US2598079A - High-speed photographic silver halide emulsions supersensitized with palladium salts - Google Patents

High-speed photographic silver halide emulsions supersensitized with palladium salts Download PDF

Info

Publication number
US2598079A
US2598079A US47108A US4710848A US2598079A US 2598079 A US2598079 A US 2598079A US 47108 A US47108 A US 47108A US 4710848 A US4710848 A US 4710848A US 2598079 A US2598079 A US 2598079A
Authority
US
United States
Prior art keywords
emulsion
silver halide
moles
emulsions
group
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US47108A
Other languages
English (en)
Inventor
Robert E Stauffer
William F Smith
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Eastman Kodak Co
Original Assignee
Eastman Kodak Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to BE490866D priority Critical patent/BE490866A/xx
Application filed by Eastman Kodak Co filed Critical Eastman Kodak Co
Priority to US47108A priority patent/US2598079A/en
Priority to GB22520/49A priority patent/GB659033A/en
Priority to FR1007305D priority patent/FR1007305A/fr
Priority to DEE2142A priority patent/DE964561C/de
Application granted granted Critical
Publication of US2598079A publication Critical patent/US2598079A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • 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
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
    • G03C1/08—Sensitivity-increasing substances
    • G03C1/09—Noble metals or mercury; Salts or compounds thereof; Sulfur, selenium or tellurium, or compounds thereof, e.g. for chemical sensitising

Definitions

  • FIG. 1 is a diagrammatic representation of FIG.
  • high speed photographic silver halide emulsions can be prepared by incorporating in the emulsions labile sulfur sensitizing bodies or gelatins and/or gold compounds.
  • a palladium salt can be added to them a palladium salt.
  • the emulsion can be brought tomaximum sensitivity with the gold compound and then be rendered still more sensitive with the palladium salt, or the emulsion can be brought to a sensitivity short of the maximum sensitivity attainable with the gold compound and then. be rendered more sensitive with the palladium salt.
  • the palladium salts act as sensitizers for the low intensity portion of the reciprocity curve of such emulsions sensitized with gold compounds.
  • the high-speed silver halide emulsions sensitized with at least one gold compound can be prepared by incorporating at least one gold compound in a photographic silver halide emulsionat any stage of the preparation ofthe emulsion or, when the emulsion iscomplated, e. g. just'before coating of the emulsion.
  • the gold compound is advantageously employed in a concentration equal to not more than 0.015 per cent by moles of the silver halide in the emulsion, and in the case of gelatino-silver-bromide (including the so-called bromoiodide emulsions ofwliich the majority of the halide is bromide, with a few per cent of iodide), the upper limit is advantageously 0.01 per cent by moles. Up to 0.015 percent by moles-of the silver halide in the emulsion, the-amount of, the gold compound can vary widely, as perceptible effects can be obtained with 0.0003 per cent or less.
  • Advantae sly the lower limit is about 0.001 per cent by moles of the, silver halide in the emulsion. We havefound that from 0.003 per cent to about 0.005 per cent by moles is advantageously employed in practice, especially when the gold compound is incorporated in the emulsion during the. preparation of the emulsion, i. e. especially when the emulsion is digested in thepresenceof the gold compound.
  • the gold compounds can be added to theemlllsions at any stage of thepreparation of the emulsions, i. e. before or during precipitation of the silver halides, before or during the first digestion (ripening) of the emulsion, beforeor during the second digestion of the emulsion, or the gold compounds can beadded to the emulsion J'ust beforecoating the emulsion.
  • the gold compounds are advantageously incorporated in the emulsions in the form of their solutions in a suitable solvent, e. g. water, methyl alcohol, ethyl alcohol, etc.
  • the gold compounds which we have found are most advantageously employed in preparing .the high speed emulsions are the gold halides, such as auric chloride, or complex gold halides, Such as potassium chloroaurate (KAuCli) and sodium chlorcaurate (NaAuCll).
  • gold compounds, such. as auric sulfate are practically as useful as the, gold halides.
  • Aurous, as well as auric compounds can be used.
  • Complex. gold salts such as alkali metal aurous thiosulfates, alkali metal aurous sulfites (e. g. sodium or potassium aurous thiosulfate and sodium or potassium aurous sulfite), and a complex salt formed by the interaction.
  • thiourea and auric chloride are also suitable.
  • Potassium chloroaurite, potassium bromoaurite, potassium iodoaurite, potassium auricyanide, potassium aurithiocyanate or the corresponding sodium, calcium, strontium, cadmium or gallium salts can alsobe used.
  • Pyridinotrichloro-gold, ethylenediamine-bis-trichlorogold, diethyl-monobromo-gold and diethyl gold acetone and gold complexes with sulfur compounds'such as are commonly present in gelatin, e. g. the gold thiosinamine complexes, canalso be used.
  • Sulfur sensitizers are advantageously also added to the emulsions.
  • Beneficial efiects are also obtained byadding metal or ammonium thiocyanates, e.
  • One or more sulfur sensitizer can be employed, and one or more thiocyanates selected from the group consisting of metal and ammonium t-hiocyanates can be employed in conjunction with a sulfur sensitizer other than a thiecyanate containing a cation selected from the group consisting of metal and ammonium cations.
  • the sulfur sensitizers are advantageously incorporated in the emulsions in the form of their solutions in a suitable solvent, such as water, methyl or ethyl alcohol.
  • the sulfur sensitizers can be incorporated in the emulsions at any stage of the preparation of the emulsion, e. g. during the precipitation of the silver halides, during the first digestion (ripening) or during the second digestion of the emulsion.
  • the amount can vary widely.
  • thiocyanate equal to from about 2 to about 15 per cent by moles of the silver halide in the emulsion is advantageously employed. If the thiocyanate or other sulfur sensitizer is not added until later in the preparation of the emulsion, e. g. after washing, it is advantageous to employ an amount equal to from about 0.1 to about 2.5 per cent by moles of the silver halide present in the emulsion in the case of metal and ammonium thiocyanates, and an amount equal to from about 0.006 to about 0.06 per cent by moles of the silver halide in the case of other sulfur sensitizers.
  • digest i. e. heat treat the emulsion with the gold compound with or without the sulfur sensitizer, at an appropriate temperature, e. g. at from 100 to 150 F.
  • pH of the emulsion is advantageously adjusted to the acid side of neutrality, e. g. between 5 and 7. Maintenance of the emulsion on the acid side of neutrality during coating of the emulsion is also advantageous.
  • MzPdXs and MzPdX4 wherein M represents a member selected from the group consisting of an alkali metal atom and an ammonium radical, and X represents a halogen atom selected from the group consisting of chlorine, bromine and iodine atoms.
  • Typical of such palladium salts are: ammonium chloropalladate, potassium chloropalladate, sodium chloropalladate, ammonium chloropalladite, sodium chloropalladite, potassium bromopalladate, potassium iodopalladate, etc.
  • the palladium salts are advantageously added to the emulsion just before coating the emulsion, but can be added at any time to the finished emulsions.
  • One or more of the palladium salts can be used.
  • the palladium salts are advantageously incorporated in the emulsions in the form of their solutions in a suitable solvent, e. g. water, methyl alcohol, etc.
  • the palladium salts are advantageously employed in a concentration of from 0.015 to 0.2 per cent by moles of the silver halide in the emulsion. Usually from 0.3 to 0.15 per cent by moles produces the maximum supersensitizing effect.
  • the palladium salts act to sensitize the emulsions sensitized with the gold compounds, for the low-intensity portion of the reciprocity curve. For many purposes, such as astronomical and spectroscopic photography, it is useful to have photographic emulsions showing a low reciprocity failure at low intensities. The effect of the palladium salts in this respect is apparent from the curves in the accompany drawing. Fig.
  • Fig. 2 shows reciprocity curves for the emul sions of Example 2, (with and without KzPdCls) in which log I is plotted against log It (dentitreingside) :1.
  • Crime (3. in Fig. 2 represents the emulsion without the palladium salt and curve D. represents the emulsion with palladiumisalt. It.:wil1'.be observed that .theemul- .sionj containing, the palladium salt shows distinctly lower reciprocity failure especially at the lower intensities.
  • the emulsions prepared in accordance with Our-invention canhecoated in-therusual manner on supports such as. glass, photographic film base, e. g. cellulose. acetate type, photographic paper-base, etc.
  • Sensitizing .dyes of: all types can be employed to spectrally sensitize our new emulsions, e. g.
  • any of the sensitizing oya-nine dyes any of the sensitizing merocyanine dyes v(see United States Patent 2,078,233, dated April '27, 1937, forexamplez, any of thesensitizing 'hemicyaninedyes (see United StatesIPa-tent 2,166;736, dated July 18, 1939, for example) and of thesensitizing hemioxonol dyes (see United States Patent 2,165,339, dated July 11,1939, for example), etc.
  • Our invention is directed primarily to the customarily employed photographic silver halide developing-out emulsions, e. g. silver chloride, silver chlorobromide, silver chlorobromoiodide, silver bromide and silver bromoiodide developingout emulsions.
  • a suitable gelatino-silver-halide emulsion is described, for example, by A. P. H. Trivelli and W. F. Smith, Phot. J. 79, 330 (1939).
  • Such an emulsion can be prepared as follows:
  • Solution A was kept at a temperature of 70 C. and solution .B was put in a separator-y funnel at a temperature 015172 C.
  • Solution B was allowed to run, in minutes, from the separatory funnel through a calibrated nozzle into solution A which was kept in constant motion during the precipitation of the silver halide.
  • the resulting emulsion while being kept in constant motion was ripened for 20 minutes at 70" C.
  • the emulsion was cooled as quickly as possible to C. and at this temperature, 1250 g. of washed gelatin were added to the emulsion.
  • the emulsion was stirred for 20 minutes at 45 C. in order to dissolve the gelatin.
  • the emulsion After standing overnight in a cold storage room (10 C.), the emulsion was shredded and washed. It was then melted at a temperature of 42 C. Theweight of the emulsion was brought to 31.5 kgs. by adding 500 g. of gelatin soaked in the required amount of distilled water. The emulsion was then finished at C. to the desired speed, in the presence of one or more'gold compounds and one or more sulfur sensitizers (see Examples 1 and 2).
  • M represents a member selected from the group consisting .of an alkali metal atomand an ammonium radical
  • X represents a. halogen atom selectedfrom the group consis'tingof chlorine, bromine and .iodine atoms, the concentration of said palladium salt in the. emulsion being equal to from 0.015 to 0.2% by moles of. the silver halide in the emulsion.
  • M represents a member selected from the group consisting of an alkali metal atom and an ammonium radical
  • X represents a halogen atom selected from the group consisting of chlorine, bromine and iodine atoms, the concentration of said palladium salt.- in the emulsion being equal to from 0.015 to 0.2% by moles of'the silver halidein the emulsion.
  • M represents an, alkali metal atom, said emulsion containing; asa supersensitizer; at least one palladium salt selected from those represented by 'the" followinggeneral formula:
  • M represents an alkali metal atom
  • concentration of said .gold. salt being equal to from 0.001 to0.0l% by moles of thesilver halide in the emulsion and the concentration. of said palladium salt being equal to from 0.015 to 0.2% by moles of the silver halide in the emulsion.
  • KiPdCle potassium chloropalladate
  • Ahigh speed photographic gelatino-silverhalide developing out emulsion sensitizedv with potassium chloroaurate (KAuCh) in a concentration equal to from 0.001 to 0.01% by moles of the silver halide in the emulsion, said emulsion containing, as a-supersensitizer, potassium chloropalladite" (K2PC1C14) in a concentration equal to from 0.015 to 0.2% by moles of the-silver-halide in the emulsion.
  • K2PC1C14 potassium chloropalladite
  • MIzPdXs and M2PdX/l wherein M represents a member selected from the group consisting of an alkali metal atom and an ammonium radical, and X represents a halogen atom selected from the group consisting of chlorine, bromine and iodine atoms, the concentration of said palladium salt in the emulsion being equal to from 0.015 to 0.2% by moles of the silver halide in the emulsion.
  • a high speed photographic gelatino-silverhalide developing-out emulsion sensitized with at least one gold salt selected from those represented by the following general formula:
  • M represents an alkali metal atom, in a concentration equal to from 0.001 to 0.01% by moles of the silver halide in the emulsion, and at least one thiocyanate selected from the group consisting of alkali metal and ammonium thiocyanates in a concentration equal to from 0.1 to 2.5% by moles of the silver halide in the emulsion, said emulsion containing, as a supersensitizer, at least one palladium salt selected from those represented by the following general formula:
  • M represents an alkali metal atom, the concentration of said palladium salt in the emulsion being equal to from 0.03 to 0.15%
  • K2PdCl6 potassium chloropalladate -(K2PdCl6) in a concentration equal to from 0.03 to 0.15% by moles of the silver halide in the emulsion.
  • KzPdCh potassium chloropalladite
  • KzPdBrs potassium bromopalladate
  • a process for preparing a high speed photographic silver halide emulsion comprising sensitizing the emulsion with at least one gold compound in a concentration equal to from 0.0003 to 0.015% by moles of the silver halide in the emulsion and adding to the sensitized emulsion at least one palladium salt selected from the group consisting of palladium salts represented by the following general formula:
  • IMzPdXs and M2PdX4 wherein M represents a member selected from the group consisting of an alkali metal atom and an ammonium radical, and X represents a halogen atom selected from the group consisting of chlorine, bromine and iodine atoms, the con centration of said palladium salt in the emulsion being equal to from 0.015 to 0.2% by moles of the silver halide in the emulsion.
  • a process for preparing a high speed photographic silver halide emulsion comprising sensitizing the emulsion with at least one gold compound in a concentration equal to from 0.001 to 0.01% by moles of the silver halide in the emulsion and at least one sulfur sensitizer. and adding to the sensitized emulsion at least one palladium salt selected from the group consisting of palladium salts represented by the following general formulas:
  • M represents a member selected from the group consisting of an alkali metal atom and an ammonium radical
  • X represents a halogen atom selected from the group consisting of chlorine, bromine and iodine atoms, the concentration of said palladium salt in the emulsion being equal to from 0.015 to 0.2% by moles of the silver halide in the emulsion.
  • a process for preparing a high speed photographic silver halide emulsion comprising sensitizing the emulsion by digesting it on the acid side of neutrality in the presence of at least one gold compound in a concentration equal to from 0.001 to 0.01% by moles of the silver halide in the emulsion and at least one sulfur sensitizer, and adding to the sensitized emulsion at least one palladium salt selected from the group consisting of palladium salts represented by the following general formulas:
  • M represents a member selected from the group consisting of an alkali metal atom and an ammonium radical
  • X represents a halogen atom selected from the group consisting of chlorine, bromine and iodine atoms

Landscapes

  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • General Physics & Mathematics (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
US47108A 1948-08-31 1948-08-31 High-speed photographic silver halide emulsions supersensitized with palladium salts Expired - Lifetime US2598079A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
BE490866D BE490866A (en)) 1948-08-31
US47108A US2598079A (en) 1948-08-31 1948-08-31 High-speed photographic silver halide emulsions supersensitized with palladium salts
GB22520/49A GB659033A (en) 1948-08-31 1949-08-30 Improvements in sensitive photographic emulsions
FR1007305D FR1007305A (fr) 1948-08-31 1949-08-31 Nouvelles émulsions photographiques très rapides et leur procédé de préparation
DEE2142A DE964561C (de) 1948-08-31 1950-09-17 Supersensibilisierte photographische Halogensilberemulsion und Verfahren zur Herstellung derselben

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US47108A US2598079A (en) 1948-08-31 1948-08-31 High-speed photographic silver halide emulsions supersensitized with palladium salts

Publications (1)

Publication Number Publication Date
US2598079A true US2598079A (en) 1952-05-27

Family

ID=21947103

Family Applications (1)

Application Number Title Priority Date Filing Date
US47108A Expired - Lifetime US2598079A (en) 1948-08-31 1948-08-31 High-speed photographic silver halide emulsions supersensitized with palladium salts

Country Status (5)

Country Link
US (1) US2598079A (en))
BE (1) BE490866A (en))
DE (1) DE964561C (en))
FR (1) FR1007305A (en))
GB (1) GB659033A (en))

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2816029A (en) * 1955-03-08 1957-12-10 Eastman Kodak Co Supersensitizing combinations comprising simple cyanine dyes and metal salts
US2819964A (en) * 1955-03-08 1958-01-14 Eastman Kodak Co Supersensitizing combinations comprising meso-substituted carbocyanine dyes and metal salts
US2839405A (en) * 1955-03-08 1958-06-17 Eastman Kodak Co Inorganic salt antifoggants for photographic emulsions
US2843490A (en) * 1955-03-08 1958-07-15 Eastman Kodak Co Supersensitizing combinations comprising meso-substituted carbocyanine dyes and polyvalent metal salts
US2950972A (en) * 1954-11-24 1960-08-30 Gen Aniline & Film Corp Photographic emulsions having increased sensitivity to x-ray and gamma ray radiation
DE2252585A1 (de) * 1971-10-28 1973-05-03 Fuji Photo Film Co Ltd Photographische silberbromjodidemulsionen mit verbesserter gruen-empfindlichkeit
EP0124795A2 (en) 1983-04-11 1984-11-14 Fuji Photo Film Co., Ltd. Silver halide photographic emulsion
EP0368304A1 (en) * 1988-11-11 1990-05-16 Fuji Photo Film Co., Ltd. Method of manufacturing silver halide photographic emulsion
WO1993002390A1 (en) * 1991-07-22 1993-02-04 Eastman Kodak Company Gold compounds as antifoggants in high silver chloride emulsions
EP0693707A1 (en) * 1994-07-21 1996-01-24 Minnesota Mining And Manufacturing Company Light-sensitive silver halide photographic element
EP0722115A1 (en) * 1994-12-16 1996-07-17 Eastman Kodak Company Photographic element and coating composition
US5582957A (en) * 1995-03-28 1996-12-10 Eastman Kodak Company Resuspension optimization for photographic nanosuspensions
US5650265A (en) * 1995-12-22 1997-07-22 Eastman Kodak Company Silver halide light-sensitive element
US5759760A (en) * 1997-06-04 1998-06-02 Eastman Kodak Company Aqueous solid particle dispersions in chemical sensitization
US5763154A (en) * 1996-08-07 1998-06-09 Eastman Kodak Company Palladium chemical sensitizers for silver halides
WO2012035314A1 (en) 2010-09-17 2012-03-22 Fujifilm Manufacturing Europe Bv Photographic paper
WO2021213762A1 (en) 2020-04-24 2021-10-28 Fujifilm Manufacturing Europe Bv Photographic paper

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1570581A (en) * 1978-05-25 1980-07-02 Ciba Geigy Ag Preparation of silver halide emulsions

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2059642A (en) * 1934-03-10 1936-11-03 Kankelwitz Bruno Process for manufacturing photographic silver halide developing emulsions durably free from grey and yellow fogging and of durable quality
US2399083A (en) * 1942-02-13 1946-04-23 Ilford Ltd Photographic materials
US2448060A (en) * 1945-08-30 1948-08-31 Eastman Kodak Co Photographic emulsions sensitized with salts of metals of group viii of the periodicarrangement of the elements
US2540086A (en) * 1948-06-17 1951-02-06 Silver halibe emulsions

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2059642A (en) * 1934-03-10 1936-11-03 Kankelwitz Bruno Process for manufacturing photographic silver halide developing emulsions durably free from grey and yellow fogging and of durable quality
US2399083A (en) * 1942-02-13 1946-04-23 Ilford Ltd Photographic materials
US2448060A (en) * 1945-08-30 1948-08-31 Eastman Kodak Co Photographic emulsions sensitized with salts of metals of group viii of the periodicarrangement of the elements
US2540086A (en) * 1948-06-17 1951-02-06 Silver halibe emulsions

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2950972A (en) * 1954-11-24 1960-08-30 Gen Aniline & Film Corp Photographic emulsions having increased sensitivity to x-ray and gamma ray radiation
US2816029A (en) * 1955-03-08 1957-12-10 Eastman Kodak Co Supersensitizing combinations comprising simple cyanine dyes and metal salts
US2819964A (en) * 1955-03-08 1958-01-14 Eastman Kodak Co Supersensitizing combinations comprising meso-substituted carbocyanine dyes and metal salts
US2839405A (en) * 1955-03-08 1958-06-17 Eastman Kodak Co Inorganic salt antifoggants for photographic emulsions
US2843490A (en) * 1955-03-08 1958-07-15 Eastman Kodak Co Supersensitizing combinations comprising meso-substituted carbocyanine dyes and polyvalent metal salts
DE2252585A1 (de) * 1971-10-28 1973-05-03 Fuji Photo Film Co Ltd Photographische silberbromjodidemulsionen mit verbesserter gruen-empfindlichkeit
EP0124795A2 (en) 1983-04-11 1984-11-14 Fuji Photo Film Co., Ltd. Silver halide photographic emulsion
EP0368304A1 (en) * 1988-11-11 1990-05-16 Fuji Photo Film Co., Ltd. Method of manufacturing silver halide photographic emulsion
WO1993002390A1 (en) * 1991-07-22 1993-02-04 Eastman Kodak Company Gold compounds as antifoggants in high silver chloride emulsions
EP0693707A1 (en) * 1994-07-21 1996-01-24 Minnesota Mining And Manufacturing Company Light-sensitive silver halide photographic element
US6534255B1 (en) 1994-07-21 2003-03-18 Eastman Kodak Company Light-sensitive silver halide photographic element
EP0722115A1 (en) * 1994-12-16 1996-07-17 Eastman Kodak Company Photographic element and coating composition
US5614360A (en) * 1994-12-16 1997-03-25 Eastman Kodak Company Photographic element and coating composition
US5582957A (en) * 1995-03-28 1996-12-10 Eastman Kodak Company Resuspension optimization for photographic nanosuspensions
US5650265A (en) * 1995-12-22 1997-07-22 Eastman Kodak Company Silver halide light-sensitive element
US5763154A (en) * 1996-08-07 1998-06-09 Eastman Kodak Company Palladium chemical sensitizers for silver halides
US5759760A (en) * 1997-06-04 1998-06-02 Eastman Kodak Company Aqueous solid particle dispersions in chemical sensitization
WO2012035314A1 (en) 2010-09-17 2012-03-22 Fujifilm Manufacturing Europe Bv Photographic paper
WO2021213762A1 (en) 2020-04-24 2021-10-28 Fujifilm Manufacturing Europe Bv Photographic paper

Also Published As

Publication number Publication date
FR1007305A (fr) 1952-05-05
GB659033A (en) 1951-10-17
BE490866A (en))
DE964561C (de) 1957-05-23

Similar Documents

Publication Publication Date Title
US2598079A (en) High-speed photographic silver halide emulsions supersensitized with palladium salts
US2448060A (en) Photographic emulsions sensitized with salts of metals of group viii of the periodicarrangement of the elements
US3656955A (en) Silver halide emulsion sensitized with pentathiepane
GB618061A (en) Improvements in sensitive photographic materials
US3033682A (en) Radiation-sensitive emulsions, elements, and processes for making same
US2983609A (en) Chemical sensitization of photographic emulsions
US2983610A (en) Sensitization of photographic emulsions
US3144336A (en) Synergistic sensitization of photographic silver halide emulsions
US4067740A (en) Trithiocarbonates as sensitizers for silver halide emulsions
US2728664A (en) Photographic emulsions containing mercury salts
US3779764A (en) Silver halide emulsions for the production of reversal colorphotographic images
US3573920A (en) Fine grain silver halide emulsions containing novel dye combinations
US3857711A (en) Silver halide photographic emulsion sensitized with a heterocyclic compound containing 4-sulfur atoms
US2728667A (en) Molecular compounds of mercury salts with benzothiazoles as fog inhibitors in a silver halide emulsion
US2743183A (en) Chemical sensitization of photographic emulsions
US3006762A (en) Sensitizers for photographic emulsions
US3396022A (en) Quinone stabilizers and antifoggants for silver halide emulsions
US3458316A (en) Light sensitive silver halide emulsions
US3622329A (en) Photographic silver halide emulsions with increased sensitivity
US3062645A (en) Sensitization of photographic emulsions to be developed with p-phenylenediamine developing agents
US3573915A (en) Photographic silver halide emulsions containing nitrosubstituted or unisubstituted cinnamic acid or cinnamaldehyde
US3779777A (en) Silver halide emulsion sensitized with a polyhedral haloborane
US3761275A (en) Boron hydrides as reduction sensitizers in developing out silver halide emulsions
US2728665A (en) Photographic emulsions containing mercuric compounds having carbon-mercury bond
US3137577A (en) Process for increasing the sensitivity of photographic silver halide emulsion