US3785830A - Photothermographic element,composition and process - Google Patents

Photothermographic element,composition and process Download PDF

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US3785830A
US3785830A US00262907A US3785830DA US3785830A US 3785830 A US3785830 A US 3785830A US 00262907 A US00262907 A US 00262907A US 3785830D A US3785830D A US 3785830DA US 3785830 A US3785830 A US 3785830A
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thione
silver
thiazoline
photothermographic
carboxyethyl
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M Sullivan
R Cole
W Humphlett
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Eastman Kodak Co
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Eastman Kodak Co
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/494—Silver salt compositions other than silver halide emulsions; Photothermographic systems ; Thermographic systems using noble metal compounds
    • G03C1/498—Photothermographic systems, e.g. dry silver
    • G03C1/49809—Organic silver compounds
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
    • Y10S430/133—Binder-free emulsion

Definitions

  • a photothermographic element comprising a support having thereon (a) a reducing agent, (b) a silver salt of a thione compound, the thione compound being represented by the formula:
  • the photothermographic element can, but need not, contain a binder for the described components.
  • Other addenda employed in photothermographic materials can be employed with the photothermographic element 31 Claims, No Drawings PHOTOTHERMOGRAPHIC ELEMENT, COMPOSITION AND PROCESS BACKGROUND OF THE INVENTION 1.
  • This invention relates to photothermographic elements, compositions and processes for developing an image with processing with heat which can provide transparency in non-image areas.
  • photothermographic elements suitable for processing with heat containing a combination of certain reducing agents and thione complexes of silver with certain compounds which provide in the absence of image stabilizer or stabilizer precursor a stable image which is transparent in non-image areas.
  • photothermographic compositions having the described properties. It further relates to a process for developing the described image in the absence of processing solutions.
  • image stabilizer or image stabilizer precursor in the photothermographic element or composition.
  • This image stabilizer or stabilizer precursor in most instances, provides a stable complex with one or more of the components of the photothermographic material, but increases the cost of the photothermographic material.
  • thione compounds have been used in photosensitive materials for different purposes.
  • silver complexes of thione compounds have been employed in photosensitive materials as a source of silver for physical development in solution processing such as described in Belgian Pat. No. 739,708 issued Dec. 15, 1969.
  • They have also been used with silver dye complexes as described, for example, in Belgian Pat. 765,452 issued May 28, 1971. They have been used for other purposes also such as described in East German Pat. No.
  • Photothermographic components have been combined in a polymeric binder and coated on a suitable support. It has surprisingly been found that with the photothermographic materials of the invention that such a binding agent can be eliminated. This is demonstrated in following Example 24.
  • a photothermographic element and/or composition comprising (a) a reducing agent, typically a polyhydroxybenzene reducing agent, (b) a silver salt of a thione compound, the thione compound being represented by the formula:
  • n 1 to 10, typically 1 to 3
  • R represents atoms completing a 5 member heterocyclic nucleus, such as a thiazoline nucleus
  • Z is alkylene, such as alkylene containing 1 to 10 carbon atoms
  • a photosensitive component consisting essentially of photosensitive silver halide, in the absence of an image stabilizer or stabilizer precursor, and, if desired, in the absence of a binder.
  • a 5 member heterocyclic nucleus and alkylene as described include a 5 member heterocyclic nucleus and/or alkylene containing substituent groups which do not adversely affect the desired properties of the photothermographic element, such as alkyl containing l to 3 carbon atoms, e.g., methyl, ethyl or propyl, or phenyl.
  • alkylene are methylene (--CH,-), ethylene (--CH,CH,-), propylene
  • reducing agents can be employed in the described photothermographic materials of the invention.
  • These are typically silver halide developing agents and include, for example, polyhydroxybenzenes such as hydroquinone developing agents including, for instance, hydroquinone, alkyl substituted hydroquinones, exemplified by tertiary butyl hydroquinone, methyl hydroquinone, 2,5-dimethyl hydroquinone and 2,6-di-methyl hydroquinone; catechols and pyrogallol; halosubstituted hydroquinones such as chlorohydroquinone or dichlorohydroquinone; alkoxy substituted hydroquinones such as methoxy hydroquinone or ethoxy hydroquinone and the like.
  • hydroquinone developing agents including, for instance, hydroquinone, alkyl substituted hydroquinones, exemplified by tertiary butyl hydroquinone, methyl hydroquinone, 2,5-dimethyl hydroquinone and 2,6-
  • reducing agents which can be employed include reductone developing agents such as anhydro dihydro piperidino hexose reductone; hydroxy tetronic acid reducing agents and hydroxy tetronimide developing agents; 3-pyrazolidone developing agents such as l-phenyl-S-pyrazolidone and 4-methyl- 4-hydroxymethyl-l-phenyl-3-pyrazolidone and those described in British Pat. 930,572 published July 3, 1963; certain hydroxyl amine developing agents; ascorbic acid developing agents such as ascorbic acid, ascorbic acid ketals, and other ascorbic acid derivatives; phenylenediamine developing agents; certain aminophenol developing agents and the like. Combinations of reducing agents can also be employed.
  • a suitable reducing agent is one which provides a developed image within about 90 seconds at a temperature of about 100 to 250C upon heating the photothermographic element containing the reducing agent.
  • a silver salt of a thione compound is also employed in the photothermographic materials of the invention.
  • the silver salt of the thione can be prepared in situ in the photothermographic materials by combining a source of silver, such as silver trifluoroacetate, with the thione compound in the composition.
  • the thione compound is a compound represented by the formula:
  • An especially suitable thione compound is a thiazoline-2-thione represented by the formula:
  • Another suitable thione compound is an imidazoline- 2-thione represented by the formula:
  • n is l to l0, typically 1 to 3;
  • Z is alkylene containing l to 4 carbon atoms, typically methylene;
  • R is alkyl, typically alkyl containing 1 to 3 carbon atoms, such as methyl, ethyl or propyl, aryl containing 6 to 10 carbon atoms, such as phenyl, or a carboxyalkyl, such as carboxyethyl and carboxymethyl',
  • R and R are each selected from the group consisting of hydrogen, alkyl containing 1 to 4 carbon atoms, such as methyl, ethyl and propyl, aryl containing 6 to 10 carbon atoms, such as phenyl or tolyl, or R and R taken together are atoms completing a benzo group.
  • a further suitable thione compound is an oxazoline- 2-thione represented by the formula:
  • n is l to 10, typically 1 to 3; Z is as described; R and R are each selected from the group consisting of hydrogen, alkyl containing 1 to 4 carbon atoms, such as methyl, ethyl and propyl, aryl containing 6 to 10 carbon atoms, such as phenyl or tolyl, or R and R taken together are atoms completing a benzo group.
  • Suitable thione compounds within the described formulas include:
  • the described thione compounds can be prepared employing processes known in the art.
  • the described silver complexes of the thione compounds can be prepared in situ, as described, or the silver complexes can be isolated.
  • the described 4-thiazoline-2-thiones for instance, can be prepared from amino acids. Preparation of the described thione compounds can be carried out employing procedures described, for example, in an article of R. W. Lamon and W. J. Humphlett, Journal of Heterocyclic Chemistry, Volume 4, pages 6056- 09, 1967.
  • 4-thiazoline-2-thiones bearing a carboxy alkyl group in the three position can, for instance, be prepared by treating a dithiocarbamic acid derived from an amino acid and carbon disulfide with an alpha halogenated ketone.
  • a dithiocarbamic acid derived from an amino acid and carbon disulfide with an alpha halogenated ketone.
  • the use of methyl alcohol as a solvent can improve the solubility of the reactants.
  • the photothermographic materials of the invention contain photosensitive silver halide as a photosensitive component.
  • An advantage of the photothermographic materials is that the concentration of photosensitive silver halide which is needed can be very low compared to photographic materials which contain photographic silver halide in the absence of other of the photothermographic components of the invention.
  • the concentration of photosensitive silver halide which is suitable in a photothermographic composition of the invention can be about 0.0025 to about 0.3 moles of photosensitive silver halide pre mole of silver as the described complex.
  • the concentration of photosensitive silver halide is typically about 0.02 X 10 to about 0.12 X 10 moles of silver halide per square foot of support.
  • Suitable photosensitive silver halides include, for example, silver chloride, silver bromide, silver bromoiodide, silver chlorobromoiodide, or mixtures thereof.
  • silver iodide is also included as a photosensitive silver halide.
  • the photosensitive silver halide can be prepared in situ in the photothermographic material, this is not necessary according to the invention.
  • the photosensitive silver halide can be coarse or fine-grain, very fine-grain photosensitive silver halide being especially useful.
  • the photosensitive silver halide can be prepared by any of the well-known procedures employed in the photographic art.
  • the silver halide can be prepared, for example, employing single-jet preparation techniques, double-jet preparation techniques, such as techniques employed in preparing Lippmann emulsions and the like.
  • Surface image silver 1 halide materials can be used. If desired, mixtures of surface and internal image silver halide materials can be used. Negative type silver halide is typically employed.
  • the silver halide materials can be regular grain such as described in Klein and Moisar, Journal of Photographic Science, Volume 12, No. 5, September-October (1964), pages 242-25l.
  • the photosensitive silver halide can be chemically sensitized employing techniques known in the photographic arts.
  • one suitable procedure includes preparation of the silver salt of the described thione compound in situ with the photosensitive silver halide. It is desirable to avoid preparation of the silver salt in the presence of compounds which could cause undesired reduction.
  • the preparation of the silver saltin situ can typically include mixing of a source of silver, such as silver trifluoroacetate, with the thione compound as described in following Example 1.
  • a binder is not essential with the photothermographic materials described, a binder can be employed, if desired.
  • the binders which can be employed with the described photothermographic materials include various colloids employed alone or in combination as vehicles and/or binding agents which do not adversely affect the desired photothermographic properties of the described compositions and in various layers of a photothermographic element. Suitable materials can be hydrophilic or hydrophobic.
  • the binders which are suitable are transparent or translucent and 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.
  • 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 photothermographic materials.
  • Suitable binders include polymers such as water insoluble polymers of alkyl acrylates and methacrylates, acrylic acid, sulfoalkyl acrylates or methacrylates and those which have cross-linking sites which facilitate hardening or curing as well as those having recurring sulfobetaine units.
  • Especially suitable binding agents include high molecular weight materials and resins such as poly(vinyl butyral), cellulose acetate butyrate, poly(methyl methacrylate), poly(vinyl-pyrrolidone), ethyl cellulose, poly(styrene), poly(vinyl-chloride), chlorinated rubber, poly(isobutylene), butadienestyrene copolymers, vinyl chloride-vinyl acetate copolymers, copolymers of vinyl acetate, vinyl chloride and maleic acid, poly(vinyl alcohol), and high molecular weight ethylene oxide polymers.
  • One test for a suitable binder or vehicle is set out in following Example 1.
  • one embodiment of the invention is a photothermographic element comprising a support having thereon (a) a reducing agent, as described, (b) a silver salt of a thione compound, the thione compgmdbeing represented by the formula:
  • n is l to 10
  • R represents atoms completing a 5 member heterocyclic nucleus, typically a thiazoline- 2-thione nucleus
  • Z is alkylene, such as alkylene containing l to 10 carbon atoms, as described, (c) a photosensitive component consisting essentially of photosensitive silver halide, and (d) a binder, in the absence of an image stabilizer or stabilizer precursor.
  • the photothermographic layers and other layers of a photothermographic 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 resinous materials, as well as glass, paper, metal and the like.
  • 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, ethylene-butene copolymers and the like.
  • Hardenable layers of a photothermographic element can be hardened by various organic or inorganic hardeners alone or in combination, such as aldehydes, ketones, and the like which do not adversely affect the sensitometric properties of the photothermographic materials. Hardeners which cause adverse reduction of the described composition should be avoided.
  • the photothermographic elements and materials according to the invention can contain addenda commonly employed in photothermographic elements, such as antistatic and/or conducting layers, plasticizers and/or lubricants, surfactants, matting agents, brightening agents, light-absorbing materials, filter dyes, antihalation dyes and absorbing dyes, and the like.
  • addenda commonly employed in photothermographic elements such as antistatic and/or conducting layers, plasticizers and/or lubricants, surfactants, matting agents, brightening agents, light-absorbing materials, filter dyes, antihalation dyes and absorbing dyes, and the like.
  • the various components of the photothermographic materials of the invention can be added from water solutions or suitable organic solvent solutions can be used.
  • the components can be added using various procedures known in the photographic art.
  • the photothermographic layer and/or other layers of a photothermographic element according to the invention can be coated by various coating procedures including dip coating, airknife coating, curtain coating or extrusion coating using hoppers of the type described in U.S. Pat. No. 2,681,294 of Beguin, issued June 15, 1954. If desired, two or more layers can be coated simultaneously by procedures known in the art.
  • a photothermographic element according to the invention can comprise a support having thereon (a) about 0.2 X 10 to about 1.0 X 10" moles of said reducing agent, (b) about 0.23 X 10 to about 2 X 10 moles of silver as the described complex and (c) about 0.02 X 10 to about 0.12 X 10' moles of the described photosensitive silver halide per square foot of support.
  • An optimum concentration of each component will depend upon the particular components, the desired image, processing temperature and the like.
  • An especially suitable embodiment of the invention is a photothermographic element comprising a support having thereon (a) a hydroquinone reducing agent, (b) a silver salt selected from the group consisting of silver salts of 3-carboxymethyl-4-methyl-4-thiazoline-2- thione, 3-( Z-carboxyethyl)-4-hydroxymethyl-4- thiazoline-Z-thione, 3-(2-carboxyethyl)-benzothiazoline-2-thione, 3-(2-carboxyethyl)-4-methyl-4- thiazoline-2-thione, and combinations thereof (0) silver iodide, and, if desired, (d) a gelatino binder, in the absence of an image stabilizer or stabilizer precursor.
  • an agent sometimes referred to as an activator toning agent, can be employed with the photothermographic materials of the invention to provide an increase in density at certain processing temperatures.
  • Suitable toning agents also known as activator-toning agents, include cyclic imide toning agents such as phthalimide, N-hydroxyphthalimide, succinimide, and N-hydroxy succinimide, and the like. These are described, for instance, in Belgian Pat. No. 766,590, issued June 15, 1971. Sulfolane in some instances can provide improved results in the described photothermographic compositions.
  • Some photothermographic elements and compositions described according to the invention do not need a toning agent.
  • one source of silver ion can be a silver salt of an organic acid can be employed in the described photothermographic materials.
  • the silver salt of the organic acid should be resistant to darkening under illumination to prevent undesired deterioration of the developed image.
  • a silver salt of an organic acid is employed, transparency in the non-image areas of the photothermographic element is often not observed. Therefore, it is often advantageous to avoid the use of silver salts of organic acids.
  • suitable silver salts include silver behenate, silver stearate, silver oleate, silver laurate, silver hydroxy stearate, silver caprate, silver myristate, and/or silver palmitate.
  • Other silver compounds which can be employed in the described photothermographic materials include, for instance, silver benzoate, silver phthalazinone, silver benzotriazole, silver saccharin, and the like. If desired, oxidizing agents which are not silver salts can be employed in the described photothermographic materials.
  • Spectral sensitizing dyes can be used conveniently to confer additional sensitivity to the light sensitive silver halide employed according to the invention.
  • additional spectral sensitization can be obtained by treating the silver halide with a solution of a sensitizing dye in an organic solvent or the dye can be added in the form of a dispersion.
  • Spectral sensitizers which can be used include the cyanines, merocyanines, complex(trinuclear or tetranuclear) merocyanines, complex(trinuclear or tetranuclear) cyanines, holopolar cyanines, styryls, hemicyanines, such as enamines, oxonols, and hemioxonols.
  • a visible image on a photothermographic element according to the invention can be produced after imagewise exposure within a short time by merely moderately overall heating the photothermographic element.
  • a visible image on a photothermographic element according to the invention can typically be produced within a few seconds, e.g., about 1 to about 60 seconds after exposure by heating the element to about C. to about 250C., typically about C. to about C.
  • the time of heating is less than about 20 seconds, such as about 2 to 5 seconds at a temperature of about 180C.
  • Optimum time of heating and optimum temperature of heating can be determined employing test procedures well known in the art.
  • One embodiment of the invention accordingly is a method of developing and stabilizing an image in an exposed photothermographic element comprising a support having thereon (a) a reducing agent, as described, (b) a silver salt of a thione compound, also as described, (c) a photosensitive component consisting essentially of photosensitive silver halide, and, if desired, (d) a binder, in the absence of an image stabilizer or stabilizer'precursor, comprising heating the photothermographic element to about 100C. to about 250C.
  • Heating of the photothermographic element can be carried out employing various heating means. These include any suitable means which provides the desired temperature within the desired time, such as a hot metal block, heated roller, plate or the like.
  • Processing is usually carried out under ambient comditions of pressure and humidity. Pressures and humidity outside normal atmospheric conditions can be employed if desired, however, normal atmospheric conditions are preferred.
  • Various exposure means can be employed for providing a latent image in the described photothermographic materials. While the photothermographic materials are typically sensitive to the ultraviolet and blue regions of the spectrum, various exposure means can be employed for providing exposure not only in this range of sensitivity but other ranges of the spectrum. Typically, the photothermographic element is exposed employing a visible light source.
  • the pH of a photothermographic composition employed according to the invention can vary. In an aqueous formulation it is typically less than about 7, such as about 2 to about 6.
  • a photothermographic element is prepared as follows:
  • a coating formulation is prepared by mixing the following components:
  • composition A The coating formulation, which is designated as composition A, is coated at 25C at a wet coating thickness of 0.004 inch on a polyethylene coated paper support.
  • concentration of silver bromide is about 0.04 X 10 moles of silver bromide per square foot of support.
  • the resulting photothermographic element after drying the coating, is exposed imagewise to a tungsten light source through a step tablet for seconds. Processing is carried out by contacting the photothermographic e1- ement with a heated metal plate at 130C. for 20 seconds.
  • a second photothermographic element is prepared in the same manner. Upon exposing and processing by overall heating for 10 seconds at 140C., a dark image is developed in each instance having an off-white background. The image developed with 20 seconds heating at C. has a maximum density of 0.58. The image developed employing 10 seconds heating at C. has a maximum density of 0.52.
  • EXAMPLE 2 This is a comparative example.
  • composition A has the following composition:
  • Hydroquinone 5 percent by weight in methanol 2.0 ml.
  • Example 1 The procedure set out in Example 1 is repeated with the exception that the coating formulation designated as composition A contains 0.1 milliliters of acetone in place of 0.1 milliliters of silver bromide dispersed in acetone. Exposure and processing are the same as in Example 1. No visible image or reduction of silver is observed. Prolonged exposure to fluorescent light of the photothermographic element produces only a slight yellow coloration.
  • Example 1 The procedure set out in Example 1 is repeated with the exception that the thiazoline-Z-thione compound is omitted from the coating composition. Reduction of silver ion is observed during coating. No satisfactory image is produced.
  • This example demonstrates the thiazoline-2-thione and not the trifluoroacetate is the silver complexing agent in the described composition.
  • polyvinyl butyral 2% by weight in 12111 parts by volume acetone-toluene-methanol 50 ml.
  • the resulting composition is combined with 30 milliliters of 1:1 parts by volume acetone-methanol.
  • the formulation is coated on a polyethylene coated paper support at a wet thickness of 0.004 inch.
  • the resulting photothermographic element after drying is exposed sensitometrically using a tungsten light source through a step tablet.
  • the exposed photothermographic element is then processed by overall heating at 130C. to C. for 90 to 15 seconds.
  • composition B The dispersion of Example before adding the hydroquinone solution is designated as composition B.
  • composition B 8 milliliters of composition B is mixed with 1.0 milliliters of 5 percent by weight hydroquinone and 1.0 milliliters of percent by weight sulfolane in acetone.
  • the resulting composition is coated on a polyethylene coated paper support as described in Example 1 and exposed sensitometrically to tungsten light through a step wedge, also as described in Example 1.
  • the resulting image is developed by overall heating the photothermographic element from 130C. to 170C. for 60 to seconds. A range of images is produced having from brown to deep purple color at the higher processing temperatures. The maximum density of the resulting image is 0.81.
  • EXAMPLE 7 8 milliliters of composition 13 as described in Example l is mixed with l milliliter of 5 percent by weight hydroquinone and 1 milliliter of 2 percent by weight succinimide in methanol. The resulting composition is coated and exposed as described in Example 1. Development of the resulting image in the photothermographic element is carried out by processing as described in Example 6. This provides images similar to those resulting from the process of Example 6. Maximum density of the resulting image is 0.71.
  • Example 8 The procedure set out in Example 7 is repeated with the exception that the l milliliter of 2 percent by weight succinimide is replaced with l milliliter of 1 percent by weight phthalimide. Results similar to those of Example 7 are produced. Maximum density of the resulting image is 0.88.
  • gelatin 4 percent by weight in water 4 ml.
  • ammonium bromide 80 mg. per milliliter of methanol 0.2 ml.
  • the formulation is dispersed with an ultrasonic probe and coated at about 38C. at a wet thickness of 0.004 inch on a polyethylene coated paper support.
  • the coating is chill set at about 4C. and air dried.
  • the resulting photothermographic element is exposed sensitometrically to tungsten light through a step tablet for 40 seconds.
  • the image is developed by overall heating the element for 10 seconds at 150C.
  • a second element prepared in the same manner is heated for 10 seconds at 170C.
  • EXAMPLE 10 Silver iodide gelatino emulsion, 3 to 6 milligrams of silver 0.2 ml. Surfactant, 0.5 percent by weight in water 0.2 ml.
  • the composition is coated on a polyethylene coated paper support at a thickness of 0.004 inches and air dried.
  • the photothermographic element resulting is exposed sensitometrically to tungsten light through a step tablet and processed by overall heating at C. to C. for 30 to 5 seconds. This produces a brown to nearly neutral tone image with the tone depending upon processing temperature. The higher processing temperatures provide more neutral tone images.
  • the background of the image is off-white. The image has a maximum density of 0.98.
  • the processed areas exhibit virtually no post processing print up.
  • Example 10 The procedure set out in Example 10 is repeated with the exception that silver iodide is replaced with silver bromide. Exposure and processing is carried out as described in Example 10 to provide a developed image having neutral tone with a maximum density of 0.51 and low contrast. The processed areas exhibit virtually no post processing print up.
  • EXAMPLE 12 The procedure set out in Example 10 is repeated with the exception that the 4-thiazoline-2-thione is replaced by 3-(3-carboxypropyl)-4-hydroxymethyl-4-thiazoline- 2-thione. Also, 4.24 grams of this thione compound is employed in place of the thione compound of Example 10. Upon exposure and processing, as described in Example 10, a developed image is produced having a maximum density and tone similar to that of the image developed according to Example 10.
  • Example 13 The procedure set out in Example 10 is repeated with the exception that the described coating composition is coated on a gel subbed polyethylene terephthalate film support. Upon exposure and processing as described in Example 10, a developed image results.
  • the film support is transparent and upon processing with heat, the emulsion layer becomes transparent in the non-image areas such that minimum transmission densities as low as 0.1 are observed.
  • Example No. Compound 20 3-(Z-carboxyethyl)-4-hydroxy-
  • Example Compound methyl-4-thiazoline-Z-thione 21 14 3-(Zwarbogyeghyl)-4-methyl-4- fi sg zzgimz g methyl 4 thiazoline- -t ione 15
  • 2- b 11 1 b l6 3-(Z-carboxyethyl)-5-phenyl-l,3,4- 2 g f z y) enzothlazolme oxadiazoline-Z-thione
  • a V 17 3-(2-carboxyethyll 5-phenyl- 5
  • EXAMPLE 24 1,3,4-thiadiazoline-Z-thione l8 ga y 1 ⁇ y This illustrates preparation of a photothermographic l3 On 19
  • Silver complexes are prepared by mixing a solution 3-(2-carboxyethyl)-4-hydroxymethyl-4-thiazoline-2- of the following thione compounds with a solution of a thione 16 g. silver salt which is either silver nitrate or silver trifluorsilver trifluoroacetate 7 g. oacetate.
  • the silver salt and thione compound are water 90ml. This is designatedasComposition D. mixed in about stoichiometric proportions.
  • Solvents which are employed are determined by the solubility The following components are mixed:
  • a solution ratio of .a thione compound to silver ion is maintained at about 2:1.
  • the resulting finally divided precipitates are isolated by filtration and either used directly in the composition described in Example 10 in place of the thione compound described in Example 10 or ball-milled for a short time before mixing with the processing composition of Example 10.
  • the resulting silver complexes are mixed with the processing composition described in Example 10 using various organic solvent mixtures before coating on the described support. Exposure and processing are carried out as described in Example 10.
  • Composition D 3.5 ml.
  • hydroquinone 5 percent by weight in methanol 2 surfactant, 0.5 percent by weight in water 0.4 ml.
  • EXAMPLE 3 3 The procedure set out in Example 5 is repeated with the exception that a concentration of about milligrams of silver as silver bromoiodide is used in place of the silver iodide.
  • a developed, stable image is provided at 170C within seconds.
  • EXAMPLE 34 The procedure set out in Example 5 is repeated with the exception that a concentration of about 10 mg. of silver as silver halide in the form of silver bromoiodide is used in place of silver iodide.
  • a spectral sensitizing dye which is 3-carboxymethyl-5-[(3-methyl-2(3H)- thiazolinylidene)-isopropylidene]rhodanine is also added to composition C at a concentration of about 50 mg. to about 2.0 grams per mole of photosensitive silver.
  • a developed stable image is provided at 170C within 15 seconds.
  • the photographic speed of the photothermographic element is about 1.5 log E faster than the photographic speed of the photothermographic element of Example 33.
  • a photothermographic element comprising a support having thereon a. a reducing agent
  • n 1 to 10;
  • Z is alkylene containing 1 to 4 carbon atoms;
  • R and R are each selected from the group consisting of hydrogen, alkyl containing 1 to 4 carbon atoms, and aryl containing 6 to 10 carbon atoms, or taken together are atoms completing a benzo group.
  • photothermographic element of claim 1 wherein said photosensitive silver halide is silver iodide.
  • a photothermographic element comprising a support having thereon a. a hydroquinone reducing agent,
  • a silver salt selected from the group consisting of silver salts of 3-carboxymethyl-4-methyl-4thiazoline-Z-thione,
  • the photothermographic element of claim 5 comprising a support having thereon per square foot of support a. about 0.25 X 10 to l X 10 moles of HQ b. about 0.25 X 10' to 2 X 10 moles of silver as said silver salt of a thiazoline-Z-thione compound, and
  • a photothermographic element comprising a support having thereon 2 a. a reducing agent b. a silver salt of a thione compound, said thione compound being represented by the formula:
  • n is l to 10; Z is alkylene containing 1 to 4 carbon atoms; R and R are each selected from the group consisting of hydrogen, alkyl containing 1 to 4 carbon atoms, and aryl containing 6 to 10 carbon atoms, or taken together are atoms completing a benzo group.
  • a photothermographic element comprising a support having thereon a. a hydroquinone reducing agent,
  • a silver salt selected from the group consisting of silver salts of 3-carboxymethyl-4-methyl-4-thiazoline-2-thione, 3-(2-carboxyethyl)-4-hydroxymethyl-4-thiazoline- 2-thione, 3-(Z-carboxyethyl)-benzothiazoline-2-thione,
  • the photothermographic element of claim 11 comprising a support having thereon per square foot of support a. about 0.25 X 10 to l X 10 moles of hydroquinone b. about 0.25 X 10 to 2 X 10' moles of silver as said silver salt of a thiazoline-Z-thione compound, and
  • a photothermographic composition comprising a. a reducing agent,
  • R -s 1 R7 wherein n is l to 10; Z is alkylene containing 1 to 4 carbon atoms, R and R are each selected from the group consisting of hydrogen, alkyl containing 1 to 4 carbon atoms, and aryl containing 6 to 10 carbon atoms, or taken together are atoms completing a benzo group.
  • a photothermographic composition comprising a. a hydroquinone reducing agent,
  • a silver salt selected from the group consisting of silver salts of 3-carboxymethyl-4-methyl-4-thiazoline-2-thione, 3-(2-carboxyethyl)-4-hydroxymethyl-4-thiazoline- 2-thione, 3-(2-carboxyethyl)-benzothiazoline-Z-thione, 3-(Z-carboxyethyl)-4-methyl-4-thiazoline-2- thione, and combinations thereof.
  • a photothermographic composition comprising a. a reducing agent, b. a silver salt of a thione compound, said compound containing the moiety wherein n is l to 10, R represents atoms completing a or 6 member heterocyclic nucleus, Z is alkylene containing l to carbon atoms,
  • a photosensitive component consisting essentially of photosensitive silver halide
  • a photothermographic composition comprising a. a hydroquinone reducing agent,
  • a silver salt selected from the group consisting of silver salts of 3-carboxymethyl-4-methyl-4-thiazoline-2-thione, 3-(2-carboxyethyl)-4-hydroxymethyl-4-thiazoline- 2-thione, 3-(2-carboxyethyl)-benzothizoline-2-thione, 3-(2-carboxyethyl)-4-methyl-4-thiazoline-2- thione, and combinations thereof
  • silver iodide in the absence of a binder and in the absence of an image stabilizer or stabilizer precursor.
  • a method of developing and stabilizing an image in a photothermographic element comprising a support having thereon a. a reducing agent,
  • n is l to 4;
  • Z is alkylene containing 1 to 4 carbon atoms, R and R are each selected from the group consisting of hydrogen, alkyl containing l to 4 carbon atoms, and aryl containing 6 to 10 carbon atoms, or taken together are atoms completing a benzo group.
  • a silver salt selected from the group consisting of silver salts of 3-carboxymethyl-4-methyl-4-thiazoline-2-thione, 3-(Z-carboxyethyl)-4-hydroxymethyl-4-thiazoline- 2-thione, 3-(2-carboxyethyl)-benzothiazoline-2-thione, 3-(2-carboxyethyl)-4-methyl-4-thizoline-Z-thione,
  • a photosensitive silver halide in the absence of an image stabilizer or stabilizer precursor, comprising heating said photothermographic element to about 100C. to about 250C. for about 1 to about 60 seconds.
  • a method of developing and stabilizing an image in a photothermographic element comprising a support having thereon a. a reducing agent b. a silver salt of a thione compound, said compound containing the moiety mula:
  • n is l to 4;
  • Z is alkylene containing 1 to 4 carbon atoms;
  • R and R are each selected from the group consisting of hydrogen, alkyl containing 1 to 4 carbon atoms, and aryl containing 6 to 10 carbon atoms, or taken together are atoms completing a benzo group.
  • the method of preparing a photographic transsilver salts of parency employing an imagewise exposed photother- 3-carboxymethyl-4-methyl-4-thiazoline-2-thione, mographic element comprising a transparent support 3-( 2-carboxyethyl)-4-hydroxymethyl-4-thiazolinehaving thereon 2-thione, a. a hydroquinone reducing agent, 3-(Z-carboxyethyl)-benzothiazoline-2-thione, b. a silver salt selected from the group consisting of 3-(2-carboxyethyl)-4-methyl-4-thiazoline-2- silver salts of thione, and combinations thereof 3-carboxymethyl-4-methyl-4-thiazoline-Z-thione,
  • 3-( 2-carboxyethyl)-4-methyl-4-thiazoline-2- 30 The method of claim 29 wherein said element thione, and combinations thereof,
  • a photosensitive silver halide a. about 0.25 X 10" to l X 10 moles of HQ in the absence of an image stabilizer or stabilizer preb. about 0.25 X l0- to 2 X 10 moles of silver as cursor, comprising heating said photothermographic said silver salt of a thiazoline-Z-thione compound, element to about 100C. to about 250C. for about 1 to and about 60 seconds.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
  • Nitrogen- Or Sulfur-Containing Heterocyclic Ring Compounds With Rings Of Six Or More Members (AREA)
  • Thiazole And Isothizaole Compounds (AREA)
  • Plural Heterocyclic Compounds (AREA)
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US3893860A (en) * 1974-07-16 1975-07-08 Eastman Kodak Co Photothermographic element and process
US4022617A (en) * 1974-07-25 1977-05-10 Eastman Kodak Company Photothermographic element, composition and process for producing a color image from leuco dye
US4105451A (en) * 1976-12-22 1978-08-08 Eastman Kodak Company Photothermographic material, composition and process
US4123274A (en) * 1977-03-16 1978-10-31 Eastman Kodak Company Heat developable imaging materials and process
US4161408A (en) * 1977-06-06 1979-07-17 Minnesota Mining And Manufacturing Company Method for the preparation of a photothermographic system
US4168980A (en) * 1977-08-19 1979-09-25 Eastman Kodak Company Heat developable photographic material and process
US4186009A (en) * 1978-05-30 1980-01-29 Eastman Kodak Company Covering power photothermographic material and process
US4201582A (en) * 1974-05-02 1980-05-06 Eastman Kodak Company Photothermographic and thermographic element, composition and process
US4235957A (en) * 1979-01-25 1980-11-25 Eastman Kodak Company Thermal silver-dye bleach element and process
US4283477A (en) * 1978-11-02 1981-08-11 Eastman Kodak Company Photothermographic material and process
US5238792A (en) * 1992-04-20 1993-08-24 Minnesota Mining And Manufacturing Company Imageable articles having dye selective interlayers
US5240809A (en) * 1992-04-20 1993-08-31 Minnesota Mining And Manufacturing Company Imageable articles having dye selective interlayers
US5262272A (en) * 1992-10-08 1993-11-16 Minnesota Mining And Manufacturing Company Dye permeable polymer interlayers
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US5891615A (en) * 1997-04-08 1999-04-06 Imation Corp. Chemical sensitization of photothermographic silver halide emulsions
US5928857A (en) * 1994-11-16 1999-07-27 Minnesota Mining And Manufacturing Company Photothermographic element with improved adherence between layers
US5939249A (en) * 1997-06-24 1999-08-17 Imation Corp. Photothermographic element with iridium and copper doped silver halide grains
US6132949A (en) * 1996-12-25 2000-10-17 Fuji Photo Film Co., Ltd. Photothermographic material
US6171707B1 (en) 1994-01-18 2001-01-09 3M Innovative Properties Company Polymeric film base having a coating layer of organic solvent based polymer with a fluorinated antistatic agent
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US20040166449A1 (en) * 2000-01-19 2004-08-26 Sekisui Chemical Co., Ltd. Polyvinyl acetal resin for heat-developable photosensitive material and heat-developable photosensitive material
US20040260020A1 (en) * 2001-09-21 2004-12-23 Yoshitaka Miyake Modified polyvinyl acetal resin
US7468241B1 (en) 2007-09-21 2008-12-23 Carestream Health, Inc. Processing latitude stabilizers for photothermographic materials
US20090081578A1 (en) * 2007-09-21 2009-03-26 Carestream Health, Inc. Method of preparing silver carboxylate soaps
US20090181332A1 (en) * 2008-01-14 2009-07-16 William Donald Ramsden Protective overcoats for thermally developable materials
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US4201582A (en) * 1974-05-02 1980-05-06 Eastman Kodak Company Photothermographic and thermographic element, composition and process
US3893860A (en) * 1974-07-16 1975-07-08 Eastman Kodak Co Photothermographic element and process
US4022617A (en) * 1974-07-25 1977-05-10 Eastman Kodak Company Photothermographic element, composition and process for producing a color image from leuco dye
US4105451A (en) * 1976-12-22 1978-08-08 Eastman Kodak Company Photothermographic material, composition and process
US4128557A (en) * 1977-03-16 1978-12-05 Eastman Kodak Company Silver salts of 1,2,4-mercaptotriazole derivatives
US4123274A (en) * 1977-03-16 1978-10-31 Eastman Kodak Company Heat developable imaging materials and process
US4161408A (en) * 1977-06-06 1979-07-17 Minnesota Mining And Manufacturing Company Method for the preparation of a photothermographic system
US4168980A (en) * 1977-08-19 1979-09-25 Eastman Kodak Company Heat developable photographic material and process
US4186009A (en) * 1978-05-30 1980-01-29 Eastman Kodak Company Covering power photothermographic material and process
US4283477A (en) * 1978-11-02 1981-08-11 Eastman Kodak Company Photothermographic material and process
US4235957A (en) * 1979-01-25 1980-11-25 Eastman Kodak Company Thermal silver-dye bleach element and process
US5238792A (en) * 1992-04-20 1993-08-24 Minnesota Mining And Manufacturing Company Imageable articles having dye selective interlayers
US5240809A (en) * 1992-04-20 1993-08-31 Minnesota Mining And Manufacturing Company Imageable articles having dye selective interlayers
US5264321A (en) * 1992-07-16 1993-11-23 Minnesota Mining And Manufacturing Company Photothermographic elements with novel layer structures
US5275927A (en) * 1992-07-16 1994-01-04 Minnesota Mining And Manufacturing Company Photothermographic articles containing novel barrier layers
US5364733A (en) * 1992-07-16 1994-11-15 Minnesota Mining And Manufacturing Company Photothermographic elements with novel layer structures, each of which contains a thermally-diffusible oxidizable leuco dye and process for producing a color image from leuco dye
US5262272A (en) * 1992-10-08 1993-11-16 Minnesota Mining And Manufacturing Company Dye permeable polymer interlayers
US5464737A (en) * 1993-04-29 1995-11-07 Minnesota Mining And Manufacturing Company Post-processing stabilizers for photothermographic articles
US6171707B1 (en) 1994-01-18 2001-01-09 3M Innovative Properties Company Polymeric film base having a coating layer of organic solvent based polymer with a fluorinated antistatic agent
US5705676A (en) * 1994-06-30 1998-01-06 Minnesota Mining And Manufacturing Company Chromogenic leuco redox-dye-releasing compounds for photothermographic elements
US5696289A (en) * 1994-06-30 1997-12-09 Minnesota Mining And Manufacturing Company Blocked leuco dyes for photothermographic elements
US5492805A (en) * 1994-06-30 1996-02-20 Minnesota Mining And Manufacturing Company Blocked leuco dyes for photothermographic elements
US5492804A (en) * 1994-06-30 1996-02-20 Minnesota Mining And Manufacturing Company Chromogenic leuco redox-dye-releasing compounds for photothermographic elements
US5928857A (en) * 1994-11-16 1999-07-27 Minnesota Mining And Manufacturing Company Photothermographic element with improved adherence between layers
US5492803A (en) * 1995-01-06 1996-02-20 Minnesota Mining And Manufacturing Company Hydrazide redox-dye-releasing compounds for photothermographic elements
US6132949A (en) * 1996-12-25 2000-10-17 Fuji Photo Film Co., Ltd. Photothermographic material
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US5939249A (en) * 1997-06-24 1999-08-17 Imation Corp. Photothermographic element with iridium and copper doped silver halide grains
US6060231A (en) * 1997-06-24 2000-05-09 Eastman Kodak Company Photothermographic element with iridium and copper doped silver halide grains
US20040166449A1 (en) * 2000-01-19 2004-08-26 Sekisui Chemical Co., Ltd. Polyvinyl acetal resin for heat-developable photosensitive material and heat-developable photosensitive material
US7176257B2 (en) 2000-01-19 2007-02-13 Sekisui Chemical Co., Ltd. Polyvinyl acetal resin for heat-developable photosensitive material and heat-developable photosensitive material
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US7622247B2 (en) 2008-01-14 2009-11-24 Carestream Health, Inc. Protective overcoats for thermally developable materials
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Also Published As

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FR2188191A1 (de) 1974-01-18
IT985421B (it) 1974-11-30
GB1427966A (en) 1976-03-10
JPS4952626A (de) 1974-05-22
DE2329170A1 (de) 1973-12-20
JPS5234451B2 (de) 1977-09-03
BE800925A (fr) 1973-12-14
FR2188191B1 (de) 1978-11-17
CA1007091A (en) 1977-03-22

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