US2030336A - Photographic developer - Google Patents

Description

Patented Feb. 11, .1936

PHOTOGRAPHIC DEVELOPER Heinrich Ulrich and Karl Saurwein, Ludwigs .hafen-on-the-Rhein,

Germany, assignors to Agfa Ansco Corporation, Binghamton, N. Y., a

corporation of New York No Drawing. Application December 22, 1933,

Serial No. 1932 7 Claims.

This invention relates to a photographic developer and more particularly to such a developer in which the usual alkali or the usual preservative or both have been replaced by compounds hitherto not known for this purpose.

One of its objects is to provide a developer in which the usual alkali and the preservative are replaced by a compound uniting both functions. A further object is to replace the usual alkali compo ds by compounds of which the alkalinity can be adjusted in a degree not hitherto known.

For certain purposes of photographic development it is desirable to have only a weakly alkaline developer in order to avoid drawbacks involved with the use of stronger alkaline developers.

According to this invention it has been found that the salts of hydroxyalkylamines with weak acids are excellently suited to replace for many purposes the alkali hitherto used in developers. The use of the salt of a weak acid of a hydroxyalkylamine involves the advantage that the alkalinity of the developer can be adjusted to any requirement. As hydroxyalkylamines which are suitable, there is mentioned, for instance, mono-, dior triethanolamine, propanolamine, butanolamine, oleylethanolamine, furthermore cyclohexylethanolamine, hydroxyethylmorpholine, hydroxyethylpiperidine, hydroxyethylethylenediamine, ethyldiethanolamine or the like, further the ethers or hydroxyethers obtainable from hydroxyalkylamines by etherification with alcohols or by reaction with ethylene oxide or the like. The substitution products of the amines enumerated likewise may be used. All ammonia derivatives. are suitable which contain in their molecule one or several alkyl radicals with one or several hydroxy groups, and, if required, contain still further aliphatic, cycloaliphatic or mononuclear aromatic radicals. Suitable weak acids are, for instance, carbonic acid and sulfurous acid. The salts of hydroxya'lkylamines with sulfurous acid present furthermore the advantage that they are capable to replace the preservative of the usual developers. Therefore, it is possible to produce photographic developers which contain besides the developing agent the sulfite of an hydroxyalkylamine which replaces both, the usual alkali and the preservative.

The salts of the hydroxyalkylamines with the weak acids are easily obtainable by reacting with the compounds on each other. If the acid is gaseous, for instance, in the case of sulfurous acid, the hydroxyalkylamine is saturated with the gas it the amine is liquid.

703,672. In Germany December 24,

The compounds enumerated above may, for instance, be added to the developing baths customary in the photographic industry, for instance, solutions of aminophenols, hydroquinone, hydroxyphenylglycine and the like. They may also be applied in combination with other substances suitable for the development of photographic plates, films and the like, for instance with sodium bisulfite, acetone bisulfite and the like. I

The-following examples serve. to illustrate the invention:

Example 1 Monomethylparaminophenol sulfate" I 2 grams Triethanolamine 5 cc. Triethanolamine sulfite 3 (:0. Water to 100 cc.

For use this solution is diluted by parts of water on one part of concentrated developer.

Example 2 Monomethylparaminophenol sulfate- 3 grams Triethanolamine sulfite 6 cc. Potassium bromide 0,2 gram Water to 500 cc.

Example 3 Water; 500 cc. Monomethylparaminophenol sulfate- 1,5 gram Triethanolamine 8 cc. Butanolamine sulfite 10 cc. Potassium bromide 1 gram Example 4 Water 500 cc. Monomethylparaminophenol sulfate- 0,3 gram Hydroquinone 0,4 gram Sodium carbonate sicc 4grams Ethanolcyclohexylamine sulfite 5 grams Potassium bromide 2 grams Our invention is not limited to the foregoing examples. Other weak acid salts of other hydroxyalkylamines maybe used and we contemplate as included within our invention all such modifications and equivalents as fall within the scope of the appended claims.

The term hydroxyalkylamine in the specification and the claims is intended to include amines containing at least one alkylhydroxy radical linked to the nitrogen atom of the amine.

What we claim is:

1. A photographic developer. comprising a developing agent and a weak acid salt of a hydroxyalkylamine.

2. A photographic developer comprising a developing agent and a weak acid salt of a hydroxyalkylamine selected from the group consisting of carbonates and sulfites.

3. A photographic developer comprising a developing agent and the sulflte of a hydroxyalkylamine.

4. A photographic developer comprising a developing' agent and a weak acid salt of a hydroxyalkyi-amine selected from the group consisting of monoethanol-amine, diethanol-amine, triethanol-amine, propanol-amine, butanolamine, oleylethanol-amine, cyclohexylethanolamine, hydroxyethyl-morpholine, hydroxyethylpiperidine, hydroxyethylethylene-diamine, and ethyldiethanol-amine.

5. A developer comprising monomethylparaaminophenol sulfate, triethanolamine, triethanolamine sulfite and water.

6. A developer comprising monomethylparaaminophenol sulfate, triethanol amine sulfite, potassium bromide and water.

'7. A developer comprising monomethylparaaminophenol sulfate, hydroquinone, sodium carbonate sicc., ethanol cyclohexylamine sulflte, potassium bromide and water.

HEINRICH ULRICH. KARL SAURWEIN.