|Número de publicación||US3782949 A|
|Tipo de publicación||Concesión|
|Fecha de publicación||1 Ene 1974|
|Fecha de presentación||11 Mar 1971|
|Fecha de prioridad||11 Mar 1971|
|Número de publicación||US 3782949 A, US 3782949A, US-A-3782949, US3782949 A, US3782949A|
|Inventores||Haist G, Olivares I|
|Cesionario original||Eastman Kodak Co|
|Exportar cita||BiBTeX, EndNote, RefMan|
|Citada por (33), Clasificaciones (20)|
|Enlaces externos: USPTO, Cesión de USPTO, Espacenet|
3,782,949 PHOTOGRAPHIC ELEMENT COMPRISING A HYDROXY SUBSTITUTED ALIPHATIC CAR- BOXYLIC ACID ARYL HYDRAZIDE Ismael Adolfo Olivares, Frederic Roland Bean, and Grant Milford Haist, Rochester, N.Y., assignors to Eastman Kodak Company, Rochester, N.Y. No Drawing. Filed Mar. 11, 1971, Ser. No. 123,450 Int. Cl. G03c 1/48, 1/06 U.S. Cl. 96-76 R 8 Claims ABSTRACT OF THE DISCLOSURE Hydroxy substituted aliphatic carboxylic acid aryl hydrazides are employed as developing agents for exposed electromagnetic energy sensitive silver salts. The developing agents can be employed in developer solutions, in silver salt processing solutions, as incorporated developing agents, as a developing agent in diffusion transfer processes, and as the reducing agent in heat processing techniques.
BACKGROUND OF THE INVENTION Field of the invention This invention relates to photographic compositions and especially to novel developer compositions exhibiting improved photographic properties. The invention especially relates to photographic developer solutions, processing solutions, photographic elements and photographic emulsions containing a novel developing agent.
Description of the prior art Hydrazines and hydrazine derivatives have been employed in photographic emulsions or developers for many purposes. Mees, The Theory of the Photographic Process, 3rd edition, 1966, page 281 discloses that few developing agents of importance have been found among the hydrazines and/or their derivatives.
The use of a hydrazide in a developing solution and/ or silver halide emulsion is particularly known, however, the compounds are employed as supplemental developers or in a non-developing function, but not as principal developing agents. Trivelli et al., U.S. Pat. 2,419,975 issued May 6, 1947, for example, describes a method of improving the sensitivity of a silver halide photographic layer by incorporating therein a semicarbazide. Honig et al. U.S. Pat. 3,386,831 issued June 4, 1968, describes method of stabilizing photographic silver halide emulsions with acyl phenyl hydrazides. Whitmore U.S. Pat. 3,227,552 issued Ian. 4, 1966, discovered that a wide variety of hydrazones and hydrazides can be employed as supplemental developing agents in the process of preparing photographic direct positive color images. The developers of this invention are disclosed in Mijovic et al. British Pat. 1,157,617 as intermediates for the preparation of l-arylpyrazolid-Zi-ones. The pyrazolid-3-ones are employed as photographic silver halide developing agents.
Although some hydrazines are interesting, from a historical and theoretical point of view, as developing agents hydrazines and their derivatives have been found not to be generally useful.
There is a constant search for compounds which can develop not only exposed photographic silver halides, but additionally other photographic silver salts to visible images. The developing agents should be reasonably fast and should produce images evidencing strong image discrimination with little propensity for staining.
It is apparent, in the art, that there is a need to further improve the speed, particularly for photographic elements to be processed in the rapid machine processing systems,
, United. States Patent 3,782,949 Patented Jan. 1, 1974 and to improve the sensitometric properties of photographic developers.
It is, furthermore, desirable to find developing agents that can advantageously be employed in a variety of photographic products, for example, in photographic developer and processing solutions, as incorporated developers in photographic emulsions, in photographic products that may be processed according to the so-called dry process ing techniques, in photographic diffusion transfer products, etc.
Developing agents having such universal applications are highly unusual. A developing agent, for example, which is desirably employed in a developer solution can be useless as an incorporated developing agent, i.e. one incorporated in a photographic emulsion, since the developing agent may not be stable in the emulsion. A developing agent, as incorporated, may cause spontaneous reduction (fogging) or may be lost by oxidation. A developing agent which is incorporated in a photographic element adapted for wet processing can be generally undesirable for incorporation in a photographic element adapted for dry processing since developing agents have a tendency to induce staining unless washed out from the elements upon processing.
SUMMARY OF THE INVENTION In accordance with this invention photographic silver salt developing agents are provided which are hydroxy substituted aliphatic carboxylic acid aryl hydrazides. The developing activity of these hydrazides is unobvious and unexpected since similar hydrazides such as those of the prior art or aliphatic carboxylic acid aryl hydrazide not within the scope of this invention do not manifest any substantial developing activity.
It is, therefore, an object of this invention to provide novel photographic silver salt developing agents capable of providing increased speeds and strong image discrimination.
A further object of this invention is to provide photographic silver salt developer or processing compositions which provide desired sensitometric properties and developing action without objectionable stain.
Another object is to provide improved photographic elements and/or emulsions having a developing agent incorporated therein.
Another object of this invention is to provide developing agents which evidence low staining propensity and therefore need not be washed out of the emulsion followmg processing.
It is still a further object of the invention to provide improved photographic products, elements, developer compositions and developing processes employed in diffusion transfer systems. i
It is yet another object of this invention to provide improved photographic products, elements, developer compositions and developing processes employed in the socalled dry processing photographic systems.
DESCRIPTION OF THE PREFERRED EMBODIMENTS In accordance with the present invention, novel developing agents are provided which are hydroxy substituted aliphatic carboxylic acid aryl hydrazides. Suitable hydrazides which can be used in the practice of this invention can be represented by the general structural formula:
RiNH-NH-d-Ri wherein R is an aryl group including substituted aryl groups are exemplified by phenyl, naphthyl, alkaryl, such as, tolyl, xylyl, mesityl, ethylphenyl, propylphenyl, halide substituted phenyl such as bromophenyl, dichlorophenyl, carboxyphenyl and the like; and R is an aliphatic grouping having substituted thereon at least one hydroxy group. Aliphatic grouping should be understood to include acyclic hydrocarbyls having substituted thereon an alicyclic group. In a preferred embodiment of this invention, R can have from 1 to about 6 carbons and R, can have from 1 to about 10 carbon atoms.
In another preferred aspect of this invention the hydrazides can be represented by the general structural formula:
(II) Rr-NH-NH-C--Ra wherein R is an aryl grouping as described supra and R R and R each alone can be hydrogen, methylol, a lower alkyl such as methyl, ethyl, propyl, and the like, or R and R form a saturated ring system, with the condition that at least one of R R and R is methylol.
Illustrative examples of hydrazides which may be employed according to the invention are:
The novel developing agents of this invention are readily prepared by methods well known in the art. The developing agents, for example, can be prepared by The Method of Donovan, U.S. 2,912,461.
A significant feature and advantage of the developing agents disclosed herein is their substantially low propensity for staining, hence the developing agents need not be washed from a silver salt emulsion following processing. This feature is particularly advantageous and desirable in rapid machine processing and in photographic elements adapted for dry processing.
Another significant feature and further advantage of the hydrazides is their substantial stability when incorpo rated in a photographic element. The hydrazides neither significantly cause or induce spontaneous reduction, nor are the developing agents lost by oxidation; hence the shelf life of a photographic product is substantially extended.
A still further significant feature of the developing agents is their improved solubility over many hydrazines and hydrazides of the prior art.
As previously indicated, the novel developing agents of this invention can be suitably utilized in any of a variety of locations with respect to the photographic system. They can be employed in photographic processing and/or developing solutions, for example, in an aqueous alkaline developer composition. They can be incorporated into a layer of a photographic element such as a silver halide emulsion layer, an overcoat layer or an interlayer of a photographic element. They can be utilized in a developer composition intended for use in a diffusion transfer process or they can be utilized in one or more layers of a photographic element employed in a difiusion transfer process. Diffusion transfer processes and photographic elements in which the developing agents are useful as described, for example, in U.S. Pats. 2,352,014 of Rott 4 i, issued June 20, 1944; 2,543,181 of Land issued Feb. 27, 1951; and 3,337,342 of Green issued Aug. 22, 1967. The developing agents of this invention can also be employed in so-called high-speed diffusion transfer processes as described, for example, in U.S. Pat. 3,326,683 of Land et al. issued June 20, 1967; or in other types of diffusion transfer processes such as those described in U.S. Pats. 2,857,274 of Land et al., issued Oct. 21, 1958; 3,020,155 of Yackel et al., issued Feb. 6, 1962; 2,584,030 of Land issued Jan. 29, 1952; and 2,923,623 of Land issued Feb. 2, 1960. These patents describe typical photographic products suitable for diffusion transfer systems comprising a combination of (a) a photosensitive element which cornprises a support having thereon at least one photosensltlve silver salt emulsion layer (b) an image-receiving layer, and (c) a rupturable container containing an alkaline processing composition comprising a silver halide developing agent, and typically a silver halide solvent. The novel developing agents of this invention can be utilized in combination with photosensitive elements which are adapted for processing by the so-called dry photography (heat) development methods. No liquids, vapors or other processing aids need be employed in order to obtain a high image density or desirable image tone in the photosensitive element having incorporated therein the novel developers of this invention. Heat development processes are described, for example, in U.S. Pat. 3,457,075 of Morgan et a1. issued July 22, 1969 and 3,152,903 of Sheppard et al. issued Oct. 13, 1964. Other material which can be heat processed are described in British Pats. 1,131,- 108, issued Oct. 23, 1968, 1,161,777, issued Aug. 20, 1969, and 930,572, issued July 3, 1963, U.S. Pats. 3,301,678 of Humphlett et al., issued Jan. 31, 1967, 3,531,285 of Haist et al., issued Sept. 29, 1970, 3,392,020 of Yutzy, issued July 9, 1968, and 3,152,904 of Sorensen et al., issued Oct. 13, 1964, and German Ausligeschrift 1,003,- 578, issued Feb. 28, 1957.
The developing agents employed in the practice of this invention can be employed for developing an image in a variety of photographic emulsions. The silver halide emulsions employed can comprise silver chloride, silver bromide, silver bromoiodide, silver chlorobromoiodide or mixtures thereof. The emulsions may be coarse or fine grain and can be prepared by any of the well-known procedures, e.g., single jet emulsions, double jet emulsions, such as Lippmann emulsions, ammoniacal emulsions, thiocyanate or thioether ripened emulsions such as those described in Nietz et al. U.S. Pat. 2,222,264 issued Nov. 4, 1940; Illingsworth U.S. Pat. 3,320,069 issued May 15, 1967; and McBride U.S. Pat. 3,271,157 issued Sept. 6, 1966. Surface image emulsions may be used or internal image emulsions such as those described in Davey et al. U.S. Pat. 2,592,250 issued Apr. 8, 1952; Porter et al. U.S. Pat. 3,206,313 issued Sept. 14, 1965; Berriman U.S. Pat. 3,367,778 issued Feb. 6, 1968; and Bacon et al. U.S. Pat. 3,447,927 issued June 3, 1969. If desired, mixtures of surface and internal image emulsions may be used as described in Luckey et al. U.S. Pat. 2,996,382 issued Apr. 15, 1961. Negative type emulsions may be used or direct positive emulsions such as those described in Leermakers U.S. Pat. 2,184,013 issued Dec. 19, 1939; Kendall et al. U.S. Pat. 2,541,472 issued .Feb. 13, 1951; Berriman U.S. Pat. 3,367,778 issued Feb. 6, 1968; Schouwenaars British Pat. 723,019; Illingsworth et al. French Pat. 1,520,821; Ives U.S. Pat. 2,563,785 issued Aug. 7, 1951; Knott et al. U.S. Pat. 2,456,953 issued Dec. 21, 1968; and Land U.S. Pat. 2,861,885 issued Nov. 25, 1958. The emulsions may be regular grain emulsions such as the type described in Klein and Moisar, J. Phot. Sci., vol. 12, No. 5, September/October 1964, p. 242-251.
The developing agents or reducing agents, as commonly referred to in the art of dry photography, whi h have unexpectedly found to be suitable as a primary d p g Component in accordance with this invention can be employed in combination with any silver salt developing agent. Suitable silver halide developing agents which can be employed with the developing agents of the invention include, for example, polyhydroxybenzenes, such as hydroquinone developing agents, e.g., hydroquinone, alkyl substituted hydroquinones such as t-butyl-hydroquinone, methylhydroquinone and 2,5-dimethyl hydroquinone; catechols and pyrogallol; halogen substituted hydroquinones such as chlorohydroquinone or dichlorohydroquinone; alkoxy substituted hydroquinones such as methoxyhydroquinone or ethoxyhydroquinone; aminophenol developing agents, such as 2,4-diaminophenols, e.g., 2,4-diamino-6-methylphenol, and methylaminophenols; ascorbic acid, ascorbic acid ketals, such as those described in Green U.S. Pat. 3,337,342 issued Aug. 22, 1967; hydroxylamines such as N,N-di(2-ethoxyethyl)hydroxyamine; 3-pyrazolidone developing agents such as 1-phenyl-3-pyrazolidone, including those described in British Pat. 930,572; and acyl derivatives of p-aminophe- 1101 such as described in British Pat. 1,045,303; hydroxytetronic acid and hydroxytetronimide developing agents; reductone developing agents such as anhydrodihydropyrrolidino hexose reductone and the like.
In accordance with another embodiment of the invention, photographic developer compositions are provided comprising the silver salt developing agents described herein.
The photographic developer compositions can include ingredients commonly employed for processing photographic elements in addition to the developing agent, e.g., stabilizer compositions monobaths, activator compositions, hardener compositions and the like.
The photographic developer compositions according to the invention can contain a silver halide solvent. A variety of silver halide solvents are suitable, such as alkali metal and ammonium thiocyanates, e.g., sodium and potassium thiocyanate and ammonium thiocyanate, alkali metal thiosulfates, such as sodium thiosulfate and potassium thiosulfate, thiourea compounds, and the like.
The developing agents of the invention can be employed in processing compositions in any form suitable for developing an exposed photographic element. For example, at least one developing agent of this invention can be employed alone or with one or more auxiliary developing agents described herein. The developing agents can be provided as an aqueous silver halide developer solution or liquid concentrate; as a component of a solid particulate composition suitable for dissolving in a solvent such as an aqueous-solvent; as a viscous composition containing various thickening agents; as a packaged component of a kit for mixing with various processing agents or as a component of a fusible solid such as solid containing a homogeneous mixture of an alkylene oxide polymer and a developing agent of the invention said fusible solid melting above about room temperature, and the like.
A further aspect of the invention is a photographic process for developing exposed silver salt layers of a photographic element, said process comprising contacting the silver salt layer with the developing agents of this invention in the presence of an alkaline development activator. In accordance with this aspect, the invention can comprise a process of developing the exposed silver salts in a photographic silver salt layer by contacting the silver salt layer with a processing composition containing a silver halide solvent andthe novel silver halide developing agent. i
The process according to this aspect can also employ other silver halide developing agent, as described herein, as an auxiliary developing agent. The auxiliary developing agents can be located in a layer of a photographic element to be processed and/or in the silver halide processing composition. Developing action is effected upon contact of the developing components of the invention with a suitable activator.
Any alkaline developer activator can be employed to activate the developing agents of the invention in nondry processing photographic processes so long as the activators provide the desired pH. These include those commonly employed in the photographic art as development activators, such as inorganic alkali, e.g., alkali metal hydroxide including sodium hydroxide, potassium hydroxide and lithium hydroxide, alkali metal carbonate, such as sodium carbonate, sodium bicarbonate, fuming ammonia, and the like as Well as organic alkali such as organic amines and aminoalkanols, e.g., ethanol amines and aminodiethanolamine or morpholine. The concentration of development activator can vary depending on the various components of the system, the photographic emulsion employed, the desired image, and the like. A concentration is usually employed which provides a pH of at least about 8, typically from about 10 to about 14, and preferably about 11 to about 14.
In another embodiment of the invention, photosensitive elements are provided, said elements comprising a support, at least one silver salt layer and incorporated in said element, a photographic silver salt developing agent of this invention. The developing agent can be employed in a photographic silver salt emulsion layer, an overcoat layer, a layer under the emulsion layer, or virtually any of the layers contiguous to the silver salt to be developed.
The developing agents of the invention can be employed in photographic elements designed for processing in stabilization type processing. For example, they can be incorporated in one or more layers of a photographic element which is exposed, activated by contact with alkaline activator, and then contacted with a thiocyanate or thiosulfate solution, such as an ammonium thiocyanate, or they can be incorporated in the alkaline activator. Such processes are described, for example, in U.S. Pat. 3,326,- 864 of Nishio issued June 20, 1967; British Pat. 1,004,302; French Pat. 1,516,556 of Fassbender; and in an article by H. D. Russell, E. C. Yackel and I. S. Bruce in the PSA Journal, August 1950, pp. 59-62, entitled Stabilization Processing of Films and Papers.
The developing agents of this invention as described herein can be used in layers of photographic elements or processing solutions intended for use in monobath processing such as described in U.S. Pat. 2,875,048 of 'Haist et al. issued Feb. 24, 1959, and British Pat. 1,063,844 of Beavers et al. issued Mar. 30, 1967; and in web-type processing, such as described in U.S. Pat. 3,179,517 of Tregillus et al. issued Apr. 20, 1965.
The developing agents of this invention can be employed in a photographic silver salt emulsion designed for diffusion transfer processing and/or in a developer composition designed for developing and stabilizing the element. A typical developer composition is disclosed in U.S. Pat. 3,120,795 of Land et al. issued Feb. 11, 1964.
Hence, in accordance with an aspect of the invention there is accordingly provided in combination (a) a photographic element comprising a photographic silver salt layer, (b) a viscous processing composition, within a releasing means, e.g., a rupturable container, comprising:
(i) a silver halide solvent,
(ii) an alkaline development activator,
(iii) optionally, a 3-pyrazolidone developing agent, adiaminophenol developing agent or other auxiliary developing agent described herein, and
(iv) the novel developing agents of this invention, and
(c) an image receiving layer comprising development nuclei, especially palladium development nuclei, dispersed in a polymeric binder.
, Albeit the developing agents are generally located in a releasing means, the developing agents can be suitably employed in a variety of locations with regard to a diffusion transfer system. The novel developing agents can be provided in the silver salt layer or emulsion, in a layer near to the silver salt layer, in the image receiving layer containing silver precipitating nuclei or development nuclei as well as in the rupturable container.
In accordance with a typical difiusion transfer process a photographic element is exposed imagewise, the exposed silver halide is developed at a pH above 8, typically above 10 and preferably at a pH of about 12 to about 14, in the presence of the novel developers, the unexposed silver salts in the photosensitive silver salt layer is contacted with a silver halide solvent to form an imagewise distribution of a silver complex in the unexposed areas of said photographic silver salt layer; and at least part of the silver complex is transferred to an image receiver layer contiguous to the photosensitive layer, said receiver layer containing development nuclei, thereby forming a visible image on said receiver layer.
Processing conditions, time of development, and the like can vary depending on the desired image, the particular components of the described element, processing composition, and image receiver. Typically processing is carried out under normal atmospheric conditions and is completed within about 60 seconds, e.g., within about 10 seconds.
Usually the silver halide solvent will be sodium thiosulfate; however, various organic silver halide complexing agents such as those described by Haist et al., Phot. Sci. Eng, 5, 198 (1961) and in Kodak French Pat. 1,312,687 issued Nov. 12, 1962, and Belgian Pat. 606,559 of Ulrich et al. issued July 26, 1960, and similar agents can also be used.
The light-sensitive element, receiving element or processing composition can also contain toning agents such as, for example, polyvalent inorganic salts of the type described in U.S. Pat. 2,698,236 of Land issued Dec. 28, 1954, silica as described in U.S. Pat. 2,698,237 of Land issued Dec. 28, 1954, and heterocyclic mercaptans such as the mercapto azoles, e.g., mercapto diazoles, mercapto triazoles and mercapto tetrazoles.
Typically, the developing agent is provided in a viscous liquid photographic developer composition comprising (a) a silver halide solvent, and (b) the saliver halide developing agent of the invention. The viscous liquid photographic developer composition can also contain a second silver halide developing agent, as described herein, especially a 3-pyrazolidone silver halide developing agent.
A viscous liquid photographic developer composition can comprise a viscous monobath. Suitable viscous monobaths are described, for example, in the Monobath Manual, Morgan & Morgan, New York, by Grant M. Haist (1966).
Typically, a suitable developer composition according to the invention can comprise a viscous developer containing:
(a) a silver halide solvent, such as sodium thiosulfate, (b) a diaminophenol auxiliary developing agent, such as 6-methoxy 2,4 diaminophenol or 6-ethyl-2,4-diaminophenol or a 3-pyrazolidone auxiliary developing agent such as 1-phenyl-3-pyrazolidone or 1-phenyl-4,4-dimethyl-3-pyrazolidone,
(c) the developing agent of the invention,
(d) an alkaline development activator, and
(e) a thickening agent, such as a cellulose derivative, e.g., hydroxyethyl cellulose and/or carboxymethyl cellulose.
in the photographic process generally referred to as dry photography. The elements employed in dry photography are photosensitive, i.e., a latent image is formed image- Wise in the exposed areas of a silver salt layer, and thermosensitive, i.e., substantially permanent visible images of photographic sharpness and high visual contrast can be produced often within seconds through the mere application of heat. The dry photo-graphic elements are developed by heating to within a temperature range of from about C. to about 250 C. 7
Typically a dry photographic element comprises a support having thereon an oxidation-reduction image forming combination said combination comprising a silver salt, preferably an organic silver salt, and a reducing agent, and a catalyst for the oxidation-reduction image forming combination. I
In accordance with an aspect of the invention the hydrazides described herein can be employed as a reducing agent in the dry photographic element.
Other reducing agents as described herein can be mployed in combination with the hydrazides of this invention, and include, for example, the prior art silver halide developing agents and/or substituted phenols and naphthols as described in deMauriac, U.S. Ser. No. 33,964 filed May 1, 1970 now U.S. Pat. 3,672,904.
As the oxidizing agent, of the oxidizing-reduction image forming combination a silver salt of an organic acid is preferably employed. The silver salt of the organic acid should be resistant to darkening under illumination to prevent undesired deterioration of a developed image. An especially suitable class of silver salts of organic acids is the water insoluble silver salts of long-chain fatty acids which are stable to light. Typically, the silver salts include silver behenate, silver stearate, silver oleate, silver laurate, silver hydroxystearate, silver caprate, silver myristate, and silver palmitate. Other suitable oxidizing agents are silver benzoate, silver phthalazinone, silver benzotriazole, silver saccharin, silver 4'-n-octadecyloxydiphenyl-4-carboxylic acid, silver ortho-aminobenzoate, silver acetamidobenzoate, silver furoate, silver camphorate, silver pphenylbenzoate, silver phenyl acetate, silver salicylate, silver butyrate, silver terephthalate, silver phthalate, silver acetate, and silver acid phthalate. Nonsilver salts can be employed as oxidizing agents, such as zinc oxide, gold stearate, mercuric behen-ate, auric behen'ate land the like; however, silver salts are generally preferred.
Typically, a photosensitive silver salt is present in dry photographic elements in minor or catalytic amounts and in catalytic proximity to the oxidation image-forming component of the image-forming combination. A suitable concentration range of the catalyst is generally from about 0.01 to about 0.50 mole of photosensitive silver salt per mole of oxidizing agent. Suitable silver salts include photosensitive silver halides, e.g., silver chloride, silver bromide, silver bromoiodide, silver chlorobromoiodide, or mixtures thereof. The photosensitive silver halide can be coarse or fine-grain, very fine-grain emulsions being especially useful. The emulsion containing the photosensitive silver halide can be prepared by any of the well-known procedures in the photographic art, such as single-jet emulsions, double-jet emulsions, such as Lippmann emulsions, ammoniacal emulsions, thiocyanate or thioether ripened emulsions, such as those described in U.S. Pat. 2,222,264 of Nietz et al. issued Nov. 14, 1940; U.S. Pat. 3,320,069 of Illingsworth issued May 15, 19,67, and U.S. Pat. 3,271,157 of McBride issued Sept 6, 1966. Surface image silver halide emulsions can be used. If desired, mixtures of surface and internal image silver halide emulsions can be used as described in U.S. Pat. 2,996,382 of Luckey et al. issued Apr. 15, 1961. Negative type emulsions can be used. The silver halide emulsion can be a regular grain emulsion such as described in Klein and Moisar, Journal of Photographic Science, volume 12, No. 5, September- October (1964), pages 242-251.
The dry photographic elements preferably contain an activator-toning agent. Suitable activator-toning agents which can be employed include cyclic imides such as:
Phthalimide, N-hydroxyphthalimide, N-potassium phthalimide, N-mercury phthalimide, Succinimide, and t N-hydroxysuccinimide.
Other activator-toning agents can be employed in combination with or in place of the cyclic imides. Such other activator-toning agents are generally heterocyclic compounds containing at least two hetero atoms in the heterocyclic ring at least one being nitrogen. Illustrative compounds include phthalazinone, phthalic anhydride, 2- acetylphthalazinone and Z-phthalylphthalazinone. Grant, U.S. Pat. 3,080,254 issued Mar. 5, 1963, and Workman U.S. Pat. 3,446,648 issued May 27, 1969, describe suitable activator-toning agents.
Activator-toning agents are suitably employed at a concentration of about 0.10 mole to about 1.05 moles per mole of oxidizing agent, however, lower and higher concentrations can be employed.
This invention can be further illustrated by the following examples of preferred embodiments thereof, although it will be understood that these examples are included merely for illustrating this invention.
EXAMPLE 1 Strips of a fine grain silver bromoiodide emulsion are exposed behind a step wedge to produce a sensitometric exposure and developed at 20 C. for a series of times in the following developer composition:
Developing agent 0.02 Sodium sulfite 0.2 Trisodium phosphate 0.2 Water to 1 liter.
The pH is adjusted to 11.5 with acetic acid. The developing agents employed are:
(1) Phenylhydrazine (2) Formyl-B-phenylhydrazide 3 2,2bis (hydroxymethyl propionyl-B-phenylhydrazide (4) 2,2,2-tris(hydroxymethyl)acetyl-B-phenylhydrazide (5) 3-hydroxypivalyl-/3-phenylhydrazide The activity of the developer is measured in terms of the time required to obtain a normal degree of development, namely, a density of 1.5 on the fourth step of the sensitometric strip. The corresponding density of the unexposed area (fog) is also read. The results are entered in Table I.
TAB LE I Developing Time Image Fog agent (min.) density density EXAMPLE 2 Twenty mg. samples of the developing agents described below are placed in two sets of ml. beakers. To one set is added 1 ml. each of a 4% sodium hydroxide solution; to the other set is added 1 ml. each of a solution comprising 4% sodium hydroxide and 6% sodium sulfite. Each solution is absorbed into a 1 /2 x 2 inch strips of chromatographic paper. The strips are placed in a museum jar over water for 24 hours at room temperature. The strips are dried and the densities read to neutral transmitted light on a densitometer. The density of an untreated paper base is subtracted. to give net stain density. The results are summarized in Table II.
The low staining propensity of the developers of this invention is evident in the low density shown by this test.
TAB LE II Density to transmitted light Developing agent No sulfite With sulfite Hydroquinone.-- 1. 0. 34 1 0. 08 0.02 2 0. 24 0. 08 3"--- 0.09 0.03 2, 4-diarninophenol... 3. 82 2. 75
Nora-1 =2, 2-bis (hydroxymethybpropilom l-B-pheny 1h drazide; 2 2, 2, Z-tris (hydroxymethyl) acetyl-fi-phenylh'g, drazide; 3 =3-hy droxypivalyl-B-phenylhy drazide.
EXAMPLE 3.USE IN DRY PROCESSING SYSTEMS A dispersion is prepared by mixing the following components:
G. Silver behenate 23.3 Behenic acid 26.0 Polyvinyl butyral 1.25 Sodium bromide 1.31
Acetone-toluene 1:1 parts by volume), 500 ml.
The mixture is ball milled for 18 hours. Phthalazinone is then incorporated as an activator-toner at a weight concentration of about /2 that of the silver behenate. Hydrazides of the invention are incorporated in the mixture from alcohol-acetone solution. The concentration in weight is approximately the weight of the silver behenate. The emulsions are exposed to light behind a graphic test object and processed by heating to C. Strong black images are obtained as shown in the Table III.
Similar results are also obtained when phthalimide is employed as the activator-toner.
In the absence of an activator-toner, satisfactory images were obtained although the tone was less neutral.
EXAMPLE 4.INCORPORATION IN EMULSION Compound 3 of Example 1 is added at a concentration of 4.76 grams per gram of silver to a gelatin silver chloride emulsion. In a similar preparation 4.76 grams of 3-S- thi-uronium-l-methyl propanesulfonate is also added. The emulsions are processed by immersion in a sodium hydroxide solution. High density and low stain levels are obtained in the sodium hydroxide activators. It is not necessary to wash these strips to prevent stain formation as contrasted to the hydroquinone control which shows strong stain formation unless washed vigorously. The emulsions subjected to incubation for 14 days at F. and 35% relative humidity showed no loss in activity or a propensity for increase in fogging.
EXAMPLE 5 Developer formulations are prepared in the same manner as in Example 1, substituting the developers as summarized in Table III for those employed in Example 1.
Strips of a fine grain silver bromoiodide emulsion are processed in the same manner as in Example 1. The results are summanzed in Table IV.
The concentrations of the developing agents employed in accordance with the invention can vary over wide ranges depending upon the particular photographic and physical variables of the photographic system. Typical of the variable which effect the concentration of the developing agents are the location in the photographic element, the developer composition, the desired image, etc. Suitable concentrations are also dependent on processing conditions, addenda present in the photographic element to be processed and/or in the processing compositions. Suitable optimum concentrations can be easily determined by those skilled in the art through routine experimentation. Typically, when a developing agent described herein is incorporated in a photographic element, the concentration can vary from about 0.25 to about moles of developing agent per mole of silver present in the photographic element. A more preferred range is from about 1 to about 10 moles per mole of silver present. When a developing agent as described is employed in a composition for processing of a photographic element, the total concentration of developing agents can vary from about 1 to about 100 g./l. and preferably from about 2 to 20 ./l. g As employed in a dry photographic element the hydrazides of this invention can be present in an amount of from about 0.05 to about 3 moles per mole of oxidant and referably from about 0.25 to 2.0 moles per mole of oxidant.
The particular time required for developing the photographic elements described herein can vary over a wide range such as from about a few seconds up to an hour or more, depending on the photographic element utilized, the desired image, the various addenda employed, etc. The optimum developing time can be obtained by routine experimentation.
Silver precipitating or development nuclei or agents which can be employed in diffusion transfer systems as described can be physical development nuclei or chemical precipitants including: (a) heavy metals in colloidal form and salts of these metals, (b) salts of amines which form silver salts and/or (c) non-difiusion polymeric materials with functional groups capable of combining with the silver amine. Suitable silver precipitating agents and/or nuclei within the above classes include metal sulfides, selenides, polysulfides, polyselenides, thiourea derivatives, stannous halides, silver, gold, platinum, palladium, and mercury, colloidal silver and similar agents disclosed, for example, in U.S. Pat. 3,020,155 of Yackel et al. issued Feb. 6, 1962. A wide range of concentrations of the silver precipitating agents and nuclei can be employed. The concentration of silver precipitant or nuclei in the receiving layer or receiving sheet must be at least sufficient to ensure a positive and sufiicient removal of undeveloped silver salt from the light-sensitive layer to be processed. Usually, the concentration of developing agent described is about 3 to about 320 milligrams per square foot of the layer containing the precipitants or nuclei.
The silver halide emulsions employed with the developers of this invention may be unwashed or washed to remove soluble salts. In the latter case the soluble salts may be removed by chill-setting and leaching or the emulsion may be coagulation washed, e.g. by the procedures described in Hewitson et al. U.S. Pat. 2,618,556 issued Nov. 18, 1952; Yutzy et al. U.S. Pat. 2,614,928 issued Oct. 21, 1952; Yackel U.S. Pat. 2,565,418 issued Aug. 21, 1951; Hart et al. U.S. Pat. 3,241,969 issued Mar. 22, 1966; and Waller et al. U.S. Pat. 2,489,341 issued Nov. 29, 1949.
The emulsions employed with the developing agents of this invention may be sensitized with chemical sensitizers, such as with reducing agents; sulfur, selenium or tellurium compounds; gold platinum or palladium compounds; or combinations of these. Suitable procedures are described in Sheppard et al. U.S. Pat. 1,623,499 issued Apr. 5, 1927; Waller et al. U.S. Pat. 2,399,083 issued Apr. 23, 1946; McVeigh U.S. Pat. 3,297,447 issued Jan. 10, 1967; and Dunn U.S. Pat. 3,297,446 issued Jan. 10, 1967.
Development modifiers can be employed in combination with the silver halide emulsions as described in this invention. Typical development modifiers include polyalkylene glycols, cationic surface active agents and thiocthers or combinations of these as described in Piper U.S. Pat. 2,886,437 issued May 12, 1959; Dann et al. U.S. Pat. 3,046,134 issued July 24, 1961; Carroll et al. U.S. Pat. 2,944,900 issued July 12, 1960; and Goffe U.S. Pat. 3,294,540 issued Dec. 27, 1966.
The silver halide emulsions used in the practice of this invention can be protected against the production of fog and can be stabilized against loss of sensitvity during keeping. Suitable antifoggants and stabilizers each used alone or in combination include thiazolium salts described in Brooker et al. U.S. Pat. 2,131,038 issued Sept. 27, 1938, and Allen et al. U.S. Pat. 2,694,716 issued Nov. 16, 1954; the azaindenes described in Piper U.S. Pat. 2,886,437 issued May 12, 1959, and Heimbach et al. U.S. Pat. 2,444,605 issued July 6, 1948; the mercury salts as described in Allen et al. U.S. Pat. 2,728,663 issued Dec. 27, 1955; the urazoles described in Anderson et al. U.S. Pat. 3,287,135 issued Nov. 22, 1966; the sulfocatechols described in Kennard et al. U.S. Pat. 3,236,652 issued Feb. 22, 1966; the oximes described in Carroll et al. British Pat. 623,448; nitron; nitroindazoles; the mercaptotetrazoles described in Kendall et al. U.S. Pat. 2,403,927 issued July 16, 1946, Kennard et al. U.S. Pat. 3,266,897 issued Aug. 16, 1968, and Luckey et al. U.S. Pat. 3,397,987 issued Aug. 20, 1968; the polyvalent metal salts described in Jones U.S. Pat. 2,839,405 issued July 17, 1958; the thiuronium salts described in Herz et al. U.S. Pat. 3,200,- 839 issued Nov. 30, 1965; the palladium, platinum and gold salts described in Trivelli et al. U.S. Pat. 2,566,263 issued Aug. 28, 1951, and Yutzy et al. U.S. Pat. 2,597,915 issued May 27, 1952.
The photographic and other hardenable layers used in the practice of this invention can be hardened by various organic or inorganic hardeners, alone or in combination, such as the aldehydes, and blocked aldehydes, ketones, carboxylic and carbonic acid derivatives, sulfonate esters sulfonyl halides and vinyl sulfonyl ethers, active halogen compounds, epoxy compounds, aziridines, active olefins, isocyanates, carboiimides, mixed function hardeners and polymeric hardeners such as oxidized polysaccharides like dialdehyde starch and oxyguargum and the like.
The photographic emulsions and elements described in the practice of this invention can contain various colloids alone or in combination as vehicles, binding agent and various layers. Suitable hydrophilic materials include both 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(vinylpyrrolidone), acrylamide polymers and the like.
The described 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 latex form and particularly those which increase the dimensional stability of the photographic materials. Suitable synthetic polymers include those described, for example, in Nottorf U.S. Pat. 3,142,568 issued July 28, 1964; White U.S. Pat. 3,193,386 issued July 6, 1965; Houck et al. U.S. Pat. 3,062,674 issued Nov. 6, 1962; Houck et al. U.S. Pat. 3,220,844 issued Nov. 30, 1965; Ream et al. U.S. Pat. 3,287,289 issued Nov. 22, 1966; and Dykstra U.S. Pat. 3,411,911 issued Nov. 19, 1968; particularly eifective are those water-insoluble polymers of alkyl acrylates and methacrylates, acrylc acid, sulfoalkyl acrylates or methacrylates those which have cross-linking sites which facilitate hardening or curing, those having recurring sulfobetaine units as described in Dykstra Canadian Pat. 774,054.
The photographic elements and emulsions used with this invention may contain antistatic or conducting layers, such layers may comprise soluble salts, e.g., chlorides, nitrates, etc., evaporated metal layers, ionic polymers such as those described in Minsk U.S. Pat. 2,861,056 issued Nov. 18, 1958 and Sterman et al. U.S. Pat. 3,206,312 issued Sept. 14, 1965, or insoluble inorganic salts such as those described in Trevoy U.S. Pat. 3,428,451 issued Feb. 18, 1969.
The photographic layers and other layers of a photographic element employed in the practice of this 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 resinous 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 carbon atoms such as polyethylene, polypropylene, ethylenebutene copolymers and the like.
The photographic layers employed in the practice of this invention can contain plasticizers and lubricants such as polyalcohols, e.g., glycerin and diols of the type described in Milton et al. U.S. Pat. 2,960,404 issued Nov. 1, 1966; fatty acids or esters such as those described in Robins U.S. Pat. 2,588,765 issued Mar. 11, 1952 and Duane U.S. Pat. 3,121,060 issued Feb. 11, 1964; and silicone resins such as those described in Du Pont British Pat. 955,061.
The photographic elements employed in the practice of this invention may contain matting agents such as starch, titanium dioxide, zinc oxide, silica, polymeric beads including beads of the type described in Jelly et a1. U.S. Pat. 2,992,101 issued July 11, 1961, and Lynn U.S. Pat. 2,701,245 issued Feb. 1, 1955. I
The photographic elements and emulsions used in this invention may contain brightening agents including stilbenes, triazines, oxazoles and coumarin brightening agents. Water soluble brightening agents may be used such as those described in Albers et al. German Pat. 972,067 and McFall et al. U.S. Pat. 2,933,390 issued Apr. 19, 1960, or dispersion of brighteners may be used such as those described in Jansen German Pat. 1,150,274, Oetiker et al. U.S. Pat. 3,406,070 issued Oct. 15, 1968, and Heidke French Pat. 1,530,244.
Spectral sensitizing dyes can be used conveniently to confer additional sensitivity to light sensitive silver halide emulsions employed in the practice of this invention. For instance, additional spectral sensitization can be obtained by treating the emulsion with a solution of a sensitizing dye in an organic solvent or the dye may be added in 14 the form of a dispersion as described in Owens et al. British Pat. 1,154,781. For optimum results, the dye may either be added to the emulsion as a final step or at some earlier stage.
Sensitizing dyes useful in sensitizing such emulsions are described, for example, in Brooker et al. U.S. Pat. 2,526,- 632 issued Oct. 24, 1950; Sprague U.S. Pat. 2,503,776 issued Apr. 11, 1950; Brooker et al. U.S. Pat. 2,493,748 issued 1 an. 10, 1950; and Taber et al. U.S. Pat. 3,3 84,486 issued May 21, 1968. Spectral sensitizers which can be used include the cyanines, merocyanines, complex (trior tetranuclear) merocyanines, complex (trior tetranuclear) cyanines, holopolar cyanines, styryls, hemicyanines (e.g. enamine hemicyanines), oxonols and hemioxonols.
Dyes of the cyanine classes may contain such basic nuclei as the thiazolines, oxazolines, pyrrolines, pyridines, oxazoles, thiazoles, selenazoles and imidazoles. Such nuclei may contain alkyl, alkylene, hydroxyalkyl, sulfo alkyl, carboxyalkyl, aminoalkyl, and enamine groups and may be fused to carbocyclic or heterocyclic ring systems either unsubstituted or substituted with halogen, phenyl, alkyl, haloalkyl, cyano, or alkoxy groups. The dyes may be symmetrical or unsymmetrical and may contain alkyl, phenyl, enamine or heterocyclic substituents on the methine or polymethine chain.
The merocyanine dyes may contain the basic nuclei mentioned above as well as acid nuclei such as thiohydantoins, rhodanines, oxazolidenediones, thiazolidenediones, barbituric acids thiazolindiones, and malonitrile. These acid nuclei may be substituted with alkyl, alkylene, phenyl, carboxyalkyl, sulfoalkyl, hydroxyalkyl, alkoxyalkyl, alkylamino groups, or heterocyclic nuclei. Combinations of these dyes may be used, if desired. In addition, supersensitizing addenda which do not absorb visible light may be included, for instance, ascorbic acid derivatives, azaindenes, cadmium salts, and organic sulfonic acids as described in McFall et al. U.S. Pat. 2,933,390 issued Apr. 19, 1960, and Jones et al. US. Pat. 2,937,089 issued May 17, 1960.
The various layers including the photographic layers, employed in the practice of this invention can contain light absorbing materials and filter dyes such as those described in Sawdey U.S. Pat. 3,253,921 issued May 31, 1966; Gaspar U.S. Pat. 2,274,782 issued Mar. 3, 1942; Silberstein et al. U.S. Pat. 2,527,583 issued Oct. 31, 1950; and Van Campen U.S. Pat. 2,956,879 issued Oct. 18, 1960. If desired, the dyes can be mordanted, for example, as described in Jones et al. U.S. Pat. 3,282,699 issued Nov. 1, 1966.
The photographic layers employed in the practice of this invention may contain surfactants such as saponin; anionic compoundssuch as the alkyl aryl sulfonates described in Baldsiefen U.S. Pat. 2,600,831 issued June 17, 1962; amphoteric compounds such as those described in Ben-Ezra U.S. Pat. 3,133,816 issued May 19, 1964; and water soluble adducts of glycidol and an alkyl phenol such as those described in Olin Mathieson British Pat. 1,022,878.
The photographic layers of photographic elements used in the practice of this invention may be coated by various coating procedures including dip coating, air knife coating, curtain coating, or extrusion coating using hoppers of the type described in Beguin US. Pat. 2,681,294 issued June 15, 1954. If desired, two or more layers may be coated simultaneously by the procedures described in Russell U.S. Pat. 2,761,791 issued Sept. 4, 1956, and Wynn British Pat. 837,095. This invention also can be used for silver halide layers coated by vacuum evaporation as described in British Pat. 968,453 and LuValle et al. U.S. Pat. 3,219,451 issued Nov. 23, 1965.
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.
There is claimed:
1. In a photographic element comprising a support having thereon at least one photosensitive silver halide layer, and a silver halide developing agent, the improvement comprising a hydrazide represented by the structural formula:
Ri--NHNH Rz wherein R is an aryl group and R is an aliphatic group containing from 1 to about 6 carbon atoms and containing at least 1 hydroxy group, as the developing agent.
2. A photographic element of claim 1 wherein said developing agent is 2,2-bis(hydroxymethyl)propionyl-,6- phenylhydrazide.
3. A photographic element of claim 1 wherein said developing agent is present in said silver halide layer.
4. A photographic element of claim 1 wherein said developing agent is in a layer contiguous to said silver halide layer.
5. A photographic element of cliam 1, said element having contiguous thereto an image receiving layer.
6. In a photographic product comprising (a) a photosensitive element', said element comprising a support having thereon at least one photographic silver halide layer, (b) a releasing means containing a photographic processing solution comprising at least one developing agent, and (c) an image receiving layer, the improvement comprising employing a hydrazide represented by the formula:
wherein R is an aryl group and R is an aliphatic group containing from 1 to about 16 carbon atoms and containing at least 1 hydroxy group as the developing agent.
8. A photographic emulsion as in claim 6 wherein said binder comprises a hydrophilic colloid.
References Cited UNITED STATES PATENTS 2,419,974 5/1947 Stauifer 96-66 2,419,975 5/ 1947 Trivelli et a1. 96-95 2,563,785 8/1951 Ives 96-95 2,592,368 4/1952 Yackel 96-95 2,740,717 4/1956 Yutzy et a1. 96-95 3,227,552 1/1966 Whitmore 96-3 3,447,923 6/1969 Jaeken 96-55 NORMAN G. TORCHIN, Primary Examiner M. F. KELLEY, Assistant Examiner
|Patente citante||Fecha de presentación||Fecha de publicación||Solicitante||Título|
|US4168977 *||11 Ago 1977||25 Sep 1979||Fuji Photo Film Co., Ltd.||Silver halide photographic emulsion|
|US4207392 *||30 Oct 1978||10 Jun 1980||Eastman Kodak Company||Heat developable and stabilizable photographic materials and process|
|US4221857 *||18 Ago 1978||9 Sep 1980||Fuji Photo Film Co., Ltd.||Process for producing a high contrast photographic image|
|US4237214 *||5 Jul 1979||2 Dic 1980||Fuji Photo Film Co., Ltd.||Process for forming contrasty image|
|US4241164 *||10 Oct 1978||23 Dic 1980||Fuji Photo Film Co., Ltd.||Highly-sensitive high-contrast photographic materials|
|US4269929 *||14 Ene 1980||26 May 1981||Eastman Kodak Company||High contrast development of photographic elements|
|US4272606 *||1 Feb 1980||9 Jun 1981||Fuji Photo Film Co., Ltd.||Method of forming a high-contrast photographic image|
|US4377634 *||11 Mar 1980||22 Mar 1983||Fuji Photo Film Co., Ltd.||Method for forming high contrast photographic image|
|US4404289 *||2 Sep 1981||13 Sep 1983||Fuji Photo Film Co., Ltd.||Method for immunochemical measurement of trace components|
|US4481268 *||2 Sep 1982||6 Nov 1984||Eastman Kodak Company||Method of forming a photographic dye image|
|US4650746 *||12 Jul 1979||17 Mar 1987||Eastman Kodak Company||High contrast photographic emulsions and elements and processes for their development|
|US4684604 *||24 Abr 1986||4 Ago 1987||Eastman Kodak Company||Oxidative release of photographically useful groups from hydrazide compounds|
|US5284739 *||10 Nov 1992||8 Feb 1994||Eastman Kodak Company||Photographic silver halide color material having incorporated therein a ballasted heterocyclic-sulphonhydrazide color developing agent|
|US5409798 *||27 Ago 1992||25 Abr 1995||Canon Kabushiki Kaisha||Plate blank, process for producing printing plate from plate blank, and printing method and apparatus using plate|
|US5415981 *||4 Mar 1993||16 May 1995||Eastman Kodak Company||Photographic silver halide color materials|
|US5492803 *||6 Ene 1995||20 Feb 1996||Minnesota Mining And Manufacturing Company||Hydrazide redox-dye-releasing compounds for photothermographic elements|
|US5496695 *||6 Ene 1995||5 Mar 1996||Minnesota Mining And Manufacturing Company||Hydrazide compounds useful as co-developers for black-and-white photothermographic elements|
|US5536622 *||28 Ago 1995||16 Jul 1996||Minnesota Mining And Manufacturing Company||Hydrazide compounds useful as co-developers for black-and-white photothermographic elements|
|US5599648 *||26 Nov 1993||4 Feb 1997||Canon Kabushiki Kaisha||Surface reforming method, process for production of printing plate, printing plate and printing process|
|US5756275 *||26 Nov 1996||26 May 1998||Fuji Photo Film Co., Ltd.||Color-developing agent, silver halide photographic light-sensitive material and image-forming method|
|US5780210 *||15 Feb 1996||14 Jul 1998||Fuji Photo Film Co., Ltd.||Color developing agent, silver halide photographic light-sensitive material and image forming method|
|US5871880 *||26 Nov 1996||16 Feb 1999||Fuji Photo Film Co., Ltd.||Silver halide color photographic light-sensitive material and image-forming method|
|US5874203 *||26 Nov 1996||23 Feb 1999||Fuji Photo Film, Co., Ltd.||Color-developing agent, silver halide photographic light-sensitive material and image-forming method|
|US5889163 *||26 Nov 1996||30 Mar 1999||Fuji Photo Film Co., Ltd.||Method for producing azo dye compounds|
|US5976756 *||29 Nov 1996||2 Nov 1999||Fuji Photo Film, Co., Ltd.||Color diffusion transfer silver halide photographic materials and process for forming images|
|US6090538 *||15 Ago 1996||18 Jul 2000||Fuji Photo Film Co., Ltd.||Heat developable light-sensitive material|
|US6103458 *||31 Jul 1997||15 Ago 2000||Fuji Photo Film Co., Ltd.||Method for processing a silver halide color photographic light-sensitive material|
|US6306574||16 May 1997||23 Oct 2001||Fuji Photo Film Co., Ltd.||Photothermographic material|
|EP0762196A1 *||14 Ago 1996||12 Mar 1997||Fuji Photo Film Co., Ltd.||Heat developable light-sensitive material|
|EP0940714A2 *||20 Nov 1995||8 Sep 1999||Imation Corp.||Hydrazide compounds useful as co-developers for black-and-white thermographic elements|
|EP0940714A3 *||20 Nov 1995||15 Sep 1999||Imation Corp.||Hydrazide compounds useful as co-developers for black-and-white thermographic elements|
|WO1996021174A2 *||20 Nov 1995||11 Jul 1996||Minnesota Mining And Manufacturing Company||Hydrazide compounds useful as co-developers for black-and-white photothermographic elements|
|WO1996021174A3 *||20 Nov 1995||10 Oct 1996||Minnesota Mining & Mfg||Hydrazide compounds useful as co-developers for black-and-white photothermographic elements|
|Clasificación de EE.UU.||430/218, 430/566, 430/484, 430/249|
|Clasificación internacional||G03C1/42, G03C8/32, G03C8/36, G03C5/30, G03C5/38, G03C1/498|
|Clasificación cooperativa||G03C5/3014, G03C5/383, G03C1/42, G03C8/36, G03C1/49827|
|Clasificación europea||G03C1/42, G03C8/36, G03C5/38F, G03C1/498D, G03C5/30D|