US3824103A - Photographic element,composition and process having an s-carbamoyl stabilizer - Google Patents

Abstract

S-CARBONYL SILVER SALT STABILIZER PERCURSORS ARE USEFUL IN PHOTOGRAPHIC ELEMENTS AND COMPOSITIONS FOR STABIILIZING AN IMAGE IN PROCESSING BY HEAT OR BY TREATMENT WITH AMMONIA OR AMINE VAPOR. THE PHOTOGRAPHIC ELEMENTS AND COMPOSITIONS CAN CONTAIN ADDENDA EMPLOYED IN PHOTOGRAPHIC MATERIALS SUCH AS SILVER HALIDE DEVELOPING AGENTS.

Description

United States Patent 3,824,103 PHOTOGRAPHIC ELEMENT, COMPOSITION AND PROCESS HAVING AN S-CARBAMOYL STABILIZER Zona R. Pierce and Grant M. Haist, Rochester, Jon T. Staples, Pittsford, and David A. Pupo, Churchville, N.Y1.\,I gzssignors to Eastman Kodak Company, Rochester, No Drawing Filed May 8, 1972, Ser. No. 251,728

Int. Cl. G03c l/34 U.S. Cl. 96--109 12 Claims ABSTRACT OF THE DISCLOSURE S-car-bamoyl silver salt stabilizer precursors are useful in photographic elements and compositions for stabilizing an image in processing by heat or by treatment with ammonia or amine vapors. The photographic elements and compositions can contain addenda employed in photographic materials such as silver halide developing agents.

BACKGROUND OF THE INVENTION Field of the Invention Description of the State of the Art The use of various sulfur-containing compounds as stabilizer precursors in photographic elements designed for processing with heat is known. These are described, for example, in U.S. Pat. 3,301,678 of Humphlett et al., issued Jan. 31, 1967; U.S. Pat. 3,506,444 of Haist et al., issued Apr. 14, 1970; U.S. Pat. 3,573,048 of Boller et al., issued May '30, 1971; U.S. Pat. 3,531,285 of Haist et al., issued Sept. 29, 1970; and Belgian Pat. 763,751 issued Sept. 3, 1971. A useful class of stabilizer precursors includes compounds which are based on thiuronium derivatives as described in these references. In some instances, the stabilizer precursors have not been entirely satisfactory because they often require higher than desired temperatures in processing of photosensitive materials designed for processing with heat. Temperatures of about 190 C. to about 220 C. have been employed with such stabilizer precursors which has presented problems with the film support which is employed. Cellulose acetate film, for example, can soften at about 100 C. and polyester film supports can undergo distortion at about 160 C. It has been desirable to provide stabilizer precursors which enable use of lower processing temperatures.

Processing employing vapors of ammonia or amines has also been described in the art. U.S. Pat. 2,410,644 of Fierke et al., issued Nov. 5, 1946 describes employing ammonia or amines in processing of photographic elements containing a silver halide emulsion in a silver halide developing agent. Development of the emulsion, however, does not take place in a substantially dry state but is carried out in the presence of water by the application of steam or water vapor. Moreover, an additional step is required to stabilize the image. Processing employing ammonia or amine vapors with incorporated thiuronium stabilizer precursors is described in copending U.S. Appli- 3,824,103 Patented July 16, 1974 cation Ser. No. 224,935 of King, filed Feb. 9, 1972, now abandoned. There has been a continuing need to provide photosensitive materials containing certain stabilizer precursors which can be processed with heat or with ammonia or amine vapors.

There accordingly has been a need to provide .photosensitive materials and processes, such as processing with heat or ammonia or amine vapors, which enable substantially dry stabilization of a developed image without subsequent processing steps.

SUMMARY OF THE INVENTION It has been found according to the invention that stabilization of a developed image as described can be provided by a stabilizing concentration of about 0.25 to about 20 moles per mole of photosensitive silver salt of an S-carbamoyl silver salt stabilizer precursor in photosensitive silver salt elements, compositions and processes for stabilizing a developed image employing heat or ammonia or amine vapors. Such photosensitive materials which are designed for processing with heat containing the described S-carbamoyl silver salt stabilizer precursors enable lower processing temperatures to be employed and/or improved.

DETAILED DESCRIPTION OF THE INVENTION A range of S-carbamoyl silver salt stabilizer precursors can be employed according to the invention. One test for suitable S-carbamoyl silver salt stabilizer precursors is described in Example 1 wherein the S-carbamoyl silver salt stabilizer precursor is employed in a photosensitive material for processing with heat. A test for suitable S-carbamoyl silver salt stabilizer precursors in processing with ammonia or amine vapors is described in Example 2.

A useful class of S-carbamoyll silver salt stabilizer precursors includes compounds represented by the formula:

wherein R and R are each selected from the group consisting of hydrogen, alkyl, especially alkyl containing 1 to 5 carbon atoms such as methyl, ethyl, propyl, butyl and pentyl, aryl, e.g. phenyl and tolyl; and SR is a sulfur containing moiety which has the property of cornplexing with photosensitive silver halide in the presence of heat or alkali. The alkyl and aryl radicals and the sulfur containing moiety can contain substituent groups which do not adversely affect stabilizing action or desired properties of the described silver salt stabilizer precursor or the photosensitive material in which the precursors are employed. Typical examples of substituent groups which do not adversely afiect the activity of the stabilizer precursor include methyl, ethyl, propyl, isopropyl, tertiary butyl and n-butyl. The described compounds also include salts of such compounds, such as amine salts, which do not adversely aifect the activity of the stabilizer precursor. The described sulfur-containing moiety which has the property of complexing "with photosensitive silver halide in the presence of heat and/or alkali, is a moiety which will cleave or be released from the described carbamoyl stabilizer precursor at elevated temperatures or in the presence of alkali such as ammonia or amine vapors and complexes or combines with a photosensitive silver salt such as photosensitive silver halide in unexposed areas of a photosensitive silver salt material, such as a photosensitive silver halide emulsion, forming a mercaptide compound which is more stable to light, atmospheric conditions and ambient temperatures than the photosensitive silver salt. A suitable sulfur-containing moiety which has the property of complexing with photosensitive silver halide in the presence of heat or alkali includes a moiety represented by the formula:

wherein R is amino, alkyl, especially alkyl containing 1 to 4 carbon atoms such as methyl, ethyl, propyl and butyLcarboxyl, carboxyalkyl containing 2 to 5 carbon atoms, such as carboxymethyl, carboxyethyl, and carboxypropyl, aminomethyl, sulfoalkyl containing 1 to 4 carbon atoms, e.g. sulfornethyl and sulfoethyl, morpholinomethyl, or a group represented by the formula:

SOs

SCHCOOH A range of carbamoyl moieties can be employed in the described S-carbamoyl stabilizer precursors. Examples of suitable carbamoyl moieties include the following:

ll --CNHCH2CH2 O CHzCHa I] -CN CHzCHa C NHOHZOHZCHgCHZ Typical S-carbamoyl silver salt stabilizer precursors include compounds represented by the formula:

wherein R is hydrogen or alkyl containing 1 to 5 carbon atoms; R is selected from the group consisting of alkyl containing 1 to 5 carbon atoms, phenyl and benzyloxy; R is amino, alkyl containing 1 to 4 carbon atoms, carboxyl, carboxyalkyl containing 2 to 5 carbon atoms, aminomethyl, sulfoalkyl containing 1 to 4 carbon atoms such as sulfomethyl and sulfoethyl, morpholinomethyl, or

wherein R is alkyl containing 1 to 4 carbon atoms; R is hydrogen or alkyl containing 1 to 4 carbon atoms; and R is hydrogen or carboxyl. These compounds include salts such as amine salts which do not adversely affect the activity of the stabilizer precursor.

In certain cases the S-carbamoyl silver salt stabilizer precursor can be a polymer containing the S-carbamoyl moiety. A suitable polymer containing the S-carbamoyl moiety is cop0ly[viuyl methyl ether-N-(ethylcarbamoylthioethyl)ma1eamic acid]. In instances where an S-carbamoyl silver salt stabilizer precursor which is a polymer is employed, the polymer can replace part of a binder or vehicle employed in the photosensitive material in which the stabilizer precursor is employed.

Especially useful S-carbamoyl silver salt stabilizer precursors include: 5

S-ethylcarbamoyl-Z-mercaptoisobutyric acid, dicyclohexylamine salt, S-ethylcarbamoyl-Z-mercaptoethylamine, p-toluene sulfonic acid salt, fl-(Ethylcarbamoylthio)propanesulfonic acid, guanidinium salt, and S-ethylcarbamoyl-N-acetyl-Z-mercaptoethylamine.

The described S-carbamoyl silver salt stabilizer precursors can be prepared by procedures known in the art. For instance, procedures described in St. Guttmann, Helv. Chem. Acta, 40:83 (1966) are suitable.

The described S-carbamoyl silver salt stabilizer precursors can be employed in a range of physical locations in a photographic system. They can be employed in one or more layers of a photographic element and/or in a processing composition if desired. The optimum location will depend upon the desired image, processing conditions, particular photographic system and the like. The S-carbamoyl silver salt stabilizer precursors are preferably employed in a location contiguous to the photosensitive component which is to be stabilized. For example, the stabilizer precursors can be incorporated into one or more layers of a photographic element such as a photographic silver halide emulsion layer, a layer between the support and the photographic silver halide emulsion layer, and/ or an overcoat layer.

One embodiment of the invention is a photographic element comprising a support having thereon a photosensitive silver salt and an S-carbamoyl silver salt stabilizer precursor as described. A range of concentration of the described silver salt stabilizer precursor can be employed in a photographic element depending upon the desired image, developing agent employed, processing conditions, particular stabilizer precursor and the like. The concentration of stabilizer precursor which is suitable is usually at least about 0.25 moles of the stabilizer precursor for each mole of photosensitive silver salt present to be stabilized. Suitable concentrations include about 0.25 moles to about 20 moles of the stabilizer precursor for each mole of silver halide. However, it is often desirable to use molar excesses of the stabilizer precursor to assure effective stabilization of the photosensitive silver salt to be stabilized. In some cases it can be desirable to employ at least 5 to 10 times the required amount of stabilizer precursor.

Various photosensitive silver salt materials can be stabilized employing the described stabilizer precursors. Typically the photosensitive silver salt materials are photosensitive silver halide materials. These include any photosensitive silver halide such as silver chloride, silver bromide, silver bromoiodide, silver chlorobromoiodide or mixtures thereof. The silver halide materials which are suitable are described, for example, in the Product Licensing Index, Vol. 92, December 1971, publication 9232, pages 107-110 in paragraphs I, II and III. A photosensitive silver halide useful in the invention can be chemically sensitized as described in paragraph III of this Product Licensing Index Publication.

The photosensitive silver halide materials and compositions according to the invention can contain various addenda which do not adversely affect the stabilizing action of the described stabilizer precursors. These include development modifiers, antifoggants, hardeners, plasticizers and lubricants, coating, aids, matting agents, brighteners and spectral sensitizing dyes as described in the Product Licensing Index, Vol. 92, December 1971, publication 9232, pages 107-110. The photographic elements useful according to the invention can contain antistatic and conducting layers and light-absorbing and filter dyes as described in this publication.

Another embodiment of the invention is a photosensitive composition comprising a photosensitive silver salt, such as photosensitive silver halide, and an S-carbamoyl silver salt stabilizer precursor as described.

A photographic element and/ or composition described according to the invention can contain various colloids alone or in combination as vehicles, binding agents and in various layers. Typically hydrophilic materials are employed in those instances where aqueous solutions are to be used in processing. However, in those instances in which the photosensitive material is for processing with heat, a hydrophobic binder can be used. Accordingly, hydrophilic and/ or hydrophobic materials can be employed as binders depending on the particular photosensitive material and the intended processing. Suitable hydrophilic materials include naturally-occurring substances such as proteins, for example, gelatin, 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(vinyl pyrrolidone), acrylic polymers and the like. Other synthetic polymeric compounds which can be employed include dispersed vinyl compounds such as in latex form and particularly those which increase dimensional stability of photographic materials. Suitable synthetic polymers include those described in the Product Licensing Index, Volume 92, December 1971, publication 9232, pages 107- 110 in paragraph VIII.

The photosensitive materials and other layers of a photographic element according to the invention can be coated on a wide variety of supports. Typical supports include cellulose nitrate film, cellulose ester film, poly- (vinyl acetal) film, polystyrene film, poly(ethylene terephthalate) film, polycarbonate film and related films or res inous materials as well as glass, paper, metal and the like. Typically a flexible support is employed, especially a paper support which can be partially acetylated or coated with baryta and/or an alpha olefin polymer particularly a polymer of an alpha olefin containing 2 to 10 carbon atoms such as polyethylene, polypropylene, ethylenebutene copolymers and the like.

The photosensitive silver salt materials employed according to the invention can be X-ray or other non-spectrally sensitized material or they can contain spectral sensitizing dyes as described.

The sensitizing dyes and/or other addenda such as the described stabilizer precursors according to the invention, can be added from water solutions or suitable organic solvent solutions can be used. The compounds can be added using various procedures known in the photographic art as described in the aforesaid Product Licensing Index Publication.

The described stabilizer precursors can be employed in combination with any silver salt developing agent or developing agent precursor which does not adversely alfect the stabilizing action of the stabilizer precursor and which provides the desired developing activity. Suitable silver halide developing agents which can be employed in combination with the stabilizer precursor described include, for example, polyhydroxybenzene developing agents such as hydroquinone, alkyl-substituted hydroquinones as exemplified by tertiarybutyl hydroquinone, methylhydroquinone, 2,5-dimethylhydroquinone and 2,6-dimethylhydroquinone, catechols and pyrogallol; chloro-substituted hydroquinones such as chlorohydroquinone or dichlorohydroquinone; alkoxy substituted hydroquinones such as methoxyhydroquinone or ethoxyhydroquinone; aminophenol developing agents such as 2,4-diaminophenols and methylaminophenols; ascorbic acid developing agents such as ascorbic acid, ascorbic acid ketals and other ascorbic acid derivatives; hydroxylamine developing agents such as N,N-di(2-ethoxyethyl)-hydroxylamine; 3-,

pyrazolidone developing agents such as 1-phenyl-3-pyrazolidone and/or 4 methyl-4-hydroxymethyl-l-phenyl-3- pyrazolidone; and the like.

A range of concentration of the described developing agents can be employed wtih a range of concentrations of the described stabilizer precursor. A typical concentration range of the described silver halide developing agent is about 2 moles to about 1 mole of the silver halide developing agent per mole of photosensitive silver halide to be developed.

The described silver halide developing agents can be employed in a range of photographic processing compositions, such as in photographic silver halide developer compositions, hardener compositions, monobaths and the like which can be employed in processing of a photographic element containing the described stabilizer precursor. The described silver salt developing agent can be employed in addition in the described photographic element.

After exposure, the resulting latent image in a photographic element containing the described stabilizer precursor and a suitable silver salt developing agent, as described, can be developed and stabilized by contacting the element with an alkaline development activator. Especially suitable alkaline development activators include ammonia or amine vapors. Vapor processing employing ammonia or amine vapor which can be performed according to the invention is suitable for single exposure holographic interferometry. This procedure is described, for example, in the Principles of Holography by Howard H. Smith, 1969, John Wiley, New York, N.Y. Employing ammonia or amine vapors for processing the latent image can be developed and stabilized at a range of temperatures and time. Typically vapor processing is carried out so as to provide a developed and stable image at about 15 C. to about 70 C. within about one to about 60 seconds.

Other development activators which can be employed in the practice of the invention include any of those which are alkaline development activators such as inorganic alkalies including, for example, sodium hydroxide, potassium hydroxide and/or lithium hydroxide, alkali metal carbonates such as sodium carbonate and potassium carbonate, alkali metal phosphate, such as trisodium phosphate and/or organic alkaline development activators such as quaternary ammonium bases and salts as well as amino alkanol and similar alkaline materials and/or alkaline release materials. The described development activators can be applied to the described photographic element containing the developed image and the stabilizer precursor in any suitable manner including, for example, dipping, spraying and/or suitable surface applications such as with rollers or other mechanical means.

The pH of the composition which is sufficient to activate the described stabilizer precursor and a developing agent should be sufiicient to provide a pH of about 8.0 to about 13.0.

Concentrations of moisture can be present in the described photographic elements which are usually present in conventional photographic paper supports under ordinary conditions, such as at 25 C. at 40% relative humidity. Small concentrations of moisture can provide beneficial effects in aiding the cleaving action of the described stabilizer precursor.

Another embodiment of the invention is a photographic process for developing and stabilizing an image in a photographic element comprising a support having thereon a photosensitive silver salt, a silver salt developing agent,

and an S-carbamoyl silver salt stabilizer precursor as decomprising a support having thereon a photosensitive silver salt and an S-carbamoyl silver salt stabilizer precursor comprising heating the photographic element to about C. to about 200 C. until the desired stabilized image is provided.

By increasing or decreasing the length of time of heating, a higher or lower temperature within the described range can be employed. Typically a developed and stable image is provided within about one to about 60 seconds.

Any suitable means can be used for providing the desired processing temperature range. The heating means can be a simple hot plate, roller or the like.

The following examples are included for a further understanding of the invention.

Example 1 A photosensitive composition is prepared by mixing the following components:

Gelatitn (pigskin gelatin, 12% by weight gelatin in aqueous 50 ml.

solu on Surfactant (10% by weight in aqueous solution), alkyllml.

ohenoxypoly(hydroxypropyleneoxide).

S-methylbenzotriazole. 0.1 g.

Gelatino silver chloride emulsion (a fine-grain silver chloride 10.0 ml.

gelatino emulsion in which the silver halide is predominantly silver chloride as described in British Patent. 1,063,844) (42 mg. of silver per ml.).

Bis(vinylsu1fonylrnethyl) ether 0.2 g-

After mixing, the resulting composition is coated on a polyester film support at 45 milligrams of silver per square foot. The resulting photographic element is sensitometrically exposed to tungsten light. The exposed photographic element is processed by contacting the side of the photo graphic element opposite the photosensitive coating with a heated metal block at C. for 15 seconds. A light stable, developed image is produced having a black tone with a transparent background and having a straight line gamma of 0.75 with a maximum density of 1.2.

In the absence of the described carbamoyl compound in the photographic element, the image developed is unstable producing darkening upon exposure to light.

Example 2 The procedure set out in Example 1 is repeated with the exception that after sensitometric exposure the photographic element is treated with ammonia fumes for 90 seconds at about 20 C.

A developed stable image having a clear background is produced with a gamma of 1.2 at a maximum density of 1.4.

Example 3 The procedure set out in Example 1 is repeated with the exception that the photographic element after sensitometric exposure is processed by immersion for 10 seconds in an aqueous alkaline solution at 20 C. containing 5% by weight sodium hydroxide, 10% by weight sodium sulfite and 5% by Weight sodium sulfate. The photographic element after processing is squeegeed to remove excess processing solution but is not washed before drying. The resulting developed stable image has a minimum density of 0.06, a maximum transmission density of 0.63 and a gamma of 0.46.

Higher transmission densities are obtained by rebalancing the components of the photographic element for this type of solution processing. No attempt is made to provide optimum concentrations of components in this example.

i 9 Examples 4-33 A coating composition is prepared by mixing the following components:

Gelatin (pigskin gelatin, 12% by weight in aqueous solution) 50 ml.

Surfactant (surfactant from Example 1, 10% by weight in aqueous solution) lml. Stabilizer precursor 0.01% of molecu- 10 l-phenyl-B-pyrazolidone lar weight. S-methylbenzotriazole 1 g.

Photographic silver chloride emulsion 0.1 g.

(42 milligrams of silver per ml.) 10 ml.

The stabilizer precursors employed in this composition are listed in the following Table I."

A photographic element is prepared employing this composition by coating on a polyester film support at a concentration of 45 milligrams of silver per square foot.

The resulting photographic element is sensitometrically exposed to tungsten light. The exposed photographic element is then processed by contacting the side of the element opposite the photosensitive coating on a heated metal block at 160 C. for 15 seconds. The results and the stabilizer precursor as well as any composition variation is listed in following Table H.

TABLE I I 13? Name Structure 1 S-(N-ethylaminocaroonyD-L-cysteine O CHaCHzNH'J-S-CHrCHC 0 011 2 SgfiyicarbamoyH-mercaptopropionic acid, dicylohexylamine CHsCHzNHC-S-CHCO 0- HI H2(C| u)1 3 B-ggzylcarbamoyl-3-mercapto-propionic acid, dicyclohexylamine CH:CHaNHCS-CH:CH;C 0 0" NHzWuHu): 4 S-ethyicarbamoyl-2mereaptoisobutyr1c acid, dieyclohexylamine 0 CH;

salt omcnmnd-s-c-coo- I fi awcHnh 5 S-ethylcarbamoyl-2,2-dimethyl-B-mercaptopropiouic acid, 0 H;

dieyclohexylamine salt. I] I Y CHlCHBNHC-'SCHICCOO' H: Ha( |Hu):

6 Copoly 1 [vinyl methyl ether-N-ethylcarbamoyl(thioethyl) C O OH maleamic acid]. CHlCH (([IH C H) :0 (3H1 I IH H CH; SC--NH-CH;CH1

7 S32110arbamoyl-Z-mercaptoethylamine, p-toluenesuli'onic acid %0 CH;CHNHC S-C HaCHgNHg 8 S-ethylcarbamoyl-Z-mercaptopropionic acid. %0

CH:CHzNHC--SCHC 0 OH (I) H; 9...-:..... 3-(ethylcarbam0y1thi0)pr0panesulfonic acid, sodium salt. .:-:.z:; O

CHxCHzNH9-S-CH:CH:CH S OINQ 10.....n:. s-gfinylearbamoyl-2-mercaptoethylamine, p-toiuenesulionie acid See footnote at end of table.

TABLE I-Continued C d. N8. Name Structure 2 2-[3-(ethoiry carbonylmethyl)ureido1ethyl N-(ethoxy carbonylmethyDthiocarbamate. ll ll CHaCHz-CCH:NHOS-CHnCHiNHCNH- (I? -CHC-OCHCH;

23 N-(ethylcarbamoylthioethyl)-N-methylmorphollnium p-toluene- O CH;

sulfonate. H

CHsCHaNHC-S-CHzClh-N 1 Dilficulty is encountered in coating this compound.

TABLE II Silver Comcoverage Image density ound Ex. Composition mg. o. No. variation Ag it!) Dmax, Dmi... Light stability Background Remarks 4 47. 5 0. 73 0W Light stable in sec., at 140 C. 5 0 5X stab. 48.1 0.58 6 GAL..- 45.5 0.84 Light stable in 5 see., 140 C. 7 GAL..... 41.4 0.57 Do. 8 GAL 48.4 0.72 Do. 9 GAL 49.5 0.95 Poor coating (low 501.). Light stable in 5 sec., at 140 C. 7 10 GAL 88.7 0.95 Almost light stable in 10 sec. at 140 C, 7 11 41.4 1.00 Almost light stable in 10 sec, at 140 O Brown image, clear background with yellow tint with 60 second ammonia treatment. 12 43. 2 1.14 0.06 .do Transparent hazy. Almost light stable in 20 seconds, 140 C. 13 43. 3 1. 26 0. 07 -....do -.do Almost light stable in seconds, 140 C. 14 46.7 0.62 0.16 Partially stabilized. 15 .8 0. 28 0.12 Stable Transparent hazy- Uneven: c gggigg. Almost light stabl in 15 see. a 16 5-MBTAZ 43.1 0.92 0.10 Partially stabilized. 17 fi-MBTAZ 42.0 0.92 0.07 Stable Transparent hazy. Light stable in 15 sec. at 140 C, Al t light stable in 15 sec. at 130 C. 1s 5-MBTAZ,1.33X 42.1 0.94 0.09 do Pale tan; hazy....- Light stable in 15 sec. at 140 0, Almost stab. light stable in 15 sec. at 130 C. 19 5-l;igAtZ,bASC, 40.6 0.78 0.20 -do Tan; hazy s a 20 fi-MBTAZ 36.0 0.85 0.06 ...-..d0 Clear Light stable in 15 sec. at 140 0, Al t light stable in 15 see. at 130 C. 21 5-MBTAZ 41.3 1.22 .do Orange...-: 22 5-MBIAZ,PTP 45.3 1.05 do 23 s-MBTAZ 38.7 1.38 do Yellow-tan: almost opaque. 24 S-MB'IAZ. 36.0 0.85 Clear Lilgihltltstgbtlfi iin see. a; 140 C. llmost sa e 11 soon sat130 25 5-MB'lAZ 41.3 1.22 Orange g e 26 5-MB'IAZ,PTP 45.3 1.05 do 27 S-MBTAZ 38.7 1.38 0 Yellow-tanalmost;

opaque. 28 5-MBTAZ.....' 39.4 0.12 0 Very paleyellow; Pie-stabilized.-

azy. 29 5-MB1AZ 41.3 0.70 0 Almostl' ht t b i 1 30 s 40.6 L07 0 ig s a lo n 5sec at 140 C 31 fi-MBTAZ... 38.0 0.50 0 32 5-MBTAZ 40.0 0. 93 0 Poor coating (granular). 33 b-MBTAZ 45.0 0. 70 0 Light stable in 15 sec. at 140 0. Almost light stable in 15 sec. at 130 C.

l G AL=D-ga1actonamlde (3 grams): 0.5X stab. 0.33 stab.=% or 36 stabilizer level indicated in example: 5-MBTAZ=0.1 ram additional 5-meth lbenzotrlazole; PlP =phenidone replaced with 2-propy1-4,5,6-trlhydroxypyrimidine (1 gram); ASC=acetone semicarbazone grams). y

1 (Comparative example.)

tures of about 130 C. it is usually desirable that the structure of the carbamoyl compound not contain a carboxyl or sulfonate group if increased stability of the developed image to light is to be obtained within a reduced processing time.

The S-ethylcarbamoyl-Z-mercaptoisobutyric acid, dicyclohexylamine salt produces an unusually clear and colorless background in the described photographic element.

In general, activation of the described photographic element with ammonia produces a higher maximum density and higher contrast than processing with heat.

In some instances a further advantage of certain of the carbamoyl stabilizer precursors as described is provided when the sulfur moiety is an antisludging agent upon release from the carbamoy'l moiety. Such antisilvering and/or antisludging activity is provided when the carbamoyl moiety is released from an antisludging agent such as Z-mercaptoisobutyric acid. Release of small concentrations of the antisludging agent into the processing solution during processing can provide inhibition of silvering.

The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

What is claimed is:

1. A photographic element comprising a support having thereon a photosensitive silver salt in association with a stabilizing concentration of about 0.25 to about 20 1 moles of an S-carbamoyl silver salt stabilizer precursor per mole of said silver salt.

2. A photographic element as in claim 1 wherein said S-carbamoyl silver salt stabilizer precursor is a compound represented by the formula:

wherein R and R are each selected from the group consisting of hydrogen, alkyl containing 1 to 5 carbon atoms, phenyl, and tolyl, and S-R is a sulfur containing moiety which has the property of complexing with photosensitive silver halide in the presence of heat or alkali.

3. A photographic element as in claim 1 wherein said S-carbamoyl silver salt stabilizer precursor is a compound represented by the formula:

wherein R is hydrogen or alkyl containing 1 to 5 carbon atoms; R is selected from the group consisting of alkyl containing 1 to 5 carbon atoms, phenyl and benzyloxy; R is amino, alkyl containing 1 to 4 carbon atoms, carboxyl, carboxyalkyl containing 2 to 5 carbon atoms; aminomethyl, sulfomethyl, morpholinomethyl, or

o -oH2NHi JNH-R wherein R is alkyl containing 1 to 4 carbon atoms; R is hydrogen or alkyl containing 1 to 4 carbon atoms; R is hydrogen or carboxyl.

4. A photographic element as in claim 1 wherein said S-carbarnoyl silver salt stabilizer precursor is copoly[vinyl methyl ether-N-(ethylcarbamoylthioethyl)maleamic acid].

5. A photographic element as in claim 1 wherein said S-carbamoyl silver salt stabilizer precursor is a compound selected from the group consisting of S-ethylcarbamoyl-2-mercaptoisobutyric acid, dicyclo' hexylamine salt, B-ethylcarbamoyl-2-mercaptoethylamine, p-toluenesulfonic acid salt, 1 Beta-(Ethylcarbamoylthio)propanesulfonic acid guanidinium salt, and S-ethylcarbamoyl-N-acetyl-Z-mercaptoethylamine.

6. A photosensitive composition comprising a photosensitive silver salt in association with a stabilizing concentration of about 0.25 to about 20 moles of an S-carbamoyl silver salt stabilizer precursor per mole of said silver salt.

7. A photosensitive composition as in claim 6 also comprising a polymeric binder.

8. A photosensitive composition as in claim 6 wherein said S-carbamoyl silver salt stabilizer precursor is a compound represented by the formula:

wherein R and R are each selected from the group consisting of hydrogen, alkyl containing 1 to 5 carbon atoms, phenyl, and tolyl, and R is a sulfur containing moiety which has the property of complexing with photosensitive silver halide in the presence of heat or alkali.

9. A photosensitive composition as in claim 6 wherein said S-carbamoyl silver salt stabilizer precursor is a compound represented by the formula:

wherein R is hydrogen or alkyl containing 1 to 5 carbon atoms; R is selected from the group consisting of alkyl containing 1 to 5 carbon atoms, phenyl and benzyloxy; R is amino, alkyl containing 1 to 4 carbon atoms, carboxyl, carboxyalkyl containing 2 to 5 carbon atoms, aminomethyl sulfoalkyl containing 1 to 4 carbon atoms, morpholinomethyl, or i S-ethylcarbamoyl-Z-mercaptoisobutyric acid, dicyclohexylarnine salt, tS ethylcarbamoyl-Z-mercaptoethylamine, p-toluenesulfonic acid salt, Beta-(Ethylcarbamoylthio)propanesulfonic acid guanidinium salt, and S-ethylcarbamoyl-N-acetyl-Z-mercaptoethylamine.

112. A photosensitive composition as in claim 6 which is a photographic silver halide emulsion.

References Cited I UNITED STATES PATENTS 3,647,439 3/1972 Bass 96-48 PD 3,144,336 8/1964 Herz 96-109 3,615,617 10/1971 Cologne 96-109 3,598,598 8/1971 Herz 96-109 3,365,294 1/1968 Konig 96-109 3,640,719 2/1972 Konig 96-109 RONALD H. SMITH, Primary Examiner J. L. GOODROW, Assistant Examiner US. Cl. X.R. 96-76 R mg t 6mm STArss PATENT omcs CERTIFICATE OF CORRECTION Patent No. 3,821,103 Dated July 16, 197A Zona R. Pierce, Grant M, Haist,

Jon T. Staples and David A. Pupo,

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, lines 3-6, the structure should read as follows:

36 s c R Column 7, line 23, vapor" should read -----'vapo:v."s-----a Column'g, lines 10-1 should read as follows:

stabilizer precursor 0.01% of molecular weight l-phenyl-3-pyrazolidone l g.

5 methylbenzotriazole 0.1 g.

photographic silver chloride 10 ml.

emulsion (42 milligrams of silver per ml) Column 9, Compound 1, "S- (N-ethylaminocarconyl)-L- cysteine" should read ---S- (N-ethylaminocarbonyl.)L-cysteine-----. Column 9, Compound 2, "dicylohexylamine" should read ---dicyclohexylamine---.

Column 11, Compound 20, "20" should read 2o---.

sighed and sealed this 26th day of November 1974,

QsE L) Attest:

C. MARSHALL DANN Commissioner of Patents McCOY M. GIBSON JR, 7 Attes'cing Officer