SPC2##

wherein:

p stands for 1, 2or 3,

each of R.sub.1 and R.sub.2 stands for aryl including substituted aryl such as aryl substituted by a halogen atom such as chlorine or by a carboxy or sulpho group in acid or salt form, and

M stands for a cation e.g., a hydrogen cation, a metal cation or an onium cation of inorganic or organic nature such as ammonium and pyridinium,

are completely and sufficiently rapidly discharged to be suitable for use in photographic materials that are subjected to rapid processing.

Thus the present invention relates to a method of producing photographic images by rapid processing an imagewise exposed photographic material comprising a transparent hydrophobic film support and at least one silver halide emulsion layer the said material comprising a water-permeable colloid layer containing a dye corresponding to the above general formula.

The dyes of use according to the present invention are particularly suitable for use in photographic material that will be processed by "stabilization processing" according to which each of the processing steps wherein an aqueous processing liquid is applied takes less than 15 seconds at ambient temperature. They are also suitable for use in photographic material that will be processed at increased temperature, say of at least 30.degree. C., by the normal steps of photographic processing, according to which each of the processing steps wherein an aqueous processing liquid is applied takes less than 1 minute at 30.degree. C.

The processing time referred to is the period of time elapsing from the beginning of a processing step to the end of this step i.e., when a stop-treatment or another processing step starts. This period of time mostly is somewhat longer than the period of time during which the processing liquid is really applied, except for the rinsing step which has to be considered as being finished when no further amount of aqueous rinsing liquid is supplied anymore.

Examples of particularly suitable dyes for use in accordance with the present invention are: ##SPC3##

The dyes of use according to the present invention can be incorporated into the colloid composition for forming an antihalation layer of a photographic material according to any technique known to those skilled in the art. The following is a mere description of some appropriate techniques:

An alkali salt of a dye according to the present invention is dissolved in water, whereupon the solution obtained is dispersed, occasionally in the presence of a wetting agent, in a hydrophilic colloid composition preferably a gelation solution. With a mixture so obtained, layers can be coated in which, in most cases, the dye is not fast to diffusion.

Layers with broad spectral absorption, in which the dye is fast to diffusion, can be obtained, provided the dye contains no sulphonic acid group, when one equivalent of a water-soluble salt, which forms water-insoluble salts with the dye, e.g., silver nitrate or lead nitrate, is added to the hydrophilic colloid composition before, during or after the addition of the aqueous solution of the alkali salts of the dyes.

The dyes according to the present invention that contain no sulphonic acid group can also be incorporated when using a dispersion of said dye in a hydrophilic colloid, obtained in one of the following ways:

a. a solution of the dye, in its free carboxylic acid form, in a suitable organic water-miscible and/or water-immiscible solvent, is dispersed in a hydrophilic colloid solution, preferably an aqueous gelatin solution, occasionally in the presence of a wetting agent. For more details about such dispersing techniques, there can be referred to United Kingdom Pat. Spec. Nos. 791,219 filed Nov. 9, 1955 by Kodak 1,098,594, 1,099,414, 1,099,415, 1,099,416 and 1,099,417 all filed Jan. 25, 1965 by Gevaert-Agfa N.V., to United States Pat. Spec. No. 2,304,940 of Leopold D. Mannes and Leopold Godowsky, Jr., issued Dec. 15, 1942, to French Pat. No. 1,555,663 filed Oct. 20, 1967 by Gevaert-Agfa N.V. and to Belgian Pat. No. Spec. 722,026 filed Oct. 9, 1968 by Gevaert-Agfa N.V.

b. a suspension of the dye in water is finely ground in a mill, e.g., a colloid ball mill, occasionally in the presence of a wetting agent; the hydrophilic colloid can be added before or after the milling process.

The colloids or mixtures of colloids used in the hydrophilic colloid compositions, into which the dyes are dispersed, may be of any type as commonly used in photographic materials, e.g., gelatin, casein, polyvinyl alcohol, poly-N-vinyl pyrrolidone, carboxymethyl cellulose, sodium alginate, etc., gelatin being however favored. Before coating, other ingredients such as coating aids and hardening agents, may be added to the composition of the antihalation dyes of use according to the invention.

The light-sensitive material for use in carrying out the method of the present invention may be whatever type of light-sensitive silver halide material.

Various silver salts may be used as light-sensitive salt, e.g., silver bromide, silver iodide, silver chloride or mixed silver halides e.g., silver chloro-bromide, silver chloro-iodide, silver bromoiodide and silver chlorobromoiodide.

It is also possible that two or more silver halide emulsion layers are present which depends on the kind of the reproduction system involved. The silver halide emulsion layers may comprise all kinds of ingredients usual in the art, e.g., developing compounds such as hydroquinone, a 3-pyrazolidinone developing compound and a p-aminophenol developing compound or mixtures of at least two of these three types of developing compounds, further preservatives for developing compounds, development accelerators, stabilizing agents, fog inhibitors, sensitizers, color couplers, hardeners or latent hardeners which are effective in an alkaline medium only, softening agents, latices, matting agents, coating aids, etc. On top of the photographic material a protective layer may be provided as generally known in the art.

Preferably the method of the present invention is carried out in an automatic compact processing apparatus in which the photographic material may be guided automatically and at a constant speed from one processing unit to the other in such a way that the processing time in each processing unit does not last longer than 15 seconds at room temperature in the case of stabilization processing and not longer than 1 minute at 30.degree. C. in the case of conventional processing at increased temperature at least above 30.degree. C. The processing liquids may be applied according to whatever technique known in the art, e.g., by dipping the photographic material in the processing liquid, or by applying this liquid by means of a licking roller, by spraying, or from a pod which is ruptured at the moment the processing liquid has to be spread all over the photographic material. In carrying out the method of the present invention in an automatic processing unit it is also possible to keep the photographic material motionless and to apply the successive processing liquids automatically. The exposure unit may form part of the processing apparatus or may be mounted separately.

Although the present invention is concerned with whatever type of rapid processing of photographic black and white or color material, comprising a transparent hydrophobic supporting member and a silver halide emulsion layer, it relates especially to the formation of black-and-white images by the so-called "stabilization processing" system.

For a comprehensive survey of stabilization processing of photographic material and of the stabilizing agents suitable for use in said processing in order to form with the unexposed silver halide light-inert silver complexes that need not be washed out, there can be referred to A. A. Newman, "The Chemistry of Stabilization Processing" Brit.Jl.Phot., 1009, 1967 as well as to the literature referred to therein.

Stabilization processing usually comprises only a development station and a stabilizing station. This two-bath stabilization processing is particularly suitable when quick results are more important than negatives or positives or archival stability. Indeed, since according to the two-bath stabilization processing no washing takes place the images obtained still comprise chemical components such as the developing agents used either in oxidized or unoxidized form; the dyes used for extending the spectral sensitivity of the silver halide material, the silver complexes formed during the stabilization treatment, etc. These components may be subject to degradation and produce stain on ageing particularly in the high-light areas of the image.

Therefore, in order to obtain really permanent copies it is possible to include a post-stabilization treatment such as a normal fixing station followed by a rinsing station. Fixing and rinsing which in normal processing last several minutes can here be reduced to some seconds.

The dyes of use according to the present invention are particularly suitable for use in photographic film material that will be processed by the two-bath stabilization processing, which may be followed by common fixing and rinsing.

Therefore, the preferred embodiment of the method of the invention for producing photographic images by rapid processing comprises the steps of treating an imagewise exposed light-sensitive material comprising a transparent hydrophobic film support, a rapidly developable silver halide emulsion layer and an antihalation layer containing a dye corresponding to the above general formula situated on either side of the support i.e., either on the emulsion side of the support or on the back of the support, with a solution effecting development of the exposed silver halide and with a stabilizing solution by which the residual unexposed silver halide is converted into a light-inert silver complex. This preferred embodiment of the method of the present invention may further include the steps of treating the developed and stabilized image with a common fixing solution followed by rinsing.

A stabilization processing method comprising the successive steps of developing stabilizing, fixing and rinsing the imagewise exposed silver halide material has been described in our copending United Kingdom Pat. application 46,444/67 filed Oct. 11, 1967 by Gevaert-Agfa N.V. According to this what can be called four-bath stabilization processing it is possible to produce in a rapid way, say in less than 1 minute, photographic images with archival stability.

As compared with conventional processing, the method according to copending United Kingdom Patent application 46,444/67 filed Oct. 11, 1967 by Gevaert-Agfa N.V. possesses the advantages of providing permanent copies more rapidly. By the insertion of the stabilization step before the fixing step, the fixing time can be reduced considerably i.e., to a few seconds where otherwise fixing takes several minutes at ambient temperature.

In accordance with the invention the successive processing stations of the preferred embodiment of the method of the invention are arranged in such a way that at a constant transporting speed of the light-sensitive material the processing time lasts from 1 to 15 seconds and preferably from 2 to 8 seconds for each of the processing liquids used. This means that when the method of the invention wherein a light-sensitive material is used having an antihalation layer comprising a dye corresponding to the above general formula is for instance based on the above four-bath stabilization processing, the total processing time is always comprised between 4 and 60 seconds, which is properly low, even with respect to the maximum processing time. The total processing time can even be reduced by applying generally known techniques for accelerating photographic treatments, e.g., by raising the temperature of at least one of the processing liquids, preferably the developing or development activating liquid and/or the fixer.

More details as regards the preferred embodiment of the method of the invention and the photographic materials used will be given hereinafter.

The photographic material of use according to the method of the present invention comprises at least one silver halide emulsion layer. As noted above various silver halides may be used as light-sensitive silver halide. However, in stabilization processing the silver halide emulsion layer(s) is (are) preferably pure silver chloride emulsions or silver chloro-bromide or silver chloro-bromo-iodide emulsions having at least 90 mole percent of silver chloride and having an average silver halide grain size which is comprised between 1 and 3 microns. An emulsion layer of this type is characterized in that the latent image produced on imagewise exposure is fully developed within 10 seconds upon contact of the solution effecting development with the imagewise exposed silver halide grains. Increasing the development energy by applying generally known techniques such as raising the temperature and the pH value of the said solution and enlarging the concentration of the active ingredients of the said solution, does not substantially effect the development rate of this type of silver halide emulsion layer.

Silver halide emulsions with a rather strong gradation for the reproduction of line work may be used as well as silver halide emulsions having a softer gradation and being suited for the reproduction of continuous tone originals.

The silver halides are dispersed in the common hydrophilic colloids e.g., gelatin, casein, polyvinyl alcohol, carboxymethyl cellulose, alginic acid, etc., gelatin being however favored.

The silver halide emulsion layer, preferably being a gelatino silver halide emulsion layer, is applied to a common photographic film support of a transparent hydrophobic synthetic polymeric material e.g., a cellulose triacetate support, a polyester support such as a polyethylene terephthalate support, etc. The support may be provided with one or more suitable subbing layer(s) for ensuring a good adherence of the light-sensitive silver halide emulsion layer to the support.

An antihalation layer comprising a dye corresponding to the above general formula is provided either on the back of the support or on the side carrying the light-sensitive silver halide emulsion layer(s). When the antihalation layer is situated between the emulsion layer(s) and the support the said antihalation layer may serve as subbing layer for the silver halide emulsion. In addition to the antihalation dyes corresponding to the above general formula other rapidly decolorizable antihalation dyes may also be provided in the said antihalation layer. For instance, for this purpose the dye marketed under the name PANGELB by Farbwerke Hoechst, A.G., Frankfurt, W.-Germany and having the following formula: ##SPC4##

has been found particularly suitable.

The light-sensitive material may further comprise one or more auxiliary layers such as an antistatic layer, a protective layer, etc. It is also possible, in order to obtain an increase of the gradation and of the maximum density of the image produced as well as a sensitivity gain of the reproduction system involved, to provide between the support and the emulsion layer(s) one or more intermediate hydrophilic colloid layers having a total weight comprised between 2 and 8 g. per sq.m.

This or one of these hydrophilic intermediate layers may serve as carrier for the antihalation dyes of use according to the present invention. For more details as regards this hydrophilic intermediate layer there can be referred to our copending United States Pat. application 814,165 filed Apr. 7, 1969 for "Method of producing photographic images by rapid processing".

The light-sensitive material may further comprise any kind of usual ingredients. Into the silver halide emulsion layer and/or in another colloid layer in water-permeable relationship with the said emulsion layer preferably at least part and even the total amount of developing substance(s) is incorporated, often together with a preservative for said developing substance(s). By incorporating the total amount of the developing agents in the photographic materials themselves in lieu of the developing solution, development can be activated by means of a mere alkaline activator bath, which by the absence of developing agent(s) is better keepable.

In accordance with the present invention, there is therefore also provided as novel composition light-sensitive silver halide film material comprising a film support, at least one light-sensitive silver halide emulsion layer, a silver halide developing agent present either in the said emulsion layer or in a colloid layer in water-permeable relationship with the said emulsion layer and an antihalation layer comprising a dye corresponding to the above general formula which is situated on either side of the said film support.

Developing substances that have proved to be especially suitable for the purpose of the present invention are hydroquinones and 3-pyrazolidinone developing compounds. These types of developing compounds are generally known in the art and thus need no further explanation. Preferably both types of developing compounds are incorporated into the light-sensitive material together. Mostly hydroquinone and/or an alkylated hydroquinone is applied in an amount of from about 200 mg. to about 3 g. per sq.m, and the 3-pyrazolidinone developing compound in an amount of from about 50 to about 400 mg. per sq.m. The hydroquinone developing compound is mostly incorporated into the silver halide emulsion layer itself; the 3-pyrazolidinone developing substance preferably is incorporated into the silver halide emulsion layer and/or into a layer on top of the silver halide emulsion layer. Normally also preservatives for the developing substances present are incorporated into the light-sensitive material. As suitable preservatives may be mentioned water-soluble organic and inorganic bisulphites such as formaldehyde-bisulphite and potassium metabisulphite.

Other common ingredients incorporated into the light-sensitive material are sensitizers (chemical and/or optical), hardeners, softening agents, development accelerators, preservatives, antistaining agents, latices, dispersing agents, etc.

For instance, the light-sensitive emulsion may be chemically as well as optically sensitized. They may be chemically sensitized by effecting the ripening in the presence of small amounts of sulphur containing compounds such as allyl thiocyanate, allyl thiourea, sodium thiosulphate, etc. The emulsions may also be sensitized by means of reductors for instance tin compounds as described in French Patent No. 1,146,955 filed Apr. 11, 1956 by Gevaert Photo-Producten N.V. and in Belgian Pat. No. 568,687 filed June 18, 1958 by Gevaert Photo-Producten N.V., imino-amino methane sulphinic acid compounds as described in United Kingdom Pat. No. 789,823 filed Apr. 29, 1955 by Gevaert Photo-Producten N.V., and small amounts of noble metal compounds such as of gold, platinum, palladium, iridium, ruthenium and rhodium. Further the light-sensitive emulsions may be sensitized by addition of development accelerators as for example compounds of the polyoxyalkylene type such as alkylene oxide condensation products as described among others in United States Pat. No. 2,531,832 of William Alexander Stanton, issued Nov. 28, 1950 and U.S. Pat. No. 2,533,990 of Ralph Kingsley Blake, issued Dec. 12, 1950, in United Kingdom Patent Nos. 920,637 filed May 7, 1959, 940,051 filed Nov. 1, 1961, 945,340 filed Oct. 23, 1961 all three by Gavaert Photo-Producten N.V., 991,608 filed June 14, 1916 by Kodak and in Belgian Patent No. 648,710 filed June 2, 1964 by Gevaert Photo-Producten N.V., and onium derivatives of amino-N-oxides as described in French Patent No. Spec. 1,498,724 filed Oct. 3, 1966 by Gevaert-Agfa N.V.

According to the preferred embodiment of the method of the present invention the light-sensitive material after imagewise exposure which may occur by means of an exposure station which is either coupled to the processing station or wholly separated therefrom, may be transported automatically and at a substantially constant speed for processing e.g., by means of rollers and guideways.

First, it may be transported through a developing or activating station. Such a station may consist of a tray containing the developing or activating liquid through which the light-sensitive material is transported, in other words the light-sensitive material may be wetted by dipping. The developing or activating liquid can also be applied by means of a lick-roller taking up said liquid on its surface and applying it uniformly to the whole emulsion side of the light-sensitive material. The developing or activating liquid may also be comprised in a kind of bottle from which again and again an accurately measured amount is supplied to the light-sensitive material, e.g., by spraying or by uniform spreading. Further, the developing or activating liquid may be contained in a pod, which is embodied in the light-sensitive material or applied hereto later on, and which at the development stage is ruptured, so that the content is uniformly spread over the part of the photographic material to be developed. The term developing or activating station is thus very broad and encompasses any way of effecting the development of the light-sensitive material.

Also the stabilizing station as well as all possible further treating stations have to be taken in their broad sense. For a detailed description of different suitable practical embodiments for these processing stations reference is made to the detailed description given hereabove with respect to the developing or activating station. For the processing time in each of the processing stations there can be referred to the detailed description given hereinbefore.

The development applied in carrying out the preferred embodiment of the method of the present invention is preferably an energetic surface development. The high energy is required in order to allow the development to proceed quickly and may be obtained by properly alkalizing the developing or activating liquid (pH 10-12), and/or by using (a) high-energy developing substance(s) or a combination of developing substances, which as a consequence of their superadditive action is very energetic such as a combination of a hydroquinone and a 3-pyrazolidinone developing substance as already referred to above. The concentration of the alkaline substance(s) and developing substance(s) in the developing liquid is generally known in the art and needs no further explanation. Suitable alkaline substances for the developing or activating liquid are sodium hydroxide, sodium carbonate, trisodium phosphate and strong organic alkaline substances. The developing or activating liquid further may comprise usual ingredients such as preservatives, compounds releasing halide ions, toning agents and thickeners, so that a developing or activating paste may be obtained.

The stabilizing liquid for carrying out the next processing step in the preferred embodiment of the method of the invention is an aqueous liquid containing a suitable stabilizing agent. By "stabilizing" agent any compound is understood that is capable of converting light-sensitive silver halide grains in substantially light-insensitive complexes, which are water-insoluble or substantially water-soluble. As noted above, these light-inert complexes need not be removed from the developed and stabilized silver halide emulsion layer by subsequent washing. However, if desired the water-soluble complexes may be removed by washing. Suitable stabilizing agents of the class that forms water-insoluble light-insensitive complexes with silver halide grains are compounds belonging to the general class of compounds represented by the general formula RSH, wherein R is any aliphatic, aromatic, or heterocyclic radical. Compounds of this class include thioglycolic acid, monothiohydroquinone, thiosalicylic acid, etc. Suitable stabilizing agents that form substantially water-soluble complexes with silver halide are thiosemicarbazide, acetylthiourea, sulphonated thiourea, sulphonated thiosemicarbazides, allylthiourea, and water-soluble thiocyanates. The water-soluble thiocyanates more especially potassium and ammonium thiocyanate are the best suited compounds for the purpose of the present embodiment. The stabilizing solution is an aqueous solution comprising preferably from about 20 to about 300 g. of stabilizing agent per liter. Preferably this solution is slightly acidified. The stabilizing solution may furthermore contain any usual ingredients such as a preservative for the image produced etc.

By the development or activating station and the stabilization station a fully developed and stabilized print is obtained in less than 30 seconds but as noted above, in order to obtain really permanent copies the stabilization station may be followed by a common fixing station and a rinsing station.

The treatment in a fixing station comprises a treatment with an aqueous fixer i.e., an aqueous solution of a compound forming with silver halide water-soluble complexes, which can be easily and completely removed from a developed silver halide emulsion layer by normal washing. Suitable fixing agents are the water-soluble thiosulphates especially ammonium thiosulphate and sodium thiosulphate. The fixing agent is mostly present in an amount of from 50 to 300 g. per liter of fixer. Just as the stabilizing solution the fixer in most cases is slightly acidic. It may comprise some further ingredients such as sulphites and bisulphites.

The rinsing station serves to eliminate the silver halide complexes formed. This is mostly done by means of water, preferably common tap water to which a calcium-sequestering compound has been added, e.g., the trisodium salt of ethylenediamine-tetraacetic acid, demineralized or distilled water which may contain wetting agents. Rinsing can proceed according to any usual technique.

For the treatment in the various processing stations the imagewise exposed silver halide material is preferably transported automatically and at a substantially constant speed. During this transport the successive processing steps are carried out. In addition to the above four processing steps, other pretreatments, intermediate treatments or after-treatments may be applied in carrying out the preferred embodiment of the present invention. So a development-stopping treatment may be inserted. It is often advantageous to eliminate the surplus liquid in one or more of the processing steps, e.g., by means of a doctor knife or a pair of pressure rollers between which the light-sensitive material is led. After rinsing, the light-sensitive material may be dried, e.g., by means of a device blowing hot air; or by bringing the material is contact with a heated plate. In most cases, however, no additional treatments are carried out and the total processing remains limited to the processing steps described above. The processing stations may be arranged separately but mostly are grouped in a compact unit wherein the light-sensitive material is automatically carried from one unit to another at a constant speed. Preferably the units just consist of a tray containing the liquid through which the light-sensitive material is transported.

The following examples illustrate the present invention.

EXAMPLE 1

A cellulose triacetate film support was provided at one side with a gelatin antihalation layer comprising dyestuff 2 and at the other side with a gelatin-cellulose nitrate subbing layer, a gelatin intermediate layer having a dry weight of 4.0 g. per sq.m, a light-sensitive gelatin silver halide emulsion layer containing hydroquinone and 1-phenyl-3-pyrazolidinone and a gelatin antistress layer comprising 1.5 g. of gelatin per sq.m.

The antihalation layer was coated from a solution having the following composition:

gelatin 80 g. dyestuff 2 2.5 g. 40 % aqueous formalin 2 ml. 10 % aqueous saponine 20 ml. water to make 1 liter

This composition, after adjustment of the pH to 6.0 was coated pro rata of 50 g./sq.m. so that 4 g. of gelatin and 0.125 g. of dyestuff were present per sq.m.

The silver halide emulsion used was a rapidly developable silver chlorobromoiodide (98 mole percent chloride, 1.8 mole percent bromide and 0.2 mole percent iodide) emulsion having an average grain size of about 1.8 micron and a ratio of gelatin to silver nitrate of 0.75 and comprising as spectral sensitizer the dye having the following structural formula: ##SPC5##

It was applied in such a way that per sq.m 2 g. of hydroquinone, 0.3 g. of 1-phenyl-3-pyrazolidinone and an amount of silver halide equivalent to 5.0 g. of silver nitrate were present.

The light-sensitive material was imagewise exposed to a line original whereupon it was guided in a compact automatic processing unit at a constant speed in order through the following two processing solutions at room temperature:

1. Acticator liquid sodium hydroxide 30 g. sodium sulphite 50 g. potassium bromide 2 g. water to make 1000 ml.

2. Stabilizing liquid ammonium thiocyanate 250 g. sodium metabisulphite 20 g. water to make 1000 ml.

sulphuric acid to adjust the pH to 4.5.

The total time of processing was about 10 seconds. A fully developed and stabilized print was obtained; the colored antihalation layer was completely and irreversibly decolorized.

EXAMPLE 2

A photographic film material was prepared as described in example 1, with the difference that now the dye having the following formula: ##SPC6##

the antihalation layer was coated from a solution having the following composition:

gelatin 80 g. dyestuff 1 0.5 g. dyestuff 2 2.5 g. Pangelb 2 g. 40 % aqueous formalin 2 ml. 10 % aqueous saponine 20 ml. water to make 1 liter

This composition, after adjustment of the pH to 6.0 was coated pro rata of 50 g./sq.m. so that 4 g. of gelatin, 25 mg. of dyestuff 1, 125 mg. of dyestuff 2 and 100 mg. of Pangelb were present per sq.m.

The material was exposed and processed as described in example 1 with the difference that the following two additional processing solutions were included:

3. A fixer sodium thiosulphate 200 g. potassium metabisulphite 25 g. water to make 1000 ml.

4. A rinsing liquid consisting of demineralized water.

The total processing time was 16 seconds (i.e., 4 seconds for each of the processing liquids).

A permanent and nontacky print was obtained; the antihalation layer was completely and irreversibly decolorized.

EXAMPLE 3

A photographic film material was prepared as described in example 1, with the difference that now the antihalation layer was coated from a solution having the following composition:

gelatin 80 g. dyestuff 5 (added from a 2 % dispersion in 2 % gelatin prepared by means of a swinging mill) 6 g. 40 % aqueous formalin 2.5 ml. 10 % aqueous saponin 15 ml. water to make 1 liter

The composition, after adjustment of the pH to 6.0, was coated pro rata of 50 g./sq.m. so that 4 g. of gelatin and 300 mg. of dyestuff 5 were present per sq.m.

The material was processed as described in example 2. The antihalation layer was completely and irreversibly decolorized.

EXAMPLE 4

A subbed polyester support was provided with a layer of the same composition as described in example 3.

The material obtained was processed at 35.degree. C. in the following way:

1. Treatment for 22 seconds with the following developing composition (pH 11.05 ):

water 800 ml. potassium hydroxide 40 % 80 ml. anhydrous potassium carbonate 20 g. potassium metabisulphite 40 g. hydroquinone 12 g. 1-phenyl-3-pyrazolidinone 1 g. potassium bromide 2 g. water to make 1,000 ml.

2. Rinsing for 22 seconds.

3. Fixing for 25 seconds in an aqueous composition comprising per liter 20 g. of sodium bisulphite and 170 g. of ammonium thiosulphate (pH 5.2).

4. Rinsing for 50 seconds.

The antihalation layer was completely and irreversibly decolorized.

EXAMPLE 5

A series of antihalation layers were coated on a film support. Each layer contained per sq.m 4 g. of gelatin and an amount of antihalation dye as listed in the table below. The antihalation layers were processed either as described in example 1 (processing A: "two-bath stabilization processing"), or as described in example 2 (processing B: "four-bath stabilization processing"), or as described in example 4 (processing C: conventional "rapid processing" at increased temperature).

The percentual residual staining, measured at .lambda. max. of the dystuff, listed in the table below, was determined:

1. directly after processing, and

2. except for processing C, after storage for 5 days at 20.degree. C. and 90 percent of relative humidity. ##SPC7## ##SPC8##

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