US3443940A - Diffusion transfer employing ringclosure to release color-providing material for transfer - Google Patents

Description

May 13, 1969 s. M. BLooM `.ET AL 3,443,940

DIFFUSION TRANSFER EMPLOYING RING-CLOSURE T() RELEASE COLOR-PROVIDING MA'I'ER'IIAL FOR TRANSFER Filed July 24, 1967 4N Y@ SUPPORT A '2` ,\,A X, COLOR-PROVIDING MATERIAL '0 /Z/QMSILVER -mILIOI EMuLsION '6 "77- r-n-TTLT'PROCESSING COMPOSITION '8 .IMAGE-RECEIVING LAYER 20 j /ff/////// vSUPPORT F I G. l

I4F SUPPORT aof-nY/Y/Y///f `-SIIPPORT F I G. 3

Isv 1,.; O /L. L L] L L- -PROCESSING COMPOSITION Ie/ ,f ;-IMAGEREcEIvINO ELEMENT 20,4/ L C SUPPORT INvENTORs F G 4 l @5ML/15M@ Mam BY *Nomad 1 f/wmm :fj M OGu/m JOM ATTORNEYS United States Patent 3,443,940 DIFFUSION TRANSFER EMPLOYING RING- CLOSURE TO RELEASE COLOR-PROVID- ING MATERIAL FOR TRANSFER Stanley M. Bloom, Waban, and Howard G. Rogers,

Weston, Mass., assiguors to Polaroid Corporation, Cambridge, Mass., a corporation of Delaware Filed July 24, 1967, Ser. No. 655,440 Int. Cl. G03c 7/30 U.S. Cl. 96-3 34 Claims ABSTRACT OF THE DISCLOSURE This invention relates to color photography wherein novel systems are provided for obtaining, as a function of development of an exposed photosensitive element, a differential in diifusibility or mobility of a colorproviding material, whereby an imagewise distributori of more moble color-providing material may be transferred, by imbibition, to a superposed sheet material to provide thereon a color transfer image.

BACKGROUND OF INVENTION Many systems are known for preparing color images by diffusion transfer. In such prior systems, for example, a photosensitive element containing at least one lightsensitive silver halide emulsion and associated layer of color-providing material, e.g., a complete dye or a color coupler, is exposed and then developed to provide, as a function of development, an imagewise distribution of color-providing material which is transferred, by imbibition, to a superposed image-receiving element, e.g., a dyeable sheet material, to provide thereon a monochromatic or multicolor image of the original subject matter. Many of these prior systems rely for color transfer image formation upon mechanisms for providing, as a function of development, a differential in mobility or diffusibility in the processing fluid of the color-providing material.

Various systems have also heretofore been suggested wherein the color-providing material contains an anchoring moiety or ballast rendering this material immobile or non-diffusible and the chemistry of reaction as a function of development is such that the color-providing moiety is separated from the anchoring moiety so that it is free to transfer to the image-receiving element to form a color transfer system.

The present invention involves various new systems and procedures of the foregoing description utilizing compounds including a color-providing moiety and an anchoring moiety, wherein the color-providing moiety is freed to transfer, as a function of development, thereby providing an imagewise differential of transferable colorproviding material.

SUMMARY According to the present invention, a photosensitive element including at least one light-sensitive silver halide emulsion is developed in the presence of a compound which is immobile and non-diffusible in the processing fluid, but which, upon development, undergoes an imagewise ring-closing reaction to split off a mobile and diffusible color-providing material which is transferred, by imbibition, ot a superposed dyeable stratum to form thereon a color transfer image.

These compounds may be defined as being compounds which are immobile and non-diffusible in an aqueouss alkaline processing medium and which are capable of reacting with an oxidized color developer or which are Capable of providing an oxidation product which may auto-react intramolecularly in such a way as to form ICC a new heterocyclic ring and, as a function of such reaction, to split off a mobile and dilfusible color-providing material.

As used herein and in the appended claims, the terms mobile or diffusible are given their ordinary meaning in the art and denote the property of the material of being mobile or diffusible in the processing composition; whereas the terms immobile or non-diffusible are also given their art-accepted meaning and denote the converse property of the material.

The present invention contemplates various systems utilizing such compounds to form either a positive or a negative color transfer image.

BRIEF DESCRIPTION OF DRAWING FIGURE 1 is a partially schematic, partially enlarged fragmentary sectional view illustrating one previously exposed photographic product of this invention during processing thereof;

FIG. 2 is a partially schematic, partially enlarged fragmentary sectional view illustrating another photographic product of this invention;

FIG. 3 is a view similar to that of FIGURE 1 of another photographic product of this invention; and

FIG. 4 is a view similar to FIG. 2 of still another photographic product of this invention.

PREFERRED EMBODIMENT In the preferred embodiment, the color-providing moiety is a complete dye moiety and image formation is effected by selective transfer of this dye moiety, by imbibition, to a superposed dyeable stratum to form thereon, depending upon the system employed, either a positive or a negative dye transfer image.

As was mentioned previously, this invention relates to photography, and more particularly to novel processes and products for preparing color transfer images.

A primary object of this invention, therefore is to provide novel processes and products for preparing color images by diffusion transfer.

Another object is to provide novel systems for obtaining, as a function of development of an exposed photosensitive element, a differential in diffusibility or mobility of a color-providing material, whereby an imagewise distribution of more mobile color-providing material may be transferred by imbibition to a superposed sheet material to provide a color transfer image thereon.

A further object is to provide novel systems for obtaining either a positive or a negative color transfer image, utilizing novel compounds which, upon development, undergo a chemical reaction to release for transfer a mobile and dffusible color-providing material.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the several steps and the relation and order of one or more of such steps with respect to each of the others, and the products possessing the features, properties, and the relation of elements which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in conjunction with the accompanying drawing.

According to the present invention, the aforemetioned objectives are accomplished by providing a photosensitive element including at least one light-sensitive silver halide emulsion having associated therewith a compound which is immobile and non-dilfusible, but which upon development undergoes a ring-closing reaction to split off a mobile and ditfusible color-providing material. Color image formation is predicated upon the resulting differential in diffusibility, whereby an imagewise distribution of the more diffusible color-providing material split olf as a function of development may be transferred to an image-receiving layer, e.g., a dyeable stratum of the character heretofore known in the art, to provide a color transfer image thereon.

As was mentioned previously, the immobile and nondiffusible compounds employed in association with a lightsensitive silver halide emulsion in the practice of this invention maybe defined as compounds which are capable of reacting with an oxidized color developer or which are capable of providing an oxidation product which may auto-react intramolecularly in such a way as to form a new aromatic or heterocyclic ring and as a function of such reaction and ring formation to split off a mobile and diffusible color-providing material.

They may also be defined as being within one of the following groups of compounds:

(l) Relatively immobile and non-diffusible compounds capable of coupling with the oxidation product of an aromatic primary amino color developer during development of an exposed silver halide emulsion with subsequent ring closure to produce a new heterocyclic ring and as a function of such reaction to split oi a mobile and diiusible color-providing material; or

(2) Relatively immobile and non-diffusible silver halide developing agents which are capable of providing, upon development or reduction of silver halide, an oxidation product which can auto-react intramolecularly to form a new heterocyclic ring and las a function of such reaction to split oi a mobile and diffusible color-providing ma- The compounds of the foregoing description may -be represented by the following formula:

wherein: A represents the atoms necessary to complete an aromatic ring, e.g a benzene or naphthalene nucleus, which nucleus may be further substituted; D is a colorproviding moiety, e.g., a complete dye such as a monoazo, disazo or anthraquinone dye, which may, if desired, be metallzed in known manner; Z may -be hydrogen, any of the substituents heretofore known in the art which are replaceable by oxidized aromatic amino color developer in so-called elimination-coupling reactions (see, for example, Mees, The Theory of the Photographic Process, revised edition, 1954, pp. 599-601), e.g., chloro, bromo, carboxy, sulfo, hydroxy, alkoxy, hydroxyalkyl, etc.; or an aromatic amino radical, e.g., an anilino substituent, including substituted anilino radicals, particularly of the p-hydroxyanilino series or the substituted anilino radical or a color developer of the p-phenylene diamine series, e.g.,

where each R2 is hydrogen or a lower alkyl radical, and including the known substituted derivatives of the aforementioned anilino radicals having a free position ortho to the -NH- substituent, a para-amino or a para-hydroxynaphthylamino radical, including substituted derivatives thereof having a free position ortho to the NH- substituent, which derivatives may contain an anchoring moiety to be described with more particularity hereinafter; Y is any substituent which completes or forms an amide with, and reduces the basic character of the amino group in the 3-position, such as the residue of an acid, linking the color-providing moiety D to the -nitrogen atom, and which is capable of being eliminated during the ring 4 formation to be described with more particularly hereinafter, eg.,

is -im -ilo-t lower alkyl wherein each R3 may be hydrogen, hydrocarbon radical, c g., alkyl, such as methyl, ethyl, butyl, dodecyl, etc., aryl such as phenyl or naphthyl attached through a carbon atom thereof to the nitrogen atom, a cyclic alkyl such as cyclopentyl or cyclohexyl, i.e., where both R3s are alkylene comprising together with the nitrogen atom a heterocyclic ring, a substituted alkyl, such as hydroxyethyl, methoxyethoxyethyl, polyglycoloxyethyl, carboxymethyl, carboxyethyl, ethylcarboxymethyl, benzyl, phenylethyl, sulfophenylethyl, acetylaminophenylethyl, succinylaminophenylethyl furanemethyl, etc.; or a substituted aryl such as methylphenyl, ethylphenyl, etc.; or when Z is one of the described anilino or naphthylamino radicals containing a para-amino or para-hydroxy substituent, X may be hydrogen; or the substituent R; R is an anchoring or immobilizing substituent rendering the compound nondiffusible, eg., higher alkyl such as decyl, dodecyl, stearyl, oleyl, etc. linked directly to the aromatic nucleus or linked indirectly thereto through an appropriate linking group, e.g., -alkylene-CONH, CONH-,

etc., an aromatic ring, e.g., of the benzene or naphthalene series, or a heterocyclic ring, which rings may be either bonded to a single carbon atom of the aromatic nucleus or fused thereto, i.e., bonded to a pair of adjacent carbon atoms, or R may be a plurality of short chain radicals which together provide the anchoring moiety, each of said short chain radicals being linked directly or indirectly to a different carbon atom of the aromatic nucleus formed by the A moiety; R1 is hydrogen, an alkyl such as methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl, cyclohexyl, etc.; or a substituted alkyl such as 2-hydroxyethyl, 3-dihydroxypropyl, carboxymethyl, carboxyethyl, car-boxybutyl, car- 'boxydecyl, hydroxyethyl-ether, polyglycoloxyethyl, furanemethyl, benzyl, phenylethyl, carboxyphenylethyl, sulfophenylethyl, acylamino-phenylethyl, etc.; and n is a positive integer from 1 to 2 provided that when R1 or R3 alone or together comprise one of those named substituents rendering the compound non-diifusible, i.e., an anchoring substituent, and/or when Z comprises an aromatic nucleus contributing an anchoring moiety alone or in conjunction with said R1 and/ or R3 moieties, n may be l, but when R1, R3 or Z alone or together do not provide such a substituent, n must be 2. i

The various substituents described above Ywhich may provide the R, R1, R2, R3, Z and/or Y moieties and illustrative compounds containing the same are disclosed, for example, in one or more of the following U.S Patents: 2,414,491; 2,486,440; 2,522,802; 2,536,010; 2,543,338; 3,227,550; 3,227,551; 3,227,552; 3,227,554; 3,243,294; and 3,245,795.

In general, compounds within the scope of Formula A may be readily synthesized by approprite reaction between 6 an acid salt of the desired dye and the 3-amino substituent of the aromatic ring, as follows:

l l R ,5 R Rtf1-1i A l 7. Rui-1i A l z -N- H c1: -Y--n a -N-Y-D Where X is amino, it may be necessary or desirable to 1t) (2) 0H employ the corresponding l-nitro analogues in the aforementioned reaction followed by reduction, e.g., with hyo (13H1 drogen in the presence of a Rancy nickel catalyst, to form a l-amino compound within the scope of Formula -lT-"-N=N A. It may also be desirable, in some instances to have the 15 1L H o 1amino substituent protected during reaction, eg., by 1' Ha H CONHCH.

an appropriate blocking group, to insure reaction between the acid salt and the 3-amino substituent.

The compounds wherein Z is a coupling position may (3) OH be represented by the following formula:

o (l)CH3 o xt u n l -N- S N=N '-C-NHn-UzHl t l l l l HO wherein R, R1, n, Y and D have the meanings heretofore v0 noted; X1 is hydroxy or an amino substituent as heretofore noted in connection with the description of the X moiety; and Z1 is hydrogen or any of the substituents such as heretofore mentioned which are replaceable by oxidized aromatic amino color developer to effect ring closure in a HsiCit manner similar to that described m certain of the aforeo mentioned patents and to be described with more particu- I`I I}C` N=N larity hereinafter. l

As examples o f useful compounds within the scope of 00H3 H HO Formula B, mention may be made of the following:

Cl H O O H (5) H'vsCiz-N-C -t-t-O-@-M -H-m N l HO N,

O H NH C-CHJ O H Hl C O -N=N Cubin@ N=N HOiS SOxH l O C Hs -N-S 0H H O HasCir-IlI-ill CH) O rit-i-@orrr-Cm-o HrtCtz-IlI-ill H O ,at

The compounds of Formula B, e.g., compounds such as those illustrated above by Formula l-8, may be employed in photosensitive elements in various systems to prepare either positive or negative color transfer images.

One such system utilizes photosensitive elements such as that illustrated in FIGURE l to prepare negative color transfer images. As shown therein, a photosensitive element is providedv comprising a light-sensitive silvex halide emulsion layer 10 and a layer 12 of the color-providing material of Formula B, carried on a suitable transparent or opaque support 14. In the preparation of negative images according to this embodiment, emulsion layer 10 comprises any of the conventional silver halide emulsions, e.g., silver chloride, silver bromide, silver bromoiodide, silver chlorobromide or silver chlorobromoiodide. The emulsion layer may also contain the various additives heretofore employed in such layers, e.g., optical sensitizers, antifoggan-ts, hardeners, plasticizers, coating aids, speed-increasing materials, ultraviolet absorbers, etc. The dispersing agent or substrate for the silver halide may be gelatin or some other colloidal material.

As examples of typical materials which may be employed for the support 14, mention may be made of films of cellulose nitrate, cellulose acetate, polyvinyl acetal, polystyrene, polyethylene terephthalate, polyethylene, polypropylene, etc., paper, glass and others.

When this photosensitive element is exposed and then developed in the presence of a primary aromatic amine color developer by spreading an aqueous alkaline processing composition 116 between the thus exposed element and an image-receiving layer or dyeable stratum 18 shown to be carried by a suitable support 20 as a second element, a negative transfer image is formed. Image formation is obtained by coupling of oxidized color developer formed in terms of areas of exposure with the color-providing material, followed by ring-closure and splitting olf of mobile and ditfusible color-providing material to provide an imagewise distribution of this material in terms of areas of exposure. At least a portion of this imagewise distribution is transferred -by imbibition, to the image-receiving layer to provide a negative color transfer image there- While it is not intended to be restricted to any particular theory, the reaction mechanism upon which image formation is believed to be predicated may be illustrated by the following reaction between a color-providing ma- NH: O

terial such as that of Formula l and N,Ndiethylpphen ylenediamine as the color developer:

Thus, image formation is predicated upon ring-closure of the non-ditusible compound with elimination and subsequent transfer of a compound comprising essentially the color-providing moiety, which latter compound may be represented by the formula: H-Y--D.

From the foregoing reaction, it will be apparent that the character of the color transfer image is predicated upon the spectral absorption characteristics of the colorproviding moiety, D. For purposes of this invention, the color-providing moiety may be of any desired color, particularly Where monochromatic images are contemplated. However, by appropriate selection of color-providing materials, eig., complete dyes exhibiting the requisite spectral absorption characteristics, the present invention is adaptable to the known systems for preparing accurate multicolor reproductions of the original subject matter, e.g., those utilizing photosensitive elements comprising a red-sensitive silver halide emulsion stratum, a greensensitive silver halide emulsion stratum and a blue-sensitive silver halide emulsion stratum, the emulsions having associated therewith, respectively, a cyan, a magenta and a yellow color-providing material. The color-providing moiety may be initially colorless or of a color other than that desired but which upn processing or other treatment, c g., hydrolysis, undergoes a color shift to the desired color. Such moieties are known in the art and per se comprise no part of this invention.

-It will also be apparent that the remainder of the molecule, i.e that portion of the compounds of Formula B other than the dye moiety, does not form any part of the color transfer image, it being retained in the photosensitive element because of the anchoring substituent. Accordingly, other than the prerequisite abovenoted that this portion of the molecule be non-diffusible and permit the coupling reaction with oxidized color coupler which results in ring-closure and removal of the color-providing moiety, the particular substituents contained therein are likewise immaterial for purposes of this invention.

It will be noted that certain of the aforementioned U.S. patents, e.g., 2,543,338 and 3,245,795, relate to systems involving a compound which may react with oxidized color developer to elfect ring-closure and elimination of a substituent bonded to a nitrogen atom in the three position. In the patented processes, the eliminated substituent forms no part of the image formed. The present invention, which is analogous in certain respects to the patented processes, may be said to be an entirely different and novel system wherein the substituent eliminated is transferred to another stratum to form the color image thereon.

The primary amino color developing agents employed may be any of those heretofore known in the art, e.g., color developers such as disclosed in any of the aforementioned patents. While color developers of the p-aminophenol series may be employed, the preferred developers are of the p-phenylenediamine series. The color developing agents can be either incorporated in the aqueous alkaline composition or they may be incorporated in the light-sensitive element itself.

As illustrative examples of the preferred class of aromatic primary amino color developing agents, mention may be made of:

4-amino-N-ethyl-3 -methoxy-(-sulfoethyDaniline,

N-ethyl--methanesulfonamido-ethyl-3-methyl- 4aminoaniline,

4-amino-N-ethyl-3-methyl-N- -sulfoethyl) aniline,

4amino-N-ethyl-3-methoxy-N-(-sulfoethy.l)aniline,

4-amino-N,Ndiethyl3-hydroxymethyl aniline,

4-amino-N-m ethyl-N- (-carboxyethyl) aniline,

4-amino-N,Nbis(-hydroxyethyl) aniline,

4-amino-N,Nbis -hydroxyethyl) -3 -methyl aniline,

4-amino-N-ethyl-N- (2,3 -dihydroxypropyl) -3 -methyl aniline sulfate salt,

containing a coupling position ortho to the primary amino substituent, so that the reaction product obtained from coupling of the oxidized developer with the color-providing material may auto-react intramolecularly to effect ring-closure and elimination of the mobile color-providing moiety.

When the color developing agent is present initially in the photosensitive element, it may be advantageous to use forms that have substantial stability in emulsions, such as Schiff base derivatives of primary amino developing agents. Such Schiff bases are prepared by reacting primary amino developing agents with sulfonated, hydroxylated or carboxylated aromatic aldehydes of the benzene or naphthalene series. A typical Schiff base color developing agent can be prepared by reacting 2-amino-5- diethylamino-toluene and o-sulfobenzaldehyde. Other Schilf base developers that are useful as such, as salts or as sulfur dioxide complexes include:

Such incorporated developing agents can be activated by immersing the photographic element in an aqueous alkaline solution on the surface of the element. Such inand corporated developing agents can be positioned in any layer of the present photographic elements from which the developing agents can be readily made available for development on activation with aqueous alkaline solutions. Generally, such incorporated color developing agents are incorporated in layers contiguous to the lightsensitive silver halide emulsion layers, although the color developing agent can be utilized in the silver halide emulsion layers.

In addition to the alkaline material, the processing composition may include additional reagents performing specific desired functions, e.g., viscous film-forming reagents such as hydroxyethyl cellulose, sodium carboxymethyl cellulose, etc., antifoggants, etc., it being understood that any of these ingredients may be present initi-ally in the 4film unit, in which case the processing composition containing the developer, alkaline material, etc. is formed by contacting the iilm unit with the aqueous medium therefor. In any event, the processing composition may, if desired, be confined in a frangible container or pod such as described, for example, in U.S. Patents Nos. 2,543,181 and 2,634,886, issued to Edwin H. Land.

While for purposes of illustrating this aspect of the invention, the color-providing material has been shown in FIGURE 1 as being present in a separate layer in the photosensitive element, the color-providing material may, if desired, be present in the layer containing the silver halide emulsion.

The following example shows by way of illustration and not by way of limitation the preparation of lthe compounds of Formula B.

EXAMPLE 1 500 g. of methyl p-amino-benzoate were added to 1,250 ml. of acetic anhydride with stirring, While maintaining the temperature of the mixture between 50 and 60 C. After addition was complete, the mixture was chilled. A white solid, which precipitated, was removed by suction lfiltration and air-dried under a hood. 5019.7 g. (79.8%) of 4-carbomethoxyacetanilide (M.P. 131-133 C.) were obtained. A mixture of 315.8 g. (1.63 moles) of this compound, 1,250 ml. of glacial acetic acid, and 600 ml. or acetic anhydride was stirred with external cooling until the temperature dropped to about 2 C. Nitrous fumes, prepared from 500 g. of sodium nitrite and 500 ml. of nitric acid (sp. gv. 1.42), were bubbled into the mixture for two hours, after 'which time the resulting dark green, clear solution was stirred into 5 l. of crushed ice. A light yellow precipitate was removed by suction filtration, washed thoroughly with lwater, pressed between dilter papers, and then dried in vacuo over anhydrous calcium chloride to yield 250.2 g. (618.8%) of 4-carbomethoxy-N-nitrosoacetanilide. `Over a period of two hours with vigorous stirring, 250.2 g. (1.13 moles) of this compound were added to 560 g. (2.98 moles) of molten 4-chloro-3-nitroanisole. The temperature of the mixture was kept between 50" and 60 C. during the addition. Stirring was continued for an additional 15 minutes, after which the excess anisole was removed by steam distillation. The resulting ydark brown residue was triturated with 1,500 ml. of ether. The ether-insoluble solid was removed by suction ltration and washed with small portions of ether. One recrystallization of this solid from ethanol yielded 18.5 g. (5.8%) of (2-methoxy-4-nitro-5-chloro-4- carbomethoxy)diphenyl, 18\9-191 C., having the following structural formula:

1 l To 14.2 g. (0.466 m.) of this compound in 400 ml. of methylene chloride, 75 ml. of boron tribrornide were carefully added. The resulting dark red solution was allowed to stand overnight at room temperature and then treated dropwise with anhydrous methanol until further addition of methanol no longer produced an exothermic reaction. After treatment with water, the mixture was extracted with ether, the ether layer extracted with cold 1% sodium hydroxide solution, the alkaline solution was iiltered and acidifled with hydrochloric acid. The resulting creamcolored solid was ltered, washed with water and dried. 12 g. of (2-hydroxy-4-nitro-5-chloro-4carbomethoxy) diphenyl were obtained. [This product was found to contain free acid, M.P. soft 238 C., m. Z50-253 C. dec. A small amount of ester was puried by extraction with sodium bicarbonate solution followed by recrystallization from methanol, M.P. 23S-237 C.] A mixture of 12 g. of the diphenyl prepared above, 25() ml. of ethanol and 75 ml. of 10% sodium hydroxide solution was heated on the steam bath for minutes. The resulting red solution was filtered, acidied with hydrochloric acid, iltered, washed and dried to yield 11.4 g. of (2-hydroxy-4-nitro- 5chloro-4carboxy)diphenyl, M.P. 251-252 C. 4 g. of this compound, ml. of acetic anhydride and 1 ml. of pyridine were heated on a steam bath for live hours. The resulting solution was evaporated to dryness and the residue recrystallized from ethyl acetate-hexane to yield 4.5 g. of (2-acetoxy-4-nitro-5-chloro-4carboxy) diphenyl, M.P. 211.5-213.5 C. A mixture of 4.5 g. of this compound and thionyl chloride was reuxed for one hour. The excess thionyl chloride was then allowed to distill at atmospheric pressure over 30 minutes and the residue was evaporated at 40 C. at water-pump pressure. The yellow solid acid chloride was directly dissolved in 250 ml. of

dry benzene and added dropwise with stirring to a solution of 6 g. of dodecylamine hydrochloride in 25 ml. of triethylamine at ice bath temperature. The mixture was allowed to stir overnight at room temperature, after which it was poured into dilute hydrochloric acid solution and extracted with methylene chloride. The organic layer was washed three times with dilute hydrochloric acid solution, then with water until the aqueous layer was neutral to pH paper. The methylene chloride solution was dried over anhydrous magnesium sulfate, ltered and evaporated to dryness to yield a brown oil. The brown oil was chromatographed on Florisil using ether-hexane and the product was present in the tirst yellow band which eluted. Partial evaporation of the ether solvent and addition of hexane produced waxy yellow akes. A recrystallization from ether-hexane and another from methylene chloride-carbon tetrachloride produced 2.8 g. (in two crops) of 2-hydroxy-4-nitro-5-chloro4carbo-n-dodecylamide diphenyl, M.P. 14S-148 C., having the following structural formula:

A mixture of 2.76 g. of this compound, 150 ml. of anhydrous ethanol, l ml. of concentrated hydrochloric acid and about 2 g. of 5% palladium on carbon was hydrogenated a troom temperature at an initial pressure of 40 pounds per square inch. Reduction required about one hour. The mixture was then -ltered, the residue washed with anhydrous ethanol and the iiltrate evaporated to a small volume. Anhydrous ether was added to the colorless solution and upon cooling, 2.7 g. of (2-hydroxy-4- amino hydrochloride-S-chloro-4'-carbondodecylamide) diphenyl was obtained, M.P. 207-215 C. dec. A mixture of l g. of this compound and 1.4 g. of 4-(2-naphthol-lazo) benzene sulfonyl chloride in ml. of pyridine was stirred at room temperature for three hours at which time complete solution was obtained. The solution was allowed to stand at room temperature overnight, poured into ice-water and iiltered.-After work-up of the mother liquor and recrystallization from glacial acetic acid, 1.2 g. of the compound of Formula 1 was obtained, M.P. 292-232 C. maX =482; e=23,400 in methyl Cellosolve.

The following example shows by way of illustration and not by way of limitation the preparation of negative color images in accordance with the previously described aspect of this invention.

EXAMPLE 2 A rst coating solution was prepared containing a mixture of 0.14 g. of the compound of Formula 1, 0.2 g. of cellulose acetate hydrogen phthalate, 5.0 cc. of acetone and 7.0 cc. of methyl Cellosolve. This solution was coated at room temperature at a rate of l0 feet per minute on a cellulose triacetate base which had been coated with 200 mg. per square foot of gelatin. After this coating had dried, a second coating solution was applied at the same rate containing 8.0 cc. of a standard light-sensitive silver iodobromide emulsion, 28.0 cc. of water, and 2.0 cc. of 1% aqueous Triton X- (trademark of Rohm & Haas Co. for a monionic isooctyl phenyl polyethoxy ethanol dispersing agent). This coating was made in the dark with the temperature of the coating solution kept at 40 C. The resulting photosensitive element (as illustrated in FIGURE l) was exposed for /OO of a second and the thus exposed element was then developed by spreading between this element and a superposed image-receiving element at a gap of .0036", a processing composition comprising the following proportions of ingredients:

Water cc-- 100.0 Hydroxyethyl cellulose g 3.9 Potassium hydroxide g 4.9

ADAT (2-amino-5-N,Ndiethylaminotoluene) g 2.0

The image-receiving element was prepared in accordance with the disclosure of the copending application of Edwin H. Land, Ser. No. 234,864, led Nov. l, 1962, now U.S. Patent No. 3,366,819 and comprised a layer of a 2:1 mixture by weight of polyvinyl alcohol and poly- 4-vinyl pyridine, a layer of polyvinyl alcohol, and a layer of a half-butyl ester of poly-(ethylene/maleic anhydride) coated on a baryta paper support. After an imbibition period of about three minutes, the image-receiving element was separated to reveal thereon a negative yelloworange image.

In the foregoing embodiment of the invention, negative color transfer images are obtained. Following transfer image formation, it will be appreciated that there remains in the photosensitive element an imagewise distribution of dye in terms of unexposed areas in addition to developed silver in exposed areas. Residual amounts of dye may also be present in areas correspondng to exposed areas. A positive image may be obtained in this element by removal of the silver in conventional manner, eg., by bleaching and subsequent fixation. lf desired, any residual color-providing material remaining in exposed areas may also be removed by conventional techniques to provide clean highlight areas in the resulting positive image.

Positive color transfer images may also be obtained by various systems in accordance with this invention.

One such system utilized a photosensitive element such as illustrated in FIG. 2. As shown therein, the photosensitive element includes a support 14 having thereon, in order, a layer 22 of the color-providing material of Formula B and a prefogged silver halide emulsion; and, a layer 24 containing a non-diifusable color coupler and an unexposed light-sensitive silver halide emulsion. The non-difusible coupler may, for example, be any of the conventional couplers containing an anchoring moiety rendering it fast to diffusion, as described in certain of the aformentioned patents, e.g., U.S. Patent No. 2,543,338, or it may comprise a non-diiiusible polymer containing one lli or more coupling moieties. It will be appreciated that, instead of being contained in the same layer, the colorproviding material and prefogged emulsion and/or the unexposed emulsion and coupler may respectively be contained in separate contiguous layers.

The photosensitive element of FIG. 2 is exposed and developed in the presence of an aromatic primary amino color developer in the manner illustrated in FIGURE 1, that is, by spreading an aqueous alkaline processing composition between the thus exposed element and a superposed image-receiving layer. The color developer develops the exposed and developable silver halide in layer 24 and oxidized developer in terms of exposed areas couples in known manner with the non-diffusible coupler and hence is immobilized. Unexhausted or unreacted color developer (in terms of unexposed areas) diffuses through layer 24 to the prefogged emulsion where it is oxidized and the oxidized developer then reacts with the color-providing material in layer 22, in the manner heretofore described, to release a diffusable color-providing moiety. This diffusable substance formed in terms of unexposed areas of layer 24 is then free to transfer, by imbibition, to the image-receiving layer to form a positive color transfer image thereon.

The following example shows by way of illustration and not by way of limitation this aspect of the invention.

EXAMPLE 3 A first mixture was prepared containing 6.0 cc. of a silver iodobromide emulsion fogged by exposure to light, 15.0 cc. of water, and 2.0 cc. of 1% Triton X-l00. A second mixture was prepared by first mixing 0.7 g. of the compound of Formula 1, 0.5 cc. of triethylphosphate, and 0.5 cc. of diethyldecamide. This mixture was heated to 90 C. with constant stirring, after which 7.0 cc. of gelatin and 1.0 cc. of 5% Alkanol B (trademark of E. I. du Pont de Nemours & Co. for a light creamcolored wetting and dispersing agent, alkylnaphthalene sodium sulfonate) were added. The resulting mixture was mixed and heated for 60 seconds while stirring vigorously, after which it was chilled and washed with cold water for six hours. It was then melted by heating to C. and 12 cc. of this melted mixture was added to the first mixture prepared above. The resulting combined mixture was then coated on a cellulose triacetate base at 40 C. at 10 feet per minute to provide a single layer containing a fogged silver halide emulsion and the compound of Formula l. A second coating Was prepared by mixing 4 cc. of a silver iodobromide emulsion, 28 cc. of water, 2 cc. of Triton X-100 and 2 g. of 2-octadecylamido-lnaphthol-4-sulfonic acid, a non-diffusible coupler of the formula:

o E t It @/-o-N-(omm-Cm SOaH This mixture was filtered through a silk screen, diluted with 4 cc. of water and then coated over the fogged emulsion compound layer prepared above at 40 C. and at l0 feet per minute, thereby providing a photosensitive element such as shown in FIG. 2. The resulting photosensitive element was exposed for IOO of a second and then developed by spreading between the exposed element and a superposed image-receiving element similar to that described in Example 1, at a gap of .0056", a processing composition containing the following proportion of ingredients:

Water cc 100.0 Hydroxy ethyl cellulose g 3.9 Potassium hydroxide g 4.9 ADAT g-- 0.5

After about 30 minutes, the respective elements were separated to reveal a positive yellow-orange transfer image.

In the following example, the procedure of the foregoing example was modified to provide an additional layer containing the non-diffusible coupler.

EXAMPLE 4 A first mixture was prepared containing 6.0 cc. of fogged silver halide emulsion, 15.0 cc. of water, and 2.0 cc. of 1% Triton X-100. A second mixture was prepared by first admixing at C., 0.87 g. of the compound of Formula 1, 0.6 cc. of triethylphosphate and 0.6 cc. of diethyldecamide. After complete solution was effected, 8.7 cc. of 10% gelatin and 1.0 cc. of 5% Alkanol B was added at 40 C. The resulting mixture then chilled, and subsequently melted by heating to 40 C. l2 cc. of the second mixture were then added to the first mixture and the combined mixture was coated on a transparent cellulose triacetate base at 10 feet per minute. After this layer dried, a second layer was coated thereover at 40 C. and at 10 feet per minute comprising 4.0 cc. of 10% gelatin, 29.0 cc. of water, 3.0 cc. of 1% Triton X- and .08 g. of 2-octadecylamido-l-naphthol-4-sulfonic acid. Finally, at 40 C. and at 10 feet per minute a third coating layer was applied comprising 4 cc. of silver iodobromide emulsion, 28 cc. of water, 2 cc. of 1% Triton X-l00 and .2 g. of the aforementioned 1- naphthol coupler. Exposure of photosensitive elements prepared as above and development in the manner described in Example 3, employing imbibition times of 10, 14, 15 and 22 minutes gave positive transfer images.

Another system for preparing positive images in accordance with this invention utilizes a structure similar to that described above, except that a layer of silver precipitating or physical development nuclei is employed in lieu of the prefogged emulsion. Such nuclei, which are well known in the art, include noble metals such as silver or gold; colloidal metal sulfides, selenides, and tellurides; metal proteinates such as silver proteinates; sodium sulfide; colloidal sulfur; and such organic sulfur compounds as thiourea, exanthates, etc. The silver-precipitating nuclei and the non-diffusible compound containing the colorproviding moiety may be in the same or contiguous layers behind the light-sensitive silver halide emulsion, as previously described.

When a structure of the foregoing description is exposed and then developed with an aqueous alkaline processing composition including a silver halide solvent, e.g., sodium or potassium thiosulfate, and an aromatic primary amino color developer (which ingredients may be contained initially in the film structure, as previously described), exposed silver halide is reduced to silver by the color developer and oxidized color developer formed as a function of development couples with the non-diffusible coupler and is hence immobilized. In unexposed areas, an imagewise distribution of soluble silver complex and unreacted developer is formed. This imagewise distribution migrates to the layer containing the silver precipitating nuclei where in the presence of the precipitating nuclei, the silver complex is reduced and the oxidized developer formed as a function thereof reacts with the non-diifusible compound to effect elimination of the color-providing moiety in an imagewise pattern corresponding to unexposed areas of the emulsion. This imagewise pattern is then free to transfer, by imbibition, to the image-receiving layer to form a positive dye transfer thereon.

Monochromatic positive transfer images may also be prepared in a modification of the above procedure Wherein the processing composition contains a viscous dispersion of the precipitating nuclei, the non-diffusible compound, the color developer and the silver halide solvent and the photosensitive element contains essentially only the light-sensitive silver halide emulsion and the nondiffusible coupler. Upon development, color developer oxidized as a function of development of exposed areas of the emulsion is immobilized by coupling with the nonditfusible coupler in the manner described, while a soluble silver complex formed in terms of unexposed and unreacted areas migrates into the viscous processing reagent where, in the presence or the silver precipitating nuclei, it is reduced by the color developer which, in turn, is oxidized to react with the non-diifusible compound, thereby eliminating the color-providing moiety for transfer. Upon separation of the image-receiving element, a positive dye transfer image may be obtained, the reduced silver complex and the remaining reacted and unreacted ingredients in the processing composition being retained therein to provide clean separation.

In addition to the systems previously described, positive transfer images may be obtained by the various systems described in the aforementioned U.S. Patents Nos. 3,227,550; 3,227,551; 3,227,552; 3,227,554; and 3,243,- 294.

With reference again to the photosensitive element of FIGURE 1, one such system comprises the steps of first developing with a black-and-White developer, e.g., a hydroquinone-type developer, thereafter rendering the unexposed and undevelopable areas developable by flash exposure or chemical fogging in the usual manner, and then developing these latter areas with the color developer to form a positive color transfer image. It will be noted that this system for positive color image formation requires two exposures and two separate developing steps.

Another system utilizes direct positive silver halide emulsion layers to obtain a positive color transfer image with a single development in the presence of a color developer. Unlike the more conventional silver halide emulsions containing silver halide grains that have substantial surface sensitivity and form latent images when exposed to light on the surface thereof, one useful class of direct positive emulsions comprises internal silver halide emulsions wherein the silver halide forms latent images predominantly inside the silver halide grains when exposed to light. Internal image emulsions of this nature are described, for example, in U.S. Patent No. 2,592,250. Internal image silver halide emulsions can be defined in terms of the increased maximum density obtained when developed with internal-type developers over that obtained when developed with surface-type developers. Suitable internal image emulsions are those which, when measured according to normal photographic techniques by coating a test portion of the silver halide emulsion on a transparent support, exposing to a light intensity scale having a fixed time between 0.01 and 1 second, and developing for 3 minutes at 20 C. in a typical internal-type developer have a maximum density at least five times the maximum density obtained when an equally exposed silver halide emulsion is developed for 4 minutes at 20 C. in a typical surface-type developer.

Another class of useful direct positive emulsions are solarizing silver halide emulsions, that is, well-known silver halide emulsions which have been effectively fogged either chemically or by radiation to a point which corresponds approximately to the maximum density of the reversal curve as shown by the aforementioned Mees test, The Theory of the Photographic Process, chapter 7, pp. 243-297.

Direct positive emulsions of the foregoing description are also disclosed, for example, In U.S. Patents Nos. 3,227,550 and 3,227,552.

As in the systems disclosed in these patents, the colorproviding materials of this invention may be present in a separate layer contiguous with the direct positive emulsion layer or it may be incorporated therein. Multilayer elements containing at least three emulsion layers sensitive to different regions of the visible spectrum and having associated therewith appropriate color-providing materials may be employed to provide multicolor images. In accordance with the present invention, positive color images may be obtained with photosensitive elements containing one or more direct positive emulsions such as described above, by exposing and developing in the presence of a color developer in the manner described with particularity in the aforementioned U.S. Patents Nos. 3,227,550 and 3,227,552.

In another system for preparing positive color transfer images, use may be made of photosensitive elements containing a conventional silver halide emulsion and further containing a Schiff base of an aromatic primary amino color developer (as previously described). In this system, black-and-white development is effected under acidic conditions, e.g., at a pH of 0.9, with an aqueous solution of a reducing agent such as titanous chloride (c g., a 1% solution) which is a mild reducing agent under such acidic conditions. After the negative silver image is developed, the processing solution is made alkaline. Under alkaline conditions the titanous chloride is a stronger reducing agent and serves as a chemical fogging agent for remaining unexposed and undeveloped silver halide to form a positive image area. In the alkaline medium the Schliff base of the color developer splits and color development takes place freeing for transfer to the image-receiving layer the diifusible dye moiety in terms of the chemically fogged (initially unexposed) areas.

Still another system for preparing positive color transfer .images by the present invention utilizes a novel modification of the teachings of U.S. Patent No. 3,227,551. In this embodiment, use is made of a photo-sensitive element containing: (a) a light-sensitive silver halide emulsion; (b) a color coupler such as described in the patent which is capable of forming a ditfusible mercaptan development inhibitor with a processing composition containing an aromatic primary amino color developing agent; (c) one of the spontaneously developable metal salt emulsion layers such as described in the patent, eg., a fogged silver halide emulsion; and (d) a color-providing compound such as dened in Formula B. When such an element is exposed and developed in the presence of the color developer, the coupler (b) reacts with the colordevelopment oxidation product to form the designated development inhibitor which diffuses to the spontaneously developable emulsion layer to inhibit development thereof in terms of exposed areas of the silver halide emulsion (a). In regions not inhibited (unexposed areas), development is accomplished by the color developer and the oxidized product then couples with the compound (d) with subsequent ring-closure and elimination of the diffusible color-providing moiety which is then free to transfer, by imbibition, to the image-receiving layer to form a positive dye transfer image thereon.

Yet another system for preparing positive color transfer image is based upon a novel variation in procedure over the invention disclosed in U.S. Patent No. 3,243,294. In this embodiment, the photosensitive element includes, in addition to the elements described previously in connection with the description of FIGURE l, a diusable black-and-white developer and silver precipitating nuclei. When exposed and developed in the presence of the color developer, the black-and-white developer first develops the emulsion to form a negative silver image Without at least any appreciable formation of diffusible color-providing material. Thereafter, unexposed areas are developed by the color developer to provide, in terms of unexposed areas, an imagewise distribution of oxidized color developer which in turn, inthe manner previously described, frees for transfer the color-providing moiety to form the positive color image on a superposed image-receiving layer.

As inthe first-named embodiment for forming negative images, it will be appreciated that a color image may be provided in the photosensitive element by conventional bleaching and xing techniques. In this instance, however, the image so formed will be a negative (reversed) image. Such a procedure may be particularly useful wherein exposure is made through a negative to provide a positive reproduction of the original subject matter (a negative of the negative) which may, for example, be viewable as a positive transparency.

In the foregoing description of photographic systems within the scope of this invention, reference has been made to compounds within Forumla A wherein Z is a coupling position, i.e., compounds of Formula B such as the illustrative compounds 1 8.

As was mentioned previously in the description of the compounds of Formula A, Z may also be an aromatic amino substituent, particularly one which is the radical of an aromatic primary amino color developer of the p-phenylenediamine and p-aminophenol series, or a naphthylamino radical, including p-aminonaphthylamino and phydroxynaphthylamino analogues thereof, provided that all of these aromatic substituents have a free position ortho to the -NH- substituent to permit ring-closure and elimination of the color-providing moiety in the designated manner.

This later class of compounds may be represented by the following formula:

1 (c) tn-1) L /l-N-Y-n I mr 4 *n R (n1-1F31 wherein X2 is hydrogen, hydroxy, an amino group 0f the formula:

such as may be contained by said X moiety, as previously described, or the substituent R4 provided that one of said X and X2 moieties must be hydroxy or amino; A1 represents the atoms necessary to complete a benzene or naphthalene ring, which ring may be further substituted; R4 has the same meaning as R; n1, like n, is a positive integer from 1 to 2, provided that when Rl or R3 alone or together comprise one of those heretofore named substituents rendering the compound non-diffusible, either or yboth n and n1 may be 1, but when R1 and R3 alone or together do not provide such an anchoring moiety, at least one of n and n1 must be 2.

The compounds of Formula C may be prepared by coupling a dye of the formula:

Cl-Y-D with a compound of the formula:

4 l. R (n1-1) A1); x2

Where X and/or X2 is hydroxy, it may be necessary or advisable for the hydroxy moiety to be present as a protected derivative, eg., as an alkoxy substituent, during coupling, in which event the desired hydroxy analogue may subsequently be obtained by hydrolysis.

The preferred compounds of Formula C may be represented by the formula:

wherein the anchoring moiety R or R4 comprises a long chain amide, e.g., of at least 13 carbon atoms bonded directly to a nuclear carbon atom of the designated benzene nucleus or linked thereto through a phenylene or alkylene linking substituent and nuclear substituted derivatives thereof, e.g., where any of the nuclear carbon atoms of the respective benzene moieties not containing one of the specifically designated substituents may contain a carboxy, alkoxy, alkyl, chloro, hydroxy or an amide substituent, etc.

The preferred subclass of Formula F may be prepared by coupling in the manner described with regard to the broader class of Formula C, followed by dealkylation of the protected hydroxy group. Where the starting materials are not readily available, they may be prepared by the steps set forth in the following sequence of reaction steps:

Qns

(10) lil HzaCn-N- (Il) Cgi/02H5 N I? i HrsCxn-N-C- N=N N/ Rui-1) Roz-1) -NHI -NH-sOz-D 15TH Cl-sOz-D IIH Rmlm@ :mm1-ll@ CH3 CH3 (v) Rx-i) -NH-sOa-D NIL-sol-D BBR NE NH H10 l RM1-xr@ Ru-nn@ OCE:

Formula F They may also be prepared by coupling of any of the protected derivatives of the know p-aminophenol developers with an ortho-iluoro-nitrobenzene, followed by reduction of the nitro group, coupling of the dye-containing moiety D-SOz-Cl, and hydrolysis in the aforementioned manner, according to the procedure described and claimed in the copending application of Harris L. Curtis, Ser. No. 655,304 tiled concurrently.

As examples of useful compounds contemplated by Formula C mention may be made of the following:

5 NH HzN 0 H CI) Il NH .Lx-@ om-onr-o N\ E 4 C nHu CH3 I CH3 n movi-@ l Compounds 24 and 25 contain a color-shifted yellow dye moiety; and Compounds 28, 29 and 3l conta-in a color-shifted magenta dye moiety. These compounds are initially substantially colorless but upon hydrolysis, e.g., in an alkaline photographic processing iluid, provide yellow and magenta dyes, respectively. Compounds containing such color-shifted dye moieties and the advantages in photography are described 'in U.S. Patents Nos. 3,230,- 085 and 3,307,947 respectively.

It will be observed that the compounds of Formula C, e.g., illustrative Compounds 9-31 contain both a dye moiety and a developing moiety, e.g., an aromatic amino moiety containing a p-'hydroxy or p-amino substituent. When oxidized imagewise, as for example, by reducing silver halide to image silver during processing, the oxidation product thereof auto-reacts intramolecularly in the manner previously described to effect ring-closure and elimination of the dye moiety from the remainder -of the molecule.

As these compounds are relatively non-diffusible in the photosensitive element, they should fbe employed in systems wherein the oxidizing material, e.g., silver halide reducible to image silver, is brought to the compound instead of vice versa.

For example, the non-diffusible compound may be present in the photosensitive element, e.g., in a layer behind the light-sensitive silver halide emulsion, along with silver precipitating or physical development nuclei (such as previously described).

A photosensitive element of this description during processing thereof is shown in FIG. 3 as comprising a support 14 having thereon a layer 26 of color-providing material of Formula C, e.g., a non-dilusible compound such as one of the illustrative Compounds 9-31, and a silver precipitating agent; and a silver halide emulsion layer 10.

When `such a photosensitive element is exposed and then developed with an aqueous alkaline processing cornposition including a silver halide developing `agent (to be described with more particularity hereinafter) and a silver halide solvent, e.g., sodium or potassium thiosulfate, etc., in known manner exposed silver halide 'is reduced to silver while a soluble silver complex is formed in terms of unexposed and undeveloped areas `of the emulsion. This imagewise distribution of soluble silver complex 'is at least in part transferred into contact with the nondilusible color-providing compound where, in the presence of the precipitating nuclei, it is reduced and the developer in turn oxidized in an imagewise pattern corresponding to unexposed areas of the emulsion. The oxidation product then ring-closes with elimination of diffusible dye which is then free to transfer, by imbibition, to an image-receiving layer to form a positive ima-ge thereon.

It has been discovered that in the system just described two competing reactions are possible: (l) the described reaction between the soluble silver complex and the colorproviding material in layer 26 in the presence of silver precipitating nuclei to release an imagewise distribution of dilusible dye in terms of unexposed areas of emulsion layer 10; and (2) a redox reaction between oxidized silver halide developing agent, that is, developing agent in processing composition 16 which is oxidized as a function of development of exposed silver halide, and the color-providing material, whereby the latter is oxidized and then ring-closes with elimination of diffusible color-providing material in terms of exposed areas of the silver halide emulsion. Without appropriate controls, it is possible for both reactions to occur at the same time so that a uniform transfer of dye occurs in both exposed and unexposed areas, thereby precluding formation of a usable color transfer image. Stated another way, without proper controls, it is possible for transfer in the so-called Dmax, and Dmm areas to be of substantially equal density so that no image is obtained or, if a recognizable image is obtained, the image is of undesirable quality.

To obviate this diculty so as to obtain a positive color image in the previously described manner, it will, therefore, be apparent that this redox reaction which releases diffusible color-providing material in exposed areas, must be avoided, at least in terms of exposed areas.

One such procedure is to employ as the silver halide developing agent for development of exposed silver halide in layer 10 a relatively immobile developing agent which, at least in its oxidized form, cannot migrate to layer 26 in any appreciable amount during processing. In simple words, if the oxidized developing agent cannot migrate to contact the color-providing material in layer 26, the fundesired redox reaction cannot occur. On the other hand, the developer rnust be of sufficient mobility in the developing composition, at least in its unoxidized form, to develop emulsion layer 10. Developing agents meeting these qualications are heretofore |known in the lart and per se comprise no part of this invention. As examples of such useful developers, mention may be made of hydroquinonyl-type developers containing bulky substituents, e.g., the triptycene diol developing agents described and claimed in U.S. fPatent No. 3,064,075. iIt is also contemplated that one may employ developing agents which are irreversibly oxidized as a function of development, i.e the oxidized form of which is not reducible, e.g., the hydroxylamine developers.

Another system for obviating the redox reaction is to include in the photosensitive element a material which will intercept any oxidized developer and render it innocuous before it can migrate to the color-providing material in layer 26. Such materials may be delined as being scavengers for oxidized developer.

As examples of useful scavengers, mention may be made of the following:

Another control for obviating the redox reaction is the use of an immobile developing agent in the emulsion layer in lieu of having the developer present initially in the developing composition. For example, where a developer is found to be too immobile to be employed in the developing composition in the first-named system for controlling the redox reaction, it may be positioned initially in the emulsion layer, e.g., layer 10.

The following examples show by way of illustration and not by way of limitation the preparation of compounds of Formula C and their use in the disclosed photographic systems to obtain positive color transfer images.

EXAMPLE 5 11.0 g. (0.05 mole) of -nitrodehydrocoumarin was dissolved in 100.0 cc. of methyl Cellosolve. 12.0 g. (0.064 mole) of n-dodecylamine was then added. [The reaction was exothermic and a yellow solid separated out.] The mixture was heated until a clear solution was obtained and then cooled to give 14.0 g. of light yellow crystals, M.P. 168-170, an amide of the formula:

A mixture of 16.5 g. (0.0437 mole) of this amide, prepared in the manner described above, 7.0 g. (0.056 mole) of dmethylsulfate, 9.2 g. (0.066 mole) of potassium carbonate and 250 ml. of xylene was reuxed overnight. The xylene was then removed by steam distillation and an oily product crystallized on standing. Recrystallization of this product from hexane-chloroform yielded 13.3 g. of light tan needles, M.P. 106-108 C. of the formula:

13.3 g. of this latter amide was hydrogenated in ethanol in the presence of a Raney-nickel catalyst. The reaction mixture was filtered and the ltrate evaporated. The resulting solid was recrystallized from hexane-ether to obtain 9 g. of a pure white amine, M.P. 80-82 C. of the formula:

52 g. (0.145 mole) of the amine prepared in the above manner, 21.0 g. (0.145 mole) of Z-ftuoronitrobenzene, 7.85 g. (0.195 mole) of magnesium oxide and 100.0 ml. of water were 'heated in a sealed bomb at 180 C. for 18 hours. The contents of the bomb were then tiltered and the solid obtained by ltering was stirred in boiling ethyl acetate and iiltered. Cooling of the iltrate yielded 40 g. of light yellow solid, M.P. 12S-126 C. of the formula:

29 10.0 g. of the last-named product was hydrogenated with Pd/BaSO4 in ethyl acetate to reduce the nitro group to the corresponding amine. The reaction mixture was filtered and the filtrate was then cooled in Dry Ice. Filtration yielded 9 g. of an off-white solid, M.P. 8l-83 C. an amine of the formula:

4.54 g. (0.01 mole) of this amine and 3.5 g. (0.1 mole) of the sulfonyl chloride of Orange II, a dye of the were allowed to stand overnight at room temperature in 100 ml. of pyridine. The reaction mixture was then heated on the steam bath for 30 minutes, allowed to cool and poured into 500 ml. of 10% NCl and 50 g. of ice. The resulting solid was ltered and recrystallized from ethyl acetate-methanol to yield 3.6 g. of an orange solid, M.P. 19l-193 C. of the formula:

EXAMPLE 6` The procedure of Example 2 was repeated, substituting n-CmHaqNHz for the dodecylamine to obtain the cornpound of Formula 20.

EXAMPLE 7 g. of sodium carbonate was dissolved in 500 m1. of Water. 57.3 g. of sulfanilic acid monohydrate was then slowly added. After all of this acid was dissolved, the resulting solution was cooled to 0 C. and 22.5 g. of sodium nitrite was added. After the sodium nitrite had dissolved, the resulting solution was poured into a mixture of 60.0 ml. of 37% HCl and 300 g. of ice to form a diazonium salt of the formula:

Boas-@ Ni@ After formation of this diazonium salt, the reaction mixture was poured into a water-acetone solution of 15.9 g. of sodium carbonate and 69.6 g. of:

The resulting mixture was allowed to stand for several hours, and then filtered to yield g. of:

HO N/ To a stirred slurry of 20 g. of this last-named compound in 50 ml. of water, was added 20.0 ml. of n-propylamine. The resulting mixture was reiluxed with stirring overnight. Excess propylamine was boiled off and the remaining mixture was poured into 20% NCI. After filtration and recrystallization, 15.5 g. of the corresponding amide was obtained, M.P. 272-274 C. of the formula:

10.4 g. of this amide, 50.0 ml. of chlorobenzene, 5.0 ml. of thionyl chloride and 4.0 ml. of N,Ndimethylform amide were heated on a steam bath for one hour. The solvent was then removed by evaporation with a stream of nitrogen and the resulting mixture was triturated with hexanebenzene. Filtration and recrystallization from benzene yielded 4 g. of a compound, M.P. 18S-18T7 C. of the formula:

i-I-C 0 NHCaH 3.4 g. of this compound and 3.4 g. of an amine of the formula:

(prepared in the manner described in Example 5) were reliuxed overnight in 50 ml. of dry benzene. The mixture 31 was then cooled and the resulting solid collected and crystallized from benzene to yield 4 g. of a compound, M.P. 13S-135 C. ofthe formula:

CONHCQH:

4.0 g. of this last-named compound in 50 ml. of dichloromethane was reacted with a large excess of boron tribromide and the reaction mixture was then allowed to stand overnight at room temperature. Water was added to destroy excess boron tribromide and the mixture was then stirred under nitrogen for one hour and filtered. The resulting solid residue was stirred in hot water and filtered. Recrystallization from benzene-hexane yielded 2.() g. of the compound of Formula 21, yellow crystals, M.P. 138- 140 C.

EXAMPLE 8 15 g. of 4-fluoro-5-nitro-aniline, 35.0 grams of stearoyl chloride and 8.4 g. of sodium bicarbonate were stirred overnight at room temperature. The reaction mixture was then reiiuxed and the insoluble inorganic salts were filtered off. Upon cooling of the filtrate, an olf-white solid was obtained, M.P. 82-83 C., having the formula:

30 g. of 3-carboxy-4-methoxy-analine was added to 75.0 g. of the -stearamido-Z-fluoro-nitrobenzene (prepared above) and 45.0 g. of potassium acetate in 225 ml. of dimethyl sulfoxide. The resulting mixture was stirred over a weekend under a ow of nitrogen while maintaining the temperature at about 100 C. It was then poured into a large amount of cold water and the resulting precipitate was filtered, washed with water and a small amount of ethanol. This crude product was then recrystallized from acetic acid tov yield 36 g. of a yellow solid, M.P. 186-187 C., of the formula:

n-o Hat-o o Nn--NHQ-oom N02 oon 4.0 g. of the last-mentioned compound was hydrogenated in ethanol with a Pd/BaSO, catalyst to reduce the nitro group to an amino substituent. Following hydrogenation for about two hours, the product was filtered and quickly cooled to obtain 3 g. of the amine, a nearly white solid, M.P. 115 C. 7.0 g. of this amine was added to 4.7 g. of 4'-(sulfonyl-chloride)phenylaxo2naphthol in 100 ml. of pyridine under nitrogen. The mixture was allowed to stand overnight at room temperature. It was then heated on a steam cone for 30 minutes, then poured into 600 ml. of HC1, filtered and then rinsed with water and a small amount of methanol. The resulting solid was next triturated with warm methylene chloride and filtered to 32 yield 4.6 g. of a yellow solid, M.P. l38140 C., of the formula:

5.0 g. of the last-named compound was added to an unmeasured amount (about 60 ml.) of methylene chloride and 15 ml. of boron tribromide. The mixture was stirred overnight. The starting -material went into solution as it complexed with the boron trbromide. The complex was decomposed with water, then triturated with hot water, methanol and hexane to yield 4.6 g. of the compound of Formula 16, a yellow solid, M.P. 260 C.

EXAMPLE 9 5.0 cc. of a dispersion containing a 10:20:11 ratio, by weight, of the compound of Formula 19, N,Ndiethyl decanamide and gelatin, was mixed with 13 cc. of water, 5 cc. of a colloidal silver precipitating agent mixture containing .08 g. of Ag/ cc. of water, 2 cc. of 1% aqueous Triton X-100" (trademark of Rohm & Haas Co., for a nonionic isooctyl phenyl polyethoxy ethanol dispersing agent), and 1 cc. of 5% aqueous ethanol. The resulting mixture was coated on a cellulose acetate support at 10 feet per minute at 40 C. After this coating had dried, a mixture of 4 cc. of a blue-sensitive silver iodobromide emulsion, 32 cc. of Water and 2 cc. of 1% Triton X-100 was coated thereover at the same speed and temperature to provide a photosensitive element of FIG. 3.

The eicacy of a system using a photosensitive element prepared in the foregoing manner was iirst established by typical testing procedures wherein the ability of the color-providing material to transfer from unexposed areas was conlirmed. In such testing procedures, no attempt is ymade to obtain an image and the unexposed element is imbibed with a processing composition containing no developer while in superposition with a dyeable stratum. 1% Triton X100 was coated thereover at the same speed and temperature to provide a photosensitive element of FIG. 3. This unexposed element was imbibed with an aqueous alkaline processing composition containing no silver halide developer to establish that transfer could be eiected in terms of unexposed areas. This was ascertained by spreading between the unexposed element and a superposed dyeable stratum at a gap of .0024" a composition comprising the following proportions of ingredients:

Water i ......cc 100.0 Hydroxyethyl cellulose g 3.9 Sodium hydroxide g-- 5.0 Sodium thiosulfate g-.. 4.0

Following an imbibition period of about two minutes, the respective elements were separated to reveal a uniform dense orange dye transfer image.

33 EXAMPLE 1o A photosensitive element similar to that prepared in the above example was prepared by coating onto a cellulose acetate support at a rate of feet per minute a mixture containing 10 cc. of 2% cellulose acetate hydrogen phthalate in acetone, 3.5 cc. of the aqueous colloidal silver mixture of Example 9 in cellulose diacetate and 1.5 g. of the compound of Formula 19; and thereafter coating onto the thus formed layer at the same rate a mixture containing 4.0 cc. of a panchromatic silver halide emulsion, 24.0 cc. of water and 1.0 cc. of 2% Aerosol O.T. (trademark of American Cyanamid Co. for a wetting agent, dioctyl sodium sulfosuccinate). This photosensitive element was exposed and then developed by spreading between the thus exposed element and a superposed dyeable sheet material at a gap of .0024 a processing composition containing the following proportions of ingredients:

Water cc 100.0 Hydroxyethyl cellulose g 3.9 Sodium hydroxide g-- 5.0 Sodium thiosulfate g-- 2.0 Triptycene diol g 1.0

After an imbibition period of about two minutes, the elements were separated to reveal a positive dye image.

In the above example, it will be observed that a low mobility developer was employed to obviate the redox reaction previously described and thereby obtain a positive dye transfer image. The following two examples together illustrate the use of a scavenger to obtain a positive dye transfer image.

EXAMPLE l1 Over this was coated a gelatin layer containing a calculated coverage of 100 mgm. per square foot of a bluesensitive silver iodobromide emulsion to provide a photosensitive element as shown in FIG. 4. This element was then exposed and developed by spreading between the thus exposed element and a superposed dyeable sheet material at a gap of .0026 a processing composition containing the following proportions of ingredients:

Water CC 100.0

Hydroxyethyl cellulose g 3.9 Sodium hydroxide g-.. 5.0 Sodium thiosulfate g-- 2.0 Sodium sulte g-- 2.0 Metol g` 1.6

After an imbibition time of about -two minutes, the elements were separated to reveal a positive dye transfer image.

34 EXAMPLE 12 A photosensitive element prepared in the manner described in Example 9 (containing no scavenger) was exposed and developed in the manner described in Example 11.

When the elements were sepanated following imbibition, dye had transferred in both exposed and unexposed areas so that no image formation was observable.

The following example illustrates the concept of employing a relatively immobile developer in the photosensitive element to obtain a positive transfer image, it being observed that the same compound employed as the scavenger in Example 11 was here employed as the developer.

EXAMPLE 13 A photosensitive element was prepared as in the foregoing examples except that the compound previously employed in Example 11 as the scavenger was included in the silver halide emulsion layer at a calculated coverage of 68 mgm. per square foot, the silver halide also being at a calculated coverage of 68 mgm. per square foot. This element was exposed and developed in the manner described in the previous examples with a developing composition containing the following proportions of ingredients:

Water cc 100.0 Hydroxyethyl cellulose g-.. 3.9 Sodium hydroxide g 5.0 Sodium thiosulfate g 1.0

The gap employed was .0016. After two minutes the elements were separated to reveal a positive dye image.

In the preceding description pertaining to the embodiment employing the compounds of Formula C, reference has been made to the use of silver-precipitating nuclei to render the soluble silver complex reducible and the color-providing material in turn oxidized to effect the desired ring-closure and elimination of the color-providing moiety. However, if the color-providing material is a non-discriminating silver halide developer, silver-precipitating nuclei need not be employed. As will be apparent to those skilled in the art, the compounds of Formula C may be rendered non-discriminating by the presence of various substituents on one of the aromatic rings formed by A and A1, e.g. the substitution of an hydroxyl or amine radical ortho to one of the X and X2 moieties. The use of such non-discriminating developercolor-providing materials is therefore contemplated by this invention.

In the foregoing description, examples of monoazo, disazo and anthraquinone dyes have been recited. However, as was mentioned earlier, the color-providing moiety is not restricted to complete dyes such as those disclosed. Included within the eld of useful color-providing materials are those which are initially colorless or of a color other than that ultimately desired in a particular environment, but which provide the desired color during or subsequent to transfer image formation, e.g., upon a change in environment and/or upon chemical reaction. This change of environment may, for example, be a change in pH, e.g., to an acid environment. Color-providing materials of this nature include indicator dyes, leuco dyes, and carbinols of basic dyes. Also included within the scope of this invention are incomplete dyes or color formers which may react with another substance, e.g., subsequent to transfer to the image-receiving layer, to form a dye image. In the later instance, it will be appreciated that with the compounds of Formula B, this moiety must not be reactable with the oxidized color developer so as to preclude ring-closure and release of the diifusible color-providing moiety.

By way of example, such materials include color coupiers of the phenol and naphthol series in which the carbon atom para to the hydroxy group is blocked by an appropriate group, eg., an alkyl group, so as to preclude coupling with oxidized color developer. Such compounds will however couple ortho to the hydroxy group with a diazonium salt to form an azo dye. The diazonium salt may be contained on the image-receiving element to effect azo dye formation following elimination and subsequent transfer thereto of the color coupler, or dyerformation may be effected by a separate treatment following transfer. Another class of useful materials of this nature are cyanine dye precursors, eg., compounds which in alkali provide an active methine coupler.

The preparation of negative transfer images by the aforementioned redox reaction is described and claimed in the copending application of Stanley M. Bloom and Robert K. Stephens, Ser. No. 655,436 filed concurrently.

Since certain changes may be made in the above product and process without departing from the scope of the invention herein involved, it is intended that all matter f contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. The process of forming transfer images in color which comprises developing a photosensitive element containing an exposed light-sensitive silver halide emulsion with an aqueous alkaline processing composition in the presence of a non-diffusible compound containing a colorproviding moiety; as a function of said developing step providing an imagewise reaction product of said compound, said reaction product being capable of auto-react ing intramolecularly to effect ring-closure and to eliminate said color-providing moiety, said eliminated moiety being diffusible in said processing composition; allowing said reaction product to auto-react to eliminate said colorproviding moiety; forming an imagewise distribution of said eliminated color-providing moiety; and transferring at least part of said imagewise distribution of diffusible color-providing material, by imbition, to a superposed stratum to form a color transfer image thereon.

2. A process as defined in claim 1 wherein a color image the reverse of said transfer image is formed in said photosensitive element.

3. A process as defined in claim 1 wherein said transfer image is a positive image.

4. A process as defined in claim 1 wherein said nondiffusible compound is capable of reacting with the oxidation product of an aromatic primary amino color developer, said color developer is present in said processing composition, and said reaction product which auto-reacts intramolecularly to eliminate said diffusible color-providing moiety comprises the product obtained by reacting said compound with oxidized color developer obtained as a function of development of said emulsion.

5. A process as defined in claim 4 wherein said nondiffusible compound is contained in said photosensitive element in a layer contiguous with said emulsion.

6. A process as defined in claim 4 -wherein said color developer is contained initially in said photosensitive element and its presence in said processing composition is effected by contacting said element with said aqueous processing composition medium.

7. A process as defined in claim 3 wherein said nondiffusible compound is also a silver halide developing agent, said compound lbeing contained in said photosensitive element in a layer contiguous with said emulsion, and said reaction product which auto-reacts intramolecularly to eliminate said diffusible color-providing material comprises the oxidation product obtained by the steps of forming an imagewise distribution of a soluble silver complex as a function of said development and transferring said distribution to said non-diffusible compound where said compound and said silver complex react to form said oxidation product.

8. A process as defined in claim 1 wherein said nondiffusible compound is of the formula:

1 'l`- R Rc1-1i 1 i I /3-N-Y-D wherein:

A represents the atoms necessary to complete an aromatic ring;

D is a color-providing moiety;

Z represents a coupling position selected from the group consisting of hydrogen and radicals replaceable by oxidized aromatic amino color developer; or an aromatic amino radical having a free position ortho to the amino substituent;

Y is a substituent which completes an amide with and reduces the basic character of the 3-amino substituent bonded thereto, said Y substituent further being a divalent radical linking said D moiety to said 3-nitrogen atom;

X is hydroxy, a primary, secondary or tertiary amino,

or, when said Z moiety contains a p-hydroxy or pamino substituent, X may be hydrogen or the substituent R;

R is an anchoring moiety rendering said compound non-diffusible;

R1 is hydrogen, alkyl or substituted alkyl; and

n is positive integer from 1 to 2, provided that when said X and R1 substituents alone or together cornprise an anchoring moiety rendering the compound non-difusible, or when said Z moiety comprises an aromatic nucleus contributing an anchoring moiety alone or in conjunction with the remainder of said molecule, n may be 1, but when said substitue-nts do not contribute an anchoring moiety, n must be 2.

9. The process of forming transfer images in color which comprises developing a photosensitive element including at least one exposed light-sensitive silver halide emulsion with an aromatic primary amino color developer; forming as a function of said development an imagewise distribution of oxidized color developer; reacting said imagewise distribution of oxidized color developer with an initially non-diffusible compound containing a colorproviding moiety to form a non-diffusible reaction product of said two compounds, said reaction product being capable of auto-reacting intramolecularly to effect ringclosure and to eliminate said color-providing moiety; allowing said reaction product to auto-react intramolecularly to effect ring-closure and to eliminate said color providing moiety; forming an imagewise distribution of said eliminated color-providing moiety in areas corresponding to areas of reaction between said oxidized color developer and said compound; and transferring at least part of said imagewise distribution, by imbibiton, to a superposed stratum to form a color transfer image thereon.

10. A process as defined in claim 9 wherein said imagelwise reaction between oxidized developer and said nondiffusible compound is in terms of exposed areas of said emulsion and said color transfer image is a negative image.

11. A process as defined in claim 9 wherein said imagewise reaction between oxidized developer and said nondiifusible compound is in terms of unexposed areas of said emulsion and said color transfer image is a positive image.

12. A process as defined in claim 10 wherein said irnagewise reaction in terms of unexposed areas of said emulsion is effected by the steps of reacting oxidized developer formed as a function of development of said emulsion with a non-diffusible color coupler to form a non-diffusible reaction product; oxidizing unexhausted color developer by contact with a prefogged silver halide emulsion to form an imagewise distribution of oxidized developer in terms of unexposed areas of said first-named emulsion as a function thereof; and thereafter reacting said imagewise distribution of oxidized developer with said compound to provide said positive transfer image.

13. A process as dened in claim 9 wherein said nondiifusible compound is of the formula:

(TF1) 'A l wherein:

A represents the atoms necessary to complete an aromatic ring;

D is a dye moiety;

Z1 represents a coupling position selected from the group consisting of hydrogen and radicals replaceable by oxidized aromatic amino color developer;

Y is a substituent which completes an amide with and reduces the basic character of the 3-nitrogen substituent bonded thereto, said Y substituent further being a divalent radical linking said D moiety to said 3- nitrogen atom;

X1 is hydroxy, or a primary, secondary or tertiary amino substituent;

R is an anchoring moiety rendering said compound non-diffusible;

R1 is hydrogen, alkyl or substituted alkyl;

n is a positive integer from 1 to 2, provided that when said Xl and R1 substituents alone or together comprise an anchoring moiety rendering the compound non-diffusible, n may be 1, lbut when said substituents do not contribute an anchoring moiety, n must be 2.

14. The process of forming positive color transfer images which comprises exposing a photosensitive element including at least one light-sensitive silver halide emulsion having associated therewith a non-diifusible color-providing material which is capable of providing an oxidation product which can auto-react intramolecularly to effect ring-closure and to eliminate the color-providing moiety of said material for transfer; developing said exposed silver halide emulsion with an aqueous alkaline processing composition including a silver halide solvent and a silver halide developing agent; forming as a function of development an imagewise distribution of a soluble silver complex in terms of unexposed areas of said emulsion; contacting said non-diffusible color-providing material with said imagewise distribution of soluble silver complex to reduce said silver complex and as a function thereof forming an imagewise distribution of oxidized color-providing material; allowing said oxidized material to auto-react intramolecularly to eliminate said color-providing moiety, thereby forming an imagewise distribution of diifusible color-providing moiety in terms of unexposed areas of said emulsion; and transferring said imagewise distribution of said color-providing moiety to a superposed stratum to impart thereto a positive color transfer image.

15. A process as defined in claim 14. wherein said imagewise distribution of soluble silver complex contacts said non-dilfusible color-providing material in the presence of silver-precipitating nuclei to effect said reduction of said silver complex and as a function thereof said formation of an imagewise distribution of oxidized colorproviding material.

16. A process as defined in claim 14 wherein said silver halide developing agent is a relatively immobile compound which, at least in its oxidized form, cannot migrate to said non-diffusible color-providing material in any appreciable amount during processing.

17. A process as defined in claim 14 wherein said silver halide developing agent is an immobile developing agent which is present initially in said photosensitive element.

18. A process as dened in claim 14 including in said photosensitive element a scavenger for oxidized silver halide developing agent, said scavenger comprising a material for reducing oxidized developing agent formed as a function of development of said silver halide emulsion.

19. A process as defined in claim 14 wherein said nondiffusible color-providing material comprises a compound of the formula:

wherein:

each of A and A1 represents the atoms necessary to complete an aromatic ring;

D is a color-providing moiety;

Y is a substituent which completes an amide with and reduces the basic character of the 3-amino substituent bonded thereto, said Y substituent further being a divalent radical linking said D moiety to said 3-nitrogen atom;

X and X2 each is hydrogen, hydroxy, amino of the substituent R, provided that at least one of X and X2 must be hydroxy or amino;

R and R4 each represents an anchoring moiety rendering said compound non-diffusible;

R1 is hydrogen, alkyl or substituted alkyl; and nand n1 each is l or 2, provided that when R1 is an alkyl radical or X or X2 is a secondary or tertiary amino comprising an anchoring moiety rendering said compound non-ditfusible or when R1, X and X2 together contribute an anchoring moiety, n and n1 may be 1, but when said substituents alone or together do not contribute an anchoring moiety at least one of n and n1 must be 2.

20. A process as defined in claim 14 wherein said nondifusible color-providing material is a compound of the formula:

wherein:

each of R and R4 comprises an amide of at least 13 carbon atoms, said amide being bonded directly to a nuclear carbon atom of the shown benzene moiety or linked thereto through a phenylene or alkylene substituent; each of n and nl is 1 or 2, provided that at least one of said n and nl is 2; and D is a monoazo, disazo or anthraquinone dye moiety. 21. A process as dened in claim 14 wherein said nondifusible color-providing material is a compound selected

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