CA1061363A - Acylhydrazinothiourea derivatives as photographic nucleating agents - Google Patents

Abstract

Abstract of the Disclosure A radiation-sensitive composition is disclosed including silver halide grains capable of forming an inter-nal latent image and an acylhydrazinophenylthiourea nuclat-ing agent. This composition can be used as a coating on a support to form a photographic element.

Description

The present invention is directed to novel photographic nucleating agents and to photographic elements and radiation- ;~
sensitive compositions containing such elements. ~ore specifically, ;~
this invention is directed to novel acylhydrazinophenylthioureas and to elements and compositions including such compounds and silver halide grains capable o~ ~orming internal latent images.
Photographic elements which produce images having an optical density directly related to the radiation received on exposure are said to be negative working. A positive photographic image can be formed by producing a negative photographic image and then forming a second photographic image which is a negative of the ~irst negative--that is, a positive image. The advantage of forming a positive photo-graphic image directly has long been appreciated in the art. ;
A direct-positive image is understood in photography to be a posltive image that is ~ormed without first forming a nega-tive image.
A conventional approach to forming direct-positive images is to use photographic elements employing internal latent image forming silver halide grains. After imagewise exposure, the silver halide grains are developed with a surface developer--that is, one that will leave the latent lmage sites within the silver halide grains substantially unrevealed. Simultaneously, either by uniform light expos- , -ure or by the use of a nucleating agent, the silver halide grains are sub~ected to development conditions that would cause fogging of a negative-working photographic element.
The internal latent image forming silver halide grains which ~ -received actinic radiation during imagewise exposure develop under these conditions at a comparatively slow rate as compared to the internal latent image ~orming silver halide ;

grains not exposed. The result is a direct-positive silver image. In color photography the oxidized developer that is

-2- ~

, ' . ` .

~6~63 produced during development is used to produce a correspond-ing positive dye image. Multi-color direct-positive photo-graphic images based on the above-described "internal image reversal" process have been investigated extensively in connection with image-transfer photography.
The term "nucleating agent" is employed herein in its art recognized usage to mean a fogging agent capable of permitting the selective development of internal image i~ ;
forming silver halide grains which have not been image-wise exposed, in preference to the development of silver halide grains having an internal latent image formed by ~
imagewise exposure. Nucleating agents are fogging agents ;-which perform essentially the same function achieved by unirorm light exposure during development in internal image ' reversal processes.
; Substituted hydrazines have been extensively investigated as nucleating agents for forming direct-positive photographic images with internal latent image emulsions.
Illustrative patents directed to the use of hydrazines in ~;
20 forming direct-positive photographic images are Ives U.S.
Patent 2,563,785 and 2,588,982, issued August 7, 1951 and March 11, 1952, respectively; Whitmore U.S. Patent 3,227,552, ~.
issued January Ll, 1966; and Knott and Williams British Patent 1,269,640, published April 6, 1972. Ives as well as ;
Knott and Williams teach the incorporation of their nucleat- `
ing agents in photographic developers. The nucleating agents of Whitmore can be incorporated directly within a photographic element or in an image-receiving element as well as in the photographic developer. Whitmore teaches the use of substituted hydrazine nucleating agents in image-transfer type photographic elements.

-3- ~

i, .'.
. . . ~

~Q6~363 .
In considering the formation of direct-positive photographic images using conventional substituted hydrazine nucleating agents of the type disclosed above by Ives, Whitmore and Xnott et al, a number of disadvantages have been identified. One disadvantage has stemmed from the '~
tendency of incorporated hydrazine derivatives when used ln '~
conventional large quantities to liberate nitrogen gas in the course of nucleating silver halide. The liberated gas can result in bubbles being trapped within the binder for ~:
the photographic element. The bubbles can produce optical distortions or even cause discontinuities in one or more ~
layers of the photographic element, thereby degrading the `
photographic image.
Another disadvantage Or conventional substituted hydrazine nucleating agents has been their temperature de- .
pendence. Specifically, photographic speeds have been noted s-to drop as processing temperatures increase. While process-ing temperatures can be controlled precisely in many photo-graphic applications, this can be inconvenient in many instances and impossible in others, such as image-transfer photography, where processing frequently occurs at approxi-mately the ambient temperature of the scene being photo-graphed.
Another approach toward finding useful nucleating agents has been to synthesize heterocyclic nitrogen quater-nary salts, such as disclosed by Kurtz and Harbison V.S. n Patent 3,734,738, issued May 22, 1973, and Kurtz and Hesel~
tine V.S. Patent 3~719g494~ issued March 6, 1973. Similarly, Lincoln and Heseltine U.S. Patents 3,615,615 and 3,759,901.
issued April 13, 1970 and September 18, 1973, teach the use of novel N-hydrazonoalkyl substituted heterocylic nitrogen _4_ ";

~, .
~, ~

~061363 quaterna~y salts as nucleating agents. Whiie these hetero-cylic nucleating agents have reduced the concentrations required somewhat, they have generally shared the disadvan-tages o~ substituted hydrazine nucleating agents. Further, these quaternary salts can be disadvantageous in absorbing light within the visible spectrum.
This invention has as its purpose to provide photographic compositions and elements which are less tem-perature dependent. Specifically, this invention provides photographic compositions and elements useful in forming direct-positive lmages and which show diminished speed loss and in some instances speed galn with increasing processing temperatures. This invention also has as its purpose to obviate optical distortions due to nitrogen gas liberation in photographic compositions and elements. Additionally, -¦~ this invention has as lts purpose providing photographic compositions and elements with more e~fective nucleating agents. These more effective nucleating agents can be employed in lower concentrations than have heretofore been ¦ practiced in the art. Further, this invention provides photographic elements and compositions having nucleating agents dlrectly incorporated therein rather than in a devel-i oper composition. These nucleating agents can be adsorbed t ,1 .

`:

.~ .

~ ~5~

.
. . .
~, .

.363 to the surface of internal latent image-forming silver halide grains, but they do not absorb visible light. This invention further providec an advantage in allowing combina-tions of nucleating agents to be employed to control the speed of direct-positive silver halide compositions and elements. :~
In one aspect this invention is directed to a radiation-sensitive composition comprising silver halide grains capable of forming an internal latent image when coated in a photographic element and exposed to actinic ..
radiation and an acylhydrazinophenylthiourea nucleating agent. ~
In another aspect this invention is directed to .: ~ :

acylhydrazinophenylthioureas of the formula Il H H I 11 H
1. R-C-N-N-R1-N--C-N-R~
wherein R is hydrogen; an alkyl, cycloalkyl, haloalkyl, alkoxy-alkyl, phenylalkyl substituent or a phenyl nucleus having a Hammett ~ .
sigma-value-derived electron withdra~ing characteristlc more positive than -0.3; Rl is a phenylene or alkyl, :
halo- or alkoxy-substituted phenylene group; R2 is an ,''" ~

~: '. " '' , ,.
`' '~'' -6- ~.

~ ~6~1L363 ~

alkyl, haloalkyl, alkoxyalkyl or phenylalkyl substituent having from 1 to 18 carbon atoms; a cycloalkyl substituent; naphthyl, a phenyl nucleus having a Hammett signa-vaiue-derived elec-tron withdrawing characteristic less positive than +0.50 or O .

I. -R1-N-N-C-R , R3 is hydrogen, benzyl, alkoxybenzyl, halobenzyl or alkyl-benzyl, the alkyl moieties, except as otherwise noted~ in each instance include from 1 to 6 carbon atoms; and the cyclo-alkyl moieties have from 3 to 10 carbon atoms.
In another speci~ic aspect this invention is directed to an improved photographic element comprised o~ a support and, as a coating thereon, a radiatlon-sensitive silver halide emulsion layer comprised o~ silver halide grains capable of ~orming an internal latent image. The improve-ment is represented by the presence within the radiation-sensitive layer of an acylhydrazinophenylthiourea nucleating agent. ~se~ul agents o~ this type include, for example, compounds of formula I above.
Our invention can be better appreciated by re~er-ence to the following detailed description.
We have discovered that superior direct-positive image-forming photographic composikions and elements can be ;
produced by employing an acylhydrazinophenylthiourea nucleat-ing age~t in combination with internal latent image silver halide grains. Any acylhydrazinophenylthiourea can be employed as a nucleating ~gent.

~ -7- :

.,;

~ 6~L363 From formula I it is apparent that in the acyl group of the acylhydrazinophenylthioureas R can be the residue of a carboxylic acid, such as one of the acyclic carboxylic acids, including formic acid, acetic acid, ~:
propionic acid, butyric acid, higher homologues of these acids having up to about seven carbon atoms and halogen, alkoxy, phenyl and e~uivalent substituted derivatives there-of. In a prererred form the acyl group is formed by en ~"

', ' ' .

,' ~ . ' ~ ' .

C
.. ..

-7a- .

"i,..

~6~363 ~
~ , acyclic aliphatic carboxylic acid having fro,m 1 to 5 carbon atoms in its unsubstituted form. The alkyl moieties in the substitutents to the carboxylic ac~tds~are contemplat~ed to have from 1 tQ 6 carbon atoms, preferably from 1 to 4 carbon atoms.
In addition to the ~cyclic aliphatic carboxylic acids, it is recognized that ~he carboxylic acid can be chosen so that R is a cyclic aliphatic group having from about 3 to 10 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclohexyl, cyclooctyl, cyclo-decyl and bridged ring variations, such as bornyl-and iso-bornyl groups. Cyclohexyl is a specifically preferred cycloalkyl substituent. The use of alkoxy, cyano, halogen and equivalent substituted cycloalkyl substituents is contem-plated.
In still another iorm R can be the residue of an aromatic carboxylic acid, such as benzoic acid and substi- ~
tuted derivatives thereof R can take the form of a phenyl ~ ~-nucleus which is either electron donating (electropositive) or electron withdrawing (electronegative), however phenyl nuclei which are highly electron donating may produce inferior nucleating agents. The electron withdrawing or electron donating characteristic of a specific phenyl nucleus can be assessed by reference to Hammett sigma values. The phenyl nucleus can be assigned a Hammett sigma-value-derived electron withdrawing characteristic which is the algebraic ~um of the Hammett sigma values of its substituents (i.e., those of the substituents, if any, to the phenyl group).
For example, the Hammett sigma values of any substituents to the phenyl ring of the phenyl nucleus can be determined algebraically simply by determining from the literature the known Hammett sigma values for each substituent and obtain---8- `

.. ... ...... ~
". ..

6~363 .
ing the algebraic sum thereof. Electron withdrawi~g substi-tuents are assigned positive sigma values while electron donating substituents are assigned negative sigma values. ~t In a preferred form R is a phenyl nucleus having a Hammett sigma-value-derived electron withdrawing characteristic more positive than -0.3. `
Exemplary meta and para sigma values and procedures for their determinatijon are set forth by J. Hine in Physi-cal Organic Chemistry, 2nd edition, p. 87, published 1962; ~ -H. VanBekkum, P. E. Verkade and B. M. Wepster in Rec. Trav.
Chim, volume 78, page 815, published l95g; by P. R. Wells in Chem Revs., volume 63, page 171, published 1963, by H. H.
Jaffe, Chem. Revs., volume 53, page 191, published 1953; by M. J. S. De~ar and P. J. Grisdale in J. Amer. Chem. Soc., `
volume 84, page 3548, published 1962; and by Barlin and Perrin in Quart. Revs., volume 20, page 75 et seq., pub-lished 1966. For the purposes of this invention, ortho substituents to the phenyl ring can be assigned the pub-lished ~ sigma values.
20 - In a preferred form R can be the residue of an aromatic carboxylic acid such as benzoic acid; alkyl, halo-, cyano or alkoxy substituted benzoic acid or an equivalent thereof. Where R is the residue of a substituted benzoic acid, it is preferred that the benzoic acid be para or 4 ring position substituted. ~he alkyl moieties of the ring substituents preferably have from 1 to 6 carbon atoms.
~luoro, c}lloro, bromo and iodo halogen ring substituents are specifically contemplated.
The Rl group in formula I can be an ortho-, meta-or ara-phenylene group or a substituted equivalent thereof.
Alkoxy, alkyl and halo-substituted phenylene groups are _g_ ~

~" .

~61363 , specifically contemplated. Compounds wherein Rl is a para-phenylene group have been found to be more effective as nucleating agents as compared to the meta- and ortho- iso- ~
meric forms. We specifically prefer R to be a para-phenylene `
group or a para-phenylene group which is substituted in the 3 ring position (with respect to the thiourea moiety) with an alkoxy, alkyl or halo-substituent. Exemplary of preferred phenylene substituents are alkoxy substituents having from l to 6 carbon atoms, alkyl substituents having from 1 to 6 carbon atoms, fluoro-, chloro-, bromo- and iodo-substituents. Rl groups having from 6 to 10 total carbon atoms are specifically prererred.
Rererring again to formula I, it is apparent that R2 can take a variety of forms. In one specifically contem-plated form R can be an alkyl group or a substituted alkyl ;
group, such as a haloalkyl group, alkoxyalkyl group, phenyl-alkyl group, or equivalent group, having a total of up to 18, preferably up to 12, carbon atoms. Specifically, R2 can take the form of a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl or higher homologue group having up to 18 total carbon atoms; a fluoro-, chloro-, bromo- or iodo-substituted derivative thereof; a methoxy, ethoxy, propoxy, butoxy, or higher homologue alkoxy substi- i tuted derivative thereof, wherein the total number of carbon atoms are necessarily at least two up to 18; and a phenyl substituted derivative thereof, wherein the total number of carbon atoms is necessarily at least 7, as in the case Or benzyl, up to about 18.
In addition to the acyclic aliphatic and aromatic 3o forms of R2 discussed above, it is also contemplated that R2 can take the form of a cyclic aliphatic substituent, such as , a cycloalkyl substituent having from 3 to 10 carbon atoms.
-9a-.,, '' '',:

~61363 The use of cyclopropylg cyclobutyl, cyclopentyl, cyclohexyl, methylcyclohexyl, cyclooctyl, cyclodecyl and~ bridged ring variations, such as bornyl and isobornyl groups, is contemplat-ed. Cyclohexyl is a preferred cycloalkyl substituent. The use of alkoxy, cyano, halogen and equi~alent substituted cyclo-'~ ' "
alkyl substituents is contemplated.
R2 can also be an aromatic substituent, such as phenyl 1 ~ ~
or naphthyl (i.e., l-naphthyl or 2-naphthyl) or an equivalent -aromatic group--e.g., 1-, 2- or 9-anthryl, etc. In a pre-ferred form R2 can take the form of a phenyl nucleus which is either electron donating or electron withdrawing, however phenyl -.
.. .i . - .
nuclei which are highly electron withdrawing may produce infer-ior nucleating agents. For example, the 4-cyanophenyl nucleus of 1-[4-(2-formylhydrazino)phenyl]-3-(4-cyanophenyl)thiourea ~NA-22) is belleved to account ror the relatively inferior ;
(though fully operative) performance observed for this nucleat-ing agent. For this reason, I prefer R2 to be a phenyl nucleus having a Hammett sigma-value-derived electron withdrawing characteristic less positive than +0.50, I specifically con- `~
template R2 being chosen from among phenyl nuclei having cyano, fluoro-, chloro-, bromo-, iodo-, alkyl groups having from 1 to .
6 carbon atoms and alkoxy groups having from 1 to 6 carbon atoms, as phenyl ring substituents. Para or 4 ring posi-tion phenyl~-ring substituents are preferred. ~;
In one form R3 represents an unsubstituted benzyl `~
group or substituted equivalents thereof, such as alkyl, halo-- or alkoxy-substituted benzyl groups. In the preferred form no more than 6 and, most preferably, no more than 4 carbon atoms are contributed by substituents to the benzyl .,; .
group. Substituents to the benzyl group are preferably para-substituents. Specifically preferred benzyl substituents are formed by unsubstituted, 4-halo-substituted, 4-methoxy-substituted and 4-methyl-substituted benzyl groups. In i -another specifically preferred form R3 represents hydrogen.

I

~1~36~3~3 ....
From Formula I it is apparent that in one preferred form the acylhydrazinophenylthioureas can be symmetrical com- -pounds--that is, bis(acylhydrazinophenyl)thicureas. Such `
compounds can be prepared by the following procedure: Using as a known starting material 4-nitrophenylhydrazine, this compound can be reacted with a carboxylic acid or halide or anhydride thereof (e.g., benzoic anhydride, formic acid, ~, , .
acetic acid, hexanoyl chloride, etc.) containing the desired ~`~
acyl residue for the acylhydrazinophenylthiourea. Where the carboxylic acid is a liquid it can be used as a solvent for the reaction and an excess of the carboxylic acid is employed.
In any instance a mutual solvent, such as benzene or aceto-nitrile, can be employed. Upon heating to re~lux the 4-nitro-phenylhydrazide of the corresponding carboxylic acid precipi- `

tates from solution. The precipitate can then be dissolved :.
in ethanol and reduced to the corresponding l-acyl-2-(4-amino-phenyl) hydrazine by hydrogenation at room temperature using a palladium catalyst. After evaporating the ethanol, the l-acyl-2-(4-aminophenyl)hydrazine is dissolved in water along 20 with bis-carboxymethyl)trithiocarbonate and the pH is adjusted ~-with sodium carbonate to a level in excess of 8, such as in the range of from 8 to 10. The mixture is stirred and ~
heated to a temperature of from 80 to 95C and then chilled ~;
to obtain the bis-(acylhydrazinophenyl)thiourea as a precipi-tate.
Where it is desired to synthesize an unsymmetrical 7; '~
acylhydrazinophenylthiourea according to this invention, such 1.
as, for example, when R2 is intended to present an alkyl or carbocyclic group including substituted derivatives, the procedure described above is employed through the formation of the desired l-acyl-2-(4-aminophenyl)hydrazine. An isothio~

:.` , .

' ~
-- . _ . . , ~l~61363 cyanate containing the desired alkyl or carbocyclic moiety is dissolved in acetronitrile or ethanol along with the 1-acyl-2-(4-aminophenyl)hydrazine and heated to reflux. The unsymmetrical acylhydrazinophenylthiourea either precipitates or is precipitated by the addition of water and can be removed by filtering.
In those instances where R3 represents a benzyl substituent the l-acyl-2-(4-aminophenyl)hydrazine is dissolved in ethanol, along with benzaldehyde or a desired substituted benzaldehyde and heated to reflux. A Schiff base forms as a precipitate which can be converted to the l-acyl-2-(4-benzyl-aminophenyl)hydrazine by hydrogenation in thejpresence of a platlnum catalyst. Formation of the acylhydrazinophenylthio-urea can be completed by reacting the l-acyl-2-~4-benzylamino-phenyl)hydrazine with an isothiocyanate following the prepara- `
tion of unsymmetrical acylhydrazinophenylthioureas set out above. In a variant form the isothiocyanate can take the form of a l-acyl-2-(4-isothiocyanatophenyl)hydrazine prepared by reacting thiophosgene with the corresponding l-acyl-2-(4- `;
aminophenyl)-hydrazine dissolved in an inert solvent such as benzene.
Illustrative specific acylhydrazinophenylthioureas useful in the practice of this invention include those set -forth below ln ~able I.

, 1~613gi,3 ..
' TABLE I
NA- 1 1,3-Bis[4-(2-~ormylhydrazino)phenyl]-thiourea .
NA- 2 1,3-Bis[4-t2-acetylhydrazino)phenyl]-thiourea NA- 3 1,3-Bis[4-(2-trifluoroacetylhydrazino)~
phenyl]thiourea NA- 4 1,3-Bis[4-(2-butyrylhydrazino)phenyl]- "5,~
thiourea ~:~
;::
~A- 5 1,3-Bis[4-(2-hexanoylhydrazino)phenyl]-thiourea NA- 6 1,3-Bis[4-(2-benzoylhydrazino)phenyl]- :
thiourea .
NA- 7 1,3-Bis[4-(2-o-toluoylhydrazino)phenyl~- .
thiourea NA- 8 1,3-Bis ~4-[2-(2,4-dimethylbenzoyl)hydra- ;, zino]phenyl~thiourea NA- 9 1,3-~is{4-[2-(4-ethylbenzoyl)~
hydrazino]phenyl} thiourea NA-10 1,3-Bis[4-(2-a-naphthoylhydrazinO)-phenyl]thiourea NA-ll 1-[4-(2-~ormylhydrazino)phenyl]-3- . ~
methylthiourea ;~ :
NA-12 1-[4-(2-formylhydrazino)phenyl]-3-butyl~
thiourea ~ ;:
NA-13 1-[4-(2-acetylhydrazino)phenyl]-3-ethyl-thiourea .
NA-14 1-[4-(2-~ormylhydrazino)phenyl]-3-cyclo-hexylthiourea .~
NA-15 1-[4-(2-benzoylhydrazino)phenyl]-3- .: :.
phenylthiourea ~i : .
NA-16 1-~4 (2-formylhydrazino)phenyl]-3 phenylthiourea .
NA-17 - 1-[4-(2-acetylhydrazino)phenyl]-2- ^
phenylthiourea NA-18 1-[4-(2-acetylhydrazino)phenyl]-3-~-naphthylthiourea '";~ .
-13- '`~

~136~363 `~
. ~ .
TABLE I (Cont'd) ~.
NA-19 1-[4-(2-formylhydrazino)phenyl]-3-benzylthiourea ;~
NA-20 1-[4-(2-formylhydrazino)phenyl]-3-heptylthiourea.
NA-21 1-[4-(2-formylhydrazino)phenyl-3-decyl- .
thiourea NA-22 1-[4-(2-formylhydrazino)phenyl]-3-(4-cyanophenyl)thiourea NA-23 1-[4-(2-formylhydrazino)phenyl]-3-(4- -.
methoxyphenyl)thiourea NA-24 1-[4 (2-formylhydrazino)-3-methoxy-phenyl]-3-phenylthiourea .
NA-25 1-[4-(2-formylhydrazino)-3-methoxy-phenyl]-3-butylthioure,a NA-26 1-[4-(2-formylhydrazinol;3-methoxy- ~:
phenyl]-3-cyclohexylthi~u'rea NA-27 1-[4-(2-~ormylhydrazino)-3-methoxy~
phenyl]-3-(4-methoxyphenyl)thiourea ;`
NA-28 1-[4-(2-trifluoroacetylhydrazino)- -;
phenyl]-3-phenylthiourea NA-29 1.-{4-[2-(4-cyanobenzoyl)hydrazino]-phenyl}-3-phenylthiourea `
NA-30 1-{4-[2-(4-chlorobenzoyl)hydrazino~
phenyl}-3-phenylthiourea .
NA-31 1-{4-[2~-(4-fluorobenzoyl)hydrazino]- ,;
phenyl}-3-phenylthiourea !''. ' ' .
NA-32 1-{4-[2-(4-rnethylbenzoyl)hydrazino]-phenyl}-3-phenylthiourea ~. .
NA-33 1-{4-[2-(4-methoxybenzoyl)hydrazino~
phenyl}-3-phenylthiourea :' :
NA-34 1-{4-[2-(4-chlorobenzoyl)hydrazino]-phenyl}-3-benzylthiourea ~ .
NA-35 1-{4-[2-(4-fluorobenzoyl)hydrazino]-phenyl}-3-benzylthiourea NA-36 1-[3-(2-formylhydrazino)phenyl]-3-phenylthiourea NA-37 1-[3-(2-formylhydrazino)phenyl]-3- :
(4-methoxyphenyl)thiourea NA-38 1-[2-(2-formylhydrazino)phenyl]-3-phenylthiourea -14- :

'' ~1363 :

TABLE I (Cont'd) NA-39 1-[4-(2 formylhydrazino~phenyl.
benzyl-3-phenylthiourea NA-40 1-[4-(2-acetylhydrazino)phenylJ~
benzyl-3-phenylthiourea NA-41 1-[4-(2-benzoyihydrazino)phenyl]-1-(2-chlorobenzyl)-3-phenylthiourea : .

NA-42 1-[4-(2-acetylhydrazino)phenyl]-1-(4- .`
methoxybenzyl)-3-phenylthiourea ~-~

NA-43 1-[4-(2-formylhydrazino)phenyl]-1-~4-methylbenzyl)-3-methylthiourea NA-44 1-[4-(2-acetylhydrazino)phenyl]-1-benzyl-3-[4-(2-formylhydrazino)phenyl~
thiourea . .- .

The acylhydrazinophenylthiourea nucleating agents can . ~:
be employed with any conventional photograph~c element capable .~:
of rorming a direct-positlve image contalning at least one radlation-sensitive layer containing silver halide grains capable ;~
.... . .
of ~ormlng an internal latent image upon exposure to actinlc ..
20 radiation. As employed here~n, the terms "internal latent image ;~
silver halide grains" and "silver halide grains capable of ~orming '!''''' an internal latent image" are employed in the art-recognized sene of designating silver halide grains which produce substan- .~
tially higher optical densities when coated, lmagewlse exposed . :
and developed in an ~nternal developer than when comparably coated, exposed and developed in a surface developer. Preferred ~` :
.
internal latent image sllver halide grains are those which when examined according to normal photographic testing techniques, by . ~ :~
coating a test portion on a photographic support at a density o~ ::
from 3 to 4 grams/m2, exposing to a light intensity scale (such as, for example, with a 500 watt tungsten lamp at a distance of 61 cm) for a fixed time between 1 X10 2 and 1 second and developing for 5 minutes at 25~C in Kodak~Developer DK-50 ~ a surface developer) provide a density of at least 0.5 density units less than when 1(~61363 this testing procedure is repeated substltuting rO~ the sur~acedeveloper Xodak~Developer DK-50 containing 0.5 gram per liter Or potassium iodide (an internal developer). The internal latent image silver halide grains most preferred ~or use in the practice of this invention are those which when tested using an internal developer and a sur~ace developer as indicatecl above produce an ; optical density with the internal developer at least 5 times that produced by the surface developer. It ls additionally preferred that the internal latent image silver halide grains produce an optical density of less than 0.4 and, most preferably, less than 0.25 when coated, exposed and developed in surface developer as i~
indicated above--that ls, the silver halide~gjrains are lnitially substantially unfogged and ~ree~o~ latent image on their surface.
The surrace developer re~erred to herein as Kodak~ ¦
Developer DK 50 is described in the Handbook o~ Chemistry and Physics, 30th ed., 1947, Chemical Rubber Publishing Co., Cleveland, Ohio, p. 2558, and has the rollowing composition: I
Water, about 125F ~52C) 500.0 cc ~I -N-methyl-~-aminophenol sulfate 2. 5 g Sodium sulfite, desiccated 30.0 g Hydroquinone 2.5 g `
Sodium metaborate 10.0 g Potassium bromlde 0. 5 g Water to make 1.0 liter.
Internal latent image silver hallde grains whlch can be employed in the practice Or this invention are well known in the art. Patents teaching the use o~ internal l~tent image silver 1~
halide grains in photographic emulsions and elements include Davey ; , et al U~5. Patent 2,592,250, issued May 8, 1952; Porter et al U.S.
Patent 3,206,313, issued September 14, 1965; Milton U.S. Patent 3,761,266, issued September 25, 1973; Ridgway U.S. Patent ; 3.' . . .,";, . ` .
'' . ' ' ' ~
.

..,~
3,586,505, issued June 22, 1971; Gilman et al U.S. Patent 3,772,030, issued November 13, 1973; Gilman et al U.S.
Patent 3,761,267, issued September 25, 1973; and Evans U.S.
Patent 3,761,276, issued September 25, 1973.
The internal latent image silver halide grains preferably contain bromide as the predominant halide. The silver bromide grains can consist essentially of silver bromide ., ~ . , :
or can contain silver bromoiodide, silver chlorobromide, silver `
chlorobromoiodide crystals and mixtures thereof. Internal latent image forming sites can be incorporated into the grains by either physical or chemical internal sensitization. Davey et al, cited above, for example, teaches the physical formation ;~
of internal latent image forming sites by the halide conversion technique. Chemical formation of internal latent image forming sites can be produced through the use of sulfur, gold, selenium, tellurium and/or reduction sensitizers of the type ~;~
described, for example, in Sheppard et al U.S. Patent 1,623,499, ;~
issued April 5, 1927; Waller et al U.S. Patent 2,399,083, issued `;
April 23, 1946; McVeigh U.S. Patent 3,297,447, issued January 10, 1967 and Dunn U.S. Patent 3,297,4~6, issued January 10, ;
1967, as taught in the patents cited in the preceding paragraph.
Internal latent image sites can also be formed through the incorporation of metal dopants, particularly Group VIII plati-num metals such as ruthenium, rhodium, palladium iridium, osmium and platinum, as taught by Berriman U.S. Patent 3,367,778, issued February 6, 1968. The preferred foreign metal ions are polyvalent metal ions which include the above-noted Group VIII
dopants as well as polyvalent metal ions such as lead, antimony, bismuth, arsenic and the like. In highly preferred embodiments, `
the silver halide grains are formed in the presence of bismuth, -lead or iridium ions. In a preferred approach the internal ... . .
' ~ .

~ ~:
lQ6~ 363 ~:
latent image sites can be formed within the silver halide grains during precipitation of silver halide. In an alternate approach a core grain can be formed which is treated to form ~' the internal latent image sites and then a shell deposited over the core grains, as taught by Porter et al, cited above.
The silver halide grains employed in the practice of this invention are preferably monodispersed, and in some embodiments are preferably large-grain emulsions made according to ~7ilgus, German OLS 2,107,118 published September 2, 1971. The monodispersed emulsions are those which comprise silver halide grains having a substantially uniform diameter~ Cenerally, in such emulsions, no more than about 5 percent, by weight, of the silver halide grains smaller than the mean grain size an~/or no more than about 5 percent, by number, o the silver halide grains larger than the mean grain size vary in diameter from the mean grain diameter by more than about 40 percent. Preferred photo-graphic emulsions of this invention comprise silver halide grains, at least 95 percent, by weight, of said grains having a diameter which is within 40 percent, preferably within about 30 percent, of the mean grain diameter. Mean grain diameter, i.e., average grain size, can be determined using conventional methods, e.g., such as projective area as shown in an article by Trivelli and Smith entitled "Empirical Relations between Sensitometric and Size-Frequency Characteristics in Photographic ~ -Emulsion Series" in The Photographic Journal, Vol. LXXIX, 1939 pp. 330-338. The aforementioned uniform size distribution of silver halide grains is a characteristic of the gralns in monodispersed photographic silver halide emulsions. Silver halide grains having a narrow size distribution can be obtained by controlling the conditions at which the silver halide grains are prepared using a doub~e-''' ~6~363 ~

run procedure. In such a procedure, the silver halide grains are prepared by simultaneously running an aqueous solution of a silver ~ -salt, such as silver nitrate, and an aqueous solution of a water-soluble halide, for example, an alkali metal halide such as potassium bromide, into a rapidly agitated aqueous solution of a silver halide peptizer, preferably gelatin, a gelatin derivative ;~
or some other protein peptizer. The pH and the pAg employed in this type of procedure are interrelated. For example, changing .. ~, one while maintaining the other constant at a given temperature ~ ;
can change the size frequency distribution of the silver halide grains which are formed. However, generally the temperature is about 30 to about 90~C, the pH is up to about 9, preferably ll or less, and the pAg is up to about 9.8. Suit~b~e methods for pre-paring photographlc silver halide emulsions having the required uniform particle size are disclosed in an article entitled "Ia:
Properties of Photographic Emulsion Grains", by Klein and Moisar, The Journal of PhotograPhic Science, Vol. 12, 1964, pp. 242-251; ;~-an article entitled "The Spectral Sensitization of Silver Bromide Emulsions on Different Crystallographic Faces", by Markocki, The Journal of Photographic Science, Vol. 13, 1965, pp. 85-89; an article entitled "Studies on Silver Bromide Sols, Part I. The ;~
Formation and Aging of Monodispersed Silver Bromide Sols", by Ottewill and Woodbridge, The Journal of Photographic Science, Vol.
13, 1965, pp. 98-103; and an article entitled "Studies on Silver ;~"
Bromide Sols, Part II. The Effect of Additives on the Sol Parti- ,.
. j. .
cles", by Ottewill and Woodbridge, The Journal of Photographic ~
Science~ Vol. 13, 1965~ pp. 104-107. . l~ -Where internal latent image sites have been formed through ~
,. :
internal chemical sensitization or the use of metal dopants, the surface of the silver halide grains can be below that which will produce substantial density in a surface developer--that is, ;
less than 0.4 when coated, exposed and surface developed as --19-- .;, '~'~.; "

3,~61363 described above. The silver halide grains are preferably pre-dominantly silver bromide grains chemically surface sensitized to a level which would provide a maximum density of at least 0.5 using undoped silver halide grains o~ the same size and halide -composition when coated, exposed and developed as described above. ~ -Surface chemical sensitization can be undertaken using ~ -techniques such as those disclosed by Sheppard, Waller et al, McVeigh or Dunn, cited above. The silver halide grains can also be surface sensitized with salts of the noble metals, such as ~ -ruthenium, palladium and platinum. Representative compounds are ammonium chloropalladate, potassium chloroplatinate and sodium chloropalladite, which are used for sensit~zing in amounts below that which produces any substantial fog inhibitlon, as described in Smith and Trivelli U.S. Patent 2,4LI8,060, issued August 31, 1948, and as antifoggants in higher amounts, as described in Trivelli and Smith U.S. Patents 2,566,245 issued August 28, 1951 and 2,566,263, issued August 28, 1951. The silver halide grains ~-can also be chemically sensitized with reducing agents, such as !~
stannous salts (Carroll U.S. Patent 2,487,850, issued November 15, 20 1949), polyamines, such as diethylene triamine (Lowe et al U.S.
Patent 2,518,698, issued August 15, 1950), polyamines, such as spermine (Lowe et al U.S. Patent 2,521,925, issued September 12, ,~
1950), or bis(~-aminoethyl)sulfide and its water-soluble salts (Lowe et al U.S. Patent 2,521,926, issued September 12, 1950). '~
The internal latent image silver halide grains can be optically sensitized using conventional techniques. For instance, spectral sensitization can be obtained by treating the silver "~
halide grains with a solution of a sensitizing dye in an organic solvent or the dye may be added in the ~orm of a dispersion as described in Owens et al British Patent 1,154,781 published June 11, 1969.

... .. .. _ .
~.

~6~363 Sensitlzing dyes useful in sensiti,zing silver halide emulsions are déscribed, ~or example, in Brooker et al U.S.
Patent 2,526,632, issued October 24, 1950; Sprague U.S. Patent 2,503,776, issued April 11, 1950; Brooker et al U.S. Patent 2,493,748, issued January 10, 1950; and Taber et al U.S.
! : ~
Patent 3,384,486, issued May 21, 1968. Spectral sensitizers which can be used include the cyanines, merocyanines, complex (tri- or tetranuclear) cyanines, holopolar cyanines, styryls, hemicyanines (e.g., enamine hemicyanines) oxonols and hemioxonols.
Preferred optical sensitizers ~nclude cyanine and merocyanine dyes, such as those described ,in U.S. Patents 1,846,301 and 1,846,302, both issued February~ 23, 1932, and ;
1,942,854, issued January 9, 1934, all by Brooker; 1,990,507 by White, issued February 12, 1935; 2,112,140, issued March 22, 1938; 2,165,338, issued July 11, 1939, 2,493,747, issued Janaury 10, 1950, and 2,739,964~ issued March 27, 1956, all by .
Brooker et al; 2,493,748 by Brooker et al, issued January 10, !'~, ' ~ " ' 1950; 2,503,776, cited above; and 2,519~001, issued August 15, . -1950, both by Sprague; 2,666,761 by Heseltine et al, issued January 19, 1954; 2,734,900, by ~eseltine, issued February 14, `
1956; an* 2,739,149 by Van Lare issued March 20, 1956; and Kodak Limited British Patent 450,958 accepted July 15, 1936.
To obtain the benefits of this invention, the internal latent image silver halide grains and an acylhydrazinophenyl-thiourea nucleating agent are brought together in a radiation-sensitive layer of a photographic element. In a preferred form of the invention, the silver halide grains and the acylhydrazino- Y
phenylthiourea nucleating agent are incorporated in a radiation-30 sensitive silver halide emulsion of a type employed in photo-graphy. Techniques for forming photographic silver halide .
::

. ' ~ 6i3~3 emulsions are generally well known to those skllled in the art. ~.:
Techniques for forming and washing silver ha].ide emulsions are ~-~
generally taught in Product Licensing Index, Vol. 92, December 1971, publication 9232, paragraphs I and II.
The photographic emulsions and elements described in .
the practice of this invention can contain various colloids alone ~ .
or in combination as vehicles, as binding agents and as various layers. Suitable hydrophilic materials include both naturally occurring substances such as proteins, for example, gelatin, 10 gelatin derivatives, cellulose derivatives, polysaccharides such . .
as dextran, gum arabic and the like; and~synthetic polymeric substances such as water-soluble polyvinyl;compounds like poly- 'r ' (~inylpyrrolidone), ac.rylamide polymers and~bhe like.
The descri.bed photographic emulsion layers and other .
layers of a photographic element employed in the practice of .
this invention can also contain, alone or in combination with `~`
hydrophilic, water-permeable colloids, other synthetic polymeric .. ~
compounds such as dispersed vinyl compounds such as in late~ .:
form and particularly those which increase the dimensional ~
stability of the photographic materials~ Suitable synthetic polymers include those described, for example, in U.S. Patents .
3,142,568 by Nottorf, issued July 28, 1964; 3,193,386 by White, issued July 6, 1965; 3,062,674 by Houck et al, issued November 6, 1962; 3,220,844 by Houck et al, issued November 30, 1965;
3,287,289 by Ream et al, issued November 22, 1966; and 3,411,911 by Dykstra, issued November 19, 1968; particularly effective are '`-those water-insoluble polymers or latex copolymers of alkyl acrylates and methacrylates, acrylic acid, sulfoalkyl acrylates or methacrylates, those which have cross-linking sites which facili- .
tate hardening or curing, those having recurring sulfobetaine units as described in Canadian Patent 774,054 by Dykstra, and -22- ~.

. ~
`'' ~13~;3 `~
those described in U.S. Patent 3,488,708 by Smith, issued ;
:~. ,. .: , January 6~ 1970. -The photographic emulsion layers can contain a variety of conventional photographic addenda. For example, hardeners of the ~ ;
the type disclosed in Product Licensing Index, cited above, para-graph VII, can be employed. Similarly plasticizers, lubricants and coating aids of the type disclosed in Product Licensing Index, cited above, paragraphs XI and XII, can be employed.
The acylhydrazinophenylthiourea nucleating agents of , ~, .. .
this invention can be employed in any desired concentration that will permit a degree of selectivity in developing image~
wise silver halide grains capable of formi~g an internal latent ~ .
image, which grains have not been imagewise exposed, as compared to silver halide grains containing an internal latent image formed by imagewise exposure.
In a preferred form of this invention the acylhydrazino-phenylthiourea nucleating agents are adsorbed to the surface of the internal latent image silver halide grains and employed in :
concentrations ranging from 0.1 to 200 mg of adsorbed nucleating agent per mole of silver. Preferably 0.5 to 25 mg of adsorbed nucleating agent per mole of silver is employed and, most ;`
preferably, 1 to 15 mg of adsorbed nucleating agent per mole of silver. Optimum concentrations can, of course, vary somewhat from one application to another. Where the acylhydrazinophenyl-thiourea nucleating agent is to be adsorbed to the surface of the silver halide grains, it can be adsorbed using the procedures well known to those skilled in the art for adsorbing sensitizing dyes, such as cyanine and merocyanine dyes, to the surface of silver halide grains.

-23- `

. .
^'.,: ' :, .

... ..

~Ci61363 It is spec~ically contemplated to employ ln combina-tion with acylhydrazinophenylthiourea nucleating agents other conventional nucleating agents. In a specifically preferred form one or a combin2tion of acylhydrazinophenylthiourea nucleating agents are employed at a concentration of up to about 200 m~ per mole of silver, as indicated above, in combin2tion with a conven-tional substituted hydrazine type nucleating agent wh~ch is present in a concentration o~ ~rom about 200 mg to about 2 gra~.s per mole o~ silver. Where the acylhydrazinophenylthiourea nucleating agent actually increases photographic speed, with increasing processing temperatures, uslng the nucleating agent in combination with a conventional nucleating agent w~.ich decreases photographic speed ~ith increasing processing temperatures, can result in a surprising degree o~ temperature insensitivity for the speed and develop-ability of the resulting photographic emulsion.
In one preferred form of this invention the acyl-hydraæinophenylthiourea nucleating a~ents are employed in combination with hydrazide and hydrazone nucleating agents of the type disclosed by Whitmore (~.S. Patent 3,227,552~, cited above. Such hydrazides and hydrazones are nitrogen-containing compounds having the formulas T-NH-NH-Tl and T-NH-N=T2 whereln T is an aryl radic~l and including substituted aryl radical, Tl is an acyl or a sulfonyl radical; and T2 ls an alkylidene radical and including substituted alkylidene radicals.
Typical alkyl radicals for the substituent T have the formula M-T3--wherein T3 is an aryl radical (such as phenyl, l-naphthyl, 2-naphthyl, etc.) and M can be such substituents ashydrogen, hydrGxy, amino, alkyl, alkylamino, arylamino, heterocyclic amino (amino containing a heterocyclic moiety), alkoxy, aryloxy, acyl-oxy, arylcarbonam.ido, alkylcarbonamido, heterocyclic carbonamido .
" ~ ' .~;

(carbonamido containing a heterocyclic moiety), arylsulfonamido, alkylsulfonamido, and heterocyclic sulfonamido ~sulfonamido containing a heterocyclic moiety). Typical acyl and sulfonyl radicals for ~he substituent Tl have the formula O O ,, Il 11 .'.
-S-Y or -C-G
O
wherein Y can be such substituents as alkyl, aryl and heterocyclic radicals. G can represent a hydrogen atom or the same substituents as Y as well as radicals having the formula O _ .
. .
-C-O-A
to form oxalyl radicals wherein A is an alkyi,' aryl or a hetero-cyclic radical. Typical alkylidene radicals for the substituent T2 have the formula =C-D2 wherein D can be a hydrogen atom or such radicals as alkyl, aryl and heterocyclic radicals. Typical aryl substituents for the above-described hydrazides and hydrazones include phenyl, naphthyl, diphenyl, and the like. Typical heterocyclic substituents for the above-described hydrazides and hydrazones include azoles, aæines, furan, thiophene, quinoline, `
pyrazole, and the like. Typical alkyl (or alkylene) substituents ;
for the above-described hydrazides and hydrazones have 1 to 22 ZO carbon atoms including methyl, ethyl, isopropyl, _-propyl, iso-butyl, n-butyl, t-butyl, amyl, _-octyl, _-decyl, _-dodecyl, n-octadecyl, n-eicosyl, _-docosyl, etc.
Illustrative specific hydrazide (named as hydrazine ;~
derivatives) and hydrazone nucleating agents useful in the :
practice of this invention include those set forth below in :. , Table II.
' ' ' ':

~L~6~363 ~;
;: ;'.
..
TABLE II
H~ acetyl-2-phenylhydrazlne H- 2 1-acetyl-2-(4-hydroxyphenyl)hydrazine H- 3 1-acetyl-2-(4~aminophenyl)hydrazine H- 4 1-acetyl-2-(4-methylphenyl)hydrazine H- 5 1-acetyl-2-(4-acetamidophenyl)hydrazine H- 6 1-acetyl-2-(4-benzamidophenyl)hydrazine H- 7 1-acetyl-2-~4-methoxyphenyl)hydrazine ~ ~
H- 8 1-acetyl-2-[4-(3-sulfobenzamido)phenyl]- ;
hydrazine H- 9 1-acetyl-2-(4-phenylsulfamidophenyl)- - ~:
hydrazine H-10 1-acetyl-2(4-methylsulf~namidophenyl)-hydrazlne ~~
H-ll l-phenylsulfonyl-2-phenylhydrazine H-12 1-methylsulfonyl-2-phenylhydrazine H-13 1-benzoyl-2-phenylhydrazine H-14 1-benzoyl-2-(4-benzamidophenyl)hydrazine H-15 1-ethoxalyl-2-phenylhydrazine H-16 1-methylsulfonyl-2-(3-phenylsulfonamido-phenyl) hydrazine .
H-17 1-(4-acetamidophenylsulfonyl)-2-(1-naphthyl)hydrazine H-18 1-ethylsulfonyl-2-(4-diethylaminophenyl)- .;
hydrazine H-l9 1-phenylsulfonyl-2-(4-benzamido-2,5- ~.
diethoxyphenyl)hydrazine H-20 5-(1-carbo-2-phenylhydrazino)-1-phenyl-3-pyrazolidone H-21 2-(1-carbo-2-phenylhydrazino)furan H-22 4-(1-carbo-2-phenylhydrazino)pyridine H-23 2-(1-carbo-2-phenylhydrazino)benzo-thiazole .~, H-24 1-[2-(2,4-di-tert-amylphenoxy)-5-(3,5-disulfobenzamido)benzoyl]-2-phenyl-hydrazine H-25 1-acetyl-2-~4-[5-amino-2-(2,4-di-te:rt-pentyl-phenoxy)benzamido]phenyl}hyd:razine ~
-26- ; .

: ~613~;3 ~
TABL~ II (Cont'd) H-26 1-lauroyl-2-phenylhydrazine H-27 1-lauroyl-2-~4-(3-sulfobenzamido)- :
phenyl]hydrazine H-28 1-methylsulfonyl-2-(4-octadecylphenyl)- `
hydrazine '~
H-29 1-octadecyloxalyl-2-phenylhydrazine ~ -H-30 1-octadecyloxalyl-2-[4-(3-sulfobenz- -amido)phenyl]hydrazine ..
H-31 1-lauroyl-2-[4-(~-methylsulfonamido-ethyl)phenyl]hydrazine H-32 1-~3-(2,4-di-tert-amyl-~-sulfophenoxy)- ~:
benzoyl]-2-phenylhydrazine ; :
H-33 5-~1-carbo-2-[4-(a-sulfostearamido)- .. : ~.
phenyl~hydrazino~-l-phenyl-3-pyrazolidone - .
H-34 Formaldehyde phenylhydra~qne ~5.
H-35 Formaldehyde 4-(~-methylsulfonamido-ethyl)phenylhydrazone , H-36 ~ucochloric acid 4-(~-methylsulfon-amidoethyl)phenylhydrazone H-37 Acetone 4-methylphenylhydrazone H-38 Benzaldehyde 4-(~-methylsulfonamido- ~.
ethyl)phenylhydrazone H-39 Benzaldehyde 4-methoxyphenylhydrazone : :
H-40 Benzaldehyde 4-(3-sulfobenzamido)phenyl-hydrazone H-41 Formaldehyde 4-methylsulfonamidophenyl- .-~
hydrazone H-42 Acetaldehyde 4-phenylsulfonamidophenyl- ,. .
hydrazone ,.
H-43 ~-tolualdehyde 4-diethylaminophenyl- ,~
hydrazone ~,:
H-44 cinchoninaldehyde 4-acetamidophenyl-hydrazone H-45 2-furaldehyde 4-methylsulfonamido-1- .~ i naphthylhydrazone H-46 Nicotinaldehyde 4-(3-methylsulfamyl- ;~
benzamido)-2,5-diethoxyphenylhydrazone H-47 Hendecanal 4-(a-sulfostearamido)phen hydrazone H-48 3-octadecyloxybenzaldehyde phenyl-hydrazone -27- .

,:. _ ., .
"

1~6~363 ~

.
TABLE II (Cont'd.) H-49 3-octadecyloxybenzaldehyde 4-(3-sulfo- .
benzamido)phenylhydrazone ~

H-50 benzaldehyde 4-[5-(3,5-disulfo)-2-(2,4- .
di-tert-pentyl-phenoxy)benzamido]phenyl-hydrazone dipotassium salt H 51 oxyguargum 4-(~-methylsul.fonamidoethyl)- ~-phenylhydrazone j H-52 1-phenylacetyl-2-phenylhydrazine H-53 1-formyl-2-~-tolylhydrazine In another preferred form of this invention the acyl- ~:~
hydrazinophenylthiourea nucleating agents.are employed in combina-tion with N-substituted cycloammonium quaternary salts of the `.
type disclosed by Kurtz, Harbison, Heseltine1and Lincoln, cited above. Generally these compounds can be represented by the formula:

N ~CH-CH). I-C-E

X (CH2)a ~.
E

wherein: -1) Z represents the atoms necessary to complete a heterocyclic nucleus containing a heterocyclic ring of 5 to 6 atoms in-cluding the quaternary nitrogen atom, with the additional atoms of said heterocyclic ring being selected from carbon, :.
nitrogen, oxygen, sulfur and selenium;
2) ~ represents a positive integer of from 1 to 2; ~;
3) a represents a positive integer of from 2 to 6; .'`~

4) xe represents an acid anion;

5) E represents a member selected from:
a) a formyl radical, ~;
b) a radical having the formula:

.'' ' ' .

: .

L 1 . ,.," ,, ~
-CH ..

wherein each of Ll and L2, when taken alone 3 repre- .
sents a member selected from an alkoxy radical and an -alkylthio radical, and Ll and L2, when taken together, represent the atoms necessary to complete a cyclic .
radical selected from cyclic oxyacetals and cyclic thio-acetals having from 5 to 6 atoms in the heterocyclic acetal ring, and ~ .
c) a l-hydrazonoalkyl radical; a~d -

6) E1 represents either a hydrogen atom,;an alkyl radical, an `
aralkyl radical, an alkylthio radical ~ an aryl radical .
such as phenyl and naphthyl, and including substituted aryl .
radicals.
In certain preferred embodiments of this invention, the N-substituted, cycloammonium quaternary salts are those which ..
convain N-substituted alkyl radicals having the terminal carbon atom substituted with a hydrazono radical, an acyl radical such as a formyl radical, an acetyl radical or a benzoyl radical, and those which have a dihydro--aromatic ring nucleus such as, ;:~
for example, a dihydropyridinium nucleus.
Illustrative specific N-substituted quaternary ammonium salt nucleating agents useful in the practice of this invention :1 include those set forth below in Table III. ~ -TABLE III .

QAS- 1 3-(2-formylethyl)-2-methylbenzothia-zolium salt QAS- 2 3-(2-formylethyl)-2-methylnaphtho-[2,3-d]thiazolium salt .

QAS- 3 3-(2-acetylethyl)-2-phenoxymethyl- ..
benzothiazolium salt ;`

QAS- 4 3-(2-acetylethyl)-2-benzylbenezo-selenazolium salt ~61363 ;
.
TABLE III (Cont'd) QAS-5 1,2-dihydro-3-methyl-4-phenylpyrido-[2,1-b~benzothiazolium salt QAS- 6 1,2-dihydro-3-methyl-4-phenylpyrido- l ~2,1-b]-5-phenylbenzoxazolium salt 1.
QAS- 7 1,2-dihydro-3,4-dimethylpyridoC2,1-b]-benzothiazolium salt ;~
QAS- 8 1,2-dihydro-3,4-diphenylpyrido[2,1-b]-. benzoxazolium salt j :
QAS- 9 1,2-dihydro-2-butyl-3-methyl-4-phenyl-pyrido~2,1-b~-5-carbethoxybenzothia- j zolium salt I `~ :
QAS-10 1,2-dihydro-3-methyl-4-phenylpyrido- .
[2,1-b]-5-(N-methyl-~-phenylcarbamido)- ~ ~:
benzothiazolium salt ~ .:
. : .
QAS-ll 1,2-dihydro-3,4-dimethylpyrido[2,1-b~-5-(N-ethyl-N-octadecylcar,bamido)benzo- ` ;~
thiaæolium salt .
QAS-12 3-(3,3-diethoxypropyl)-2-methylbenzo- ~
thiazolium iodide .
QAS-13 1-(2-formylethyl)lepidinium bromide ..
QAS-14 3-[3,3 di(ethylthio~propyl]-2-methyl- . -benzothiazolium iodide .
'~:
QAS-15 3-(6,6-diethoxy-n-hexyl)~2-methylnaphtho- :~
[2,1-d]thiazolium bromide ~.
QAS-16 3-[2-(1,3-dioxan-2-yl)ethyl~-2-methyl- .:
benzoselenazolium bromide .
QAS-17 3-[3-(1,3-dioxolan-2-yl)propyl]-2-phenyl- .
benzimidazollum perchlorate ::
,....
QAS-18 5-chloro-3-(2-formylethyl)-2-methylbenzo- ..
thiazolium bromide : :
QAS-l9 3-r3~3-di(ethylthio)propyl]-2-methyl- :~
benzothiazolium iodide j QAS-20 3-(6,6-diethoxy-n-hexyl)-2-methyl- ~::
naphtho~2,1-d]thiazolium bromide :~
QAS-21 3-~2(1,3-dithiolan-2-yl)ethyl]-2-methyl-benzothiazolium iodide :~
QAS-22 3-(3,3-diethoxypropyl)-2-ethylthio- ~:
. naphtho~2,3-d~thiazolium methylsulfate l~

QAS-23 3-[3-(1,3-dioxolan-2-yl)propyl]-1-ethyl- l~-2-phenyl-benzimidazolium perchlorate -30~

r,, .. ,.~, .

' ~Q61363 To form a photographic element according'to the present invention it is merely necessary to coat onto a conventional photographic support a radiation-sensitive composition comprised of internal latent image silver halide `' grains and an acylhydrazinophenylthiourea nucleating agent.
Conventional photographic supports~ including film and paper photographic supports, are disclosed in Product Licensing .: .
Index, cited above, paragraph X. " ' A simple exposure and development-process can be ' ~ -10 used to form a direct-positive image. In one embodi- '~
ment, a photographic element comprising at least one layer ' of a silver halide composition as described above can be ~' imagewise exposed and then developed in a sil'ver halide surface developer.
It is understood that the term "surface developer" ' `
encompasses those developers which will reveal the surface '' latent image on a silver halide grain, but will not reveal ''~ ' substantial internal latent image in an internal image-forming `- '`
emulsion, and under the conditions generally used develop a surface-sensitive silver halide emulsion. The surface developers can generally utilize any of the silver halide developin'g agents or reducing agents, but the developing `
bath or composition is generally substantially free of a silver halide solvent (such as water-soluble thiocyanates, ~' water-soluble thioethers, thiosulfates, ammonia and the ' like) which will crack or dissolve the grain to reveal substantial internal image. Low amounts of excess halide are sometimes desirable in the developer or incorporated in the emulsion as halide-releasing compounds, but high amounts of iodide or iodide-releasing compounds are generally avoided to prevent substantial cracking of the grain.

,... .

'' ' ;. ' ~6~363 Typical silver halide developing agent~ whlch can be used in the developing composltions of thls lnventlon include hydroqulnones, catechols, aminophenols a 3-pyrazolidones, ascorbic `~
acid and its derlvatives, reductones, phenylenediamines and the like or combinations thereof. The developing agents can be lncorporated in the photographic elements wherein they are brought ln contact with the silver halide a~ter imagewise exposure, how~
ever, in certain embodiments they are preferably employed in the developlng bath.

~ .:
The developing compositions used ln the procesæ o~ -this invention can also contaln certain antifoggants and develop-ment restrainers, or optionally they can be~ncorporated in I ;
layers of the photographic element. For example, ln some applica-tions improved results can be obtained when the direct-positive emulsions are processed in the presence Or certain antifoggants as disclosed in U.S. Patent 2,497,917~
, Typical useful antifoggants include benzotriazoles~
such as benzotriazole, 5-methylbenzotriazole, 5-ethyl-benzotriazole and the like, benzimidazoles such as 5-nitro- ..
benzimidazole, and the like, benzothiazoles such as 5-nitro-benzothiazole, 5-methylbenzothiazole and the like, heterocyclic thiones such as l-methyl-2-tetrazoline-5-thione and the like, triazines such as 2,4-dimethylamino-6-chloro-5-triazine and the like, benzoxazoles such as ethylbenzoxazole and the like, and :.
pyrroles such as 2,5-dimethylpyrrole and the like.

, .

.

~''~: ' . ~:

':

In certaln embodiments, good results are obtained when the ~
': .
elements are processed ln the presence of high levels of the anti-foggants mentioned above. When antifoggants such as benzotriazoles are used, good results can be obtained when the processing solution contains up to 5 g/l and preferably 1 to 3 g/l; when they are incor-porated in the photographic element, concent:rations of up to 1000 mg/mole of Ag and preferably concentrations of 100 to 500 mg/mole of Ag are employed. ,-;
. , .
It is, of course, known in the art that nucleating agents 10 can be incorporated into surface developers in forming direct- ; -positive images. While the acylhydrazinophenylthiourea nucleating agents could conceivably be incorporated into surface developers, it is our view that superior results are optainable by incorporat-ing the acylhydrazinophenylthiourea nucleati~g agents in the photo-graphic element prior to development. It is, however, recognized that the other conventlonal nucleating agents discussed above for use in combination with the acylhydrazinophenylthiourea nucleating agents could be incorporated in the surface developer, wholly or -~
partially, rather than being incorporated in the photographic ele-ment. It is preferred that the nucleating agents be entirely in-corporated in the photographic element as opposed to the surface developer in most applications.
This invention may be used with elements designed for color photography, for example, elements containing color-forming couplers such as those described in U.S. Patents 2,376~679 by :;
Frohlich et al, 2,322,027 by Jelley et al, 2,801,171 by Fierke et al, 2,698,794 by Godowsky, 3,227,554 by Barr et al and 3,046,129 by Graham et al; or elements to be developed in solutions containing color-forming couplers such as those described in U.S. Patents 30 2,252,718 by Mannes et al, 2,592,243 by Carroll et al and 2,950,970 by Schwan et al; and in false-sensitized color materials such as those described in U.S. Patent 2,763,549 by Hanson.

'.'~ "' This invention ls useful with photographic elements used in image trans~er processes or in imag~ transrer film units.
Generally the invention can be used with the color image trans-rer processes and the film units as described in Whitmore U.S.
Patents 3,227,1550 and 3,227,552, issued January 4, 1966; U.S. ~;
Patent 2,983,606; U.s. Patent 2,543,181; Whitmore Canadian Patent 674,082; Belgian Patent 757,959 and 757,960, both issued April 23, 1971, and the like.
The silver halide emulsions as described herein are particularly use~ul in combination with negative working image dye providing materials; i.e., those materials which produce a negative pattern of trans~erred image dye when used in combina-tion with a negative-working silver halide emulsion. Typical useful negative-working image dye providing materials are dis-closed in Fleckensteln Belgian Patent 788,268, issued `
February 28, 1973; U.S. Patent 3,698,897, issued October 17, 1972, of Gompf and Lum; U.S. Patent 3,728,113, issued April 17, 1973, of Becker et al; U.S. Patent 3,725,062, issued April 3, 1973, of Anderson and Lum, U.S. Patent 3,148,062, issued September 8, 1964, of Whitmore et al; U.S. Patents 3,628,952 and 3,844,785;
and German OLS 2,317,134.
The direct positive silver halide emulsions o~ thisinventlon are pre~erably used in combination with negative-working dye providing materials because the combination pro-duces a positive trans~er image. However, it is recognized that the direct positive emulsions can also be used with positive-working image dye providing materials such as dye developers as ;' ~
disclosed in U.S. Patent 2,983,606, oxichromic developers as dis- , ;
closed in U.S. Patent 3,880,658, shi~ted dye developers as dis-closed in Hinshaw Belgian Patent 810,195, issued July 25, 1974, .
and the like. Positive images are obtained in the exposed silver `~ ' .; , -34~

,' ~.

; 1~6~L363 halide emulsion layers while a trans~erred ne&ative image is obtained where the direct positive emulsions are used in combina- :
tion with negative-working image dye providing materials. Also, where the exposure is made of a negative image or through a nega- ~-tive image record, positive transfer images are obtained with the combination Or direct positive emulsions and positive-working :
image dye providing materials.
Generallyl the image-trans~er rilm units in accordance ^ :
with this invention comprise:
1) a photosensitive element comprising a support having thereon at least one layer containin~ a radiation-sensitive .
internal latent image silver halide and an acylhydrazino~
phenylthiourea nucleating agent as described above, preferably having associated therewith an image dye-providing material; ~.
2) an image-receiving layer which can be located on a separate support and superposed or adapted to be superposed on said photosensitive element, or prererably can be coated as a ;~.
layer in the photosensitive element, and :
3) means containing an alkaline processing composition adapted to discharge its contents within said rilm unit and wherein .
said film unit contains a silver halide developing agent so ,`;
that the processing composition and developing agent when .
brought together ~orm a silver halide surrace developer. ~ .
` ' --35- : .

In highly preferred embodiments, the film units of this invention contain a support having thereon a layer contain-ing a blue-sensitive emulsion having associated therewith a yellow image dye~providing material, a red-sensitive sllver halide emul-sion having associated therewith a cyan image dye-providing material, and a green-sensitive emulsion having associated there-with a magenta image dye-providing material, and preferabl~ all of said image dye-providing materials are initially immobile image dye-providing materials.
The terms "diffusible" (or "mo~ile") and "immobile" (or "nondiffusible") as used herein refer to co~pounds which are lncor-porated in the photographic element and, upoh'contact with an alkaline processing solution, are substantially diffusible or substantially immobile, respectively, in the hydrophilic colloid layers of a photographic element. ~ ~
The term "image dye-providing material" as used herein ` -is understood to refer to those compounds which are employed ;~
to form dye images in photographic elements. These compounds j ;
include dye developers, shifted dyes, color couplers, oxichromic compounds, dye redox releasers, etc.
In one preferred embodiment, the silver halide ?,, emulsions of the invention are used in association with immobile redox dye-releaser image dye-providing compounds. The immobile redox dye-releasers undergo oxidation followed, in certain ~ ~ -instances, by hydrolysis to provide an imagewise distribution of a mobile image dye. Compounds of this type can be used with direct-positive emulsions to ~orm negative image records ~ ;~
in the exposed photographic element and will provide . . ..
`'' ' ... . .

..~

~i1363 ~
a positive image in diffusible dye for transfer to an image-receiving layer, such as an image-transfer film unit. Typi-cal useful compounds of this type are disclosed in Whitm~re et al Canadian Patent 602,607, issued August 2, 196~;
Fleckenstein et al U.S. Patent 3,928,312, issued December 23, 1975; and U.S. Patents 3,698,897, 3,728,113, 3,725,062, 3,227,552, 3,443,939, 3,443,940 and 3,4~3,941, and the like. Where the receiver layer is coated on the same support with the photosensitive silver halide layers, the support is preferably a transparent support, an opa~ue layer is preferably positioned between the image-receiving layer and the photo-sensitive silver halide layer, and the alkaline processing ' composition preferably contains an opacifying substance such as carbon or a pH-indicator dye which is discharged into the ;
film unit between a dimensionally stable support or cover sheet and the photosensitive element.
In certain embodiments, the cover sheet can be super- `~
posed or is adapted to be superposed on the photosensitive ~;
element. The image-receiving layer can be located on the cover sheet so that it becomes an image-receiving element. In certain preferred embodiments where the image-receiving layer is located in the photosensitive element, a neutralizing layer is located on the cover sheet.
A means for containing the alkaline processing solution can be any means known in the art for this purpose, including rupturable containers positioned atthe poin-t of desired discharge of its contents into the film unit and adapted to be passed be-tween a pair of juxtaposed rollers to effect discharge of the contents into the film unit, frangible containers positioned over or within the photosensitive element, hypodermic syringes, and the like. -'~- .:, ':

' ' ' ~ '' . , ~ ' ~&J1363 , . ' It is known in the art that neutralizing layers contain-ing acidic materials, such as polymeric acids, rnonomeric acids, hydrolyzable materials and the like, can be positioned within an image-transfer film unit to effect shutdown of development of silver halide and transfer of the image dye-providing substance.
Neutralizing layers can also be used in the film units of the present invention, including acid layers positioned behind timing layers to delay neutralization of the element, acid layers -positioned near the image-receiving layer, acid layers on a ~
10 cover sheet used to distribute the processing composition ~`
uniformly over the photosensitive elemerrt, acid layers within i~

the photosensitive element, and the like. ;

The photographic etnulsions and eIe~nents o~ this inven-tion are described by the generic designation direct-positive.
The term "direct-reversal" has recently been ernployed in the art to distinguish direct-positive emulsions and elements which con-tain unfogged silver halide grains and nucleating agents from direct-positive silver halide emulsions and elements containing ~i surface fogged silver halide grains. It is to be understood that .~.,~; , ..: . .
this invention is directed to direct-reversal photographic ~-emulsions and elements.

The invention can be ~urther illustrated by the follow-ing examples.
.. , .. ---,- -- - - - - , ~ :

,;; :. :
. .

. .`
.. . . . .
. ,.:
'`', ..' _38-'; ' ,' .

. . - _~ . .
~, . .... . . .

~96~L363 EXAMPLES
';
ormyl-2-(4-nitrophenyl)hydrazine 4-Nltrophenylhydrazine (~.2 g, o.o6 mole), sodium formate (4.o8 g, 0.06 mole), and ethyl formate (148 g, 2.00 moles) were mixed in ethanol (40 ml) and formic acid (30 ml). The mix-- ture was heated on a steam bath; the volume of the mixture was ;
reduced to approximately 100 ml by continued boiling. The hydra-zide product crystallized out of the concentrated reaction mix-ture upon cooling. The product was filtered off, washed with ethanol, and dried. Yield 10.2 g (94%), m.p. 183-185C.
2. 1-Benzoyl-2-(4-nitrophenyl)h~drazine ~
. j .:
4-Nltrophenylhydrazine (15.0 g, 0.10 mole) and benzoic anhydride (22.6 g, 0.10 mole) were mixed in benzene (100 ml) and the mixture was refluxed for 2 hours. The reaction mixture was chilled in ice and then filtered. The solid was washed with ethanol and allowed to dry. The material was recrystallized from ethanol. Yield 20.5 g (ôO%), m.p. 194-195~C.

'.

.... . . . . ... .. ~ ~ _ 13~3 ~`

3. 1-Formyl-2-(4-aminophenyl)hydrazine l-Formyl-2-(4-nitrophenyl)hydrazine (10.2 g, 0.056 mole) and 10% palladium/charcoal ~catalytic amount) were suspended in ethanol (500 ml) in a Parr shaker bottle. The reaction ;
mixture was hydrogenated at room temperature until hydrogen uptake ceased. The reaction mixture was filtered and the solvent was evaporated from the filtrate leaving a white crystalline powder.
. Yield 7.1 g (84%), m.p. 122-125C.
4. 1-Benzoyl-2-(4-aminophenyl)hydrazine 1-Benzoyl-2-(4-nitrophenyl)hydrazine (14.3 g, o.o56 ~!~
mole) and 10% palladium/charcoal (catalytic amount) were suspended in ethanol (300 ml) in a Parr shaker bottle. The reaction '~
mixture was hydrogenated at room temperatureJuntil hydrogen uptake ¦~
ceased. The reaction mixture was filtered and the solvent was evaporated from the filtrate leaving a tan crystalline powder.
Yield 11.5 g (90%), m.p. 134-136C. I
5. 1-Acetyl-2-(4-benzalaminophenyl)hydrazine i ~;
l-Acetyl-2-(4-aminophenyl)hydrazine (8.25 g~ 0.05 mole) and benzaldehyde (5.3 g, 0.05 mole) were mixed in ethanol 20 (50 ml). The mixture was stirred thoroughly and was warmed to ¦~
approximately 75C for one-half hour. The addition product precipitated out of the reaction mixture. The mixture was chilled in ice and then riltered. The solid was washed with ether and ~ :
dried. The product was a white crystalline powder. Yield 12.0 g ' ;
(94%), m.p. 172-174C. ~' 6. 1-Acetyl-2-(4-benzylaminophenyl)hydrazine l-Acetyl-2-(4-benzalaminophenyl)hydrazine (5.1 g, ~ -0.02 mole) and platinum oxide (catalytic amount) were suspended ~... .
in ethanol (200 ml) in a Parr shaker bottle. The reaction mixture was hydrogenated at room temperature until hydrogen uptake ceased. The reaction mixture was filtered and the solvent :,, .:, . .
-40- /~

~... . .
,:

~6~3~3 was evaporated from the filtrate leaving a white crystalline 5 powder. Yield 4.7 g (92%), m.p. 118-120C.

7. 1-Acetyl-2-[4-(4-methoxybenzyl)aminophenyl~hydrazine Procedures (5.) and (6.) above were repeated, but with 4-methoxybenzaldehyde substituted for benzaldehyde.

8. 1,3-Bis[4-(2-formylhydrazino)phenyl]thiourea (NA-l) O S O
HC-NH-NH-P~ NH-C-NH-~ -NH-NH-CH ~ ~

C15Hl6N602S .:
~.
Sodium carbonate (2.1 g, 0.02 mole) was dissolved in water (100 ml). Bis(carboxymethyl)trithioc~a~bonate (4.5 g, 0.02 10 mole) was added portionwise with vigorous stirring. The pH of the reaction mixture was ad~usted to 9.5 by the addition of sodium carbonate. The mixture was then heated to approximately 95C. l-Formyl-2-(4-aminophenyl)hydrazine (6.5 g, 0.043 ~`
mole) was added in one po.rtion to the reaction mixture. Stirring was continued for five minutes. The reaction mixture was chilled, -the solid was filtered off, washed thoroughly with water and dried.
Yield 4.5 g (66%), m.p. 212-214C.

9. 1,3-Bis[4-(2-acetylhydrazino)phenyl]thiourea (NA-2) `~ r O S O ','.' ~ -H3C-C-NH-NH~ -NH-C-NH-~ -NH-NH-C-CH3 i C17H20N602S
~, j 20 Sodium carbonate (100 g, o.96 mole) was.dissolved in water (1 liter). Bis(carboxymethyl)trithiocarbonate (55 g, 0.24 ~.
mole) was added portionwise with stirring. The solution was ~
, heated to 90C and l-acetyl-2-(4-aminophenyl)hydrazine (78 g, ~;
0.47 mole) was added in one portion. After stirring at 90C
for 30 min., the product was filtered of r, washed thoroughly with water and dried. Yield 50 g (56%), m.p. 234-236C.

'~

~61363

10. 1~3-Bis[4-(2-benzoylhydrazino)phenyl]thiourea (NA-6) S O '~
C6Hs-C-NH-NH-~ -NH-C-NH-~ -NH-NH-C-C~Hs C27H2~N602S

Sodium carbonate (4.65 g, 0.044 mole) was dissolved in ...
- a solvent mixture of water (95 ml) and ethanol (30 ml). Bis- ; ;~
(carboxymethyl)trithiocarbonate (2.5 g, 0.011 mole) was added portionwise. Vigoroufi stirring o~ the reaction mixture was main- ~`
tained until all solid was dissolved. It was then heated to 80-85C and l-benzoyl-2-(4-aminophenyl)hydrazine (5.0 g, 0.022 mole) was added in one portion. ' , ;
Stlrring and heating were maintained for one and one-half hour and the reaction mixture was then chilled. The solid was removed by filtration, washed and dried. Yield 2.05 g (37%), m.p. 185-187C.

11. 1-[4-(2-Formylhydrazino)phenyl]-3-methylthiourea (NA~

O S ',;' H-C-NH-NH-~ H-C-NH-CH3 \ ~ = ~ ... . . .
C~Hl2N40S

l-Formyl-2-(4-aminophenyl)hydrazine (1.51 g, 0.01 mole) and methyl isothiocyanate (0.73 g, 0.01 mole) were mixed ;;
in ethanol (20 ml) and the mixture was refluxed for 30 minutes.
The mixture was chilled in ice, and water was added to precipi- -tate the product. The product came out of solution in an oily form, but solidifed upon scratching and standing. The solid material was filtered off and washed thoroughly with ether. i~
The product was dried to give a white crystalline powder. ;
Yield 1.3 g (58%), m.p. 176-178 C.

,. ~ "
~,, ' .

~6~363

12. 3-Butyl-1-[4-(2-~ormylhydrazino)phenyl]~hiourea (NA-l?) O S '~
H-C-NHNH-~ -NH-C-NH-(CH2)3CH3 C12H.~N40S
l-Formyl-2-(4-aminophenyl)hydrazine (7.5 g, 0.05 mole) and butyl isothiocyanate (5.7 g, 0.05 mole) were mixed in ethanol (120 ml) and the mixture was refluxed for 30 minutes. The resulting solution was chilled in ice and upon scratching the product crystallized out as a white solid.
~he mixture was filtered and the solid was washed with ether. The product was dried to give a pale tan crystalline 10 powder. Yield 9.8 g (71l%), m.p. 129-131C. ,~

13. 1-[4-(2-Acetylhydrazino)phenyl]-3-ethylthiourea (NA-13) O S '.'.'' ' ~ ' H3C-C~NH-NH-~ -NH-C-NH-CH2CH3 l-Acetyl-2-(4-aminophenyl)hydrazine (1.65 g, 0.01 mole) and ethyl isothiocyanate (0.~7 g, 0.01 mole) were reacted according to procedure (11.). Yield 1.7 g (67%), p.m. 191-193C.

14. 3-Cyclohexyl-1-[4-(2-formylhydrazino)phenyl]- ;
thiourea (NA-14) __ ~

. A
H-C-NHNH--~ ~-NH-C-NH-~\ S /- -~

C14HzoN40S
Procedure (12.) was employed with 1-formyl-2-(4-aminophenyl)hydrazine (7.5 g, 0.05 mole) and cyclohexyl iso-thiocyanate (7.1 g, 0.05 mole). Yield 9.6 g (66%), m.p.
158-160C. ;~

:~6~363 ,,.; :.

15. 1-[4-(2-Formylhydrazino)phenyl]-3-phenyithiourea (NA-16) ;
,': :
S ' :.~ ::
Il o--~
H~C-NH-NH-~ -NH-C-NH-C 6 H5 ~'~' " ' '' C14H1~N~OS i . ` ' ':
l-Formyl-2-(4-aminophenyl)hydrazine (30 g, 0.20 - mole) was dissolved in acetonitrile (550 ml) with heat. Phenyl "10 isothiocyanate (28 g, 0.22 mole) was added in one portion. The :. ..
mixture was refluxed for 5 minutes and then chilled. The solid ~ ':
was filtered off, washed with acetonitrile and dried at 75C. ,-Yield 52 g (91%), m.p. 188-188.5C.

16. 1-[4-(2-Acetylhydrazino)phenyl] 3-phenylthiourea (NA-17) O S : , HsC-C-NH-NH-~NH-C-NH-C6H5 `;
9=0 .': ' l-Acetyl-2-(4-amlnophenyl)hydrazine (8.25 g, 0.05 mole) and phenyl isothiocyanate (6.8 g, 0.05 mole) were suspended in acetonitrile (100 ml). The resulting mixture was heated at ~ -reflux with stirring for 5 minutes. The product separated from solution as a white solid. After chilling, the product was removed from the reaction mixture by filtration and washed thoroughly with ether. Yield 14.5 g (96%), m.p. 205-207C.

~ .
. , .

17. 1-[4-(?~ enzoylhydrazino)phenyl]-3-phenylthiourea-(NA-l5) O S
C6H5-C-NH-NH-~-NH-C-NH-C6H5 C20H18N~OS

;

~ ' '" ~ . , ~6~363 l-Benzoyl-2-(4-aminophenyl)hydrazine (1.14 g, 0.005 mole) and phenyl isothiocyanate (2.7 g, 0.02 mole) ~ere mixed ~`
together and heated until contents became fluid. Gentle warming was continued for a few minutes and the reaction mix-ture was then chilled and diluted with ether. After some , stirring and scratching, the product precipitated from solu-tion. It was filtered off, washed thoroughly with ether and dried. Yield 1.7 g (94%), m.p. 149-151C.

18. 3-Benzyl-1-[4-(2-formylhydrazino)phenyl]thiourea (NA-l9) 0 5 ;
H-C-NHNH-~ NH-C-NH-C~2-~

Cls~l;sN~OS
l-Formyl-2-(4-aminophenyl)hydrazine (1.51 g, 0.01 mole) and benzyl isothiocyanate (1.49 g, p.01 mole) were '-mixed in ethanol (30 ml) and the mixture was refluxed for 20 minutes. The product separated from solution as a white ~;
solid. The reaction mixture was chilled in ice and the !;
solid was collected by filtration. The product was washed thoroughly with ether and then was dried. Yield 2.5 g (83%), m.p. 152-154C.

19. 1-[4-(2-Formylhydrazino)phenyl]-3-heptylthiourea (NA-20) O S
H-C-NHNH-~ ~C-NH-c-NH-(cH2)6cH3 ClsH24N4CS S
Procedure (12) was employed with 1-formyl-2-(4-aminophenyl)hydrazine (1.51 g, 0.01 mole) and heptyl iso-thiocyanate (1.57 g, 0.01 mole). The product was recrystal-lized from ethanol. Yield 1.5 g (49%), m.p. 148-150C.

20. 1-[4-(2-~ormylhydrazino)phenyl]-3-decylthiourea (NA-?l) ,~

`' .

L3~3 ~ ,.. .. ~, .
S ,. ,,.: .:
H-C-NHNH-~-NH-C-NH-(CH2)~CH3 Cl~H30N40S
Procedure (12.) was employed with 1-formyl-2-(4-aminophenyl)hydrazine (1.51 g, 0.01 mole) ancL decyl isothio- ~-cyanate (1.99 g, 0.01 mole). Yield 2.4 g (69%), m.p. 150-152C. ';~

21. 3-(4-Cyanophenyl)-1-[4-(2-formylhydrazino)-phenyl]thiourea (NA-22) '. ' .
.. ' O S ','~: ' H-C-NHNH-o~ ~-NH-C-NH-~ CN
C15Hl3N50S `
Procedure (18.) was employed with 1-formyl-2-(4-aminophenyl)hydrazine (1.5 g, 0.01 mole) and 4-cyanophenyl isothiocyanate (1.6 g, 0.01 mole). Yield 2.`2'g (71%), m.p.
180-182C. ~`

22. 1-[4-(2-Formylhydrazino)phenyl]-3-(4-methoxy-phenyl)thiourea (NA-23) O S .~ .,.. ,.' H-C-NHNH-~ -NH-C-NH-~ -OCH3 C15Hl~N40~S
Procedure (18.) was employed with 1-formul-2-(4- , . .:
aminophenyl)hydrazine (1.51 g, 0.01 mole) and 4-methoxyphenyl ,~
isothiocyanate (1.65 g, 0.01 mole). Yield 1.7 g (53%), m.p.
198-200C.

23. 1-Formyl-2-(4-nitro-2-methoxyphenyl)hydrazine 2-Methoxy-4-nitrophenylhydrazine (11.0 g, o.o6 mole; prepared by reduction of the diazonium salt from 2-methoxy-4-nitroaniline), sodium formate (4.1 g~ 0.06 mole) and ethyl formate (148 g, 2.00 moles) were mixed in ethanol ~ (40 ml) and formic acid (30 ml). The mixture was heated on 'j a steam bath; -the volume of the mixture was reduced to i, approximately 100 ml by continued boiling. The hydrazide produce crystallized out of the concentrated reaction mix-. '; ' .::
. . .

. _ . .

- ~06~363 ~ , ....
ture upon cooling. The product was filtered off, washed with ethanol, and dried. Yield 8.5 g (66%), m.p. 189-191C.

24. 1-Fo'rmyl-2-(4-amino-2-methoxyphenyl)hydrazine Procedure (3.) was employed with 1-formyl-2-(4-nitro-2-methoxyphenyl)hydrazine (4.0 g, 0.019 mole). Yield 2.5 g (74%), m.p. 113-116C.

25. 1-t4-(2-Formylhydrazino)-3-methoxyphenyl]-3-phenylthiourea (NA-24)_ .
o OCH3 S ~, H-C-NHNH--4 ~--NH-C-NH--4 ~9 Cl5Hl6N402S ,~
Procedure (18.) was employed with'l'-formyl-2-(4-amino-2-methoxyphenyl)hydrazine (1.0 g, 0.0056 mole) and phenyl isothiocyanate (0.'75 g, 0-00S6 mole). Yield 0.90 g (51%), m.p. 183-184C.

26. 3-Butyl-1-[4-(2-formylhydrazino)-3-methoxy-phenyl]thiourea (NA-25) o OCH3 S
H-C-NHNH--4 ~--NH-C-NH-(CH2)3CH3 C13HzoN~OæS
Procedure (12.) was employed with 1-formyl-2-(4-amino-2-methoxyphenyl)hydrazine (1.2 g, o.oo66 mole) and butyl isothiocyanate (0.76 g, 0.006 mole). Yield 0.90 g (46~), m.p. 130-132C. -

27. 3-Cyclohexyl-1-[4-(2-formylhydrazino)-3-methoxy-phenyl]thiourea (NA-26) o OCH3 S
H-C-NHNH--4 ~-NH-C-NH--~ S

o=~ ,,_. , Cl5H22N~02S ;`

. ,, 363 ~ ~

Procedure (11.) was employed with 1-formyl-2-(4 amino-2-methoxyphenyl)hydrazine (1.2 g, o.oo66 mole) and ',' cyclohexyl isothiocyanate (0.93 g, o.oo66 mole). Yield 0.50 g (24%), m.p. 131-133C. ~

28. 1-[4-(2-~ormylhydrazino)-3-methoxyphenyl]-3-(4- ',, methoxyphenyl)thiourea (NA-27) H-C-NHNH-o~ ~-NH-C-NH-~ -OCH3 ~;

C16H1~N~03S ~ .
Procedure (18.) was employed with 1-formyl-2-(4-amino~2-methoxyphenyl)hydrazine (1.2g, o.oo6 mole) and l~
10 methoxyphenyl isothiocyanate (1.1 g, 0.0066,m,ole). Yield ~ ' ''' 1.6 g (70%), m.p. 160-162C. ''''

29. 2-(4-Nitrophenyl)-l-trifluoracetylhydrazine '~ ;
4-Nitrophenylhydrazine (7.6 g, O.OS mole) was ' mixed with benzene (150 ml) and the resulting mixture was ^
stirred under nitrogen at room temperature. A solution of ''' trifluoroacetic anhydride (10.5 g, 0.05 mole) in benzene (50 ml) was added dropwise. The mixture was stirred vigor- ~
ously as a thick yellow solid precipitated out. After the ,', addition was complete~ the mixture was stirred for one more,, ' , 20 hour at room temperature. The mixture was filtered and the `
solid was washed with benzene and then allowed to dry. Yield 12.2 g (97%), m.p. 115-117C. , ,

30. 2-(4-Aminophenyl)-l-trifluoroacetylhydrazine 2-(4-Nitrophenyl)-l-trifluoroacetylhydrazine (2.5 g, 0.01 mole) and platinum oxide (84%, catalytic amount) were mixed in ethanol (100 ml) and ethyl acetate (100 ml) in a ' Parr shaker bottle. The reaction mixture was hydrogenated at room temperature until hydrogen uptake ceased. The re-action mixture was filtered and the solvent was evaporated _48-. .
~.
--- . .

~06~363 from the filtrate leaving a brown semisolid., yield 2.0 g (91%), no m.p. was taken on this material. Spectral data ~.

verified its structure.

31. 3-Phenyl-1-[4-(2-trifluoroacetylhydrazino)-phenyl]thiourea (NA-28) S O
G~ ~ O - N H- C- N H - D~ ~o - N H N H - C-- C F 3 C1sH13F3N40S
2-(4-Aminophenyl)-l-trifluoroacetylhydrazine (2.0 g, 0.0091 mole) and phenyl isothiocyanate (1.2 g, 0.0091 mole) .
. . .^~ . ~ .
were mixed together in ethanol (25 ml) and the mixture was ' heated to reflux for 20 minutes. A white iolid precipitated out of the mixture during the heating. The~mlxture was chilled in ice and the solid was filtered off, washed with ethanol, and dried. Spectral data on this material indicated that it was not the desired product. The filtrate from above was diluted with water and a second solid material formed.
This material was filtered off, washed with water and dried to give a white crystalline powder. Yield 0.80 g (25%), m.p.
172-174C. Spectral evidence verified that this substance was the desired product.

32. 1-(4-Chlorobenzoyl)-2-(4-nitrophenyl)hydrazine 4-Nitrophenylhydrazine (32.0 g, 0.21 mole) was slurried in acetonitrile (500 ml) and the mixture was cooled to 0C. A solution of 4 chlorobenzoyl chloride (17.5 g, 0.10 mole) in acetonitrile (25 ml) was added dropwise to the cooled slurry. The reaction mixture was allowed to stand overnight. The mixture was filtered and the solid was washed with acetonitrile, then thoroughly with water.
The product was recrystallized from acetonitrile and de-colorized with charcoal to give a pale yellow solid. Yield 24.8 g (85%), m.p. 245.5-248.5C.
-49- i - ~

~06~363 .: .

33. 1-(4-Chlorobenzoyl)-2-(4-aminophenyl)-hydrazine hydrochloride _ , 1-(4-Chlorobenzoyl)-2-(4-nitrophenyl)hydrazine , (2.92g, 0.01 mole) and 5% palladium on barium sulfate (cata- ~ -lytic amount) were suspended in a mixture of ethanol (350 ml) and concentrated hydrochloric acid (5 ml) in a Parr shaker bottle. The reaction mixture was hydrogenated at room temperature until the theoretical amount of hydrogen had ~
been taken up. The reaction mixture was filtered and the i solvent was evaporated from the filtrate leaving a tan solid.
Yield 2.9 g (99%), m.p. 209C (dec.).

34. 1-{4-[2-(4-Chlorobenzoyl)hydrazino]phenyl~-3-phenylthiourea (NA-30) S `0~
-NH-C-NH-~ -NHNH-C-~ -CI

C2~Hl7CIN40S ;
1-(4-Chlorobenzoyl)-2-(4-aminophenyl)hydrazine hydrochloride (2.0 g, 0. oo67 mole) was mixed with ethanol (125 ml) and water (25 ml). Phenyl isothiocyanate (1.1 g, I
0.01 mole) was added to the mixture along with sodium ! ~ :
acetate (0.82 g, 0.01 mole) in water (10 ml). The reaction mixture was stirred and refluxed for 5 minutes, then was stirred at room temperature for one and one half hours.
The mixture was chilled in ice and then filtered. The pro-duct was washed with ethanol and dried to give an off-white solid. Yield 1.9 g (71%)~ m.p. 197.5-199C. i`

35. 1-{4-[2-(4-Cyanobenzoyl)hydrazino]phenyl}-3-phenylthiourea (NA-29) ,, s o 1:: --NH-C~NH-~ NHNH-C-~ -CN

Cz1Hl7NsOS

.~.
-50- Ii .~ .

~L~61363 Procedures (32.), (33.) and (34.) were repeated, but with 4-cyanobenzoyl chloride substituted for 4-chloro-benzoyl chloride. Yield 2.0 g (65%), m.p. 184-185C.

36. 1-{2-[4-Fluorobenzoyl)hydrazino]phenyl}-3-phenylthiourea (NA-31) _ ~
S O '',:~ ' -NH-C-NH--~ ~4-NHNH-C~ F

Procedures (32.), (33.) and (34.) were repeated, but with 4-fluorobenzoyl chloride substituted for 4-chloro- `~
benzoyl chloride. Yield 2.3 g (66%), m.p. 193-194C. -

37. 1-{4-[2-(4-Methylbenzoyl)hydrazino]phenyl}-3-phenylthiourea (NA-32) `~
S O
NH-C-NH-~ -C-~ -CHs Procedures (32.), (33.) and (34.) were repeated, but with 4-methylbenzoyl chloride substituted for 4-chloro-benzoyl chloride. Yield 1.9 g (50%), m.p. 185.5-187C.

38. 1-{4-[2-(4-Methoxybenzoyl)hydrazino]phenyl}-3-phenylthiourea (NA-33) _ _____ ~
S O 1' --~ 11 o---~ Il ~o---~ :
- N H - C - N H - ~ ~ - N H N H C ~ o = 4 ~ !

Procedures (32.), (33.) and (34.) were repeated, but with 4-methoxybenzoy-1 chloride substituted for 4-chloro-benzoyl chloride. Yield 2.5 g (71%), m.p. 177.5-178.5C. ¢

39. 3-Benzyl-1-{4-[2-(4-chlorobenzoyl)hydrazino]-phenyl}thiourea (NA-34) S O '' CH2-NH-C-NH-~ NHNH-C-o~ ~-CI

C21HloCIN~OS ~;

~61363 ",.......
1-(4-Chlorobenzoyl)-2-(4-aminophenyl)hydrazine ~,~
hydrochloride (1.5 g, 0.005 mole) was dissolved in hot ethanol (30 ml) under a nitrogen atmosphere. Benzyl isothiocyanate (0.82 g, 0.0055 mole) and potassium acetate (o.6 g, o.oo6 mole) were added and the mixture was refluxed under nitrogen for two -hours. The reaction mixture was cooled to room temperature, diluted with water (10-15 ml.) and chilled in ice. The product was filtered off, washed with ethanol and dried.
Recrystallization of the product from acetonitrile gave an `~
off-white solid. Yield 1.25 g (62%), m.p. 197-199C.

40. 3-Benzyl-l-{ll-C2-(4-rluorobenzoyl)hydrazino]-h_nyl ? t hi ourea (NA-35) S ', O ~ ' 9~ ~-CH2-NH-C-NH--~ ~-NHNH-C-~ ~--F
C 2 1HloFN405 Procedure (39.) above was repeated, but with 1-(4-fluorobenzoyl)-2-(4-aminophenyl)hydrazine hydrochloride ,~
substituted for l-(4-chlorobenzoyl)-2-(4-aminophenyl)hydra- , zine hydrochloride. Yield 0.7 g (35%), m.p. 185.5-187.5C. ,~
-C3-(2-Formylhydrazino)phenyl]-3-phenylthlourea (NA-36) ~`

Il .
NHNH-C-H `' I~-\1l S '-' ~-/ \NH-C-NH~
~.,.
Cl4Hl4N40S .
Procedures (1.), (3.) and (11.) were employed, but with 3-nitrophenylhydrazine in place of 4-nitrophenylhydrazine and phenyl isothiocyanate in place of methyl isothiocyanate. ~`;
Yield 2.8 g (62%), m.p. 143-145C.
42. 1-[3-(2-Formylhydrazino)phenyl]-3-(4-methoxy-phenylthiourea (NA-37) ~6~63 ~
o , :,.i ,;
NHNH~C-H

\NH-C-NH-~ -OCH~

C1sH1~N402S

.: Procedures (l.), (3.) and (ll.) were employed, but -with 3-nitrophenylhydrazine in place of 4-nitrophenylhydrazine and with 4-methoxyphenyl isothiocyanate in place Or methyl isothiocyanate. Yield 2.7 g (64~), m.p. 150-I52C.
43. l-[2-(2-Formylhydrazino)phenyl]-3-phenylthiourea ~NA-38) O '~i ' '' NHNH-C-H ~
I~ lol N H - C - N H- .~ ~ o Procedures (l.), (3.) and (18.) were employed~ but with 2-nitrophenylhydrazine in place Or 4-nitrophenylhydrazine and with phenyl isothiocyanate in place Or benzyl isothio-cyanate. Yleld 1.8 g (63~), m.p. 224-226C.

;::

- 53 ~

,`,,; : ~ .' '';~ ' ....
... .

l(~G1363 , ~ -44, 1-[4-(2-Acetylllydrazillo)phenyl]-1-benzyl-3-phenyl-thiourea (NA-40) - -O CHz-C6Hs H3C-C-NHNH-~ -N-C-NH-C6Hs S `' ' , , . ~
l-Acetyl-2-(4-benzylaminophenyl)hydrazine (2.80 g, .. 0.011 mole) and phenylisothiocyanate (1.35 g, 0.01 mole) were mixed in ethanol (25 ml) and the resulting mixture was refluxed for 5 minutes. The mixture was chilled in ice and water was added to precipitate the product. The product oiled out of solu-tion, but became crystalline upon standing and scratching. The j~
solid was filtered off and washed with wa~er, then ether. After drying the product was a pale yellow crystalline powder. Yield ~i~
3.0 g (77%), m.p. 114-117C. ;~

45. 1-[4-(2-Acetylhydrazino)phenyl]-1-(4-methoxy-benzyl)-3-phenylthiourea (NA-42) ,~.r,.

O CH2--~ ~o-OMe H3C-C-NHNH-~ N-C-NH-C6H5 ,;

C23H2~N~O~S

1 Acetyl-2-[4-(4-methoxybenzyl)aminophenyl]hydrazine (3.1 g, 0.011 mole) and phenylisothiocyanate (1.35 g, 0.01 mole) were mixed in ethanol (25 ml) and the resulting mixture was refluxed for 10 minutes The mixture was chilled in ice and diluted with water. The product oiled out of solution, but upon standing and scratching the substance solidified. The solid material was filtered off, washed with water and allowed to dry.
The material was stirred twice in a large volume of ether, then was filtered and washed with fresh ether. The product was a white powder. Yield 2.75 g (66%), m.p. 126-128C.
'`'~ ' . .
-54- ; :

1~6~L~63 . .

46. Comparison of single color photographic elements __ .
A control integral, single color photographic element, ;
Element 1, was prepared by coating the following layers in the order given on a poly~ethylene terephthalate) film suppGrt (coverages in parenthesis in g/m2 unless indicated):
(1) image-receiving layer of poly[styrene-co-N-benzyl-N,N-dimethyl-N-(3-maleimidopropyl)ammonium chloride] (2.2) and gelatin (2.2).
(2) reflecting layer Or titanium dioxide (21.5) and gelatin (2.2).
(3) opaque layer of carbon black (2.7) and gelatin (1.7).
(4) Compound Al (0.54) dispersed in gelatin (0.73).
(5) blue-sensitive, direct-positive, internal image gelatin-silver bromide emulsion of the type described in U.S.
Patent 3,761,276; (1.1 Ag, 2.2 gelatin), 5-sec-octadecyl-hydroquinone-2-sulfonic acid (20 g/mole silver) and nuc-leatlng agent compound H-25 (2000 mg/mole silver).

.

:;.,: ': - :

,' .

:

6~3~;3 Compound A CsHl1-t OH \ .
~ /CONH(CHz)40~ o-C5H
9~
. . .
NHSO2SO2NH;

NO2-~ -N=N
SO2CH3 ` :
Element 2 was identical to Element 1 except that the . :
.... . .
2000 mg/mole of nucleating agent H-25 was replaced with 4 :~
mg/mole of the compound NA~
Element 3 was identical to Element 1 except that ;
nucleating agent H-25 was replaced by 10 mg/mole o the compound NA-2. .. .
The above-prepared photosensitive elements were then .
exposed to a tungsten light source through a gxaduated step tablet in a sensitometer. The following processing composition was employed in a pod and was spread between the photosensitive element and a transparent cover sheet ~:
described below at about 15C and 38C by passing the transfer ~.
"sandwich" between a pair of juxtaposed rollers so that the li~uid layer was about 0.1 mm in thickness.
The cover sheet was prepared by coating in the order `
recited the following layers on a poly(ethylene terephthalate) .:~
.:, .
support~
(1) a polyacrylic acid layer (15.5 g/m2) .~. :
(2) a timing layer of a 95/5 mixture of cellulose acetate .. .
(40% acetyl and poly(styrene-co-maleic anhydride) (4.3 g/m2)~
The processing composition was as follows:

!
,'':

,: : . , . . . ., : . .

Potassium hydroxide. ,56.o g 4-Hydroxymethyl-4-methyl-1-8.o g phenyl-3-pyrazolidone 5-Methylbenzotriazole2.4 g t-Butylhydroquinone 0.2 g Sodium sulfite (anhyd)2.0 g Carbon 40.0 g Hydroxyethylcellulose25.0 g Water to make 1 liter . .
The results of the reflection densitometry read from the cyan dye image on the receiving layer through the film support of the laminated sandwich is shown in Table IV.
The nucleating agents NA-l and -2 give excellent rever- `
sal image discrimination at extraordinarily low levels compared to the nonadsorbed prior art fogging agent H-25. Much more satis- .
ractory Dmin values are obtained with NA-l and NA-2 at 38~C with :
some loss in e~fective speed. The action o~ NA-2 was surpris-ingly insensitive to the di~erence in processing temperature in Dmax, Dmin and in relative speed.

``;
, '~
,' '~,~` ':
','i' ;' .:: .,':
.' , . .
-5~

" .. ....

~0~;1363 :." . :.
, . . .

~ Z~
8 ~ ~co ``
~ .,, ~ ~ ~ ..
~ ooo ` . ~.
O X ~ OD CO ~ :

1 o o U~ ~; ~
U~ .. ~

~ ~ ooo . ..
~ Xl co ~ oo E~ ~ ~ ,i ,i .

~ ~ ~ . .
o ~r o _ o _ _ , F. ~ ~ ;
~,.
O ':
~ ~: ~
,1 ~ O ::
~' k _ :
~d a) ~ Ln ~
~1 U ~ I I ~ ~ . .
~ ~ I ~
z o m z z ~ ::
,~
.;
æ
~: ~I '. ' ' r; ~.'':

Z -.
:

--58-- .

.. . :, . , . . . , - , ~ . . , ~6~363 47. Additional Nucleating in Single Color Photographic Elements ~
., ~.
A plurality Or integral, single-color photographic elements were prepared in each instance by coating the following layers in the order given on a poly(ethylene terephthalate) film support (coverages in g/m unless indicated): -(1) image-receiving layer of poly(styrene-co-N-benzyl-N,N- ~
dimethyl-N-vinylbenzylammonium sulfate-co-divinyl `
benzene) (2.3) and gelatin (2.3) `
(2) reflecting layer of titanium dioxide (16.1) and gelatin (2.6) (3) layer of gelatin (1.2) (4) gelatin (1.2) and dye-releasing redox compound having the formula:
OH Cs~

f ~ - CONH(CH2)40~ -CsH11 -NHSOz-~ SOzCH3 SO2NH N=N-o\ /--NO2 ~^~

OH

(5) blue-sensitive, direct-positive, internal image gelatin-silver bromide emulsion of the type described in U.S.

Patent 3,761,276 (1.4 silver, 1.4 gelatin), 5-sec-octa-decylhydroquinone-2-sulfonic acid (16 g/mole silver) -and nucleating agent as given in Table V below.
Each of the above-described photographic elements ;
was exposed to a tungsten light source through a graduated step tablet in a sensitometer. A processing composition contained in a pod was spread at about 23C between the emul-. .~ , ..~

6~363 :~

.., :':
sion layer and a transparent cover sheet by passing the pod, the photographic element and the superimposed cover sheet between a pair of juxtaposed rollers so that the processing composition was forced from the pod and distributed between the cover sheet and the photographic element to form a liquid layer about 0.1 mm in thickness.
The cover sheet was prepared by coating the follow-ing layers in the order indicated onto a poly(ethylene tere-phthalate) film support:
(1) an acid layer comprised of poly(n-butyl acrylate-co-acrylic acid) (15.5) (70 weight percent acrylic acid); ~
(2) a timing layer comprising 5-(2-cyanoethylthio)-1- ,;;
phenyltetrazole (0.11), cellulose acetate (4.31) (40 weight percent acetyl) and poly(styrene-co-maleic ', anhydride) (0.11) and I -(3) polyacrylonitrile-co-vinylidene chloride-co-acrylic acid) (2.15). ~ -The cover sheet was oriented so that the coated side was j~, nearest the emulsion layer. I~
The pod contained the following processing composi- Ii tion: i~
Potassium hydroxide47.0 g Sodium hydroxide 3.4 g Methylhydroquinone0.1 g t-butylhydroquinone0.3 g 4-hydroxymethyl-4-methyl-1- ;
phenyl pyrazolidone12.0 g 5-methyl-1,2,3-benzotriazole 3.8 g carboxymethylcellulose 66.8 g dispersant 8.8 g ~
sodium sulfite (anhydrous) 1.0 g ~ , benzyl alcohol 1.0 g carbon 171.0 g distilled water to total volume 1 liter.

3~3 The results o~ the re~lection densitometry read from the yellow dye image on the receiving layer through film ~, support are given in Table V.
Table V
:, Conc ,~
Nucleating(mg/mole D D Rel.
Agentsilver) max mi_ Speed NA-16 6.0 1.78 0.28 100 ~-NA-12 4.3 1.86 0.26 71 NA-14 4.7 1.87 0.26 63 NA-l9 4.9 1.82 0.27 89 NA-23 6.6 1.83 0.28 55 NA-25 4.8 1.89 0.26 43 BA-26 5.2 1.86 0.27 71 NA-27 7.3 1.87 0.28 34 NA-15 12.8 1.72 0.28 120 NA-29 6.4 1.74 0.28 105 NA-30 8.8 1.76 0.28 102 ~--`
NA-31 8.3 1.80 0.27 102 NA-32 14.9 1.46 0.28 240 ;
NA-33 22.4 0.42 o.28 N.R.*
NA-16 5.0 1.87 0.30 100 ;
NA-20 5.4 1.89 0.26 35 ,~
NA-21 6.1 1.89 0.26 32 ,i;
NA-222 6.0 0.62 0.31 N.R.
NA-16 5.0 1.79 0.48 100 NA-282 10.0 0.33 0.31 N.R.
NA-34 7.2 2.00 0.48 27 NA-35 6.4 1.99 0.48 35 NA-37 33.2 0.68 0.28 N.R.
.., NA-362 6.41 0.66 0.56 N.R.
NA-382 6.41 0.49 0.49 N.R.
.,. ~ .
1 The activity of the processing composition was increased by the addition of 10 g/l of benzyl alcohol.
The image discrimination (Dm x minus Dm.n) was substantially increased in similarly prepare~, exposed land processed photograp~ic elements when the emulsion layer was coated at a pH in the range of from 4.8 to 5.0 instead of 6Ø , *N.R. = Not Recorded.

` ' , ,~' ' ' .

,. . .

. ,., , ~ , , . .. . . : . ~ , ~i1363 , 48- Comparison of multicolor photographic elements A control integral multicolor photographic element, Element 4, was prepared by coating the following layers in the order given on a poly(ethylene terephthalate) film support (coverages in parenthesis in g/m2 unless indicated):
(1) image-receiving layer of a poly[styrene-co-N-benzyl-N,N-dimethyl-N-vinylbenzyl-co-divinylbenæene~ latex (2.2) and gelatin (2.2).
(2) reflecting layer of titanium dioxide (21.5) and gelatin -(3.2).
(3) opaque layer of carbon black (2.7) and gelatin (1.7).
(4) cyan dye redox releaser Compound A (0.54) dispersed in gelatin (1.1).
(5) interlayer Or gelatin (Q.54). ~' (6) red-sensitive, direct-positive, internal image gelatin-silver bromide emulsion (1.2 Ag, 1.1 gelatin), 5-sec-octa-decylhydroquinone-2-sulfonic acid (16 g/mole silver~ and , nucleating agent H-25 (300 mg/mole silver).
(7) interlayer of gelatin (1~1) and 2,5-di-sec-dodecylhydro~
quinone (1.1).
(8) magenta dye redox releaser Compound B2 (o.54) in diethyl- ~`
lauramide (0.27) dispersed in gelatin (1.1).
(9) green-sensitive, direct-positive, internal image gelatin-silver bromide emulsion (1.35 Ag, 100 gelatin), 5-sec-octa- ;~
decylhydroquinone-2-sulfonic acid (16 g/mole Ag), and nucleating agent H-25 (400 mg/mole Ag).
(10) interlayer of gelatin (1.2) and 2,5-di-sec-dodecylhydro-quinone (1.1).
(11) yellow dye redox releaser Compound C3 (o.86) in diethyl-lauramide (0.43) dispersion gelatin (1.1).
.

-62- ~

i3 363 (12) blue-sensitive, direct-positive, internal-image gelatin-silver bromide emulsion (1.25 Ag, 1.1 gelatin), 5-sec-octa-decyl-5-hydroquinone-2-sulfonic acid (15 g/mole Ag), and nucleating agent H-25 (500 g/mole Ag). ~ :
(13) overcoat layer of gelatin (0.54) and 2,5-di-sec-dodecyl- ; ~
hydroquinone (0.11). . .:
, ~, ..

Compound B C5H11 t .. . .
~ /CONH(CHz)~O~ C5H-1 t :~ ::
.
NH CH3SO2NH-~
SO2-~ -N-N-~ -OH
\SO2NHC(CH3)3 ,'~ '~'' ~' 3 . :
Compound C ~-~
C H -t CONH(CH~) 90-~ ,H11 ~

NHS02 ~ /NHSO~ ~H ::

A series of analogous photographic elements, Elements ~, :
5 through 9, were prepared by substituting the acylhydrazinophenyl-thiourea fo.gging agents of the invention for nucleating agent : :
H-25 in the emulsion layers 12 (blue-sensitive), 9 (green- .
sensitive), and 6 (r~d-sensitive). ;~
The above-prepared photosensitive elements were then exposed ko a graduated density multicolor test ob~ect. The ,~,, .

': :

~11 6~363 following processing composition was employed in a pod and was J
spread between duplicate samples of the pho~osensitive element and the transparent cover sheet described below - one at 15G, the other at 38C - by passing the transfer "sandwich" between a pair of ~uxtaposed rollers so that the liquid layer was about 7Q microns in thickness. ~, The cover sheet was identical to that employed above in Example 46 tcomparison of single color photographic elements).
The processing composition was as follows: ;
Potassium hydroxide 56.C g 4-Hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone 8.o g 5-Methylbenzotriazole 2.4 g -~
t-Butylhydroquinone 0.2 g Sodium sulfite (anhyd) 2.0 g Carbon 100.0 g Carboxymethylcellulose 51.0 g Benzyl alcohol 10.0 ml Water to make 1.0 liter Table VI shows the maximum (DmaX) and minimum ~Dmin) dye densities in the image-receiving layer as read by reflec-tion densitometry through the film support of the laminate.
The speed values were taken at a density of 0.7 on the reversal sensitometric curve.
The data show good image discrimination resulting from the action of the incorporated nucleating agents in the image-forming layers. Control nucleating agent H 25 showed substantial speed losses on high temperature (38C) processing as compared to the low temperature (15C) processing. The adsorbed hydrazine `~
nucleating agents of the invention showed improved processing latitude both in regard to DmaX and speed changes. Some o~

~ -64-~6~3~3 ::

.' ' ' ~ .' O O r~ 3 03 co ';
~1 0 ~ '~ r~ 3 N i ~) 0 1~
bO ~-1 0 o o o o `, ~ O I + + I + I . .
t~l V r-l ~ .. .
S o ~ ~ r~ ~ ,~ 03 03 '"' ' .
V U~ ~ ~) 1~ r~ I ~ 0 3 r-l~r~
O o o o o o ,:' ':
a) ~ v I I I I + I ~. . .
a) o O ..
~ ~ ) ~ ~ O O "
U~ ~ ~) :5 ~ U~ ~O X ~ ~O ' ' r~
a:~ o o o o E~ ~ ~ ,' '' ' ~ ) rX) r~ r~ O 0~ 0C~ ~D 0~ `:;
r~ H t~)r~l t~ N ~)r--l ~ r-l N H 3 . . ::
~) . . . . . .. . . . . . .:
V V O O O O O O O O O O O O
o ~
~--1 coN N~ r--l O O r-l C
O N 3N L~N L~ N 3N ~1 N ~ ~:
~) ~ O OO OO O O OO O O O ;`` .:' ~ , . :. :
,~ a) 0330 ~00 N ~N ~ N3 N ~N 3 ~ N ~N ~N ~) L~ r-l .~ .. .. .. .. .. ' X O OO O o o o oo o o o .: .
. .
3 03 O~N 3 CO 3~D O N O
~ ¦ O N r~ ~i N~i ~i~ , o o . ,:
L~ o 3~ o 3 a) ~ Ll~~ ~;o c~ 3 03t~ U~
H ~ ~ .. .. .. .. .. ..
~d U ~--1 ~r--l Hr~ N.--I r--l r--l ~I H H `. :
~Ll ~C ,., :, ~_ 1 1~1 a)Lr~ o ~ D~1 3 0 ~ O '~C) '`, m ~ ~ ~3C~ 003 1~3~rX)r-l~ `"
CI~ ~ r-l E~ m ,~ Nr-l Hr--l NO r-lr~ H r~ H ; ~

O

~rl bO ~ ~. ;' ` .

¢ ~ 0 3 L~ ~ ~D rt ~ V' O o~ o ~ ' ~ '~. . ' ~ v ~ m o ,~
, ~; . .
~ ,~
_ ~' O Lf\N r-l r-l r-l \~ :
~r-/ ~, ~ ~l l l l l I , .
~1) 0 ~ I ¢ 'C '~ ¢ 'C ;' ~0¢ _ ~C Z Z Z Z Z ,;~ ' ,': ' ' ~r,:
'.
~ ..
3 1~
. ~ ,'.. ".:
~ '`' ~;: ', :' .

-64a-, .. . ...
. , .
, , ~6~L363 .
the hydrazides surprisingly showed an increase in speed on high temperature processing, especially in the red-sensitive layer.

49- Nucleating agent combinations An integral multicolor photograph:ic element, Element 10, was coated similarly as Elements 4 through 9, except that a combination of nucleating agents werè used in the green- and red-sensitive layers. The red-sensitive layer (6) contained (each in mg/mole of silver) H-25 (150) and NA-16 (6.4). The green-sensitive layer (9) contained compound H-25 (240) and NA-16 (4.8).
The blue-sensitive layer 12 contained only the nucleating agent NA-16 (11.0).
The element was exposed to a tungsten light through a t graduated density multicolor test ob~ect having 0.15 log E steps ¦~
and processed using a cover sheet as described above in connec-tion with Elements 4 through 9 at 15, 24, and 38C. The processing composition was formulated as follows:

Potassium hydroxide56.0 g 4-Hydroxymethyl-4-methyl-1-8.0 g !:
phenyl-3-pyrazolidone 5 Methylbenzotriazole2.4 g t-Butylhydroquinone 0.2 g Sodium sulfite 10.0 g Carboxymethylcellulose51.0 g Carbon 100.0 g 1,4-Cyclohexanedirnethanol 10.0 g Water 1000.0 g ~`,.
The sensitometric curves were obtained by color reflection densitometry at least three hours after lamination.
Representative densities and relative speeds (read at a density ~;
of 1.0) are given in the following table: Step 14 is the fourteenth density step in the above test object, wherein the test object has 21 density steps and Step 1 permits rnaximum exposure.

~063L363 `: ~ ~

TABLE VII
, Development Temperature C :

Density Red Dmin 0.22 0.23 o.56 Step 141.08 1.22 1.72 Dmax 1,66 1.92 2.28 Green Dmin 0. 21 0.24 0.52 Step 141.12 1.12 1.41 Dmax 1. 72 1.85 2.16 Blue Dmin 0. 26 0.27 0.45 ~:
Step 140.91 o. gl 1.26 Dmax 1.66 1.74 2.06 Relative Speed Red 100 91. 51 Green 100 100 66 Blue129 129 85 The data show that by adJusting the level ofnucleating agents that the sensitometry of each layer can be stabilized over the temperature range of 15 to 24C with the speed change on 38C
20 over-development being about the same for each layer (loss of less than one camera stop).
The invention has been described with particular reference to preferred embodiments thereof, but it will be under- -.:.
stood that variati.ons and modifications can be effected within ~. .
the spirit and scope of the invention.

, ~ . . .

.. .
. ' '.

. .
. , ~ , : ' .

. .. .
, . .

'' ' ' .

Claims (32)

WE CLAIM:

1. A radiation-sensitive silver halide emulsion comprising silver halide grains capable of forming an internal latent image when coated in a photographic element and exposed to actinic radiation characterized in that said emulsion further comprises a nucleating amount of an acylhydrazino-phenylthiourea wherein said acylhydrazinophenylthiourea has the formula:

wherein R is hydrogen; an alkyl, cycloalkyl, haloalkyl, alkoxy-alkyl or phenylalkyl substituent or a phenyl nucleus having a Hammett sigma-value-derived electron withdrawing characteristic more positive than -0.3;
R1 is a phenylene or alkyl, halo- or alkoxy-substituted phenylene group;
R2 is an alkyl, haloalkyl, alkoxyalkyl or phenylalkyl substituent having from 1 to 18 carbon atoms; a cycloalkyl substituent; naphthyl; a phenyl nucleus having a Hammett sigma-value-derived electron withdrawing characteristic less positive than +0.50 or R3 is hydrogen, benzyl, alkoxybenzyl, halobenzyl or alkylbenzyl;
said alkyl moieties, except as otherwise noted, in each instance include from 1 to 6 carbon atoms; and said cycloalkyl moieties have from 3 to 10 carbon atoms.

2. A radiation-sensitive silver halide emulsion as described in claim 1 wherein R is hydrogen, phenyl, alkylphenyl, cyanophenyl, halophenyl, alkoxyphenyl, alkyl, cycloalkyl, haloalkyl, alkoxyalkyl or a phenylalkyl substituent;
R1 is a phenylene or alkyl, halo- or alkoxy-substituted phenylene group;
R2 is an alkyl substitutent having from 1 to 18 carbon atoms; a cycloalkyl substituent; a haloalkyl, alkoxyalkyl or phenylalkyl substituent; phenyl or naphthyl;
an alkylphenyl, halophenyl or alkoxyphenyl substituent or ;
R3 is hydrogen, benzyl, alkoxybenzyl, halobenzyl or alkylbenzyl;
said alkyl moieties, except is otherwise noted, in each instance include from 1 to 6 carbon atoms; and said cycloalkyl moieties have from 3 to 10 carbon atoms.

3. A radiation-sensitive silver halide emulsion according to claim 2 wherein said alkyl moieties of R consist of from 1 to 4 carbon atoms.

4. A radiation-sensitive silver halide emulsion according to claim 2 wherein R1 is a para-phenylene group.

5. A radiation-sensitive silver halide emulsion according to claim 2 wherein said acylhydrazinophenylthiourea is chosen from the group consisting of 1-[4-(2-acetylhydrazino)phenyl]-1-benzyl-3-phenylthiourea and 1-[4-(2-acetylhydrazino)phenyl]-1-(4-methoxy-benzyl)-3-phenylthiourea.

6. A radiation-sensitive silver halide emulsion as described in claim 1 wherein R is a hydrogen, phenyl, 4-alkylphenyl, 4-cyano-phenyl, 4-halophenyl, 4-alkoxyphenyl, alkyl, cyclohexyl or phenylalkyl substituent, wherein said alkyl moieties have from 1 to 4 carbon atoms;
R1 is a para-phenylene or a 3 position alkyl, halo-, or alkoxy-substituted para-phenylene group; and R2 is an alkyl, haloalkyl, alkoxyalkyl or phenyl-alkyl substituent having up to 12 carbon atoms, a cyclohexyl substituent; phenyl or a 4-alkylphenyl, 4-halophenyl or 4-alkoxyphenyl substituent; wherein said alkyl moieties, except as otherwise noted, in each instance include from 1 to 6 carbon atoms.

7. A radiation-sensitive silver halide emulsion according to claim 6 wherein said acylhydrazinophenylthiourea is chosen from the group consisting of 1-[4-(2-formylhydrazino)phenyl-3-phenylthiourea;
1-[4-(2-acetylhydrazino)phenyl]-3-phenylthiourea;
1-[4-(2-benzoylhydrazino)phenyl]-3-phenylthiourea;
1-[4-(2-formylhydrazino)phenyl]-3-methylthiourea;
1-[4-(2-acetylhydrazino)phenyl]-3-ethylthiourea;
1-[4-(2-formylhydrazino)phenyl]-3-butylthiourea;
1-[4-(2-formylhydrazino)phenyl]-3-cyclohexylthiourea;
1-[4-(2-formylhydrazino)phenyl]-3-benzylthiourea;
1-[4-(2-formylhydrazino)phenyl]-3-heptylthiourea;
1-[4-(2-formylhydrazino)phenyl-3-decylthiourea;

1-[4-(2-formylhydrazino)phenyl]-3-(4-cyanophenyl)-thiourea;
1-[4-(2-formylhydrazino)phenyl]-3-(4-methoxy-phenyl)thiourea;
1-[4-(2-formylhydrazino)-3-methoxyphenyl]-3-phenylthiourea;
1-[4-(2-formylhydrazino)-3-methoxyphenyl]-3-butylthiourea;
1-[4-(2-formylhydrazino)-3-methoxyphenyl]-3-cyclohexylthiourea;
1-[4-(2-formylhydrazino)-3-methoxyphenyl]-3-(4-methoxyphenyl)thiourea;
1-[4-(2-trifluoroacetylhydrazino)phenyl]-3-phenylthiourea;
1 {4-[2-(4-cyanobenzoyl)hydrazino)phenyl}-3-phenylthiourea;
1-{4-[2-(4-chlorobenzoyl)hydrazino]phenyl}-3-phenylthiourea;

1-{4-[2-(4-fluorobenzoyl)hydrazino]phenyl}-3-phenylthiourea;
1-{4-[2-(4-methylbenzoyl)hydrazino]phenyl}-3-phenylthiourea;
1-{4-[2-(4-methoxybenzoyl)hydrazino]-phenyl}-3-phenylthiourea;
1-{4-[2-(4-chlorobenzoyl)hydrazino]phenyl}-3-benzylthiourea; and 1-{4-[2-(4-fluorobenzoyl)hydrazino]phenyl}-3-benzylthiourea.

8. A radiation-sensitive silver halide emulsion as described in claim 1 wherein said acylhydrazinophenylthiourea has the formula wherein R is a hydrogen, phenyl, 4-alkylphenyl, 4-cyano-phenyl, 4-alkoxyphenyl, alkyl, cyclohexyl or phenylalkyl substituent;
R1 is a para-phenylene or a 3 ring position alkyl, halo- or alkoxy substituted para-phenylene group; and said alkyl moieties in each instance include from 1 to 4 carbon atoms.

9. A radiation-sensitive silver halide emulsion according to claim 6 wherein said acylhydrazinophenylthiourea is chosen from the group consisting of 1,3-bis[4-(2-formylhydrazino)phenyl]thiourea;
1,3-bis[4-(2-acetylhydrazino)phenyl]thiourea; and 1,3-bis[4-(2-benzoylhydrazino)phenyl]thiourea.

10. A radiation-sensitive silver halide emulsion according to claim 1 wherein said acylhydrazinophenylthiourea nucleating agent is present in a concentration of from 0.1 to 200 mg per mole of silver.

11. A radiation-sensitive silver halide emulsion according to claim 1 wherein said acyhydrazinophenylthiourea nucleating agent is adsorbed to the surface of said silver halide grains.

12. A photographic emulsion comprising (a) a hydrophilic colloid, (b) radiation-sensitive silver halide grains which when coated on a support at a density from 3 to 4 grams/m2, exposed to a light intensity scale for a fixed time of from 1 X 10-2 to 1 second and developed for 5 minutes at 25°C in a surface developer of the composition indicated below pro-duce a maximum optical density of less than 0.4 and which provide an optical density of at least 0.5 optical density units less than when the above procedure is repeated addi-tionally including in the surface developer 0.5 gram per liter of potassium iodide to form an internal developer and (c) from 0.5 to 25 mg per mole of silver of acyl-hydrazinophenylthiourea as described in claim 6 and wherein the surface developer composition consists essentially of water (53°C) 500.0 cc N-methyl-p-aminophenol sulfate 2.5 grams sodium sulfite, desiccated 30.0 grams hydroquinone 2.5 grams sodium metaborate 10.0 grams potassium bromide 0.5 gram water to make 1.0 liter.

13. A photographic emulsion according to claim 12 wherein said acylhydrazinophenylthiourea is present in a concentration Or from 1 to 15 mg per mole of silver.

14. A photographic emulsion according to claim 12 wherein said acylhydrazinophenylthiourea is adsorbed to the surface of said silver halide grains and at least one other hydrazide, hydrazone or N-substituted cycloammonium quaternary salt nucleating agent is dispersed within said hydrophilic colloid.

15. A photographic emulsion according to claim 12 wherein said silver halide grains have metal dopants occluded therein and wherein said halide is predominantly bromide, which grains have been chemically sensitized on the surface thereof to a level which would produce a density of less than 0.4 when imagewise exposed and developed in a test surface developer for five minutes at 27°C, and to at least a level which would provide a density of greater than 0.5 in an undoped silver halide emulsion of the same grain size and halide composition when exposed and developed in the test surface developer, provided said emulsions are coated at a coverage of between about 3 and 4 grams per square meter.

16. In a photographic element comprised of a support, and as a coating thereon, a radiation-sensitive silver halide emulsion layer comprised of silver halide grains capable of forming an inter-nal latent image, the improvement comprising an acylhydrazinophenylthiourea nucleating agent incorporated within said radiation-sensitive layer of the formula wherein R is hydrogen; an alkyl, cycloalkyl, haloalkyl, alkoxy-alkyl or phenylalkyl substituent or a phenyl nucleus having a Hammett sigma-value-derived electron withdrawing characteristic more positive than -0.3;
R1 is a phenylene or alkyl, halo- or alkoxy-substituted phenylene group;
R2 is an alkyl, haloalkyl, alkoxyalkyl or phenyl-alkyl substituent havlng from 1 to 18 carbon atoms; a cyclo-alkyl substituent; naphthyl; a phenyl nucleus having a Hammett sigma-value-derived electron withdrawing characteristic less positive than +0.50 or ;

R3 is hydrogen, benzyl, alkoxybenzyl, halobenzyl or alkylbenzyl;
said alkyl moieties, except as otherwise noted, in each instance include from 1 to 6 carbon atoms; and said cycloalkyl moieties have from 3 to 10 carbon atoms.

17. In a photographic element according to claim 16 the further improvement wherein the acylhydrazinophenyl-thiourea is present in an amount of from 1 to 25 mg per mole of silver.

18. In a photographic element according to claim 16 the further improvement wherein the acylhydrazino-phenylthiourea is present in an amount of from 1 to 15 mg

19. In a photographic element according to claim 16 the further improvement in which said photographic emulsion additionally contains at least one other hydrazide nucleating means, hydrazone nucleating means or N-substituted cycloammonium quaternary salt nucleating means dispersed therein.

20. In an image transfer film unit which comprises an image-receiving layer, at least one layer of a photographic emulsion con-taining silver halide grains which are substantially unfogged on their surfaces and which are capable of forming an inter-nal latent image, and means containing and capable of selectively intro-ducing an alkaline processing composition into contact with said photographic emulsion layer, the improvement comprising a nucleating amount of an acylhydrazinophenyl-thiourea of the formula wherein R is hydrogen, an alkyl, cycloalkyl, haloalkyl, alkoxy-alkyl or phenylalkyl substituent or a phenyl nucleus having a Hammett sigma-value-derived electron withdrawing characteristic more positive than -0.3;

R1 is a phenylene or alkyl, halo- or alkoxy-substituted phenylene group;
R2 is an alkyl, haloalkyl, alkoxyalkyl or phenyl-alkyl substituent having from 1 to 18 carbon atoms; a cyclo-alkyl substituent; naphthyl; a phenyl nucleus having 2 Hammett sigma-value-derived electron withdrawing characteristic less positive than 0.50 or ;
R3 is hydrogen, benzyl, alkoxybenzyl, halobenzyl or alkylbenzyl;
said alkyl moieties, except as otherwise noted, in each instance include from 1 to 6 carbon atoms; and said cycloalkyl moieties have from 3 to 10 carbon atoms.

21. In an image transfer film unit according to claim 20 the further improvement in which said film unit includes an antifoggant.

22. In an image transfer film unit according to claim 20 the further improvement in which said film unit additionally includes hydrazide, hydrazone or quaternary ammonium salt nucleating means.

23. An image transfer film unit comprising (a) a photographic element including 1) a layer containing a blue-sensitive silver halide emulsion having associated therewith an immobile material capable of releasing a mobile yellow image dye, 2) a layer containing a green-sensitized silver halide emulsion having associated therewith an immobile material capable of releasing a mobile magenta image dye, and 3) a layer containing a red-sensitized silver halide emulsion having associated therewith an immobile material capable of releasing a mobile cyan image dye, wherein each of said silver halide emulsions comprises silver halide grains having metal dopants occluded therein, said grains being sub-stantially unfogged on their surfaces and being chemically sensitized on their surfaces 1) to a level which will provide a maximum density of less than 0.4 when developed in a test surface developer of the composition indicated below for 5 minutes at 27°C after exposure to a light intensity scale for a fixed time of from 1 x 10 2 to 1 second when said photosensitive composition is coated at a coverage of between about 3 and 4 g of sil-ver per square meter, and 2) to at least a level which would provide a maximum density of at least 0.5 using un-doped silver halide grains of the same grain size and halide composition when coated, exposed and developed in like manner, (b) an image-receiving layer, (c) means containing and adapted to introducing an alkaline processing composition into contact with said silver halide emulsions, (d) a silver halide surface developing agent located in said processing composition or said photographic element, and (e) from 0.5 to 25 mg per mole of silver of a nucleat-ing agent incorporated within at least one of said silver halide emulsion layers, said nucleating agent having the formula or wherein R is hydrogen, phenyl, alkylphenyl, cyanophenyl, halophenyl, alkoxyphenyl, alkyl cycloalkyl, haloalkyl, alkoxyalkyl or a phenylalkyl substituent;
R1 is a para-phenylene or 3-alkyl, 3-halo- or 3-alkoxy-substituted para-phenylene group;
R2 is an alkyl substitutent having from 1 to 12 carbon atoms; a cycloalkyl substituent; a haloalkyl, alkoxyalkyl or phenylalkyl substituent; phenyl or naphthyl;
or an alkylphenyl, halophenyl or alkoxyphenyl substituent;
R3 is hydrogen, benzyl, 4-alkoxybenzyl, 4-halo-benzyl or 4-alkylbenzyl;
said alkyl moieties of R have from 1 to 4 carbon atoms;
said alkyl moieties, except as otherwise noted, in each instance include from 1 to 6 carbon atoms; and said cycloalkyl moieties have from 3 to 10 carbon atoms;

the test surface developer consisting essentially of:

water (52°C) 500.0 cc N-methyl-P-aminophenol sulfate 2.5 grams sodium sulfite, desiccated 30.0 grams 2.5 grams sodium metaborate 10.0 grams potassium bromide 0.5 gram water to make 1 liter hydroquinone

24. An image transfer film unit according to claim 23 wherein said nucleating agent is present in at least said red-sensitive silver halide layer.

25. A compound having the formula wherein R is hydrogen; an alkyl, cycloalkyl, haloalkyl, alkoxyalkyl or phenylalkyl substituent or a phenyl nucleus having a Hammett sigma-value-derived electron withdrawing characteristic more positive than -0.3;
R2 is an alkyl, haloalkyl, alkoxyalkyl or phenalkyl substituent having from 1 to 18 carbon atoms; a cycloalkyl substituent, naphthyl; a phenyl nucleus having a Hammett sigma-value-derived electron withdrawing characteristic less positive than +0.50 or R3 is hydrogen, benzyl, alkoxybenzyl, halobenzyl or alkylbenzyl;
said alkyl moieties, except as otherwise noted, in each instance include from 1 to 6 carbon atoms; and said cycloalkyl moieties have from 3 to 10 carbon atoms.

26. A compound according to claim 25 wherein said alkyl moieties of R consist of from 1 to 4 carbon atoms.

27. A compound according to claim 25 wherein is a para-phenylene group.

28. A compound according to claim 25 wherein R is a hydrogen, phenyl, alkylphenyl, cyanophenyl, halophenyl, alkoxyphenyl, alkyl, cycloalkyl, haloalkyl, alkoxy-alkyl or phenylalkyl substituent;
R1 is a phenylene or alkyl, halo- or alkoxy substi-tuted phenylene group;
R2 is an alkyl, haloalkyl, alkoxyalkyl or phenyl-alkyl substituent having up to 18 carbon atoms; a cycloalkyl substituent; phenyl or naphthyl; an alkylphenyl, halophenyl or alkoxyphenyl substituent or ;

said alkyl moieties, except as otherwise noted, in each instance include from 1 to 6 carbon atoms; and said cycloalkyl moieties have from 3 to 10 carbon atoms.

29. A compound according to claim 28 wherein R2 is an alkyl substituent having from 1 to 12 carbon atoms; a cyclohexyl substituent; phenyl; or a 4-alkylphenyl, 4-halo-phenyl or 4-alkoxyphenyl substituent.

30. A compound according to claim 28 wherein R1 is a para-phenylene or para-phenylene substituted in the 3 position with an alkyl, halo- or alkoxy substituent.

31. A compound according to claim 25 wherein R is a hydrogen, phenyl, 4-alkylphenyl, 4-halo-phenyl, 4-alkoxyphenyl, alkyl, cyclohexyl or phenylalkyl substituent; wherein said alkyl moieties have from 1 to 4 carbon atoms, R1 is a para-phenylene or a 3 position alkyl, halo- or alkoxy substituted para-phenylene group; and R2 is an alkyl, haloalkyl, alkoxyalkyl or phenyl-alkyl substituent having up to 2 carbon atoms; a cyclohexyl substituent; phenyl; or a 4-alkylphenyl, 4-halophenyl or 4-alkoxyphenyl substituent; wherein said alkyl moieties, except as otherwise noted, in each instance include from 1 to 6 carbon atoms.

32. A compound having the formula wherein R is a hydrogen, phenyl, 4-alkylphenyl, 4-halo-phenyl, 4-alkoxyphenyl, alkyl, cyclohexyl or phenylalkyl substituent;
R1 is a para-phenylene or a 3 position alkyl, halo-or alkoxy substituted para-phenylene group; and said alkyl moieties in each instance include from 1 to 4 carbon atoms.