EP0407576A1 - Materiau photographique a base d'halogenure d'argent et procede de preparation - Google Patents

Materiau photographique a base d'halogenure d'argent et procede de preparation Download PDF

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Publication number
EP0407576A1
EP0407576A1 EP89901593A EP89901593A EP0407576A1 EP 0407576 A1 EP0407576 A1 EP 0407576A1 EP 89901593 A EP89901593 A EP 89901593A EP 89901593 A EP89901593 A EP 89901593A EP 0407576 A1 EP0407576 A1 EP 0407576A1
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EP
European Patent Office
Prior art keywords
silver halide
silver
grains
reaction vessel
halide grains
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.)
Withdrawn
Application number
EP89901593A
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German (de)
English (en)
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EP0407576A4 (fr
Inventor
Shigeharu Urabe
Shun-Ichi Aida
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Fujifilm Holdings Corp
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Fuji Photo Film Co Ltd
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Filing date
Publication date
Priority claimed from JP785288A external-priority patent/JPH01183644A/ja
Priority claimed from JP63007851A external-priority patent/JPH0723218B2/ja
Priority claimed from JP63007853A external-priority patent/JPH07104569B2/ja
Priority claimed from JP63194861A external-priority patent/JPH0769580B2/ja
Priority claimed from JP63194862A external-priority patent/JPH0778600B2/ja
Priority claimed from JP63195778A external-priority patent/JPH0782208B2/ja
Application filed by Fuji Photo Film Co Ltd filed Critical Fuji Photo Film Co Ltd
Publication of EP0407576A4 publication Critical patent/EP0407576A4/fr
Publication of EP0407576A1 publication Critical patent/EP0407576A1/fr
Withdrawn legal-status Critical Current

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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
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/0051—Tabular grain emulsions
    • 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
    • G03C1/10—Organic substances
    • G03C1/12—Methine and polymethine dyes
    • G03C1/14—Methine and polymethine dyes with an odd number of CH groups
    • G03C1/18—Methine and polymethine dyes with an odd number of CH groups with three CH groups
    • 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
    • G03C1/04—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with macromolecular additives; with layer-forming substances
    • G03C1/047—Proteins, e.g. gelatine derivatives; Hydrolysis or extraction products of proteins
    • G03C2001/0473—Low molecular weight gelatine

Definitions

  • This invention relates to a silver halide photographic material useful in the field of photography and a process of producing it. More particularly, the invention relates to a silver halide photographic material having high sensitivity and a fine graininess.
  • the fundamental performance required for a photographic silver halide emulsion is a high sensitivity, low fog, and a fine graininess.
  • the sensitivity of an emulsion it is required (1) to increase the number of photons being absorbed by one grain, (2) to increase the efficiency of conversing the photoelectrons generated by light absorption into silver clusters (latent images), and (3) to increase the development activity for effectively utilizing the latent images formed.
  • the increase of the grain size increases the number of photons being absorbed by one grain but reduces the image quality.
  • the increase of the development activity is an effective means for increasing the sensitivity but is generally accompanied by the reduction of graininess in the case of a parallel type development such as color development.
  • it is most preferred to increase the efficiency of converting photoelectrons into latent images that is, to increase the quantum sensitivity.
  • Patents 2,518,698, 3,201,254, 3,411,917, 3,779,777 and 3,930,867 are disclosed in JP-B-57-33572 and JP-B-58-1410 and JP-A-57-179835.
  • JP-B and JP-A as used herein mean an "examined Japanese patent publication", and an "unexamined published Japanese patent application”, respectively.
  • techniques for improving the storage stability of emulsions reduction sensitized are disclosed in JP-A-57-82831 and JP-A-60-178445.
  • Light-sensitive silver halide grains for high-speed silver halide photographic materials are generally gold-sulfur sensitized at the surfaces of the grains and also since a reduction sensitization and a gold sensitization are used together, it causes severe formation of fog, various investigations on the reduction sensitization for the insides of grains have been carried out.
  • the grains are generally produced by reacting an aqueous silver salt solution and an aqueous halide solution in an aqueous colloid solution in a reaction vessel.
  • a single jet method of placing an aqueous solution of protective colloid such as gelatin and an aqueous halide solution in a reaction vessel and adding thereto an aqueous silver salt solution with stirring over a period of a certain time and a double jet method of placing an aqueous gelatin solution in a reaction vessel and adding thereto an aqueous silver salt solution and an aqueous halide solution over a period of certain time are known.
  • the double jet method provides silver halide grains having a narrower grain size distribution and in the method, the halide composition can be freely changed with the growth of the grains.
  • the growing rate of silver halide grains is greatly influenced by the concentration of silver ions (halogen ions) in a reaction solution, the concentration of a silver halide solvent, the distance between grains, grain sizes, etc.
  • the heterogeneity of the concentration of silver ions or halogen ions formed from an aqueous silver salt solution and an aqueous halide solution added to a reaction vessel makes differ the growing rate by each concentration, which results in forming a silver halide emulsion having heterogeneity.
  • a hollow rotary mixer (the inside thereof is filled with an aqueous colloid solution, and more preferably, the mixer is partitioned into .an upper room and a lower room by a disk) of an intermediate size having slits at the cylindrical wall is disposed in an reaction vessel filled with an aqueous colloid solution so that the rotary axis thereof is perpendicular, an aqueous halide solution and an aqueous silver salt solution are supplied from the upper and lower openings thereof into the mixer rotating at a high speed through feed pipes to quickly mixing them and to cause reaction (when the mixer is separated into the upper room and the lower room by a separation disk, the aqueous halide solution and the aqueous silver salt solution supplied into the upper and lower rooms are diluted with an aqueous colloid solution filled in each room and are quickly mixed with each other at the vicinity of the outlet slits of the mixer to cause the reaction), and silver halide grains formed by the centrifugal force caused by the rotation of the mixer are
  • JP-B-55-10545 a technique of preventing the heterogeneous growth of silver halide grains by improving the localization of the concentrations.
  • This method is a technique in which an aqueous halide solution and an aqueous silver salt solution are separately supplied into a mixer filled with an aqueous colloid solution through feed pipes from the lower open portions, said mixer being placed in a reaction vessel filled with an aqueous colloid solution, the reaction solutions are abruptly stirred and mixed by means of lower stirring blades (turbine blades) equipped to the mixer to grow silver halide grains, and the silver halide grains thus grown are immediately discharged into the aqueous colloid solution in the reaction vessel from the upper open portion of the mixer by upper stirring blades disposed at the upper portion of the aforesaid lower stirring blades.
  • JP-A-57-92523 also discloses a production method of silver halide grains for improving the heterogeneity of the concentrations.
  • This method is a production method of silver halide grains by separately supplying an aqueous halide solution and an aqueous silver salt solution into a mixer filled with an aqueous colloid solution from the open lower portion thereof, said mixer being placed in a reaction vessel filled with an aqueous colloid solution, to dilute both the reaction solutions with the aforesaid aqueous colloid solution, abruptly stirring and mixing both the reaction solutions by means of lower stirring blades equipped to the mixer, and immediately discharging the silver halide grains thus grown into the aqueous colloid solution in the reaction vessel from the upper open portion of the mixer, wherein both the reaction solutions diluted with the aqueous colloid solution are passed through the gap formed between the inside wall of the mixer and the tops of the stirring blades without passing through each gap between the stirring blades, whereby both the reaction solutions are abruptly sheared and
  • the local heterogeneity of the concentrations of silver ions and halogen ions in a reaction vessel can be surely overcome, in these methods, the heterogeneity of the concentrations yet exists in the mixer and, in particular, there is a considerably large concentration distribution at the vicinities of the nozzles for supplying the aqueous silver salt solution and the aqueous halide solution, at the lower portions of the stirring blades, and the stirring portion. Furthermore, the silver halide grains supplied to the mixer together with the protective colloid pass through such portions having the heterogeneous concentration distribution and more seriously, the silver halide grains abruptly grow in these portions.
  • JP-A-53-37414 and JP-B-48-21045 disclose a method and apparatus of producing silver halide grains by circulating an aqueous protective colloid solution (containing silver halide grains) in a reaction vessel from the bottom of the reaction vessel by means of a pump, equipping a mixer to the circulation system, supplying an aqueous silver salt solution and an aqueous halide solution into the mixer, and abruptly mixing both the aqueous solutions in the mixer to grow silver halide grains.
  • U.S. Patent 3,897,935 discloses a method of circulating an aqueous protective colloid soluti.. (containing silver halide grains) in a reaction vessel from the bottom nf the reaction vessel and pouring an aqueous halide solution and an aqueous silver salt solution into the circulation system by means of a pump.
  • JP-A-53-47397 discloses a method and apparatus of producing silver halide grains by circulating an aqueous protective colloid solution (containing silver halide grains) in a reaction vessel from the reaction vessel by means of a pump, pouring first an aqueous alkali metal halide solution into the circulation system to disperse until the mixture becomes uniform, and then pouring an aqueous silver salt solution into the system followed by mixing to form silver halide grains.
  • the heterogeneity of silver ion concentration in the range of causing the grain growth is unavoidable.
  • Such a heterogeneity of silver ion concentration not only becomes a heterogeneity of the reductive atmosphere in the reaction vessel by itself but also causes the heterogeneity of the silver nucleus forming reaction by the heterogeneity in the case of using a reducing agent together.
  • the silver nucleus forming reaction can be generally shown by nAg + + ne- - Agn but the existence of the heterogeneity of silver ion concentration in the domain of causing the grain growth namely means that the left side of the aforesaid formula showing the silver nucleus forming reaction differs in each spot in the domain of causing the grain growth.
  • the object of this invention is to provide a silver halide emulsion having high sensitivity and good graininess and a process of producing a silver halide emulsion having high sensitivity and giving less fog. Also, the 2nd object of this invention is to provide a photographic light-sensitive material having high sensitivity and good graininess and also to provide a photographic light-sensitive material having high sensitivity and giving less fog.
  • the production process of a silver halide emulsion is generally composed of the steps of grain formation, desalting, chemical sensitization, coating, etc.
  • the grain formation is composed of a nucleus formation, ripening, growing, etc. These steps are not carried out in a definite order but as the case may be, the order of the steps is reversed or the steps are repeatedly carried out.
  • a part or the whole of the grain formation in the aforesaid steps is carried out "under the condition capable of reduction sensitizing” or “under the condition capable of reduction sensitizing and further under the condition of existing an oxidizing agent and/or an inhibitor” (hereinafter, is referred to as “reduction sensitizing”).
  • the silver halide grain formation is roughly divided into “nucleus formation” and “growth” and the “growth” is further divided into a narrow sense “growth” which is proceeded by supplying silver halide grains being supplied for the crystal grow from outside a reaction vessel for causing the crystal growth and "ripening" which is proceeded without supply of silver halide grains from outside.
  • the reduction sensitization of this invention may be applied at any step of the aforesaid grain formation or after the grain formation. It is preferred that the grain growth is performed .by adding silver halide grains having fine grain sizes under the condition capable of reduction sensitizing. In the case of performing a chemical sensitization using a gold sensitization together, it is preferred to perform the reduction sensitization prior to the chemical sensitization such that undesirable fog is not formed and it is more preferred that the reduction sensitization is applied to the inside of the silver halide grains and the content of reduced silver nuclei causing fog with the gold sensitization is reduced in the surface of the grains to which the gold sensitization is applied.
  • the reduction sensitization of this invention can be carried out by a method of adding a known reducing agent to a silver halide emulsion, a method of growing or ripening silver halide grains in an atmosphere of low pAg of from pAg of 1 to 7, called as silver ripening, or a method of growing or ripening silver halide grains in an atmosphere of high pH of from 8 to 11, called as high pH ripening. Also, two or more of the methods can be used together.
  • the method of adding a reduction sensitizer is preferred in the point capable of finely controlling the level of the reduction sensitization.
  • the reduction sensitizers there are known stannous salts, amines, polyamines, hydrazine derivatives, formamizinesulfinic acid, ascorbic acid derivatives, hydroquinone derivatives, silane compounds, borane compounds, etc.
  • the aforesaid compounds can be used and two or more compounds can be used together.
  • stannous chloride, thiourea dioxide, and dimethylamineborane are preferred.
  • the addition amount of the reduction sensitizer depends upon the production condition of the silver halide emulsion but is properly in the range of from 10-7 to 10-3 mol per mol of silver halide.
  • an ascorbic acid derivative is also a preferred compound as the reduction sensitizer and in this case, the addition amount is properly in the range of from 5 x 10-5 to 1 x 10-1 mol per mol of silver halide.
  • the reduction sensitizer is added to the system of forming silver halide grains as a solution thereof in water, an alcohol, a glycol, a ketone, an ester, an amide, etc.
  • the solution may be previously placed in a reaction vessel for causing the grain formation or may be added at a proper time of the grain formation.
  • the solution of the reduction sensitizers may be added in several times with the formation of grains or may be continuously added for a long period of time.
  • an oxidizing agent and/or an inhibitor can exist with a reducing agent for controlling the level of the reduction sensitization.
  • the coexistence of an oxidizing agent and/or an inhibitor in the reduction sensitization of this invention is mainly for two purposes.
  • the first purpose is that the reducing agent added for practicing the reduction sensitization at a necessary time in the step of forming grains is inactivated by the addition of an oxidizing agent and/or an inhibitor when the reduction sensitization becomes unnecessary to stop the occurrence of unnecessary reduction sensitized nuclei.
  • the use of the oxidizing agent and/or the -nhibitor by the first purpose makes it possible to control the distrik tion of the reduction sensitized nuclei in the light-sensitive silver halide grains.
  • the second purpose of using the oxidizing agent and/or the inhibitor is in that at performing the reduction sensitization by a reductive atmosphere of low pAg or high pH, or by a reducing agent, the extent of the reduction sensitization (the extent is considered to be influenced by the sizes or the number of reduced silver nuclei) is controlled to realize the optimum performance.
  • the oxidizing agent which is used for the aforesaid purposes may be an inorganic compound or an organic compound. Suitable examples are iodide, hexacyano iron(III) salts, bromosuccinimide, quinone derivatives, periodates, persulfates, pentacyanonitrosyl iron acid salts, N(m-nitrobenzyl)quinolinium chloride, etc. Also, the compounds of following general formulae [I] to [III] are preferred as the oxidizing agents in this invention.
  • the inhibitor which is used for the aforesaid purposes may be an inorganic compound or an organic compound.
  • the inhibitor which is used for the aforesaid purposes may be an inorganic compound or an organic compound.
  • soluble halides for controlling pAg and acids and alkalis as well as organic compounds capable of adsorbing on the surface of silver halide grain, which are used as so-called stabilizers, (e.g., mercapto compounds and heterocyclic compounds) for controlling pH.
  • the compound capable of adsorbing on the surface of silver halide grains the compound having a low inhibiting power for the growth of the silver halide grains by the compound is preferred.
  • the methods of using the oxidizing agents and/or the inhibitors described above may be preferably used as a combination thereof.
  • the amount of the oxidizing agent or the inhibitor and the selection of pAg or pH depend upon the kind and the amount of the reducing agent.
  • the amount of the oxidizing agent is selected according to the oxidation- reduction potential of the reducing agent and the oxidizing agent and also for the purpose of using the oxidizing agent and, for example, in the case of controlling the extent of the reduction sensitization, the amount of the compound shown by general formula [I], [II], or [III] is preferably from 10- 7 to 10-1 mol, more preferably from 10-6 to 10- 2 mol, and particularly preferably from 10-5 to 10-3 mol per mol of silver halide.
  • a method which is usually used in the case of adding additives to a photographic emulsion can be used.
  • a water-soluble compound can be added as an aqueous solution thereof of a proper concentration and a compound insoluble in water or sparingly soluble in water can be added as a solution thereof in an organic solvent miscible with water, such as alcoholos, glycols, ketones, esters, amides, etc., which does not give bad influences on the photographic characteristics.
  • the time for adding the additives may be at any step during the grain formation of the silver halide emulsion.
  • the additive may be added at the time when the reduction sensitization during the grain formation becomes unnecessary.
  • the oxidizing agent and/or the inhibitor it is preferred to add the oxidizing agent and/or the inhibitor before the addition of the reducing agent or setting the reducing atmosphere (pAg, pH) but the addition may be at the same . time or the order may be reversed.
  • the additive may be previously added to the reaction vessel or may be added at a proper time of the grain formation.
  • the oxidizing agent and/or the inhibitor may be added as a solution thereof in several times with the growth of the grains or may be continuously added for a long period of time.
  • the compounds of aforesaid general formulae [I] to [III] are preferred and the compound of general formula [I] is more preferred.
  • the control of pAg by the addition of a soluble halide and the control of pH by the addition of acid are also preferably used for the second purpose. Also, if bad influences are not given to the growth of the grains, a means of reducing the temperature of the reaction vessel for causing the grain growth, etc., may be used.
  • the nucleus formation and/or the crystal growth of silver halide grains are performed in the reaction vessel.
  • the aqueous silver salt solution and the aqueous halide solution are not added to the reaction vessel for the nucleus formation and/or the crystal growth except for adjusting pAg of the emulsion in the reaction vessel, and further the aqueous protective colloid solution (containing silver halide grains) in the reaction vessel is not circulated into the mixer.
  • the nuclei of the grains can be formed and further the growth of the crystals can be carried out in the reaction vessel.
  • the growth of the crystals can also be carried out.
  • Method A By immediately supplying the fine grains formed by mixing an aqueous solution of a water-soluble silver salt and an aqueous solution of water-soluble halides in a mixer disposed outside the reaction vessel for causing the nucleus formation and/or the crystal growth to the reaction vessel, the nucleus formation and/or the crystal growth of the silver halide core grains is carried out (hereinafter, is referred to as Method A).
  • a reaction vessel 1 contains an aqueous solution 2 of a protective colloid.
  • the aqueous solution of the protective colloid is stirred by a propeller 3 attached to a rotary shaft.
  • An aqueous solution of silver salt, an aqueous solution of halides, and an aqueous solution of a protective colloid are introduced into a mixer 7 outside the reaction vessel through feed systems 4, 5, and 6, respectively.
  • the aqueous protective colloid solution may be added as a mixture with the aqueous halide solution and/or the aqueous silver salt solution).
  • a reaction chamber 10 is formed in the mixer 7 and a stirring blade 9 fixed to a rotary shaft 11 is equipped in the reaction chamber 10.
  • An aqueous silver salt solution, an aqueous halide solution, and an aqueous protective colloid solution are added to the reaction chamber 10 from three inlets (4, 5, and one inlet is omitted from the figure).
  • a high speed at least 1000 r.p.m., preferably at least 2000 r.p.m., and more preferably at least 3000 r.p.m.
  • the mixture is quickly and strongly mixed and a solution containing very fine grains thus formed is immediately discharged from an outlet 8.
  • the very fine grains formed in the mixer are then introduced into the reaction vessel, easily dissolved due to the fineness of the grain size to form silver ions and halogen ions again, and cause the formation of homogeneous growth of grains.
  • the halide composition of the very fine grains is selected such that it is same as the halide composition of silver halide grains being formed.
  • the very fine grains introduced into the reaction vessel are dispersed in the reaction vessel by stirring in the reaction vessel to release halogen ions and silver ions of the halide composition being formed from each fine grain.
  • the grains formed in the mixer is very fine, the number of the grains is very large, and since the silver ions and halogen ions (in the case of the growth of mixed crystals, the desired halogen ion composition is formed) are released from a very large number of grains and they are released over the whole protective colloid in the reaction vessel, the completely homogeneous nuclei formation and/or the growth of completely homogeneous grains can be caused. It is important that silver ions and halogen ions are never added to the reaction vessel as aqueous solution thereof except for pAg control and the protective colloid solution in the reaction vessel is not circulated in the mixer. The method can give an astonishing effect in the homogeneous growth of silver halide grains different from conventional methods.
  • the fine grains formed in the mixer have a very high solubility since the grain size thereof is very fine, dissolved when added to the reaction vessel to form silver ions and halogen ions again, and nuclei are formed or they are deposited on the grains already existing in the reaction vessel to cause the grain growth.
  • the fine silver halide grains have a high solubility, the fine grains cause so-called Ostwald ripening in the mixer before being added to the reaction vessel to increase the grain sizes. If the size of fine grains is increased, the solubility thereof is lowered with the increase of the size, the dissolution thereof in the reaction vessel is delayed, the grain growing rate is greatly reduced, and in some case, the fine grains cause the grain growth as the nuclei thereof without being dissolved.
  • the residence time (t) of the solutions added to the mixer is shown as follows.
  • t is not longer than 10 minutes, preferably not longer than 5 minutes, more preferably not longer than 1 minute, and far more preferably not longer than 20 seconds.
  • the stirring blade of the reaction chamber can be rotated at a high rotation number since a closed type mixer shown in Fig. 2 is used but it is impossible in a conventional open type reaction vessel (i.e., in an open type reaction vessel, when a stirring blade is rotated at a high speed, the liquid is scattered by the centrifugal force and hence such as operation is unapplicable practically with an additional problem of foaming). That is, in this invention, it is possible to employ mixing by strong and efficient stirring for preventing the occurrence of the aforesaid coalescence ripening, which results in the formation of very fine grains having very fine grain sizes.
  • the rotation number of the stirring blade is at least 1000 r.p.m., preferably at: least 2000 r.p.m., and more preferably at least 3000 r.p.m..
  • a protective colloid for silver halide grains The occurrence of aforesaid coelescence ripening can be markedly prevented by a protective colloid for silver halide grains.
  • an aqueous protective colloid solution is added to the mixer as follows:
  • the concentration of the protective colloid is at least 0.2% by weight, and preferably at least 0.5% by weight and the flow rate thereof is at least 20%, preferably at least 50%, and more preferably at least 100 % of the sum of the flow rate of an aqueous silver nitrate solution and the flow rate of an aqueous halide solution.
  • the concentration of the protective colloid is at least 0.2% by weight, and preferably at least 0.5% by weight.
  • the concentration of the protective colloid is at least 0.2% by weight, and preferably at least 0.5%, by weight.
  • gelatin since gelatin silver is formed by silver ions and gelatin and gelatin silver forms silver colloid by causing photodecomposition and thermal decomposition, it is better to mix an aqueous silver nitrate solution and an aqueous protective colloid solution directly before use.
  • aforesaid methods (a) to (c) may be used solely or as a combination thereof. Furthermore, the three methods may be simultaneously used.
  • Method B a method of adding a fine grain silver halide emulsion containing silver halide grains of fine grain size previously prepared to a reaction vessel to perform the formation of nuclei and/or the growth of the grains (hereinafter, is referred to as "Method B”) can be used.
  • the grain size of the previously prepared emulsion is fine.
  • an aqueous silver salt solution and an aqueous halide solution are not added to the reaction vessel for causing the nucleus formation and/or the crystal growth except for pAg control of the emulsion in the reaction vessel as in the aforesaid method.
  • the previously prepared emulsion may be previously washed with water and/or gelled before adding to the reaction vessel.
  • gelatin is preferably used as the protective colloid.
  • low molecular weight gelatin is used in this invention.
  • the average molecular weight of gelatin is preferably not more than 30,000 and more preferably not more than 10,000.
  • the formation of fine grain silver halide grains can be performed at a lower temperature than the case of using ordinary gelatin and silver halide having finer grain sizes can be provided.
  • the concentration of the protective colloid being added to the mixer in Method A is at least 0.2% by weight, preferably at least 1 % by weight, and more preferably at least 2% by weight.
  • the concentration thereof is at least 0.2% by weight, preferably at least 1% by weight, and more preferably at least 2 % by weight.
  • the concentration of the protective colloid in the reaction vessel at the preparation 3 f the fine grain emulsion is at least 0.2%.by weight, preferably at least 1% by weight, and more preferably at least 2% by weight.
  • the temperature of the mixer is not higher than 40°C, and preferably not higher than 35°C and the temperature of the reaction vessel is not lower than 50°C, and preferably not lower than 60°C, and more preferably not lower than 70°C.
  • the grain forming temperature for the fine grain emulsion being previously prepared is not higher than 40°C, and preferably not higher than 35°C and the temperature of the reaction vessel to which the fine grain emulsion is added is not lower higher than 50°C, preferably not lower than 60°C, and more preferably not lower than 70°C.
  • the grain size of the silver halide grains having fine grain sizes for use in this invention can be confirmed by a transmission type electron microscope on a mesh and the magnification thereof is preferably from 20,000 to 40,000.
  • the grain size of the fine silver halide grains for use in this invention is not larger than 0.2 ⁇ m, preferably not larger than 0.1 ⁇ m, and more preferably not larger than 0.05 ⁇ m.
  • Method A can provide fine grains having finer grain sizes than Method B by employing the means of (1) fine silver halide grains are immediately added to the reaction vessel after the formation thereof, (2) strong stirring is applied, (3) an aqueous solution of protective colloid is poured into the mixer, etc.
  • silver halide solvent there are water-soluble bromides, water-soluble chlorides, thiocyanates, ammonia, thioethers, thioureas, etc.
  • thiocyanates U.S. Patents 2,222,264, 2,448,534, and 3,320,069
  • ammonia thioether compounds
  • thioether compounds U.S. Patents 3,271,157, 3,574,628, 3,704,130, 4,297,439, and 4,276,347
  • thione compounds e.g., JP-A-53-144319, JP-A-53-82408, and JP-A-55-77737
  • amine compounds e.g., JP-A-54-100717
  • thiourea derivatives e.g., JP-A-55-2983
  • imidazoles e.g., JP-A-54-100717
  • substituted mercaptotetrazoles e.g., JP-A-57-202531
  • the halide composition of the emulsion obtained by the present invention may be silver iodobromide, silver chlorobromide, silver chloroiodobromide, or silver chloroiodide and according to this invention, silver halide mixed crystal grains having a homogeneous microscopic distribution of halide, that is, "complete homogeneity" are obtained.
  • the "completely homogeneous silver iodide distribution" in this invention completely differs from a conventional silver iodide distribution and a more microscopic distribution.
  • Analytical Electron Microscopy has been well used. For example, in M.A. King, M.H. Lorretto, T.J. Maternaghan, and F.J.
  • the size of the probe for electron ray irradiation used in the investigations is 50 ⁇ but actually, the electron beam is broarded by the elastic scattering of electron and the diameter of the spot of the electron irradiated onto the surface of the sample becomes about 300 ⁇ . Accordingly, a finer silver iodide distribution than the diameter can not be measured by the method. In JP-A-58-113927, a silver iodide distribution was measured by the same manner but the size of the spot of the electron been used was 0.2 ⁇ m.
  • the microscopic silver iodide distribution can be observed by a direct method of using a transmission type electron microscope at a low temperature described, for example, in J.H. Hamilton, Photographic Science and Engineering, Vol. 11, page 57, (1967) and Takekimi Shinozawa, Journal of the Society of Photographic Science and Technology of Japan, Vol. 35, No. 4, page 213, (1972).
  • silver halide grains taken out under safe light such that the emulsion grains are not printed out are placed on a mesh for electron microscopic observation and the observation of the sample is carried out in the state of being cooled by liquid nitrogen or liquid helium for preventing the occurrence of damages (print out, etc.) of the sample by electron beams.
  • the photographing magnification can be properly changed according to the size of the grains but is from 20,000 to 40,000 magnifications.
  • the tabular grains shown in the figure are grains composed of tabular silver bromide grain as the core and silver iodobromide containing 10 mol% of silver iodide as the shell formed at the outside of the core and the structure can be clearly confirmed by the transmission type electron microphotograph.
  • the core portion is silver bromide and is, as a matter of course, homogeneous, homogeneous flat images only are obtained but, on the other hand, a very fine annular ring-like striped pattern is clearly confirmed in the silver iodobromide phase.
  • the striped pattern has a very fine interval as the order of 100 A or less, which shows a very microscopic heterogeneity.
  • the very fine striped pattern shows the heterogeneity of the silver iodide distribution but more directly, the aforesaid fact can be clearly concluded from that when the tabular grains are annealed under the condition wherein iodide ions can move in the silver halide crystal (e.g., 250°C, 3 hours), the striped pattern is completely vanished.
  • annular ring-like striped pattern showing the heterogeneity of the silver iodide distribution of the tabular silver iodobromide emulsion grains described above is clearly observed in the transmission type electron microphotograph attached to JP-A-58-113927 cited above and also is clearly shown in the transmission type electron microphotograph in the King et al investigation cited above.
  • the conventional silver iodobromide grains prepared in a definite silver iodide content for obtaining a homogeneous silver iodide distribution have a very microscopically heterogeneous distribution of silver iodide contrary to the inter don for the production thereof and neither the technique for homogenizing the distribution nor the production process for such silver halide grains has been disclosed.
  • the present invention discloses the silver halide emulsion having the completely homogeneous microscopic silver iodide distribution and the production process thereof.
  • the silver halide grains having "the completely hemogeneous silver iodide distribution" can be clearly distinguished from conventional silver halide grains by observing the transmitted images of the grains using the cooling type transmission electron microscope. That is, in the inside of the silver halide grains containing silver iodide of this invention, there exist at most two lines caused by the heterogeneity of silver iodide at an interval of 0.2 pm in the direction crossing the lines, preferably there exist one such line, and more preferably there exists no such a line.
  • the lines constituting the annular ring-like striped pattern showing the microscopic heterogeneity of silver iodide occur in the form of crossing the growing direction of the grains, which results in concentrically distributing these lines from the center of the grains.
  • the lines constituting the annular ring-like striped pattern showing the heterogeneity of silver iodide rectangularly cross the growing direction of the tabular grains, whereby the lines become parallel to the edge -of the grain, the direction rectangularly crossing the line directs to the center of the grain, and the lines distribute concentrically around the center of the grains.
  • the boundary line can be observed as a similar line to above by the aforesaid observation method but such a change of the content of silver iodide constitutes a single line only and can be clearly distinguished from those constituted by plural lines caused by the microscopic heterogeneity of silver iodide. Furthermore, the line originated in the change of the content of silver iodide can be clearly confirmed by measuring the content of silver iodide at both sides of the line by the analytical electron microscope described above. Such a line by the change of the content of silver iodide is utterly different from the lines originated in the microscopic heterogeneity of silver iodide and shows "a macroscopic silver iodide distribution".
  • the aforesaid line of showing the macroscopic change of the content of silver iodide is not observed since there is not abrupt change of the content of silver iodide and thus if there are at least three lines with an interval of 0.1 pm, it shows that there is the microscopic heterogeneity of the content of silver iodide.
  • the silver halide grains having a completely homogeneous silver iodide distribution are grains having at most two lines, preferably one line, more preferably no line showing the microscopic silver iodide distribution with an interval of 0.2 ⁇ m in the direction of rectangularly crossing the line in the transmitted images of the grain obtained by using a cooling type transmission electron microscope. Furthermore, it is preferred that the grains account for at least 60 % , preferably at least 80 % , and more preferably at least 90% of the whole grains.
  • silver halide grains which are called silver halide grains containing, for example, homogeneous silver iodide are prepared by simply adding silver nitride and a mixture of halides having a definite composition (a definite content of iodide) to a reaction vessel by a double jet method at the growth of grains and thus in such grains, the macroscopic silver iodide distribution may be surely constant but the microscopic silver iodide distribution is not homogeneous.
  • such grains are called as grains having "a constant halogen composition" and are clearly distinguished from the grains of this invention showing "the complete homogeneity".
  • the process of this invention is very effective in the production of pure silver bromide or pure silver chloride.
  • a conventional production process the local existence of silver ions and halogen ions in a reaction vessel is unavoidable and silver halide grains in the reaction vessel are brought into other circumstance than other homogeneous portions by passing through such a local heterogeneous portion, whereby not only the growth thereof becomes heterogeneous but also reduced silver or fogged silver is formed at the portion of a high silver ion concentration. Accordingly, there is no heterogeneous distribution of halide in silver bromide or silver chloride but another heterogeneity as described above occurs. This problem is completely solved by the process of this invention.
  • silver bromide, silver iodobromide, silver iodochlorobromide, or silver chlorc romide can b- used.
  • the preferred silver halide in this invention is silver iodobromide having a silver iodide content of from 3 mol% to 40 mol%, silver chlorobromide, silver chloroiodide, or silver chloroiodobromide.
  • silver iodobromide having a silver iodide content of less than 3 mol% the feature of the "completely homogeneous" mixed crystals by the process of this invention is less.
  • mixed crystals containing silver chlorobromide, silver chloroiodide, or silver chloroiodobromide have a high solubility and are liable to become heterogeneous, the feature of the "completely homogeneous" mixed crystals by the process of this invention is liable to occur.
  • the silver halide grains for use in this invention can be selected from normal crystals containing no twin plane and the examples of crystals described in Shashin Koqyo no Kiso; Ginen Shashin Hen (The Bases of photographic Industry; Silver Salt Photoqraphy), page 163, edited by Nippon Shashin Gakkai (published by Corona Sha), such as single twin having one twin plane, parallel multiple twin having at least 2 parallel twin planes, non-parallel multiple twin having at least 2 non-parallel twin planes, etc., according to the purpose.
  • the (hll) plane grains such as (211) plane grains, the (hhl) plane grains such as (331) plane grains, the (hkO) plane grains such as (210) plane grains, or the (hkl) plane grains such as (321) plane grains reported in Journal of Imaging Science, Vol. 30, page 247, (1986) can be used according to the purpose although some modification is required in the preparation process thereof.
  • Tetradecahedral grains having both a (100) plane and a (111) plane in one grain grains having both a (100) plane and a (110) plane, or grains having both a (111) plane and a (110) plane can be also used according to the purpose.
  • the grain sizes of the silver halide obtained may be fine grains of not more than 0.1 micron or large size grains up to 10 microns in the diameter of the projected area, and also the emulsion may be a mono-dispersed emulsion having a narrow distribution or a polydispersed emulsion having a broad distribution.
  • a so-called mono-dispersed silver halide emulsion having such narrow grain size distribution that at least 80% of the whole grains are within ⁇ 30 % of the mean grain size by number or by weight can be used in this invention.
  • two or more kinds of mono-dispersed silver halide emulsions each having different grain sizes can be used in a same emulsion layer as a mixture thereof or may be coated as double layers.
  • polydispersed silver halide emulsions can be used as a mixture or double layers or a combination of a mono-dispersed emulsion and a polydispersed emulsion can be used as a mixture or double layers.
  • the photographic emulsion of this invention is prepared by the aforesaid process but may be partially prepared by a conventional process.
  • the whole grains may be prepared by the process of this invention or the process of this invention is applied for preparing a part of the grains and remaining grains may be prepared by a conventional process.
  • the core or the shell only of core/shell type silver halide grains having a different halogen composition between the inside and the surface layer of the grain is prepared by the process of this invention and the other may be prepared by a known process or a combination of the process of this invention and a conventional process may be used for the preparation of the inside and the surface layer having a same halogen composition.
  • the preparation of the host and the preparation of the guest may be separately performed by the process of this invention and a conventional process, respectively.
  • the photographic emulsion layers of the photographic light-sensitive material of this invention may contain a photographic emulsion which is not prepared by the production process of this invention.
  • a photographic emulsion can be prepared by the process described in P. Glafkides, Ciemie et Physique Photographique, published by Paul Montel, 1967, G.F. Duffin, Photographic Emulsion Chemistry, published by Focal Press, 1966, and V.L. Zelikman et al, Making and Coating Photographic Emulsion, published by Focal Press, 1964.
  • an acid process, a neutralization process, an ammonia process, etc. can be used and as a system of reacting a soluble silver salt and a soluble halide, a single jet process, a double jet process or a combination thereof may be used.
  • a so-called reverse mixing process of forming silver halide grains in the existence of excess silver ions can be also used.
  • a so-called controlled double jet process of keeping a constant pAg in a liquid phase of forming silver halide grains can be also used. According to the process, a silver halide emulsion containing silver halide grains having a regular crystal form and almost uniform grain sizes can be obtained.
  • the aforesaid silver halide emulsion composed of regular grains is obtained by controlling pAg and pH during the formation of the grains.
  • the details thereof are described, for example, in Photoqraphic Science and Enqineerinq, Vol. 6, pages 159-165 (1962), Journal of Photographic Science, Vol. 12, pages 242-251 (1964), U.S. Patent 3,655,394, and British Patent 1,413,748.
  • tabular grains having an aspect ratio of at least 3 can be used in this invention.
  • the tabular grains can be easily prepared by the methods described in Cleve, Photographic Theory and Practice, page 131 (1930), Gutoff, Photographic Science and Enqineerinq, Vol. 14, pages 248-257 (1970), U.S. Patents 4,434,226, 4,414,310, 4,433,048, and 4,439,520 and British Patent 2,112,157.
  • the tabular grains there are advantages of increasing covering power, increasing the color sensitizing efficiency by sensitizing dyes, etc., as described in detail in U.S. Patent 4,434,226 cited above.
  • a tabular grain silver halide emulsion is preferred.
  • tabular grains wherein grains having an aspect ratio of from 3 to 8 account for at least 50% of the whole projected areas are preferred.
  • the crystal structure may be uniform, differs in halogen composition between the inside and the outer portion thereof, or a layer structure.
  • emulsion grains are disclosed in British Patent 1,027,146, U.S. Patents 3,505,068 and 4,444,877 and Japanese Patent Application 58-248469.
  • silver halides each having different composition may be junctioned to each other by an epitaxial junction or a silver halide may be junctioned to other compound than silver halide, such as silver rhodanate, lead oxide, etc.
  • the silver halide emulsion of this invention has a distribution or a structure in regard to the halogen composition in the grains thereof.
  • the typical ones are core/shell type or double layer structure type grains having a different halogen composition between the inside and the surface layer thereof as disclosed in JP-B-43-13162 and JP-A-61-215540, JP-A-60-222845, and JP-A-61-75337.
  • the form of the core portion is same as the form of the whole grain having shell thereon in one case and is different from the whole grain in another case.
  • the core portion has a cubic form and the form of the whole grain having the shell is cube or octahedron.
  • the form of the core portion is octahedron and the form of the whole grain having the shell is cube or octachedron.
  • the core portion is a clear regular grain and the whole grain having the shell is slightly deformed or is amorphous.
  • the core/shell grains of this invention may have not only a simple double structure but also a triple or more structure as disclosed in JP-A-60-222844 or a structure formed by attaching a thin silver halide layer having a different composition to the surface of the grain having a core/shell structure.
  • grains having not only the aforesaid wrapping structure but also a so-called junction structure can be formed. Examples thereof are disclosed in JP-A-59-133540, JP-A-58-108526, EP 199290A2, JP-B-58-24772, and JP-A-59-16254.
  • the crystals being junctioned can be junctioned to the edge or corner portions or the place portions of host crystals with a different composition from that of the crystals becoming the host.
  • Such junction crystals which can be formed may be homogeneous in halogen composition or have a core/shell type structure.
  • junction structure a combination of silver halides each other can be as a matter of course employed but a combination of silver halide and other silver salt compound having no rock salt structure, such as silver rhodanate, silver carbonate, etc., can be employed as the junction structure. Also, a non-silver salt compound such as PbO can be used if junction structure is possible.
  • the silver iodobromide grains having such a structure in, for example, core/shell type grains the silver iodide content of the core portion may be high and the silver iodide content of the shell portion may be low, or on the contrary the silver iodide content of the core portion may be low and that of the shell portion may be high.
  • the silver iodide content may be higher in the host crystal and relatively lower in the junction crystal or the relation may be the contrary.
  • the boundary portion between the portions of the grain having the aforesaid structure, said portions each having different halogen composition may form a clear boundary, may form an uncertain boundary by forming mixed crystals by the difference in halogen composition, or may have a continuously changing structure positively formed.
  • the silver halide emulsion for use in this invention may be subjected to the treatment of providing roundness to the grains as disclosed in EP 0096727 Bl and EP 0064412 Bl or the surface modification treatment as disclosed in DE 2306447 C2 and JP-A-60-221320.
  • the silver halide emulsion for use in this invention is preferably of a surface latent image type but an internal latent image type emulsion can be used by selecting a suitable developer or a suitable development condition as disclosed in JP-A-59-133542. Also, a shallow internal latent image type emulsion having covered thereon a thin shell can also be used according to the purposes.
  • a chemical sensitization such as a reduction sensitization, a sulfur sensitization, and a gold sensitization.
  • the portion being chemically sensitized differs according to the composition, structure, and form of the emulsion grains or the purpose of using the emulsion.
  • There is a case of forming the chemically sensitized nucleus in the inside of the grain the case of forming the chemically sensitized nucleus in the position near the surface of the grain, or the case of forming the chemically sensitized nucleus at the surface thereof.
  • the present invention is effective for any case described above but the case of forming the chemically sensitized nucleus in the vicinity of the surface is particularly preferred.
  • the surface latent image type emulsion is more effective than the internal latent image type emulsion in this invention.
  • the chemical sensitization can be carried out using active gelatin as described in T.H. James, The Theory of the Photographic Process, 4th ed., pages 67-76 (1977), MaCmillan and also can be carried out using sulfur, selenium, tellurium, gold, platinum, palladium, iridium, or a combination of these sensitizers at pAg of from 5 to 10, pH of from 5 to 8, and a temperature of from 30 to 80°C as described in Research Disclosure, Vol. 120, 12008, (April, 1974); Research Disclosure, Vol. 34, 13452, (June, 1975), U.S.
  • the chemical sensitization is most favorably carried out in the existence of a gold compound and a thiocyanate compound or in the existence of the sulfur-containing compound described in U.S. Patents 3,857,711, 4,266,018, and 4,054,457 or a sulfur-containing compound such as hypo, thiourea compounds, rhodanine compounds, etc.
  • the chemical sensitization can be carried out in the existence of a chemical sensitization aid.
  • the chemical sensitization aid a compound which is known to inhibit the formation of fog and increase the sensitivity in the step of the chemical sensitization, such as an azaindene, azapyridazine, and azapyrimidine is used.
  • Examples of the chemical sensitization aid are described in U.S. Patents 2,131,038, 3,411,914, and 3,554,757, JP-A-58-126526, and C.F. Duffin, Photographic Emulsion Chemistry, published by Focal Press, 1966, pages 138-143.
  • the formation of fog by the reaction of reduced silver nuclei and the gold salt by the addition of the aforesaid oxidizing agent and/or the inhibitor prior to the formation of grains in the domain it is preferred that the formation of the grains in the domain of at least 0.001 ⁇ m from the surface of the grain is carried out in the existence of the oxidizing agent and/or the inhibitor.
  • the photographic emulsion for use in this invention can contain various kinds of compounds for inhibiting the formation of fog during the production, the storage, or photographic processing of the light-sensitive materials or stabilizing the photographic performance thereof. That is, there are many compounds known as antofiggants or stabilizers, such as azoles (e.g., benzothiazolium salt, nitroimidazoles, nitrobenz- imidazoles, chlorobenzimidazoles, bromobenzimidazoles, mercaptothiazoles, mercaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, aminotriazoles, benzotriazole, nitrobenzotriazoles, mercaptotetrazoles (in particular, I-phenyl-5-mercaptotetrazole), etc.), mercaptopyrimidines, mercaptotriazines, thioketo compounds (e.g., oxazolinethione), azaindenes (
  • the silver halide emulsions for use in this invention may be spectrally sensitized by methine dyes, etc.
  • the dyes for use include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes, and hemioxonol dyes.
  • Particularly useful dyes are dyes belonging to cyanine dyes, merocyanine dyes, and complex merocyanine dyes.
  • nuclei ordinarily utilized for cyanine dyes as basic heterocyclic nuclei. That is, pyrroline nuclei, oxazoline nuclei, thiazoline nuclei, pyrrole nuclei, oxazole nuclei, thiazole nuclei, selenazole nuclei, imidazole nuclei, tetrazole nuclei, pyridine nuclei, etc.; the nuclei formed by fusing an aliphatic hydrocarbon ring to the aforesaid nuclei; and the nuclei formed by fusing an aromatic hydrocarbon ring to the aforesaid nuclei, such as indolenine nuclei, benzindolenine nuclei, indole nuclei, benzoxazole nuclei, naphthoxazole nuclei, benzothiazole nuclei, naphthothiazole nuclei, benzoselenazo
  • merocyanine dyes or complex merocyanine dyes may be applied 5-memberd or 6-membered heterocyclic nuclei such as pyrazoline-5-one nuclei, thiohydantoin nuclei, 2-thiooxazolidine-2,4-dione nuclei, thiazolidine-2,4-dione nuclei, rhodanine nuclei, thiobarbituric acid nuclei, etc., as a nucleus having a ketomethylene structure.
  • 5-memberd or 6-membered heterocyclic nuclei such as pyrazoline-5-one nuclei, thiohydantoin nuclei, 2-thiooxazolidine-2,4-dione nuclei, thiazolidine-2,4-dione nuclei, rhodanine nuclei, thiobarbituric acid nuclei, etc.
  • sensitizing dyes may be used singly or as a combination thereof.
  • a combination of sensitizing dyes is frequently used for the purpose of super-color sensitization.
  • Typical examples of the combinations are described in U.S. Patents 2,688,545, 2,977,229, 3,397,060, 3,522,052, 3,527,641, 3,617,293, 3,628,964, 3,616,480, 3,672,898, 3,679,428, 3,703,377, 3,769,301, 3,814,609, 3,837,862, and 4,026,707, British Patents 1,344,281 and 1,507,803, JP-B-43-4936 and JP-B-53-12375, and JP-A-52-110618 and JP-A-52-109925.
  • the emulsion may contain a dye having no spectral sensitizing activity by itself or a material which does not substantially absorb visible light and shows super color sensitizing activity together with the sensitizing dye(s).
  • the sensitizing dye(s) may be added to the silver halide emulsion in any step of the preparation of the emulsion, which is known to be useful. Most usually, the addition thereof is performed after the completion of the chemical sensitization and before coating but the sensitizing dye may be added simultaneously with the addition of a chemical sensitizer to perform simultaneously the spectral sensitization and the chemical sensitization as described in U.S. Patents 3,628,969 and 4,225,666, the spectral sensitization can be performed prior to the chemical sensitization as described in JP-A-58-113928, or the spectral sensitization can be initiated by adding the sensitizing dye before the completion of the formation of the precipitation of the silver halide grains.
  • the aforesaid compounds can be dividedly added, that is, a part of these compounds may be added prior to the chemical sensitization and the residues may be added after the chemical sensitization as disclosed in U.S. Patent 4,225,666, or the method disclosed in U.S. Patent 4,183,756 may be used as well as the compounds may be added in any step of forming the silver halide grains.
  • the addition amount can be from 4 x 10-6 to 8 x 10-3 mol per mol of silver halide and in the more preferred case that the size of the silver halide grains is from 0.2 to 1.2 ⁇ m, the effective addition amount is from about 5 x 10-5 to 2 x 10-3 mol.
  • Fig. 1 is a schematic view showing an emulsion reaction vessel which can be used for the process of this invention.
  • Fig. 2 is the detailed view showing a mixer which can be used for this invention.
  • Fig. 3 is a transmission type electron microphotograph showing the crystal structure of conventional tabular silver halide grains having not completely homogeneous iodide distribution of silver iodobromide phase.
  • the emulsion formed was cooled to 35°C, washed with water by an ordinary flocculation method, and after dissolving therein 60 g of gelatin at 40°C, pH and pAg thereof were adjusted to 6.5 and 8.6, respectively.
  • the tabular silver bromide grains were mono-dispersed tabular grains having a mean diameter corresponding to circle of 1.4 ⁇ m, a grain thickness of 0.2 ⁇ m, and a coefficient of variation of circle-corresponding diameters of 15%.
  • Emulsions I-C to I-R thus prepared was added a spectral sensitizing dye 5-chloro-5'-phenyl-3,3'-(3-sulfopropyl)-9-ethyloxacarbocyanine (240 mg/mol-Ag and after adding thereto sodium thiosulfate (8 x 10-6 mol/mol-Ag), the emulsion was most favorably chemically sensitized at 60°C. After finishing the chemical sensitization, 100 g of each emulsion (containing 0.08 mol of Ag) was dissolved at 40°C and following additives (1) to (4) were successively added thereto with stirring.
  • a coating composition for surface protective layer was prepared by successively adding following components
  • Both the emulsion coating composition and the coating composition for surface protective layer thus obtained were coated on a polyethylene terephthalate film support by a simultaneous extrusion method at a volume ratio of 103 : 45 at coating.
  • the coated silver amount was 3.1 g/m2.
  • Samples 114 to 116 using the emulsions the reduction sensitization of which was carried out in the existence of the oxidizing agent by the process of this invention show almost same fog as Sample 102 using the emulsion without being reduction sensitized and have very high sensitivity.
  • Emulsions I-C, D, H, K, O and R were prepared and each emulsion was most favorable chemically sensitized at 60°C by adding thereto sodium benzenethiosulfonate (2 x 10-4 mol/mol-Ag), sodium thiosulfate (1 x 10-5 mol/mol-Ag), chloroauric acid (2 x 10-5 mol/mol-Ag), and potassium thiocyanate (3.2 x 10- 4 mol/mol-Ag). After finishing the chemical sensitization, each of the emulsions was coated as in Example 1 to provide Coated Samples 201 to 206.
  • Example 2 Each sample was exposed, processed and tested as in Example 1 except that the yellow filter was not used at the exposure and the results obtained are shown in Table 2.
  • the sensitivity was shown relative values with that of Sample 201 being 100.
  • Sodium benzenethiosulfonate used in this example is a compound belonging to general formula [I] gave almost no influence on the fog and sensitivity of Emulsions I-C and I-D but reduced the fog value without substantially changing the sensitivity on Emulsions I-H, K, O and R. However, when the amount thereof was increased, the fog value was not changed too much.
  • Emulsion 3-A [Comparison Example]
  • an aqueous solution of 1.5M of silver nitrate and an equimolar amount of an aqueous solution of 1.5M of potassium bromide were simultaneously added to the emulsion as the core emulsion to form the shell (2nd coating layer) of silver bromide.
  • the mol ratio of 1st coating layer/2nd coating layer was 1 : 1.
  • the p H of the system at the formation of the shell was kept at 5.8.
  • the emulsion grains obtained were a core/shell mono-dispersed octahedral grains containing 25 mol% silver iodide in the inside having 1.2 ⁇ m in mean circle corresponding diameter.
  • Emulsion 3-B [Comparison Example]
  • the very fine grains formed in the mixer were immediately introduced into the reaction vessel kept at 75°C to form a 1st coating layer.
  • the pH in the system in the reaction vessel was kept at 6.5.
  • an aqueous solution containing 1.5M of silver nitrate, an aqueous solution containing 1.5M of potassium bromide, and an aqueous solution of 2% by weight gelatin were added to the mixer to form the shell (2nd coating layer) of silver bromide, whereby the grains of 1 : 1 in the ratio of 1st coating layer/2nd coating layer were obtained.
  • the pH at the formation of the 2nd coating layer was kept at 5.8.
  • the grains obtained were octahedral mono-dispersed core/shell emulsion grains having a circle corresponding diameter of 1.2 pm.
  • Emulsions 3-C and D were prepared.
  • the grain sizes were almost same.
  • Emulsions 3-E and F were prepared.
  • the grain sizes were almost same.
  • Each of the emulsions obtained as above was most favorably chemically sensitized at 56°C by adding sodium benzenethiosulfonate (2 x 10- 4 mol/mol-Ag), sodium thiosulfate (1.2 x 10-5 mol/mol-Ag), chloroauric acid (1.6 x 10- 5 mol/mol-Ag), and potassium thiocyanate (2.5 x 10- 4 mol/mol-Ag). Then, after adding thereto the following compounds, the emulsion was coated on a triacetyl cellulose film support having subbing layer together with a protective layer by a simultaneous extrusion method.
  • Each of the samples was sensitometerically exposed for 1/100 second through a yellow filter and subjected to the following color development process.
  • the composition of the processing solution used for each step was as follows. Bleaching Solution: Fixing Solution:
  • Samples 305 and 306 of this invention showed low fog and high sensitivity. Furthermore, the samples of this invention showed high gradation as compared with Comparison Samples 301, 303, and 304.
  • Example 5 By following the same procedure as Example 5 in Japanese Patent Application No. 63-7853 while using the emulsion in Example 2 of the present specification and the emulsion in Example 3 of the present specification in place of the emulsions of Layer 5 and Layer 16, respectively, of Example 5, it was confirmed that a photographic light-sensitive material having high sensitivity and giving low fog was obtained.
  • the emulsion formed was washed by an ordinary flocculation method and after dissolving therein 30 g of gelatin, the pH thereof was adjusted to 6.5.
  • the mean grain size of the silver chlorobromide fine grains (silver chloride content 40 mol%) obtained was 0.09 ⁇ m.._
  • 800 cc of an aqueous solution containing 150 g of silver nitrate and 800 cc of an aqueous solution containing 63 g of potassium bromide and 43 g of sodium chloride were simultaneously added to the emulsion by a double jet method over a period of 100 minutes at 75°C.
  • the emulsion was washed with water by an ordinary flocculation method at 35°C and after adding thereto 70 g of gelatin, pH and pAg thereof were adjusted to 6.2 and 7.8, respectively.
  • the pH of the system in the reaction vessel during the formation of the grains was adjusted to 4.5.
  • the grains formed were silver chlorobromide octahedral grains having a mean grain size of 1.5 ⁇ m and containing 40 mol% silver chloride.
  • Emulsion 5-B silver chlorobromide nucleus grains having a mean grain size of 0.3 ⁇ m were obtained and then fine grain emulsion 5-A (silver chloride content 40 mol%) dissolved at 7 5°C were added to the reaction vessel by a pump.
  • the fine grain emulsion was added over a period of 100 minutes such that the amount thereof became 150 g calculated as silver nitrate.
  • 20 g of sodium chloride was previously dissolved in the fine grain emulsion.
  • the emulsion was washed with water as in the case of Emulsion 5-B and pH and pAg thereof were adjusted to 6.5 and 7.8, respectively at 40°C.
  • the pH in the reaction vessel during the formation of the grains was adjusted to 4.5.
  • the grains obtained were silver chlorobromide octahedral grains having a mean grain size of 1.5 ⁇ m and a silver chloride content of 40 mol%.
  • Emulsions 5-D and E were prepared.
  • the addition rates of the aqueous silver nitrate solution and the aqueous halide solution at the nucleus formation were controlled such that the grain size thereof became same as that of Emulsion 5-B.
  • Emulsions 5-F and G were prepared. The grain sizes were adjusted such that they became same as above by controlling the addition rate of the fine grain emulsion.
  • color image stabilizer (c) a stabilizer, 4-hydroxy-6-methyl-l,3,3a,7-tetraazaindene, an antifoggant, 1-[3-(3-methylureido)-phenyl]-5-mercaptotetrazole, a hardening agent, 2,4-dichloro-6-hydroxy-s-triazine sodium, and a coating aid, sodium dodecylbenzenesulfonate
  • the emulsion was coated on a paper support having polypropylene layer laminated on both the surfaces thereof together with a gelatin protective layer.
  • the relative sensitivity was shown by the relative value of the reciprocal of the exposure amount necessary for giving the density of fog value +0.5 with that of Sample 501 in development time of 3 minutes 30 seconds being defined as 100.
  • Samples 505 and 506 had a high sensitivity as compared to the comparison samples and were suitable for quick processing owing to the small deviation in photographic performance by development time.
  • Comparison Samples 501, 503, and 504 using the emulsions the grain growth of which was carried out by the addition of the aqueous silver nitrate solution and the aqueous halide solution showed large deviation in photographic performance by development time and also Samples 503 and 504 caused severe fog formation.
  • the photographic light-sensitive materials obtained by the process of this invention has high sensitivity, gives less fog, and show good graininess.

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  • Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)

Abstract

Ce matériau photographique présente une couche constituée par une émulsion d'halogénure d'argent contenant des granules d'halogénure d'argent photosensibles que l'on obtient en ajoutant de fins granules d'halogénure d'argent préparés d'avance dans un récipient de réaction pour former des noyaux de granules et/ou cultiver des cristaux de manière à former des noyaux et/ou laisser les cristaux se développer dans le récipient de réaction et en les soumettant à une sensibilisation par réduction. Ce matériau présente une grande sensibilité, moins de voile et de bonnes caractéristiques de grain.
EP89901593A 1988-01-18 1989-01-18 Materiau photographique a base d'halogenure d'argent et procede de preparation Withdrawn EP0407576A1 (fr)

Applications Claiming Priority (12)

Application Number Priority Date Filing Date Title
JP785288A JPH01183644A (ja) 1988-01-18 1988-01-18 ハロゲン化銀写真乳剤
JP63007851A JPH0723218B2 (ja) 1988-01-18 1988-01-18 ハロゲン化銀粒子の製造方法
JP7852/88 1988-01-18
JP7853/88 1988-01-18
JP7851/88 1988-01-18
JP63007853A JPH07104569B2 (ja) 1988-01-18 1988-01-18 ハロゲン化銀写真乳剤
JP194862/88 1988-08-04
JP194861/88 1988-08-04
JP63194861A JPH0769580B2 (ja) 1988-08-04 1988-08-04 ハロゲン化銀写真乳剤
JP63194862A JPH0778600B2 (ja) 1988-08-04 1988-08-04 ハロゲン化銀写真乳剤
JP195778/88 1988-08-05
JP63195778A JPH0782208B2 (ja) 1988-08-05 1988-08-05 ハロゲン化銀の製造方法

Publications (2)

Publication Number Publication Date
EP0407576A4 EP0407576A4 (fr) 1990-08-09
EP0407576A1 true EP0407576A1 (fr) 1991-01-16

Family

ID=27548083

Family Applications (2)

Application Number Title Priority Date Filing Date
EP89901593A Withdrawn EP0407576A1 (fr) 1988-01-18 1989-01-18 Materiau photographique a base d'halogenure d'argent et procede de preparation
EP89908140A Expired - Lifetime EP0370116B1 (fr) 1988-01-18 1989-01-18 Materiau photographique a base d'halogenure d'argent et procede de preparation

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP89908140A Expired - Lifetime EP0370116B1 (fr) 1988-01-18 1989-01-18 Materiau photographique a base d'halogenure d'argent et procede de preparation

Country Status (3)

Country Link
EP (2) EP0407576A1 (fr)
DE (1) DE68924693T2 (fr)
WO (2) WO1989006831A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0696757A2 (fr) 1994-08-09 1996-02-14 Eastman Kodak Company Film pour la duplication d'images d'argent dans des films radiographiques
EP0374954B1 (fr) * 1988-12-22 1997-05-28 Fuji Photo Film Co., Ltd. Procédé de contrÔle et appareil pour la formation des granules à l'halogénure d'argent
EP0374852B1 (fr) * 1988-12-19 1998-03-25 Fuji Photo Film Co., Ltd. Procédé pour former des grains à l'halogénure d'argent
EP0843209A1 (fr) 1996-11-13 1998-05-20 Imation Corp. Procédé de préparation d'une émulsion à l'halogénure d'argent

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2704456B2 (ja) * 1990-08-28 1998-01-26 富士写真フイルム株式会社 ハロゲン化銀乳剤の製造方法
US5273871A (en) * 1990-10-03 1993-12-28 Konica Corporation Silver halide photographic emulsion and silver halide color photographic light-sensitive material incorporating it
US5173398A (en) * 1990-10-31 1992-12-22 Konica Corporation Silver halide color photographic light-sensitive material
JP2936105B2 (ja) * 1991-06-06 1999-08-23 コニカ株式会社 ハロゲン化銀乳剤の製造方法及びハロゲン化銀写真感光材料
US5320938A (en) * 1992-01-27 1994-06-14 Eastman Kodak Company High chloride tabular grain emulsions and processes for their preparation
JP2002323727A (ja) 2001-02-26 2002-11-08 Fuji Photo Film Co Ltd ハロゲン化銀乳剤

Citations (3)

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Publication number Priority date Publication date Assignee Title
DE1472745A1 (de) * 1965-03-09 1972-02-03 Agfa Gevaert Ag Verfahren zur Herstellung von Silberhalogenid-Dispersionen
FR2169360A1 (fr) * 1972-01-26 1973-09-07 Agfa Gevaert Ag
GB2089056A (en) * 1980-11-11 1982-06-16 Konishiroku Photo Ind A silver halide photographic emulsion

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4921657B1 (fr) * 1970-09-24 1974-06-03
BE894965A (fr) * 1981-11-12 1983-05-09 Eastman Kodak Co Emulsion photographique au bromoiodure d'argent d'indice de forme eleve et procede pour la preparer

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1472745A1 (de) * 1965-03-09 1972-02-03 Agfa Gevaert Ag Verfahren zur Herstellung von Silberhalogenid-Dispersionen
FR2169360A1 (fr) * 1972-01-26 1973-09-07 Agfa Gevaert Ag
GB2089056A (en) * 1980-11-11 1982-06-16 Konishiroku Photo Ind A silver halide photographic emulsion

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of WO8906831A1 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0374852B1 (fr) * 1988-12-19 1998-03-25 Fuji Photo Film Co., Ltd. Procédé pour former des grains à l'halogénure d'argent
EP0374954B1 (fr) * 1988-12-22 1997-05-28 Fuji Photo Film Co., Ltd. Procédé de contrÔle et appareil pour la formation des granules à l'halogénure d'argent
EP0696757A2 (fr) 1994-08-09 1996-02-14 Eastman Kodak Company Film pour la duplication d'images d'argent dans des films radiographiques
EP0843209A1 (fr) 1996-11-13 1998-05-20 Imation Corp. Procédé de préparation d'une émulsion à l'halogénure d'argent
US5972589A (en) * 1996-11-13 1999-10-26 Imation Corporation Silver halide emulsion manufacturing method

Also Published As

Publication number Publication date
EP0370116A4 (en) 1990-09-26
EP0370116A1 (fr) 1990-05-30
WO1989006831A1 (fr) 1989-07-27
EP0407576A4 (fr) 1990-08-09
WO1989006830A1 (fr) 1989-07-27
DE68924693D1 (de) 1995-12-07
EP0370116B1 (fr) 1995-11-02
DE68924693T2 (de) 1996-06-13

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