US2682464A - Method of packaging and stabilizing single-powder developers - Google Patents

Description

June 29, 1954 E. s. wnTALA ETAL 2,682,464

METHOD OF PACKAGING AND STABILIZING SINGLE-POWDER. DEVELOPERS Filed June 26, 1952 SINGLE POWDER PHOTGAPH/C DEI/LOPER Edwin S. Wiz' fala DonaldJKridel INVENToRs ATTORNE YS UNITED STATE TENT OFFICE METHOD OF PACKAGING AND STABILIZING SINGLE-POWDER DEVELOPERS Edwin S. Wiitala and Donald J. Kridel, Rochester, N. Y., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of `New Jersey Application June `26, 1952, Serial No. 295,782

6 Claims. (Cl. 95-88) This invention relates to single-powder photographic developers, and more particularly to a method of' packaging and stabilizing the singie-powder mixture to prevent disadvantageous interaction between the organic developer component and the basic component of the` singlepowder mixture.

Single-powder developer mixtures may `contain an organic developer component or mixtures of such components, including monomethyllo 2,605,118 of August 5, 1952, the effective and imparaaminophenol sulfate (elon or metol), hyproved stabilization of single-powder photodroquinone, p-aminophenol hydrochloride, pgraphic developers is accomplished by intimateaminophenol sulfate, pyrogallol, parahydroxyly mixing boric anhydride With the other comphenyl glycine, catechol, diaminophenol hydroponents of the single-,powder developer mixture. chloride and others, with an alkali component, a We have now found a unique way of employstabilizing component, an oxidizing preventer ing boric anhydride to stabilize the same type andan anti-fogging component. The alkali of single-powder photographic developers withcomponent may be the stable hydrate of an alout actually incorporating the boric anhydride kali carbonate, a desiccated alkali carbonate, an stabilizer into the mixture. alkali metaborate, or analkali suliite. Generally An object, therefore, of the present invention the stable alkali carbonate monohydrate is preis a novel method of stabilizing single-powder ferred. The oxidation preventing` component photographic developers with boric anhydride. may be an alkali sulte, and the anti-fogging Another object of this invention is a nc-vel component may be potassium bromide or iodide. method of packaging and a novel package for Stabilizing components for such a single-powder single-powder photographic developers. developer are disclosed in Patent 2,384,592 of Other objects will appear hereinafter. September l1, 1945, and include maleic anhy- In accordance with the present invention we dride, salicylic acid, alkali metabisulte, benzoic have found an alternative method of employing anhydride, orthobenzoic sulfamide, phthalamide boric anhydride to stabilize single-powder phoand phthalic anhydride. The latter has outtographic developers as well as a novel method standing stabilizing properties in the presence for packaging such powders in a novel package. of either sodium carbonate or borax and has We have found that instead of incorporating been employed considerably more than the other the powdered boric anhydride as the stabilizing stabilizers mentioned in that patent. component into thephotographic developer rnix- While the stabilizing effect of the phthalic anture, the same beneficial stabilizing eiect may hydride is very good, it has been employed most be achieved by fusingl an equivalent amount of successfully in developer compositions having as boric anhydride onto the inside of the container the Valkali component either sodium carbonate in which the single-powder developer is to be or. sodium suli'lte, or mixtures thereof. Less subsequently packaged. This is a surprising dissuccesc has been attained in the case of the 40 coveryand although the theory of its operation lfl'QOltlt CllSS 0f develODSlS Containing sodium is not completely understood it nevertheless is meahorate as the alkali ingredient- AISO, the an effective method for preserving single-powder presence of phthalic anhydride in the Singledevelopers against self-deterioration. powder developer involves other considerations our method may be employed with glass and which are not too desirable. metal containers and with plastic or other types In the irst place, phthalic anhydride is slowly soluble in water. Furthermore, it is impossible to employ it in the presence of benzotriazole, the latter being a desirable component of certain developer mixtures. But the greatest disadvantage of employing phthalic anhydride in single-powder developer mixtures, which contain alkali carbonates and suli'ite, is that phthalic anhydride may react, due in part to temperature effects with these basic substances and forni gas under suiicient pressure to distend the hermetically sealed can in which the developer powder is packaged, and often cause a portion of the powder to be ejected with some violence as the package is opened.

ln the. copending application by William J. Rogers, Serial No. 210,284, filed February 9, 1951, entitled stabilizing Agent for Single Powder Photographie Developers now U. S. Patent of containers which will withstand the heat necessary to fuse the boric anhydride. An effective procedure to fuse the boric anhydride onto the inner surfaces of the container, is to dust the desired amount onto the inner surfaces of the container which has been heated somewhat above the fusing temperature of the boric anhydride. The fused coating may, however, be formed by placing the boric anhydride on the surface and subsequently heating the container to the fusing temperature, or by flowing molten boric anhydride onto the surfaces to be coated. As soon as the fusion takes place, or the surface is coated with the molten substance, the container is cooled to normal temperatures to set the coating. The single-powder photographic developer is then added to the container and the cover sealed thereon in accordance with the usual practice in this art. An amount of boric anhydride up to of thetotal weight of the other constituents may be employed effectively. No particular advantage is found when a larger amount is employed.

The following examples will serve further to illustrate the method of packaging and stabilizing single-powder developer mixtures according to our invention:

Example 1 A metal can was heated to 577 C. and 4.2 grams of -boric anhydride was sprinkled over the interior surface of the can. The hot can caused the boric anhydride to become lmolten and ow in a thin coating over the inner surface of the can. The can was then cooled to room temperature and the fused coating adhered thereto.

A thoroughly mixed single-powder photographic developer composition comprising:

Grams Elon (monomethyl p-amino phenol sulfate) 5.1 Anhydrous sodium sulte 45.0 Hydroquinone 12.0 Sodium carbonate monohydrate 81.3 Potassium bromide 1.9

Example 2 A glass bottle was heated to 557 C. and the inner surface sprinkled with 2.2 grams of boric anhydride which became fused to the can surface. After cooling to room temperature a thoroughly mixed single-powder photographic f developer composition comprising:

Grams Sodium sulte 50 Sodium carbonate monohydrate 54 Potassium bromide 1 Pyrogallol 6.4

was placed in the coated bottle and sealed therein. On exposure to extremes of temperature in the vicinity of 100 F. it was found that the boric anhydride effectively stabilized the single-powder against disadvantageous chemical reaction. The powder then was used successfully as a developer. A check sample stored in an untreated bottle was very badly deteriorated.

Example 3 A glass bottle was heated to 577 C. and a coating of 2.9 grams of fused boric anhydride formed thereon as explained herein.

To the cold bottle was added a single-powder photographic developer composition containing:

Sodium carbonate monohydrate 54.0 Potassium bromide 1.0

The bottle was sealed and exposed to a temperature of F. for ten hours. The single-powder was then employed in a, developing process and was found to be unchanged and to have undiminished developing properties. A 4check sample in an uncoated bottle showed evidence of deterioration under similar treatment.

In preparing a developer solution, the compositions of the above examples should be dissolved in water to make one liter of solution.

In the accompanying drawing there is sho-wn an elevation View in section of a container comprising a body l0 and a tight fitting cover H. The inner walls of the container have a coating l2 of fused boric anhydride thereon. A singlepo'wder photographic developer is shown as I3.

By our novel process the advantages of employing a boric anhydride stabilizer actually mixed in the single-powder developer as shown in Patent 2,606,118, supra, can be attained by merely coating the inside of the container with a fused boric lanhydride coating. This unexpected discovery permits single-powder mixtures having highly reactive ingredients to be stabilized against reaction without actually mixing the boric anhydride stabilizer throughout the powder.

We claim:

1. The method of stabilizing a single-powder photographic developer composition containing an organic silver halide developer and a photographically compatible basic ingredient selected from the group consisting of alkali sulfit-es and carbonates which comp-rises packaging the developer composition in a closed container having a coating on the interior surface thereof of fused boric anhydride.

2. The method of stabilizing a single-powder photographic developer composition containing an organic silver halide developer, an alkali carbonate, and an alkali sulfte which comprises packaging the developer composition in a closed container having a coating on the interior surface thereof of fused boric anhydride.

3. The method of stabilizing a single-powder photographic developer composition containing monomethyl p-'aminophenol sulfate, hydroquincne, anhydrous sodium sulte, sodium carbonate monohydrate and `potassium bromide which comprises packaging the developer composition in a closed container having a coating on the interior surface thereof of fused boric anhydride.

4. The method of stabilizing a single-powder photographic developer composition containing monomethyl p-aminophenol sulfate, hydroquinone, anhydrous sodium sulflte and potassium bromide which comprises packaging the developer composition in a closed container having a coating on the interior surface thereof of fused boric anhydride.

5. The method of stabilizing a single-powder photographic developer composition containing pyrogallol, sodium sulte, sodium carbonate monohydrate and potassium bromide which comprises packaging the developer composition in a closed container having a coating on the interior surface thereof of fused boric anhydride.

6. The method of stabilizing a single-powder References Cited in the le of this patent photographic developer composition containing UNITED STATES PATENTS parahydroxy phenyl glycine, sodium sulte, sodium carbonate monohydrate and potassium Number Name Date bromide which comprises packaging the developer 5 11591399 Walker July 5, 1926 composition in a closed container having a ooat- 2,058,250 Nltafldy OC- 20: 1936 ing on the interior surface thereof of boric 2:6061118 Rogers Aug 5 1952 anhydride- OTHER REFERENCES lo Mellor, "Comprehensive Treatise on Inorganic and Theoretical Chemistry, Vo1.'5, 1924, page 41.

Claims (1)

1. THE METHOD OF STABILIZING A SINGLE-POWDER PHOTOGRAPHIC DEVELOPER COMPOSITION CONTAINING AN ORGANIC SILVER HALIDE DEVELOPER AND A PHOTOGRAPHICALLY COMPATIBLE BASIC INGREDIENT SELECTED FROM THE GROUP CONSISTING OF ALKALI SULFITES AND CARBONATES WHICH COMPRISES PACKAGING THE DEVELOPER COMPOSITION IN A CLOSED CONTAINER HAVING A COATING ON THE INTERIOR SURFACE THEREOF OF FUSED BORIC ANHYDRIDE.

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