US 3811888 A
Description (OCR text may contain errors)
nited States Patent 1191 Shibaoka et a1.
1451 May 21, 1974 Filed: Feb. 3, 1972 Appl. No.2 223,374
Foreign Application Priority Data Feb. 3, 1971 Japan 46-4126 US Cl. 96/66 R, 96/66.4 Int. Cl G03c 5/30 Field of Search 46/60, 61, 50, 66, 62,
References Cited UNITEDSTATES PATENTS 7/1965 Luckey et al. 96/6l R 3,586,631 Fassbender 96/50 3,634,088 1/1972 Cooley 96/50' 3,658,535 4/1972 Willems 96/60 3,467,521 9/1969 Frank 96/66.2
OTHER PUBLICATIONS Chaberek & Martel], Organic Sequestering Agents, 1959, p. 156.
Primary ExaminerRonald H. Smith Assistant Examiner-M. F. Kelley Attorney, Agent, or Firm-Sughrue, Rothwell, Mion, Zinn & Macpeak  ABSTRACT Composition for processing a silver halide photographic light-sensitive element containing ethylenebis(,B'0xyethylamine) tetraacetic acid or its alkali salt. The compound has a calcium ion-chelating or masking ability superior to that of EDTA.
I 9 Claims, No Drawings 1 COMPOSITION FOR PROCESSING SILVER HALIDE PHOTOGRAPHIC LIGHT-SENSITIVE ELEMENTS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a processing composition for use in processing a silver halide photographic lightsensitive element. More particularly, the invention is concerned with such a processing composition containing a chelating agent for the calcium ion present in a hardening, stopping or stabilizing. In effecting these processings, the processing agents used in each processing are generallyusedvas an aqueous solution, so that the properties of each processing composition vary largely withthe quality of the water used. For instance,
water which contains a high calcium ion content, i.e., so.called hard water, reacts with carbonates, sulfites, borates or like salts present in the processing agents to form water-insoluble calcium salts. Such calcium salts adhere to the photographic light-sensitive element to be processed (this is called the production of scum), and the solidified calcium salts mayinjure the emulsion layer of the photographic light-sensitive element. Furthermore, the calcium salts may be deposited in the processing apparatus, ultimately causing breakdown of the apparatus.
In an attempt to eliminate such defects, it has been proposed to mask the calcium ion, and, as the calcium masking agentthere is known a polyphosphate such as sodium tetrapolyphosphate, aminopolyacetic acid or a salt thereof, ethylene diamine tetraacetic acid or a salt thereof, and thelike. I
These known calcium masking agents are, however,
' all insufficient to be. used in photographic processing compositions. For instance, although the polyphosphate has'an excellent masking ability, the ability is reduced when used in an alkaline processing composition due to conversion of the polyphosphate toorthophosphate. 4
Ethylene diamine tetraacetic acid (EDTA) or its alkali salt is atpresent considered the most excellent calcium masking agent, but, when added to a processing composition containing an organic reducing agent such as a developing agent, it willaccelerate the oxidation of the organic reducing agent such as a developing X 0 O CH: C
N CH3CH2 O-CHzCI-Ir OCH1CH1N XOOCHIC CHQCOOX wherein X stands for a hydrogen atom or an alkali metal atom such as sodium or potassium.
DETAILED DESCRIPTION OF THE INVENTION Since the above-described compound is in the form of a powder, it may be added directly into a processing solution, or added prior to the preparation of the processing solution to'the processingagents in the form of a powder. Accordingly, as herein used, the term composition of processing agents includes the processing agents in the form of both liquid and powder.
The calcium masking agents according to the present invention show in particular remarkable effect when added into a composition of photographic processing agents containing an organic reducing substance such as a developing agent, although they may be added into any composition of photographic processing agents which contains calcium ions, for example, hard water. Such compositions of processing agents include fixing solutions, bleaching solutions, hardening solutions, stopping solutions and stabilizing solutions. Formulation of each composition of processing agents is in no way limited so far as the composition'has its function, because the effect of the compounds of the invention is basically connected with the calcium-containing water itself. Although the fore-going description of the agent, thereby reducing the stability thereof. Such a phenomenon. is inparticular prominent when iron is present in the processing composition.
SUMMARY OF THE INVENTION One object of the present invention is to provide a composition of processing agents for use in processing invention has been made with particular reference to the calcium-containing water, it will be apparent that the same effect is encountered when other liquids containing calcium ionsare used as a solvent for the processing agents.
The amount of the compound according to the invention is in the rangeof from 0.1 to 10, preferably from 0.5 to 3g. per liter of photographic processing solution.
The present composition of photographic processing agents as herein described and hereinafter claimed may be applied to solutions for processing black and white photographic light-sensitive elements including X-ray films, lith-films, microfilms, printing paper and the like, and color photographic lightsensitive elements.
The'present invention will be'further explained by the following examples.
Example 1 As the auto-developer for a direct X-ray film for medical use there was prepared a liquid composition of the following formulation.
Formulation of developer Anhydrous sodium suli'ite 40.0 g Hydryquinone 30.0 g l-phenyl-3-pyrazolidone L5 3 Potassium hydroxide 22.0 g Anhydrous potassium carbonate 15.0 g
CHzCOOX -Continued Formulation of developer Glutaraldehyde Potassium bromide l -phenyl-5-mercaptotetrazole Water to make I liter we e oper C. The amount of calcium carbonate which could V be dissolved in the respective Developers A to C was as follows.
Developer Amount 'of calcium carbonate dissolved A 0.03 g. B 0.36 g. C 0.12 g.
As is evident from the results, the calcium ions can be masked by the Developer B according to the present invention and the affect of calcium ions can be reduced to one third that in the Developer C containing EDTA.
Example 2 Using Developers A to C in Example 1, the difference in hydroquinone-oxidation velocity between the case of solutions containing a low iron ion content and the case of a high iron ion content was investigated. The oxidation of hydroquinone was carried out under the same conditions in every case by air-oxidation. The air-oxidation was effected at room temperature using vessels in which the surface area of the developer surface in contact with air and the volume of the developer were identical in every case, thereby effecting a natural air-oxidation. The results are shown in the following table.
Developer Amount of oxidized hydroquinone (g./l)
In the absence of In the presence of 20 iron ions mg./l of iron ions A l0.l l2.l B I05 I03 C 17.0 21.6
As is evident from the above results, oxidation occurs with more difficulty in the case of the developer according to the present invention in comparison with the developer containing EDTA, even in the presence of iron ions.
Example 3 to the method described in Example 2. The exposure, development, measurement of photographic density and the like were all effected in a conventional manner, using the same conditions in every case.
Properties Developer A Developer B Developer C Fog 0.06 0.06 0.04
'Relative speed l00 98 SI at fog-density plus 1.0
photographic density Maximum 3.30 3.45 3.00
density mazz) Contrast 2.30 3.45 3.00
Example 4 Ammonium thiosulfate 150.0 g. Anhydrous sodium sulfite 15.0 g. Boric acid 10.0 g. Acetic acid aqueous solution) 23.0 c.c. Anhydrous aluminum sulfate 9.0 g Water to make I liter Into a fixing solution of the above-described formulation there was dissolved calcium carbonate and white turbidity was observed at a concentration of 4 g/l calcium carbonate. When 4 g/l of calcium carbonate was added into a fixing solution having added thereinto 2.7 X 10 mole of ethylenebis(,B-oxyethylamine)tetraacetic add, no white turbidity was observed, which clearly shows the fact that the ethylenebis(fioxyethylamine) tetraacetic acid has a calcium ion masking effect in fixing solutions.
Example 5 Formulation of Developer D Para-amino-N,N-diethylaniline sulfate 2.0 g. Anhydrous sodium sulfite 2.0 g. Sodium carbonate monohydrate 60.0 g. Hydroxylamine hydrochloride 0.5 g. Potassium bromide 0.4 g.
Water to make I liter After oxidizing each of Developers D to F for a given time by the method described in Example 2, the amount ofthe developing agent oxidized thereby was determined, the results being shown in the following table.
As isevident from the above-described table, prevention of developing agent oxidation by means of the compound of the invention is superior to that by using EDTA.
This invention has been described in considerable detail with particular reference'to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described hereabove and as defined in the appended claims. 7
What is claimed is:
l. A developing composition comprising a black and white or color silver halide developing agent and a sequestering agent, wherein the improvement comprises said sequestering agent being at least one of ethylene bis(beta-oxyethylamine)tetraacetic acid and its alkali metal salts at a level such that when a developing solution is formed from said composition, said ethylene bis-' beta-oxyethylamine)tetraacetic acid or its alkali metal salts are present at a level of from 0.1 to 10 g. per liter of said developing solution.
2. A developing composition as claimed in claim 1, wherein said alkali metal salt is a sodium or potassium salt.
4. A developing composition as claimed in claim 1 which is in the form of a liquid.
' 5. A developing composition as claimed in claim 1 wherein said solution is an aqueous solution.
6. A developing composition as claimed in claim 1, wherein said developing agent is a hydroquinone or a phenylene diamine developing agent.
7. A method for preventing the air oxidation of an aqueous photographic developing composition containing a black and white or color developing agent for an exposed silver halide element by the addition of a ous solution contains iron ions.
3. A developing composition as claimed in claim 1 which is in the form of a powder.