Light-sensitive silver halide photographic materials
United States Patent 3890154
There is provided a light-sensitive silver halide photographic material comprising at least one layer on a support which comprises a binder containing (i)light-sensitive silver halide grain particles characterized as exhibiting a high surface-sensitivity; (ii) at least one compound containing a Group VIII metal at a level of from 1 × 10-6 to 1 × 10-3 mol per 1 mol of said silver halide (iii) at least one optical sensitizer selected from the group consisting of compounds of the general formula ##SPC1## Wherein Ro, R1, R2, R3, R4, R5, R6, Y1, Y2, X and m are defined hereinafter, and compounds of the general formula ##SPC2## Wherein R8, R9, R10, L1, L2 and Y3 are defined hereinafter.
US Patent References:
Green sensitization for photographic emulsions containing coupler dispersions
Jones et al. - November 1959 - 2912329
Chemically sensitized emulsions having low surface sensitivity and high internal sensitivity
Porter et al. - September 1965 - 3206313
/3672901.html
Ohkubo et al. - June 1972 - 3672901
/3741767.html
Baylis et al. - June 1973 - 3741767
/3761266.html
Milton - September 1973 - 3761266
Green sensitization for photographic emulsions containing coupler dispersions
Jones et al. - November 1959 - 2912329
Chemically sensitized emulsions having low surface sensitivity and high internal sensitivity
Porter et al. - September 1965 - 3206313
/3672901.html
Ohkubo et al. - June 1972 - 3672901
/3741767.html
Baylis et al. - June 1973 - 3741767
/3761266.html
Milton - September 1973 - 3761266
Inventors:
Ohkubo, Kinji (Kanagawa, JA)
Noguchi, Junpei (Kanagawa, JA)
Ohmura, Kunioki (Kanagawa, JA)
Hinata, Masanao (Kanagawa, JA)
Noguchi, Junpei (Kanagawa, JA)
Ohmura, Kunioki (Kanagawa, JA)
Hinata, Masanao (Kanagawa, JA)
Application Number:
05/344401
Publication Date:
06/17/1975
Filing Date:
03/23/1973
View Patent Images:
Export Citation:
Assignee:
Fuji Photo Film Co., Ltd. (Kanagawa, JA)
Primary Class:
Other Classes:
430/524, 430/592, 430/575, 430/523, 430/494
International Classes:
G03C1/08; G03C1/12; G03C1/28; G03C1/08
Field of Search:
96/125,126,137,140,108
Primary Examiner:
Brown, Travis J.
Attorney, Agent or Firm:
Sughrue, Rothwell Mion Zinn And Macpeak
Parent Case Data:
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part application of our earlier co-pending application Ser. No. 101,233 filed Dec. 24, 1970, now abandoned which claims priority from Dec. 24, 1969 and Jan. 9, 1970, respectively, based on Japanese Patent Applications 104009/69 and 2819/70, respectively.
Claims:
What is claimed is
1. A light-sensitive silver halide photographic material comprising at least one layer having high sensitivity to green light under flash exposure on a support which comprises an emulsion consisting essentially of:
2. a binder,
3. light-sensitive silver halide grain particles of homogeneous structure exhibiting high surface sensitivity, compared to core-shell type particles,
4. at least one simple salt or complex salt of a Group VIII metal selected from the group consisting of iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum, and
5. at least one optical sensitizer selected from the group consisting of compounds of the general formula: ##SPC9##
6. The light-sensitive silver halide photographic material of claim 1, wherein said binders are selected from the group consisting of gelatin, polyvinyl alcohol, polyvinyl pyrrolidone, sodium alginate, carboxymethyl cellulose and mixtures thereof.
7. The light-sensitive silver halide photographic material of claim 1, wherein said support is selected from the group consisting of glass, metal, wood, baryta paper, cellulose acetate film and polyester film.
8. The light-sensitive silver halide photographic material of claim 1, where the aryl group is selected from the group consisting of a phenyl group and a substituted phenyl group whose substituents are selected from the group consisting of a halogen atom and an alkyl group.
9. The light-sensitive silver halide photographic material of claim 1, wherein said optical sensitizers are selected from the group consisting of 5,5',6-trichloro-1,1',3-triethyl-3'-(3-carboxypropyl)-benzimidazole-carboc yanine iodide and 3-allyl-5-[2-(1-ethyl-4-methyl-tetrazolylidene)ethylidene]-rhodamine.
10. The light-sensitive silver halide photographic material of claim 1, wherein said sensitizer is used at a level of from 1 × 10-2 to 1 × 10-5 mol per 1 mol of said silver halide.
11. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is potassium hexacyanoferrate (III) and wherein said optical sensitizer is 5,5',6-trichloro-1,1',3-triethyl-3'-(3-carboxypropyl)-benzimidazole-carboc yanine iodide.
12. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is ammonium hexachloro rhodate (III) and wherein said optical sensitizer is 5,5',6-trichloro-1,1',3-triethyl-3'-(3-carboxypropyl)-benzimidazolo-carboc yanine iodide.
13. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is potassium hexachloroiridate (IV) and wherein said optical sensitizer is 5,5',6-trichloro-1,1',3-triethyl-3'-(3-carboxypropyl)-benzimidazolo-carboc yanine iodide.
14. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is potassium hexacyanoferrate (III) and wherein said optical sensitizer is 3-allyl-5-[2-(1-ethyl-4-methyl-tetrazolylidene)-ethylidene]-rhodanine.
15. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is ammonium hexachlororhodate (III) and wherein said optical sensitizer is 3-allyl-5-[2-(1-ethyl-4-methyl-tetrazolylidene)-ethylidene]-rhodanine.
16. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is potassium hexachloroiridate (IV) and wherein said optical sensitizer is 3-allyl-5-[2-(1-ethyl-4-methyl-tetrazolylidene)-ethylidene]-rhodanine.
17. The light-sensitive silver halide photographic material of claim 1, wherein said R0 represents a member selected from the group consisting of a methyl group and an ethyl group; wherein R7 represents a member selected from the group consisting of a methyl group and an ethyl group; and wherein R3, R4, R5 and R6 each represents a member selected from the group consisting of a methyl group, an ethyl group, a chlorine atom, a bromine atom, a fluorine atom, a methoxy group, an ethoxy group, and a phenyl group.
18. The light-sensitive silver halide photographic material of claim 1, wherein said complex salt is a member selected from the group consisting of a hexagonal complex salt, a tetragonal complex salt, and a square-plane complex salt.
19. The light-sensitive silver halide photographic material of claim 14, wherein said complex salt is an alkali metal or ammonium salt selected from the group consisting of hexacyanoferrate (II), hexacyanoferrate (III), hexachloroiridate (III).
20. The light-sensitive silver halide photographic material of claim 1, wherein said simple salts are rhodium (III) halide or iridium (IV) halide.
21. The light-sensitive silver halide photographic material of claim 4, wherein the alkyl group having a carboxy group in R1 and R2 is a carboxy-(alkoxy)n-1 -alkyl group wherein n is 1 or 2; wherein the alkyl group having a sulfo group in R1 and R2 is selected from a sulfo-(alkoxy)n-1 -alkyl group (n=1, 2 or 3), a hydroxy-sulfo-(alkoxy)n-1 -alkyl group (n=1 or 2) and an acyloxy-sulfo group.
22. The light-sensitive silver halide photographic material of claim 1, wherein the substituted alkyl group in R1 and R2 is selected from the group consisting of a beta-hydroxyethyl group, a beta-acetoxyethyl group, a carboxymethyl group, a beta-carboxyethyl group, a gamma-carboxypropyl group, a 2-(2-carboxyethoxy)ethyl group, a beta-sulfoethyl group, a gamma-sulfopropyl group, a delta-sulfobutyl group, a 2-hydroxy-1-sulfopropyl group, a 2-(3-sulfopropoxy)ethyl group, a 2-acetoxy-1-sulfopropyl group, a 3-methoxy-2-(3-sulfopropoxy)propyl group, a 2-[2-(3-sulfopropoxy)ethoxy]ethyl group and a 2-hydroxy-3-(3-sulfopropoxy)-propyl group; wherein the substituted alkyl group in R8, R9 and R10 is selected from the group consisting of a carboxymethyl group, a beta-hydroxyethyl group, a beta-sulfoethyl group and a gamma-sulfopropyl group.
23. The light-sensitive silver halide photographic material of claim 1 wherein the optical sensitizer and the simple or complex salt is selected from the following combination systems:
24. The light-sensitive silver halide photographic material of claim 1, wherein flash exposure is exposure to the afterglow of the fluorescence of a cathode ray tube or a xenon flash lamp for time ranging from 1/10,000,000 of a second to 1/100,000 of a second.
25. A photographic recording process which comprises exposing to a flash light the silver halide photographic material comprising at least one layer having high sensitivity to green light under flash exposure on a support which comprises an emulsion consisting essentially of:
26. a binder,
27. light-sensitive silver halide grain particles of homogeneous structure exhibiting high surface sensitivity, compared to core-shell type particles,
28. at least one simple salt or complex salt of a Group VIII metal selected from the group consisting of iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum, and
29. at least one optical sensitizer selected from the group consisting of compounds of the general formula: ##SPC11##
30. The photographic recording process of claim 20 wherein the photographic material is exposed to a flash light for a time of at most 1 × 10-7 seconds.
31. The photographic recording process as claimed in claim 20 wherein the light-sensitive silver halide particles are formed by a process which comprises forming silver halide precipitates, and further wherein a salt of a Group VIII metal is added at the stage of forming said silver halide precipitate.
1. A light-sensitive silver halide photographic material comprising at least one layer having high sensitivity to green light under flash exposure on a support which comprises an emulsion consisting essentially of:
2. a binder,
3. light-sensitive silver halide grain particles of homogeneous structure exhibiting high surface sensitivity, compared to core-shell type particles,
4. at least one simple salt or complex salt of a Group VIII metal selected from the group consisting of iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum, and
5. at least one optical sensitizer selected from the group consisting of compounds of the general formula: ##SPC9##
6. The light-sensitive silver halide photographic material of claim 1, wherein said binders are selected from the group consisting of gelatin, polyvinyl alcohol, polyvinyl pyrrolidone, sodium alginate, carboxymethyl cellulose and mixtures thereof.
7. The light-sensitive silver halide photographic material of claim 1, wherein said support is selected from the group consisting of glass, metal, wood, baryta paper, cellulose acetate film and polyester film.
8. The light-sensitive silver halide photographic material of claim 1, where the aryl group is selected from the group consisting of a phenyl group and a substituted phenyl group whose substituents are selected from the group consisting of a halogen atom and an alkyl group.
9. The light-sensitive silver halide photographic material of claim 1, wherein said optical sensitizers are selected from the group consisting of 5,5',6-trichloro-1,1',3-triethyl-3'-(3-carboxypropyl)-benzimidazole-carboc yanine iodide and 3-allyl-5-[2-(1-ethyl-4-methyl-tetrazolylidene)ethylidene]-rhodamine.
10. The light-sensitive silver halide photographic material of claim 1, wherein said sensitizer is used at a level of from 1 × 10-2 to 1 × 10-5 mol per 1 mol of said silver halide.
11. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is potassium hexacyanoferrate (III) and wherein said optical sensitizer is 5,5',6-trichloro-1,1',3-triethyl-3'-(3-carboxypropyl)-benzimidazole-carboc yanine iodide.
12. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is ammonium hexachloro rhodate (III) and wherein said optical sensitizer is 5,5',6-trichloro-1,1',3-triethyl-3'-(3-carboxypropyl)-benzimidazolo-carboc yanine iodide.
13. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is potassium hexachloroiridate (IV) and wherein said optical sensitizer is 5,5',6-trichloro-1,1',3-triethyl-3'-(3-carboxypropyl)-benzimidazolo-carboc yanine iodide.
14. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is potassium hexacyanoferrate (III) and wherein said optical sensitizer is 3-allyl-5-[2-(1-ethyl-4-methyl-tetrazolylidene)-ethylidene]-rhodanine.
15. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is ammonium hexachlororhodate (III) and wherein said optical sensitizer is 3-allyl-5-[2-(1-ethyl-4-methyl-tetrazolylidene)-ethylidene]-rhodanine.
16. The light-sensitive silver halide photographic material of claim 1, wherein said compound containing a Group VIII metal is potassium hexachloroiridate (IV) and wherein said optical sensitizer is 3-allyl-5-[2-(1-ethyl-4-methyl-tetrazolylidene)-ethylidene]-rhodanine.
17. The light-sensitive silver halide photographic material of claim 1, wherein said R0 represents a member selected from the group consisting of a methyl group and an ethyl group; wherein R7 represents a member selected from the group consisting of a methyl group and an ethyl group; and wherein R3, R4, R5 and R6 each represents a member selected from the group consisting of a methyl group, an ethyl group, a chlorine atom, a bromine atom, a fluorine atom, a methoxy group, an ethoxy group, and a phenyl group.
18. The light-sensitive silver halide photographic material of claim 1, wherein said complex salt is a member selected from the group consisting of a hexagonal complex salt, a tetragonal complex salt, and a square-plane complex salt.
19. The light-sensitive silver halide photographic material of claim 14, wherein said complex salt is an alkali metal or ammonium salt selected from the group consisting of hexacyanoferrate (II), hexacyanoferrate (III), hexachloroiridate (III).
20. The light-sensitive silver halide photographic material of claim 1, wherein said simple salts are rhodium (III) halide or iridium (IV) halide.
21. The light-sensitive silver halide photographic material of claim 4, wherein the alkyl group having a carboxy group in R1 and R2 is a carboxy-(alkoxy)n-1 -alkyl group wherein n is 1 or 2; wherein the alkyl group having a sulfo group in R1 and R2 is selected from a sulfo-(alkoxy)n-1 -alkyl group (n=1, 2 or 3), a hydroxy-sulfo-(alkoxy)n-1 -alkyl group (n=1 or 2) and an acyloxy-sulfo group.
22. The light-sensitive silver halide photographic material of claim 1, wherein the substituted alkyl group in R1 and R2 is selected from the group consisting of a beta-hydroxyethyl group, a beta-acetoxyethyl group, a carboxymethyl group, a beta-carboxyethyl group, a gamma-carboxypropyl group, a 2-(2-carboxyethoxy)ethyl group, a beta-sulfoethyl group, a gamma-sulfopropyl group, a delta-sulfobutyl group, a 2-hydroxy-1-sulfopropyl group, a 2-(3-sulfopropoxy)ethyl group, a 2-acetoxy-1-sulfopropyl group, a 3-methoxy-2-(3-sulfopropoxy)propyl group, a 2-[2-(3-sulfopropoxy)ethoxy]ethyl group and a 2-hydroxy-3-(3-sulfopropoxy)-propyl group; wherein the substituted alkyl group in R8, R9 and R10 is selected from the group consisting of a carboxymethyl group, a beta-hydroxyethyl group, a beta-sulfoethyl group and a gamma-sulfopropyl group.
23. The light-sensitive silver halide photographic material of claim 1 wherein the optical sensitizer and the simple or complex salt is selected from the following combination systems:
24. The light-sensitive silver halide photographic material of claim 1, wherein flash exposure is exposure to the afterglow of the fluorescence of a cathode ray tube or a xenon flash lamp for time ranging from 1/10,000,000 of a second to 1/100,000 of a second.
25. A photographic recording process which comprises exposing to a flash light the silver halide photographic material comprising at least one layer having high sensitivity to green light under flash exposure on a support which comprises an emulsion consisting essentially of:
26. a binder,
27. light-sensitive silver halide grain particles of homogeneous structure exhibiting high surface sensitivity, compared to core-shell type particles,
28. at least one simple salt or complex salt of a Group VIII metal selected from the group consisting of iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum, and
29. at least one optical sensitizer selected from the group consisting of compounds of the general formula: ##SPC11##
30. The photographic recording process of claim 20 wherein the photographic material is exposed to a flash light for a time of at most 1 × 10-7 seconds.
31. The photographic recording process as claimed in claim 20 wherein the light-sensitive silver halide particles are formed by a process which comprises forming silver halide precipitates, and further wherein a salt of a Group VIII metal is added at the stage of forming said silver halide precipitate.
Description:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to photographic silver halide light sensitive materials. More particularly, the present invention relates to photographic silver halide light sensitive materials having high sensitivity to green light under flash exposure. The term "flash exposure" is defined hereinafter.
2 Description of the Prior Art
The present age is one of information. Various systems have been developed to promote the speedy transmission of information. For instance, press facsimile systems a speedily transmit press manuscripts to distant places, high speed phototypesetting systems expedite printing and typesetting, and cathode ray tube (CRT) display systems represent speedily in letters of figures the information output of computers. With such equipment used for such rapid information transmitting systems, a short time exposure of less than 1/100,000 of a second or especially about 1/1,000,000 of a second is most often used. The demand for sensitive materials to be used for such equipment has in recent years been particularly high.
There are two types of light sources used in connection with these types of equipment, viz., xenon flash lamps and cathode ray tubes. Of these, the one whose fluorescence has an especially short afterglow known generally to be usable for flying spot, is used as the cathode ray tube. For instance, such fluoroscent materials are called "P-11, ""P-15," "P-16" and "P-24" and are used as the light source in question. It is known that the luminous distribution of spectral energy reaches a peak when P-11 reaches 460 nm. and when P-16 reaches 385 nm. This peak corresponds to the region of the spectral absorption characteristic of light sensitive silver halides and hence does not need any optical sensitization. On the other hand, it is known that P-15 has its maximum fluoroscent spectral energy at 505 nm. and for P-24 at 520 nm. The sensitive materials for recording images on CRT must therefore be given sensitivity to green light. On the other hand, a xenon flash lamp emits light over a comparatively broad spectral region. The light from the light source gives images on the sensitive materials through an optical system composed of a condenser lens, a negamatrix, a main lens, a prism, a reflector or a deformation lens or other special lenses, or prisms. The light of short wave length is absorbed to a greater extent by the optics in the path. As a result of the light reaching the sensitive material, the shorter wave length component of from ultraviolet to blue diminishes and the longer wave length component from the green becomes richer. For this reason, green sensitization is indispensable in order to enhance the sensitivity of the sensitive material. The above-described afterglow of the fluorescence of a cathode ray tube ranges from 1/10,000,000 to 1/100,000 of a second and with a xenon flash lamp also one of about the same radiation period is used. In the present invention the short time exposure of these two kinds of light sources described above is generically called flash exsposure.
The conventional sensitizer for green light shows markedly lower spectro sensitization under a flash exposure of 1/100,000 of a second or less in comparison with the result of a conventional exposure of 1/1,000 of a second or longer. Specifically there is a fair indication of this trend where, in order to expedite after exposure the treatments such as fixing or stabilization, silver halide is partly or wholly composed of silver chloride, i.e., a silver chloride emulsion, a chlorobromide emulsion or a chloroiodobromide emulsion.
An object of this inventoin is to provide photographic sensitive materials having high sensitivity to green light under flash exposure.
SUMMARY OF THE INVENTION
This invention provides silver halide light sensitive photographic materials comprising a support on which at least one layer having in the binder (such as gelatin and the like) sensitive silver halide grain particles characterized as exhibiting a high surface sensitivity, at least one compound containing a Group VIII metal of the periodic table at the ratio of from 10 - 6 to 10 - 3 mol per 1 mol of silver halide, and at least one optical sensitizer selected from the group consisting of compounds of the general formula: ##SPC3##
wherein R o represents a hydrogen atom or an alkyl group; wherein R 1 and R 2 each represents a hydrogen atom, an alkyl, a substituted alkyl, an allyl, an aryl or an aralkyl group, in which at least one of R 1 and R 2 must be a carboxyalkyl group or a sulfoalkyl group; wherein Y 1 and Y 2 each represents an oxygen atom, a sulfur atom or a >N--R 7 group in which R 7 is an alkyl group; wherein R 3 ; R 4 , R 5 and R 6 each represents a hydrogen atom, a halogen atom, an alkyl, a cyano, an alkoxy or an aryl group, when at least one of R 3 and R 4 is an aryl group, R 5 and R 6 are not an aryl group; wherein X represents an anion, such as a halogen ion or a thiocyanate ion; and wherein m is 1 or 2, in which an intramolecular salt is formed when m is 1, and compounds of the general formula ##SPC4##
wherein R 8 , R 9 and R 10 each represents a hydrogen atom, an alkyl, a substituted alkyl, an allyl, or an aryl group; wherein Y 3 represents an oxygen atom, a sulfur atom or a >N--R 11 group, in which R 11 is a hydrogen atom, an alkyl or an aryl group; wherein L 1 and L 2 each represents the atoms of a methine chain.
DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The accompanying drawing shows the light transmittance of a glass filter V-Y50 used in the examples in evaluating the effectiveness of the light sensitive photographic materials.
DETAILED DESCRIPTION OF THE INVENTION
More particularly, the present invention is described in greater detail as follows.
For supports, glass plates, metal plates, wooden plates, baryta papers, photographic papers, cellulose acetate film bases, polyester film bases can be used.
Suitable binders are water soluble, film forming high molecular weight compounds such as gelatin, polyvinyl alcohol, polyvinyl pyrollidone, sodium alginate, carboxymethyl cellulose. The binders can be used either individually or in combination.
As the light sensitive silver halide, silver chloride, silver bromide, silver chlorobromide, silver iodobromide, silver chloroiodobromide, can be used. The so-called preparation of the sensitive silver halide emulsion, that is, the preparing of the silver halide crystal grains in the binder in a dispersive state, and making them grow into the proper crystal size thus preparing the silver halide emulsion, can be done by conventional techniques.
With respect to the light sensitive silver halide particles employed in the present invention, it must be emphasized that these particles are characterized as exhibiting a high surface sensitivity. Therefore, the silver halide particles of this invention are quite different from particles of the core-shell type, which exhibit low surface sensitivity and high internal sensitivity.
The metals belonging to Group VIII of the periodic tables are iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, platinum. Examples of the compounds containing these metals desirably used in this invention contain a single salt, or a hexagonal complex, tetragonal complex, or square-plane complex of an alkali metal or ammonium such as ferrous sulfate (FeSO 4 .5H 2 O); ferric chloride (FeCl 3 ); potassium hexacyanoferrate (II)(K 4 ]Fe(CN) 6 ] .3H 2 O); potassium hexacyanoferrate (III)(K 3 ]FeCN 6 ]); cobalt (II) chloride (CoCl 2 ); cobalt (II) nitrate (Co[NO 3 ] 2 6 H 2 O); potassium hexacyanocobaltate (III) (K 3 [Co(CN) 6 ]); nickel (II) chloride (NiCl 2 .6H 2 O); nickel (II) nitrate (Ni[NO 3 ] 2 .6H 2 O); ruthenium chloride (RuCl 3 );potassium hexachlororuthenate (IV) (K 2 RuCl6); rhodium (III) chloride (RhCl 3 .4H 2 ); ammonium hexachlorohodate (III) ([NH 4 ] 3 RhCl 6 ): palladium nitrate (Pd[BO 3 ] 2 ); palladium bromide (PdBr 2 ); potassium hexachloropalladate (IV) (K 2 PdCl 6); potassium tetrathiocyanopalladate (II) (K 2 Pd[CNS] 4 ); osmium (II) chloride (OsCl 2 ); iridium (III) chloride (IrCl 3 ); iridium (IV) chloride (IrCl 4 ); iridium (III) bromide (IrBr 3 .4H 2 O); iridium (IV) bromide (IrBr 4 ); potassium hexachloroiridate (III) (K 3 IrCl 6 ;) potassium hexachloroiridate (IV) (K 2 IrCl 6 ); ammonium hexachloroplatinate (IV) ([NH 4 ] 2 PtCl 6 ); potassium hexachloroplatinate (IV) (K 2 PtCl 6 ); ammonium hexabromoplatinate (IV) ([NH 4 ] 2 PtBr 6 ).
These metallic compounds of Group VIII are used either singly or in combinations of two or more compounds together in the silver halide emulsion in a quantity corresponding from 10 - 6 mol to 10 - 3 mol, preferably 10 - 5 to 3 × 10 - 4 , per 1 mol of silver halide. The addition of these compounds in the emulsion can be made suitably at various stages in the preparation, viz., at the formation of silver halide grain particles in the preparation of silver halide emulsion added either in the halide solution or in the dispersive gelatin solution, or at the beginning of the ripening of the emulsion or at intermediate steps. Also, the compound can be added together with other various prior well known stabilizers, antifoggants, antibronzing agents, surface active agents, hardeners, plasticizers, matting agents, development accelerators or brightening agents and the like as desired, prior to the coating of the emulsion.
One of the optical sensitizers in the present invention is the compound having the following general formula: ##SPC5##
wherein R 0 represents a hydrogen atom or an alkyl group having from 2 to 3 carbon atoms, such as a methyl group, an ethyl group and the like; wherein R 1 and R 2 each represents hydrogen or an alkyl group having from 1 to 4 carbon atoms, such as a methyl group, an ethyl group or propyl group and the like, a substituted alkyl group of the type usually used as an N-substituent of a cyanine dye such as a hydroxyalkyl group (e.g., β-hydroxethyl), an acetoxyalkyl group (e.g., β-acetoxyethyl), an alkyl group having a carboxy group such as a carboxy-(alkoxy) n -1 -alkyl group wherein n is 1 or 2 (e.g., carboxymethyl, β-carboxyethyl, γ-carboxypropyl, 2-(2-carboxyethoxy) ethyl), an alkyl group having a sulfo group such as a sulfo -(alkoxy) n -1 -alkyl group wherein n is 1, 2 or 3, a hydroxysulfo-(alkoxy) n -1 -alkyl group wherein n is 1 or 2 or an acyloxysulfoalkyl group (e.g., β-sulfoethyl, γ-sulfopropyl, δ-sulfobutyl, 2-hydroxyl-1-sulfopropyl, 2-(3-sulfopropoxy)ethyl, 2-acetoxy-1-sulfopropyl, 3-methoxy-2-(3-sulfopropoxy)propyl, 2-]2-(3-sulfopropoxy) ethoxy]ethyl, 2-hydroxy-3-(3-sulfopropoxy)propyl, and the like, an aryl group such as phenyl group or an aralkyl group, but at least one of R 1 and R 2 is a carboxyalkyl group or a sulfoalkyl group; wherein Y 1 and Y 2 each are an oxygen atom, a sulfur atom or a >N--R 7 group in which R 7 is an alkyl group having from 1 to 3 carbon atoms, such as a methyl group or an ethyl group and the like; wherein R 3 , R 4 , R 5 and R 6 each represents a hydrogen atom, an alkyl group having from 1 to 3 carbon atoms, such as a methyl group or an ethyl group and the like, a halogen atom (such as fluorine, chlorine, bromine), a cyano group, an alkoxy group (such as a methoxy or an ethoxy group) or an aryl such as a phenyl group but when at least one of R 3 and R 4 is an aryl group then neither R 5 nor R 6 is an aryl group; wherein X is an anion such as a halogen ion, a thiocyanate ion, sulfate ion, sulphamate ion, perchlorate ion, p-toluene sulphonate ion, benzensulphonate ion, ethyl sulphate ion, or methyl sulphate ion, and wherein m represents 1 or 2, in which an intramolecular salt is formed when m =1.
Specific compounds of these optical sensitizers are shown as follows: ##SPC6##
These sensitizers are described, for example, in U.S. Pat. Nos. 2,503,776; 2,912,329 and 3,397,060, French Pat. No. 1,108,788 and Japanese Patent Publication No. 14030/69, and the synthesis of these sensitizers is well known by reference to the patentscited above and also to the relevant technical literature.
Other sensitizers used in the present invention have the following general formula: ##SPC7##
where R 8 , R 9 and R 10 each represents a hydrogen atom; an alkyl group having from 1 to 8 carbon atoms, such as a methyl group, an ethyl group, a propyl group, a butyl group; a substituted alkyl group of the type usually used as an N-substituent of a cyanine dye such as a carboxyalkyl group, (e.g., a carboxymethyl group), a hydroxyalkyl group (e.g., a β-hydroxyethyl group), a sulfoalkyl group (e.g., a β-sulfoethyl group, a γ-sulfopropyl group); an allyl group; or an aryl group such as a phenyl group, a substituted phenyl group (for example, substituted with a halogen atom e.g., a chlorine atom, an alkyl group and the like); wherein Y 3 is an oxygen atom, a sulfur atom or a >N--R 11 group, in which R 11 is a hydrogen atom, an alkyl group having from 1 to 8 carbon atoms, or an aryl group (e.g., a phenyl group); wherein L 1 and L 2 in each a methine chain (e.g., =CH--, =C(alkyl)--; =C(aryl)--; wherein examples of the alkyl group and the aryl group are a methyl group and a phenyl group, respectively).
Specific compounds of these sensitizers are as follows: ##SPC8##
These sensitizers are described, for example, in the British Pat. No. 801,275 and the synthesis of these sensitizers is well known by reference to the patent cited above and also to the relevant technical literature.
These optical sensitizers are applied, either singly or in combination of two or more, at a ratio of from 10 - 6 to 10 - 3 mol, preferably 10 - 15 to 3 × 10 - 4 mol, per 1 mol of silver halide in the silver halide emulsion. This addition of the optical sensitizer to the emulsion is the same as with the metal compounds above described. The addition into the emulsion can be made either simultaneously with the metal compound, or separately. The sequence of the addition is immaterial.
Thus, it can be seen that the silver halide light-sensitive photographic material can be made essentially in the same manner as usual except that the above metal compound and optical sensitizer are added and the sensitive material thus prepared can, after flash exposure, be developed and fixed in a conventional manner. Also, the material can be treated in a manner known generally as the diffusion transfer process. Or, by adding beforehand an ample quantity of the developing agent in the light-sensitive layer, the development can be treated by the generally known activator development process (a process by which the light-sensitive material containing a developing agent is developed in a solution which does not contain a developing agent and in which only alkaline material is dissolved).
It has been observed that with light-sensitive materials containing the above-described metal compounds but not containing the optical sensitizers, the sensitivity to the green light is not obtained, although, in some cases, their sensitivity to blue light improves. On the other hand, it is recognized that in the case of the sensitive material not containing the metal compounds but containing only the optical sensitizers, the green light sensitivity is not very high. However, by using these two types of materials simultaneously the green light sensitivity in the flash exposure can be markedly improved.
Specifically, with a silver chloride emulsion, a silver chlorobromide emulsion, or a silver chlorobromoiodide emulsion, if the above sensitizer is used alone, a considerable lowering of the efficiency of spectral sensitization in the flash exposure is experienced. For such emulsions the present invention is particularly useful.
It has long been known that the metal compounds described above show various noticeable effects, and as is shown in U.S. Pat. No. 2,448,060, when hexahalogenoruthenium (III) acid salts, hexahalogenorhodium (IV) acid salts, hexahalogeno osmium (IV) acid salts, hexahalogenoiridium (IV) acid salts, or hexahalogenoplatinum (IV) acid salts are added to a silver halide emulsion at the time of ripening, the sensitivity of this emulsion increases. And further, as is disclosed in U.S. Pat. No. 2,566,745, when these compounds are added additionally to the silver halide emulsion the stability of the sensitive material under high temperatures and humidity improves, and further, as is disclosed in U.S. Pat. No. 2,517,541, potassium hexacyanocobaltate (III) and in FIAT Report No. 360 rhodium trichloride, when this compound is added to a silver halide emulsion the contrast of the image obtained from this emulsion increases.
We have found that the iron compounds make the contrast of the emulsion higher.
The compounds of Group VIII elements in the periodic table are added solely for the objects of this invention, but they can also be used to obtain various photographic effects as described above at the same time. Also, as is shown in British Pat. No. 570,393, one can apply the method of increasing the sensitivity of the emulsion by adding the metal compounds at the time of ripening. In other words, when used as a sensitizer or as a stabilizer or as an additive for increasing contrast, the effect of sensitization to green light is displayed if the above dyes are used together. The efficiency which the usual techniques aim at is not hindered.
The present invention will be illustrated in greater detail by the following examples.
EXAMPLE 1
An ordinary acid process silver chlorobromide emulsion was prepared (containing 30 mol % AgBr) not containing the compounds containing metals of Group VIII of the periodic table (hereinafter simply called metal compounds) and by the same method an emulsion was prepared, and at the time of forming the silver halide grains, ammonium hexachlororhodate (III) was added in a quantity equivalent to 7 × 10 - 6 mol per silver halide 1 mol, and at the after-ripening step, potassium hexachloroplatinate (IV) was added in a quantity corresponding 2 × 10 - 5 mol per silver halide 1 mol and the thus prepared emulsion was similar in sensitivity to the conventional emulsion. Each of these 2 emulsions was divided into two parts. One part was not dye-sensitized. To the other was added Dye I in a quantity of 4 × 10 - 3 mol per 1 mol of silver halide in the emulsion. Next, formaldehyde was added to each of these in a quantity of 2.5 per 100 g of gelatin of the emulsion, and then each was applied to a photographic baryta paper.
Using an EG & G Sensitometer Mark VII and through a colored glass filter V-Y50 (made by Tokyo Shibaura Electric Co., Ltd.) and an optical wedge, the above described samples were each given exposures of 1/100 and of 1/1,000,000 of a second. As is shown in the drawing, the colored glass filter V-Y50 (made by Tokyo Shibaura Electric Co., Ltd.) absorbs the light corresponding to the sensitive spectral region of the unsensitized silver halide and transmits only the light corresponding to the optically sensitized region of greater than about 500 nm. The exposed samples were developed at 20°C for 2 seconds in the following developer: N-Methyl-para-aminophenol 2 g Sodium Sulfite, Anhydrous 30 g Hydroquinone 7 g Sodium Carbonate (Monohydrate) 53 g Potassium Bromide 1.5 g Water up to 1 liter
After fixing, rinsing and drying, the reflective density of the images were measured.
The reciprocal of the light quantity giving a density of 0.5 was set as the sensitivity value, but, since the absolute light quantity through the filter was not measured, the sensitivity was only relative, but in the following table the sensitivities of the same exposure time could be in the corresponding state. The results obtained are shown in the table below.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye I Only 4.9 0.9 Group VIII Metal + Dye I 4.6 3.2 ______________________________________
It was observed that by using the rhodate compound, the platinate compound and Dye (I) the green light sensitivity to flash exposure was increased.
EXAMPLE 2
A silver chlorobromide emulsion (containing 50 mol percent AgBr) was prepared in a neutral medium by a well known process and which does not contain the compounds of a Group VIII metal of the periodic table (hereinafter simply called metal compounds), and one was also prepared by adding hexachlororhodate (III) in a quantity of 3 × 10 - 6 mol per 1 mol of silver halide in the above emulsion at the time of the formation of the silver halide grains, then further after ripening potassium chloroplatinate was added in a quantity of 2 × 10 - 5 mol per silver halide 1 mol. The thus prepared emulsion had about the sensitive as the above-described emulsion. These two emulsions were each divided in two parts. One was left intact.
To the other part was added the Dye X in a quantity of 6 × 10 - 3 mol per 1 mol of silver halide in the emulsion. Next, formaldehyde was added to each of these in the quantity of 2.5 g per 100 g of gelatin of the emulsion, and the emulsion was applied to a photographic baryta paper.
The green light sensitivity was measured for the sample thus obtained in the manner as described in Example 1 and the following results were obtained.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye X Only 12.0 2.7 Group VIII Metal + Dye X 10.5 7.2 ______________________________________
It was observed that by using simultaneously the rhodate salt, the platinate salt and Dye X, the green light sensitivity to the flash exposure was increased.
EXAMPLE 3
A silver chlorobromide emulsion (AgCl 50 mol percent, AgBr 50 mol percent) which does not contain the metal compounds of this invention was prepared in a neutral medium in a conventional manner.
Next, by the same method, at the formation of the silver halide grains, 3 × 10 - 6 mol per 1 mol of silver halide of ammonium hexachlororhodate was added to the emulsion, and then after ripening, platinum (IV) chloride in the quantity of 2 × 10 - 5 mol per silver halide 1 mol was added to prepare an emulsion having a sensitivity similar to that of the emulsion without the metal compounds. To each of these emulsions, as in Example 1, Dye IV at a level of 2 × 10 - 3 mol per 1 mol of silver halide was further added. In addition, 2.5 g of formaldehyde was added per 100 g of gelatin, and the emulsion was applied to a photographic baryta paper. The optical sensitization of the sample obtained was measured in the same manner as described in Example 1. The results obtained are shown in the following table.
______________________________________ 1/100 1/1,000,000 Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye IV Only 12.7 2.9 Group VIII Metal + Dye IV 10.8 7.5 ______________________________________
In this case the effect of using the rhodate compound, the platinate salt and Dye IV together was observed.
EXAMPLE 4
A silver chlorobromide emulsion (AgBr 70 mol percent, AgCl 30 mol percent) which does not contain the metal compounds of this invention was prepared in an ammonium alkali medium in a conventional manner. Next, in the same manner potassium hexacyanoferrate (III) was added in a quantity of 1 × 10 - 5 mol per 1 mol of silver halide of the emulsion at the formation of silver halide grains. To these two emulsions Dye III was added in quantity of 2 × 10 - 5 mol per 1 mol of the silver halide.
Further, formaldehyde in a quantity of 2.5 g per 100 g of gelatin was added and the emulsion was applied to a photographic baryta paper. The sensitivity to green light of the samples thus obtained was measured in the same manner as described in Example 1. The results obtained are shown in the table below.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Alone 0 0 Dye III Alone 63 13 Group VIII Metal + Dye III 68 47 ______________________________________
In this case the combined effect of a Group VIII metal compound and Dye III was observed.
EXAMPLE 5
A silver chlorobromoiodide emulsion (AgBr 70 mol percent, AgCl 29 mol percent, Agl 1 mol percent) which does not contain the metal compounds of this invention was prepared in an ammonium alkali medium using a conventional method. Next, using the same procedure, 4 × 10 - 6 mol per 1 mol of silver halide of potassium hexacyanoferrate (III), 6 × 10 - 8 mol per 1 mol of silver halide of potassium hexachloroiridate (IV), 3× 10 - 7 mol per 1 mol of silver halide of ammonium hexachlororhodate (III) were added at the time of formation of the silver halide grains, and again at the after-ripening 3 × 10 - 6 mol per 1 mol of silver halide of chloroauric acid was added, and prepared an emulsion having a sensitivity similar to that of the ordinary sensitivity.
To this emulsion as well as to the emulsion described above, Dye III in a quantity of 6 × 10 - 3 mol per silver halide 1 mol was added. Further, formaldehyde 2.5 g per 100 g of gelatin was added and the emulsion was applied to a photographic baryta paper. The green light sensitivity of this sample was then measured in the same manner as in Example 1. The results obtained are shown in the table below.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye III Only 177 43 Group VIII Metal + Dye III 111 98 ______________________________________
Also, in this case the effect of the joint application of the Group VIII metal salt and Dye III was observed.
EXAMPLE 6
To the emulsion as used in Example 3 Dye VI was added corresponding to a quantity of 8 × 10 - 3 mol per silver halide 1 mol, and this sample was tested in the same manner as described in Example 1. The results obtained are shown in the table below.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye VI Only 336 77 Group VIII Metal + Dye VI 237 246 ______________________________________
In this case also, the effect of the combined treatment of Group VIII metal salt and Dye VI was observed.
EXAMPLE 7
A silver chlorobromide emulsion (AgCl 50 mol percent, AgBr 50 mol percent) which does not contain the metal compounds of this invention was prepared in an ammonium alkali medium in a conventional manner. Next, using the same procedure, at the formation of the silver halide grains, 1 × 10 - 5 mol per 1 mol of silver halide of potassium hexacyanoferrate (III) was added and the emulsion having a sensitivity similar to that of the emulsion not containing metal compounds was obtained. To each of these emulsions, as described in Example 1, Dye VIII was added in a quantity of 4 × 10 - 3 mol per 1 mol of silver halide. Further, formaldehyde in a quantity of 2.5 g per 100 g of gelatin was added, and the emulsion was applied to a photographic baryta paper. The sensitivity to green light of the thus obtained samples was measured using the same method as used in Example 1 and the following results were obtained.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye VIII Only 48 11 Group VIII Metal + Dye VIII 49 35 ______________________________________
In this case also, the combined effect of the ferrate and the Dye VIII was observed.
EXAMPLE 8
A chloroiodobromide silver halide emulsion (AgBr 70 mol percent, AgCl 29 mol percent, Agl 1 mol percent) was prepared not containing metallic compounds of the present invention, using the conventional ammonium method. To an emulsion of the same composition were added at the formation of silver halide grain particles, 4 × 10 - 6 mol potassium hexacyanoferrate (III) 6 × 10 - 8 mol potassium hexachloroirridate (IV), 3 × 10 - 7 ammonium hexachlororhodate (III) per 1 mol silver halide in the emulsion, and then, at the after-ripening, 3 × 10 - 6 per 1 mol of silver halide of chloroauric acid was added. A sensitivity similar to that of the above-described ordinary emulsion was obtained.
To these emulsions was added Dye VII in a quantity corresponding to 2 × 10 - 3 mol per silver halide 1 mol. Again, to these emulsions was added formaldehyde in a quantity of 2.5 g per 100 g of gelatin to prepare a photographic emulsion which was applied to a photographic baryta paper. The green light sensitivity of the sample was measured in the same manner as in Example 1. The results obtained are shown in the table below.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye VII Only 140 27 Group VIII Metal + Dye VII 100 74 ______________________________________
In this instance also the effect of the combined use of the Group VIII metal salt and Dye VII was observed.
EXAMPLE 9
Dye XVI was added to an emulsion which was the same as used in Example 3 in a quantity of 2 × 10 - 3 mol per 1 mol of silver halide. The emulsion was then treated the same as in Example 3 and tested in the same way as Example 1.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye XVI Only 139 30 Group VIII Metal + Dye XVI 89 79 ______________________________________
In this case also the effect of the combined use of the Group VIII metal salt and Dye XVI was observed.
In all the foregoing Examples, the silver halide particles employed were those which exhibited a homogeneous structure and further, exhibited a high surface sensitivity.
While the present invention has been adequately described in the foregoing specification and Examples included therein, it is readily apparent that various changes and modifications can be made to the same without departing from the spirit and scope thereof.
1. Field of the Invention
The present invention relates to photographic silver halide light sensitive materials. More particularly, the present invention relates to photographic silver halide light sensitive materials having high sensitivity to green light under flash exposure. The term "flash exposure" is defined hereinafter.
2 Description of the Prior Art
The present age is one of information. Various systems have been developed to promote the speedy transmission of information. For instance, press facsimile systems a speedily transmit press manuscripts to distant places, high speed phototypesetting systems expedite printing and typesetting, and cathode ray tube (CRT) display systems represent speedily in letters of figures the information output of computers. With such equipment used for such rapid information transmitting systems, a short time exposure of less than 1/100,000 of a second or especially about 1/1,000,000 of a second is most often used. The demand for sensitive materials to be used for such equipment has in recent years been particularly high.
There are two types of light sources used in connection with these types of equipment, viz., xenon flash lamps and cathode ray tubes. Of these, the one whose fluorescence has an especially short afterglow known generally to be usable for flying spot, is used as the cathode ray tube. For instance, such fluoroscent materials are called "P-11, ""P-15," "P-16" and "P-24" and are used as the light source in question. It is known that the luminous distribution of spectral energy reaches a peak when P-11 reaches 460 nm. and when P-16 reaches 385 nm. This peak corresponds to the region of the spectral absorption characteristic of light sensitive silver halides and hence does not need any optical sensitization. On the other hand, it is known that P-15 has its maximum fluoroscent spectral energy at 505 nm. and for P-24 at 520 nm. The sensitive materials for recording images on CRT must therefore be given sensitivity to green light. On the other hand, a xenon flash lamp emits light over a comparatively broad spectral region. The light from the light source gives images on the sensitive materials through an optical system composed of a condenser lens, a negamatrix, a main lens, a prism, a reflector or a deformation lens or other special lenses, or prisms. The light of short wave length is absorbed to a greater extent by the optics in the path. As a result of the light reaching the sensitive material, the shorter wave length component of from ultraviolet to blue diminishes and the longer wave length component from the green becomes richer. For this reason, green sensitization is indispensable in order to enhance the sensitivity of the sensitive material. The above-described afterglow of the fluorescence of a cathode ray tube ranges from 1/10,000,000 to 1/100,000 of a second and with a xenon flash lamp also one of about the same radiation period is used. In the present invention the short time exposure of these two kinds of light sources described above is generically called flash exsposure.
The conventional sensitizer for green light shows markedly lower spectro sensitization under a flash exposure of 1/100,000 of a second or less in comparison with the result of a conventional exposure of 1/1,000 of a second or longer. Specifically there is a fair indication of this trend where, in order to expedite after exposure the treatments such as fixing or stabilization, silver halide is partly or wholly composed of silver chloride, i.e., a silver chloride emulsion, a chlorobromide emulsion or a chloroiodobromide emulsion.
An object of this inventoin is to provide photographic sensitive materials having high sensitivity to green light under flash exposure.
SUMMARY OF THE INVENTION
This invention provides silver halide light sensitive photographic materials comprising a support on which at least one layer having in the binder (such as gelatin and the like) sensitive silver halide grain particles characterized as exhibiting a high surface sensitivity, at least one compound containing a Group VIII metal of the periodic table at the ratio of from 10 - 6 to 10 - 3 mol per 1 mol of silver halide, and at least one optical sensitizer selected from the group consisting of compounds of the general formula: ##SPC3##
wherein R o represents a hydrogen atom or an alkyl group; wherein R 1 and R 2 each represents a hydrogen atom, an alkyl, a substituted alkyl, an allyl, an aryl or an aralkyl group, in which at least one of R 1 and R 2 must be a carboxyalkyl group or a sulfoalkyl group; wherein Y 1 and Y 2 each represents an oxygen atom, a sulfur atom or a >N--R 7 group in which R 7 is an alkyl group; wherein R 3 ; R 4 , R 5 and R 6 each represents a hydrogen atom, a halogen atom, an alkyl, a cyano, an alkoxy or an aryl group, when at least one of R 3 and R 4 is an aryl group, R 5 and R 6 are not an aryl group; wherein X represents an anion, such as a halogen ion or a thiocyanate ion; and wherein m is 1 or 2, in which an intramolecular salt is formed when m is 1, and compounds of the general formula ##SPC4##
wherein R 8 , R 9 and R 10 each represents a hydrogen atom, an alkyl, a substituted alkyl, an allyl, or an aryl group; wherein Y 3 represents an oxygen atom, a sulfur atom or a >N--R 11 group, in which R 11 is a hydrogen atom, an alkyl or an aryl group; wherein L 1 and L 2 each represents the atoms of a methine chain.
DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The accompanying drawing shows the light transmittance of a glass filter V-Y50 used in the examples in evaluating the effectiveness of the light sensitive photographic materials.
DETAILED DESCRIPTION OF THE INVENTION
More particularly, the present invention is described in greater detail as follows.
For supports, glass plates, metal plates, wooden plates, baryta papers, photographic papers, cellulose acetate film bases, polyester film bases can be used.
Suitable binders are water soluble, film forming high molecular weight compounds such as gelatin, polyvinyl alcohol, polyvinyl pyrollidone, sodium alginate, carboxymethyl cellulose. The binders can be used either individually or in combination.
As the light sensitive silver halide, silver chloride, silver bromide, silver chlorobromide, silver iodobromide, silver chloroiodobromide, can be used. The so-called preparation of the sensitive silver halide emulsion, that is, the preparing of the silver halide crystal grains in the binder in a dispersive state, and making them grow into the proper crystal size thus preparing the silver halide emulsion, can be done by conventional techniques.
With respect to the light sensitive silver halide particles employed in the present invention, it must be emphasized that these particles are characterized as exhibiting a high surface sensitivity. Therefore, the silver halide particles of this invention are quite different from particles of the core-shell type, which exhibit low surface sensitivity and high internal sensitivity.
The metals belonging to Group VIII of the periodic tables are iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, platinum. Examples of the compounds containing these metals desirably used in this invention contain a single salt, or a hexagonal complex, tetragonal complex, or square-plane complex of an alkali metal or ammonium such as ferrous sulfate (FeSO 4 .5H 2 O); ferric chloride (FeCl 3 ); potassium hexacyanoferrate (II)(K 4 ]Fe(CN) 6 ] .3H 2 O); potassium hexacyanoferrate (III)(K 3 ]FeCN 6 ]); cobalt (II) chloride (CoCl 2 ); cobalt (II) nitrate (Co[NO 3 ] 2 6 H 2 O); potassium hexacyanocobaltate (III) (K 3 [Co(CN) 6 ]); nickel (II) chloride (NiCl 2 .6H 2 O); nickel (II) nitrate (Ni[NO 3 ] 2 .6H 2 O); ruthenium chloride (RuCl 3 );potassium hexachlororuthenate (IV) (K 2 RuCl6); rhodium (III) chloride (RhCl 3 .4H 2 ); ammonium hexachlorohodate (III) ([NH 4 ] 3 RhCl 6 ): palladium nitrate (Pd[BO 3 ] 2 ); palladium bromide (PdBr 2 ); potassium hexachloropalladate (IV) (K 2 PdCl 6); potassium tetrathiocyanopalladate (II) (K 2 Pd[CNS] 4 ); osmium (II) chloride (OsCl 2 ); iridium (III) chloride (IrCl 3 ); iridium (IV) chloride (IrCl 4 ); iridium (III) bromide (IrBr 3 .4H 2 O); iridium (IV) bromide (IrBr 4 ); potassium hexachloroiridate (III) (K 3 IrCl 6 ;) potassium hexachloroiridate (IV) (K 2 IrCl 6 ); ammonium hexachloroplatinate (IV) ([NH 4 ] 2 PtCl 6 ); potassium hexachloroplatinate (IV) (K 2 PtCl 6 ); ammonium hexabromoplatinate (IV) ([NH 4 ] 2 PtBr 6 ).
These metallic compounds of Group VIII are used either singly or in combinations of two or more compounds together in the silver halide emulsion in a quantity corresponding from 10 - 6 mol to 10 - 3 mol, preferably 10 - 5 to 3 × 10 - 4 , per 1 mol of silver halide. The addition of these compounds in the emulsion can be made suitably at various stages in the preparation, viz., at the formation of silver halide grain particles in the preparation of silver halide emulsion added either in the halide solution or in the dispersive gelatin solution, or at the beginning of the ripening of the emulsion or at intermediate steps. Also, the compound can be added together with other various prior well known stabilizers, antifoggants, antibronzing agents, surface active agents, hardeners, plasticizers, matting agents, development accelerators or brightening agents and the like as desired, prior to the coating of the emulsion.
One of the optical sensitizers in the present invention is the compound having the following general formula: ##SPC5##
wherein R 0 represents a hydrogen atom or an alkyl group having from 2 to 3 carbon atoms, such as a methyl group, an ethyl group and the like; wherein R 1 and R 2 each represents hydrogen or an alkyl group having from 1 to 4 carbon atoms, such as a methyl group, an ethyl group or propyl group and the like, a substituted alkyl group of the type usually used as an N-substituent of a cyanine dye such as a hydroxyalkyl group (e.g., β-hydroxethyl), an acetoxyalkyl group (e.g., β-acetoxyethyl), an alkyl group having a carboxy group such as a carboxy-(alkoxy) n -1 -alkyl group wherein n is 1 or 2 (e.g., carboxymethyl, β-carboxyethyl, γ-carboxypropyl, 2-(2-carboxyethoxy) ethyl), an alkyl group having a sulfo group such as a sulfo -(alkoxy) n -1 -alkyl group wherein n is 1, 2 or 3, a hydroxysulfo-(alkoxy) n -1 -alkyl group wherein n is 1 or 2 or an acyloxysulfoalkyl group (e.g., β-sulfoethyl, γ-sulfopropyl, δ-sulfobutyl, 2-hydroxyl-1-sulfopropyl, 2-(3-sulfopropoxy)ethyl, 2-acetoxy-1-sulfopropyl, 3-methoxy-2-(3-sulfopropoxy)propyl, 2-]2-(3-sulfopropoxy) ethoxy]ethyl, 2-hydroxy-3-(3-sulfopropoxy)propyl, and the like, an aryl group such as phenyl group or an aralkyl group, but at least one of R 1 and R 2 is a carboxyalkyl group or a sulfoalkyl group; wherein Y 1 and Y 2 each are an oxygen atom, a sulfur atom or a >N--R 7 group in which R 7 is an alkyl group having from 1 to 3 carbon atoms, such as a methyl group or an ethyl group and the like; wherein R 3 , R 4 , R 5 and R 6 each represents a hydrogen atom, an alkyl group having from 1 to 3 carbon atoms, such as a methyl group or an ethyl group and the like, a halogen atom (such as fluorine, chlorine, bromine), a cyano group, an alkoxy group (such as a methoxy or an ethoxy group) or an aryl such as a phenyl group but when at least one of R 3 and R 4 is an aryl group then neither R 5 nor R 6 is an aryl group; wherein X is an anion such as a halogen ion, a thiocyanate ion, sulfate ion, sulphamate ion, perchlorate ion, p-toluene sulphonate ion, benzensulphonate ion, ethyl sulphate ion, or methyl sulphate ion, and wherein m represents 1 or 2, in which an intramolecular salt is formed when m =1.
Specific compounds of these optical sensitizers are shown as follows: ##SPC6##
These sensitizers are described, for example, in U.S. Pat. Nos. 2,503,776; 2,912,329 and 3,397,060, French Pat. No. 1,108,788 and Japanese Patent Publication No. 14030/69, and the synthesis of these sensitizers is well known by reference to the patentscited above and also to the relevant technical literature.
Other sensitizers used in the present invention have the following general formula: ##SPC7##
where R 8 , R 9 and R 10 each represents a hydrogen atom; an alkyl group having from 1 to 8 carbon atoms, such as a methyl group, an ethyl group, a propyl group, a butyl group; a substituted alkyl group of the type usually used as an N-substituent of a cyanine dye such as a carboxyalkyl group, (e.g., a carboxymethyl group), a hydroxyalkyl group (e.g., a β-hydroxyethyl group), a sulfoalkyl group (e.g., a β-sulfoethyl group, a γ-sulfopropyl group); an allyl group; or an aryl group such as a phenyl group, a substituted phenyl group (for example, substituted with a halogen atom e.g., a chlorine atom, an alkyl group and the like); wherein Y 3 is an oxygen atom, a sulfur atom or a >N--R 11 group, in which R 11 is a hydrogen atom, an alkyl group having from 1 to 8 carbon atoms, or an aryl group (e.g., a phenyl group); wherein L 1 and L 2 in each a methine chain (e.g., =CH--, =C(alkyl)--; =C(aryl)--; wherein examples of the alkyl group and the aryl group are a methyl group and a phenyl group, respectively).
Specific compounds of these sensitizers are as follows: ##SPC8##
These sensitizers are described, for example, in the British Pat. No. 801,275 and the synthesis of these sensitizers is well known by reference to the patent cited above and also to the relevant technical literature.
These optical sensitizers are applied, either singly or in combination of two or more, at a ratio of from 10 - 6 to 10 - 3 mol, preferably 10 - 15 to 3 × 10 - 4 mol, per 1 mol of silver halide in the silver halide emulsion. This addition of the optical sensitizer to the emulsion is the same as with the metal compounds above described. The addition into the emulsion can be made either simultaneously with the metal compound, or separately. The sequence of the addition is immaterial.
Thus, it can be seen that the silver halide light-sensitive photographic material can be made essentially in the same manner as usual except that the above metal compound and optical sensitizer are added and the sensitive material thus prepared can, after flash exposure, be developed and fixed in a conventional manner. Also, the material can be treated in a manner known generally as the diffusion transfer process. Or, by adding beforehand an ample quantity of the developing agent in the light-sensitive layer, the development can be treated by the generally known activator development process (a process by which the light-sensitive material containing a developing agent is developed in a solution which does not contain a developing agent and in which only alkaline material is dissolved).
It has been observed that with light-sensitive materials containing the above-described metal compounds but not containing the optical sensitizers, the sensitivity to the green light is not obtained, although, in some cases, their sensitivity to blue light improves. On the other hand, it is recognized that in the case of the sensitive material not containing the metal compounds but containing only the optical sensitizers, the green light sensitivity is not very high. However, by using these two types of materials simultaneously the green light sensitivity in the flash exposure can be markedly improved.
Specifically, with a silver chloride emulsion, a silver chlorobromide emulsion, or a silver chlorobromoiodide emulsion, if the above sensitizer is used alone, a considerable lowering of the efficiency of spectral sensitization in the flash exposure is experienced. For such emulsions the present invention is particularly useful.
It has long been known that the metal compounds described above show various noticeable effects, and as is shown in U.S. Pat. No. 2,448,060, when hexahalogenoruthenium (III) acid salts, hexahalogenorhodium (IV) acid salts, hexahalogeno osmium (IV) acid salts, hexahalogenoiridium (IV) acid salts, or hexahalogenoplatinum (IV) acid salts are added to a silver halide emulsion at the time of ripening, the sensitivity of this emulsion increases. And further, as is disclosed in U.S. Pat. No. 2,566,745, when these compounds are added additionally to the silver halide emulsion the stability of the sensitive material under high temperatures and humidity improves, and further, as is disclosed in U.S. Pat. No. 2,517,541, potassium hexacyanocobaltate (III) and in FIAT Report No. 360 rhodium trichloride, when this compound is added to a silver halide emulsion the contrast of the image obtained from this emulsion increases.
We have found that the iron compounds make the contrast of the emulsion higher.
The compounds of Group VIII elements in the periodic table are added solely for the objects of this invention, but they can also be used to obtain various photographic effects as described above at the same time. Also, as is shown in British Pat. No. 570,393, one can apply the method of increasing the sensitivity of the emulsion by adding the metal compounds at the time of ripening. In other words, when used as a sensitizer or as a stabilizer or as an additive for increasing contrast, the effect of sensitization to green light is displayed if the above dyes are used together. The efficiency which the usual techniques aim at is not hindered.
The present invention will be illustrated in greater detail by the following examples.
EXAMPLE 1
An ordinary acid process silver chlorobromide emulsion was prepared (containing 30 mol % AgBr) not containing the compounds containing metals of Group VIII of the periodic table (hereinafter simply called metal compounds) and by the same method an emulsion was prepared, and at the time of forming the silver halide grains, ammonium hexachlororhodate (III) was added in a quantity equivalent to 7 × 10 - 6 mol per silver halide 1 mol, and at the after-ripening step, potassium hexachloroplatinate (IV) was added in a quantity corresponding 2 × 10 - 5 mol per silver halide 1 mol and the thus prepared emulsion was similar in sensitivity to the conventional emulsion. Each of these 2 emulsions was divided into two parts. One part was not dye-sensitized. To the other was added Dye I in a quantity of 4 × 10 - 3 mol per 1 mol of silver halide in the emulsion. Next, formaldehyde was added to each of these in a quantity of 2.5 per 100 g of gelatin of the emulsion, and then each was applied to a photographic baryta paper.
Using an EG & G Sensitometer Mark VII and through a colored glass filter V-Y50 (made by Tokyo Shibaura Electric Co., Ltd.) and an optical wedge, the above described samples were each given exposures of 1/100 and of 1/1,000,000 of a second. As is shown in the drawing, the colored glass filter V-Y50 (made by Tokyo Shibaura Electric Co., Ltd.) absorbs the light corresponding to the sensitive spectral region of the unsensitized silver halide and transmits only the light corresponding to the optically sensitized region of greater than about 500 nm. The exposed samples were developed at 20°C for 2 seconds in the following developer: N-Methyl-para-aminophenol 2 g Sodium Sulfite, Anhydrous 30 g Hydroquinone 7 g Sodium Carbonate (Monohydrate) 53 g Potassium Bromide 1.5 g Water up to 1 liter
After fixing, rinsing and drying, the reflective density of the images were measured.
The reciprocal of the light quantity giving a density of 0.5 was set as the sensitivity value, but, since the absolute light quantity through the filter was not measured, the sensitivity was only relative, but in the following table the sensitivities of the same exposure time could be in the corresponding state. The results obtained are shown in the table below.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye I Only 4.9 0.9 Group VIII Metal + Dye I 4.6 3.2 ______________________________________
It was observed that by using the rhodate compound, the platinate compound and Dye (I) the green light sensitivity to flash exposure was increased.
EXAMPLE 2
A silver chlorobromide emulsion (containing 50 mol percent AgBr) was prepared in a neutral medium by a well known process and which does not contain the compounds of a Group VIII metal of the periodic table (hereinafter simply called metal compounds), and one was also prepared by adding hexachlororhodate (III) in a quantity of 3 × 10 - 6 mol per 1 mol of silver halide in the above emulsion at the time of the formation of the silver halide grains, then further after ripening potassium chloroplatinate was added in a quantity of 2 × 10 - 5 mol per silver halide 1 mol. The thus prepared emulsion had about the sensitive as the above-described emulsion. These two emulsions were each divided in two parts. One was left intact.
To the other part was added the Dye X in a quantity of 6 × 10 - 3 mol per 1 mol of silver halide in the emulsion. Next, formaldehyde was added to each of these in the quantity of 2.5 g per 100 g of gelatin of the emulsion, and the emulsion was applied to a photographic baryta paper.
The green light sensitivity was measured for the sample thus obtained in the manner as described in Example 1 and the following results were obtained.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye X Only 12.0 2.7 Group VIII Metal + Dye X 10.5 7.2 ______________________________________
It was observed that by using simultaneously the rhodate salt, the platinate salt and Dye X, the green light sensitivity to the flash exposure was increased.
EXAMPLE 3
A silver chlorobromide emulsion (AgCl 50 mol percent, AgBr 50 mol percent) which does not contain the metal compounds of this invention was prepared in a neutral medium in a conventional manner.
Next, by the same method, at the formation of the silver halide grains, 3 × 10 - 6 mol per 1 mol of silver halide of ammonium hexachlororhodate was added to the emulsion, and then after ripening, platinum (IV) chloride in the quantity of 2 × 10 - 5 mol per silver halide 1 mol was added to prepare an emulsion having a sensitivity similar to that of the emulsion without the metal compounds. To each of these emulsions, as in Example 1, Dye IV at a level of 2 × 10 - 3 mol per 1 mol of silver halide was further added. In addition, 2.5 g of formaldehyde was added per 100 g of gelatin, and the emulsion was applied to a photographic baryta paper. The optical sensitization of the sample obtained was measured in the same manner as described in Example 1. The results obtained are shown in the following table.
______________________________________ 1/100 1/1,000,000 Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye IV Only 12.7 2.9 Group VIII Metal + Dye IV 10.8 7.5 ______________________________________
In this case the effect of using the rhodate compound, the platinate salt and Dye IV together was observed.
EXAMPLE 4
A silver chlorobromide emulsion (AgBr 70 mol percent, AgCl 30 mol percent) which does not contain the metal compounds of this invention was prepared in an ammonium alkali medium in a conventional manner. Next, in the same manner potassium hexacyanoferrate (III) was added in a quantity of 1 × 10 - 5 mol per 1 mol of silver halide of the emulsion at the formation of silver halide grains. To these two emulsions Dye III was added in quantity of 2 × 10 - 5 mol per 1 mol of the silver halide.
Further, formaldehyde in a quantity of 2.5 g per 100 g of gelatin was added and the emulsion was applied to a photographic baryta paper. The sensitivity to green light of the samples thus obtained was measured in the same manner as described in Example 1. The results obtained are shown in the table below.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Alone 0 0 Dye III Alone 63 13 Group VIII Metal + Dye III 68 47 ______________________________________
In this case the combined effect of a Group VIII metal compound and Dye III was observed.
EXAMPLE 5
A silver chlorobromoiodide emulsion (AgBr 70 mol percent, AgCl 29 mol percent, Agl 1 mol percent) which does not contain the metal compounds of this invention was prepared in an ammonium alkali medium using a conventional method. Next, using the same procedure, 4 × 10 - 6 mol per 1 mol of silver halide of potassium hexacyanoferrate (III), 6 × 10 - 8 mol per 1 mol of silver halide of potassium hexachloroiridate (IV), 3× 10 - 7 mol per 1 mol of silver halide of ammonium hexachlororhodate (III) were added at the time of formation of the silver halide grains, and again at the after-ripening 3 × 10 - 6 mol per 1 mol of silver halide of chloroauric acid was added, and prepared an emulsion having a sensitivity similar to that of the ordinary sensitivity.
To this emulsion as well as to the emulsion described above, Dye III in a quantity of 6 × 10 - 3 mol per silver halide 1 mol was added. Further, formaldehyde 2.5 g per 100 g of gelatin was added and the emulsion was applied to a photographic baryta paper. The green light sensitivity of this sample was then measured in the same manner as in Example 1. The results obtained are shown in the table below.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye III Only 177 43 Group VIII Metal + Dye III 111 98 ______________________________________
Also, in this case the effect of the joint application of the Group VIII metal salt and Dye III was observed.
EXAMPLE 6
To the emulsion as used in Example 3 Dye VI was added corresponding to a quantity of 8 × 10 - 3 mol per silver halide 1 mol, and this sample was tested in the same manner as described in Example 1. The results obtained are shown in the table below.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye VI Only 336 77 Group VIII Metal + Dye VI 237 246 ______________________________________
In this case also, the effect of the combined treatment of Group VIII metal salt and Dye VI was observed.
EXAMPLE 7
A silver chlorobromide emulsion (AgCl 50 mol percent, AgBr 50 mol percent) which does not contain the metal compounds of this invention was prepared in an ammonium alkali medium in a conventional manner. Next, using the same procedure, at the formation of the silver halide grains, 1 × 10 - 5 mol per 1 mol of silver halide of potassium hexacyanoferrate (III) was added and the emulsion having a sensitivity similar to that of the emulsion not containing metal compounds was obtained. To each of these emulsions, as described in Example 1, Dye VIII was added in a quantity of 4 × 10 - 3 mol per 1 mol of silver halide. Further, formaldehyde in a quantity of 2.5 g per 100 g of gelatin was added, and the emulsion was applied to a photographic baryta paper. The sensitivity to green light of the thus obtained samples was measured using the same method as used in Example 1 and the following results were obtained.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye VIII Only 48 11 Group VIII Metal + Dye VIII 49 35 ______________________________________
In this case also, the combined effect of the ferrate and the Dye VIII was observed.
EXAMPLE 8
A chloroiodobromide silver halide emulsion (AgBr 70 mol percent, AgCl 29 mol percent, Agl 1 mol percent) was prepared not containing metallic compounds of the present invention, using the conventional ammonium method. To an emulsion of the same composition were added at the formation of silver halide grain particles, 4 × 10 - 6 mol potassium hexacyanoferrate (III) 6 × 10 - 8 mol potassium hexachloroirridate (IV), 3 × 10 - 7 ammonium hexachlororhodate (III) per 1 mol silver halide in the emulsion, and then, at the after-ripening, 3 × 10 - 6 per 1 mol of silver halide of chloroauric acid was added. A sensitivity similar to that of the above-described ordinary emulsion was obtained.
To these emulsions was added Dye VII in a quantity corresponding to 2 × 10 - 3 mol per silver halide 1 mol. Again, to these emulsions was added formaldehyde in a quantity of 2.5 g per 100 g of gelatin to prepare a photographic emulsion which was applied to a photographic baryta paper. The green light sensitivity of the sample was measured in the same manner as in Example 1. The results obtained are shown in the table below.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye VII Only 140 27 Group VIII Metal + Dye VII 100 74 ______________________________________
In this instance also the effect of the combined use of the Group VIII metal salt and Dye VII was observed.
EXAMPLE 9
Dye XVI was added to an emulsion which was the same as used in Example 3 in a quantity of 2 × 10 - 3 mol per 1 mol of silver halide. The emulsion was then treated the same as in Example 3 and tested in the same way as Example 1.
______________________________________ 1/100th 1/1,000,000th Second Second Exposure Exposure ______________________________________ Control Emulsion 0 0 Group VIII Metal Only 0 0 Dye XVI Only 139 30 Group VIII Metal + Dye XVI 89 79 ______________________________________
In this case also the effect of the combined use of the Group VIII metal salt and Dye XVI was observed.
In all the foregoing Examples, the silver halide particles employed were those which exhibited a homogeneous structure and further, exhibited a high surface sensitivity.
While the present invention has been adequately described in the foregoing specification and Examples included therein, it is readily apparent that various changes and modifications can be made to the same without departing from the spirit and scope thereof.