US2380809A - Color couplers for photographic color development - Google Patents

Description

July 31, 1945 OFFICE 001103 COUPLEBS FOR PHOTOGRAPHIC Y COLOR DEVELOPMENT Honore Verkinderen, Morisel, and Norbert Vankeirsbilok, Lenven, Belgium: vested in the Alien Custodian Property No Drawing.

This invention relates to photographic color development and to processes of color development for use in connection with color photography.

It is known that color photographic images may be formed by using a developer which iorms a colored and insoluble oxidation product during development, the colored product thus formed scribed a process of color development by means oi compounds oi the general formula:

. Y-rCHri-B where Y is one of the electro-negative groups CR- or 2.00- (wherexis anelhior aryl group, substituted or unsubstitimd) while B is an arylor hctcrocyclo-substitutcd amino roup.

the invention are compounds having the general formula: "Ii "if --on|-x wherein In an electro-negative such as acyl-, cyano-etc.. and

Yisanorganicradicalfsuchashydrogemalkyl oraryLthelasttwomaybcsubstitutedor unsubstituted.

0 schen Gesellschait" 22, (1889) page 2414. The

40 forming color photographic images by the incor- Applicatlon April 18, .1841, Serial In Great Britain December 11,

A 2 Claims. ((31. 95-88) Examples of such couplers are:

8 bensyi-il aoetonyl-1,8,4-oxodissolo 'Ihese color couplers, on coupling with the oxidation product oi an aromatic-amino-developerduring the development of the latent image, form a yellow wlor when belonging to the class as illustrated by Example 1, and an orange color when belonging to the class as illustrated by Example 2.

These compounds are prepared by the method described in Berichte der Deutschen Chemi- .compou nd of Example 2 is prepared by reactin cuprous cyanide with 3-phenyl-5 chloroacetyl- 1,2,4 oxodiaaole which can be obtained by the process described in Berichte" 18 (1886) page The present invention consists, broadly, in the process of producing color-photographic images by the use of color couplers as above defined.

Thus the invention comprises the process of poration, in the photographic emulsion, before or after coating, of a color coupler as above deiineii and, further. the process of developing a latent photographic image by means of a color developer comprising in addition to an aromatic amino developing agent a color. coupler as above defined.

Thus the invention includes the method of color development which comprises developing a latent photographic image by means 01' an aromatic amino developer in the presence of color couplers as above defined, and eliminating the silver image which is formed during development so that a clear and transparent color image remains.

The invention also consists in new or improved color iorming developers comprising, in addition to an aromatic amino developing agent, color couplers as above, defined.

The present invention .iurther includesphoto- 2 l s,sso,soc

graphic elements having at least one layer con- B essentially of the product resulting from the taining maker and transparent image composed cm-C c-N coupling in situ during development of color couplers as above defined, with the oxidation 5 K Cnhco product of an aromatic amino developing agent.

The aromatic amino compounds which may be uethmol' "com" 100 used as developing asents in the present inventlon include the mono-, diand tri-amino-aryl- For m B to compounds. Among the mono-amino developing Rosanna 4 agents may be mentioned amino-phenols and amlno-cresols and their halogen derivatives and 4 amino-naphthols. I i

The developing agents preferably used and g pan phenylened e g 3 having hitherto given the best results in connecl5 s u tion with the present invention are the aromatic fi fi g zgfl'i "g" :3 orthoand para-diamines. such as para-phenyl- 7 sodium hydroxide 2 enedlamine and its substitution products. These water h" 1000 developing agents may be substituted in one aminogroup'orintheringorinbothJormingzo 3 compounds such as: NR diethyl-para-phenylenedlamine. N I

Mi mmum QE, .C Q .CH' "I" 3 para-phenylenediamine, and n. v S-amlno-B dlmethylamino-tolume.

These compounds are usually kept in the salt 100 form such as hydrochloride or sillllhlte. For B 'dded The following developer solutions may be used mu 5 togiveacolorimageaecordingtcthepreaentao invention: A

N-N' diethyl-para-phenylenediamine 4 n01 5 2 1m diethyl-para-phenylenediamine odiu m v ust --s-- m g g Sodium carbonate (cryst) g 80 Sodium sulphite (cryst.) g-.. as Sodium hvdmflde --s-- 2 Sodium carbonate (cmt) e so Weter Sodlumhydroxide g 2 3 Water mm 1000 40 B C---N CaHr-C-N 1k )i-om-co-cm a -cm-oo-om g s 0 Methanol Mm 100 Methanol m 100 l'bruse B is ldded toA. For use 8 is added to A. Foams 8 Ibnmu 2 w A A N-N' diethyl-para-phenylenediamine v S-amino-Q 'dimcthylamino-toluene hydro- H01 I 2 chloride ..g- 4 vSodium sulphite (crystJ g 25 Sodium sulphite (crvst.)---. g- 10 Sodium carbonate (cry t) 3-- 60 Potassiumcarbouate g 50 Sodium hydroxide g 2 Sodium hydroxide g 3 Water 'm 1000 Water mm... 1000 B B CaHa-CN 00 -r r 28-OHg-r-CN 5 I%\o/ JCHrC0GHs g.. 8

o Methanol ccm 100 Methanol Mm 100 n u d m lbl'unalltddutob.

mom 3 Forms 7 A A N-N diethyl-para-phenylenediamine N-N diethyl-para-phenylenediamine H01 3;. 2 RC1 g 2 Sodium sulphite (ct-yet.) as Sodium sulphlte (cl-yet.) ..gts carbonate (crystJu -g 00 Sodium carbonate (crystJ ..g.. Sodium hydroxide g 2 Sodium hydroxide g 2 Water 7 1 com 1000 Water y can" 1000 Organic solvents, for instance acetone, alcohols or the like, may be used to dissolve the color couplers.

The invention is in no way limited to the use oi the color couplers in the developing solution itself.

Thus as above stated, one o! the essential products, the color coupler, which during the development forms the dye, can also be added to the photographic emulsion (for instance by adsorption upon the silver salts) before or after coating. The other ingredients of the color forming baths, containing chiefly the aromatic amino developer, may be applied later, during the developing process. as a bath.

The present invention may be utilized in the formation of colored photographic images on plates or papers as well as on films, employing gelatine or some other carrier substance :lor the silver halide.

The developing process may be used for developing photographic material, provided with one or more sensitive layers, which are, applied on one side or on both sides of the support.

The silver formed during the developing process may be eliminated. For this purpose a bath should be used, however, which does not destroy the dye. Thus, a bath consisting of a solution in water of potassium ferricyanide and sodium thiosulphateeasily eliminates the silver without destroying the dye, leaving a pure dye image.

We do not wish to be limited to the exact details of the invention as described in the foregoing specification as various modifications will occur to a person skilled in the art.

We claim:

1. The process of developing a colored image in a. gelatin-silver halide photographic layer which comprises coupling the development product of a primary aromatic amino developing compound with the coupler compound, 3 benzyl-5 acetonyll,2,4-oxodiazole 2. The process of developing a colored image in a gelatin-silver halide photographic layer which comprises coupling the development productof a primary aromatic amino developing compound with the color coupler compound of the general formula wherein X is an electro-negative organic radicalselected from the class consisting of acyl and cyano, while Y is an organic radical of the class consisting of substituted alkyl.

HONORE VERKINDEREN, NORBERT VANKEIRSBILCK.