JPH07301875A - Silver halide photographic sensitive material - Google Patents

Abstract

PURPOSE:To obtain the photosensitive material superior in time lapse stability and wide in latitude by specifying each of the average grain size of silver halide grains in a coarse grain emulsion and a ratio of gold amount used for the coarse grain emulsion to that used for a fine grain emulsion. CONSTITUTION:The photosensitive material having on a support at least one silver halide emulsion layer containing a mixture of at least 2 kinds of silver halide emulsions of maximum size emulsion (coarse grain emulsion) and a minimum size emulsion (fine size emulsion) having different average grain size from each other and a grain size ratio of >=(1.5:1) of the average grain size of the coarse grain emulsion to that of the fine grain emulsion, and a ratio of the gold amount used for the fine grain emulsion to that for the coarse grain emulsion of <(1.5:1). The silver halide to be used for the emulsion is selected from silver chloride, silver bromide, silver iodide, silver chlorobromide, silver iodochloride, silver iodobromide, and silver iodochlorobromide.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a silver halide photographic light-sensitive material.

[0002]

2. Description of the Related Art Generally, the exposure latitude of a silver halide photographic light-sensitive material is broadened by mixing silver halide emulsions having different sensitivities or by providing such silver halide emulsions as separate light-sensitive layers. What you can do is well known. In this case, the individual silver halide emulsions mixed can be varied within wide limits depending on the photographic characteristics of the emulsion and the desired effect. It is also well known that a silver halide emulsion having high sensitivity and low sensitivity can be obtained by selecting the grain size of silver halide grains. However, in a mixed emulsion prepared with emulsions having different grain sizes,
It is often the case that the exposure latitude does not spread as expected. For example, in Japanese Patent Publication No. 51-28027,
Gradation control of the silver halide emulsion is performed by making full use of such characteristics. Also, with a high-sensitivity emulsion,
Although a method of obtaining a wide latitude of a silver halide emulsion by coating the low-sensitivity emulsion in separate layers is also used, but it is not preferable because the production equipment becomes complicated and the coating cost increases. On the other hand, JP-A-59-45974 succeeded in obtaining a wide exposure latitude by defining the amount of sensitizing dye used in the emulsion to be mixed. However, in such a method, it is difficult to maintain a wide latitude because the performance change with time due to the stagnation time from the emulsion mixing to the coating is significant,
In practice, it was difficult to manufacture for use as the final product.

[0003]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a photographic light-sensitive material having excellent stability over time after mixing of silver halide emulsions having different sensitivities and, as a result, having a wide latitude. To do.

[0004]

The above-mentioned objects have been achieved by the following means. (1) A photographic light-sensitive material having at least one silver halide emulsion layer on a support, in which at least one of the silver halide emulsion layers has a different average grain size, a maximum size emulsion (coarse grain emulsion) And a mixture of at least two silver halide emulsions of a minimum size emulsion (fine grain emulsion), and the average grain size of the silver halide grains in the coarse grain emulsion is the average of the silver halide grains in the fine grain emulsion. 1.5 times the grain size or more and the amount of gold used for the fine grain emulsion /
The silver halide photographic light-sensitive material characterized in that the ratio of the amount of gold used in the coarse grain emulsion is less than 1.5, and both the coarse grain emulsion and the fine grain emulsion contain tabular grains having an aspect ratio of 1.5 or more. The silver halide photographic light-sensitive material described in (1) above is the photographic light-sensitive material according to the present invention.

The silver halide photographic light-sensitive material of the present invention will be described in more detail below. The silver halide emulsion used in the present invention may be appropriately selected depending on the photographic characteristics or effects required for the photographic light-sensitive material. Regarding silver halide photographic emulsions, the description of Research Disclosure No. 17643 and No. 193227 can be referred to.

The silver halide used in the silver halide emulsion used in the present invention is, for example, silver chloride, silver bromide, silver iodide, silver chlorobromide, silver chloroiodide, silver bromoiodide or chloroiodide. It is appropriately selected from silver bromide and the like. Further, as the shape, tabular grains, regular grains, agglomerated grains and the like can be selected so as to meet desired photographic performance.

Further, the average grain size and grain size distribution of the silver halide grains contained in the silver halide emulsion are selected according to the characteristics desired for the photographic light-sensitive material, but in order to obtain a wide latitude and soft photographic properties. It is necessary that the ratio of the average particle diameters is 1.5 or more. The average grain size of silver halide grains can be measured by, for example, "The Theory of
Photographic Process "by James, 4th
Edition, page 100).

In the present invention, at least two silver halide emulsions having different average grain sizes to be mixed are gold-sensitized with gold prior to mixing. Even if gold sensitization is performed after mixing, it is difficult to optimally gold sensitize each grain because the particle diameters are different, and the maximum performance cannot be obtained. Therefore, only emulsions having inferior photographic performance such as sensitivity and graininess can be obtained as compared with emulsions obtained by sensitizing with gold. Therefore, after gold sensitizing each silver halide emulsion,
It is necessary to mix each emulsion. However, a change in performance over time due to a stagnation time before mixing after mixing has occurred as a major problem in manufacturing.

As a result of intensive studies, the present inventors have found that the change in performance is caused by the difference in the amount of gold used per 1 mol of silver in each emulsion. Ie silver 1
It was discovered that a large difference in the amount of gold added per mole causes migration of gold between each emulsion after mixing, resulting in a change in performance. Therefore, to prevent the change over time after mixing emulsions, 1 mol of silver used for each emulsion should be used.
The ratio of the amount of gold used per l, that is, (amount of gold used for fine grain emulsion) / (amount of gold used for coarse grain emulsion) is 1.
It is preferably less than 5, more preferably 1.5 to 1.
It has been found that a value of 0, 1.3 to 1.0 is important.

Usually, the amount of gold used for gold sensitization is proportional to the total surface area of grains. Therefore, the larger the total surface area of the fine particles, the larger the amount of gold used, and the larger the particles, the smaller the amount of gold used. For example, the particle size of fine particles is 1 of coarse particles.
At / 2, the amount of gold sensitizer required is doubled.
In order to satisfy the above-mentioned requirements, the emulsion used in the present invention uses a larger amount of gold than that usually used for grains having a large average particle diameter, Perform gold sensitization with less gold than is used. Even if the amount of gold is changed, the best performance can be given to the emulsion by adjusting the gold sensitization time within a certain range. Cannot be given.

Further, tabular grains having a large specific surface area and a high aspect ratio (equivalent circle diameter / thickness of particles) are used for the particles having a large average particle size, and small specific surface areas are used for the particles having a small average particle size. It is also a preferred embodiment of the present invention to reduce the ratio of (amount of gold used for fine grain emulsion) / (amount of gold used for coarse grain emulsion) by using regular grains or tabular grains having a low aspect ratio. The silver halide grain according to the present invention may be a normal crystal, a twin crystal such as a tabular crystal, or a mixture thereof.

The tabular silver halide emulsion used in the present invention will be described in detail. The tabular grains of the present invention (hereinafter also referred to as "tabular grains") are grains having an aspect ratio of 2 to 100. The aspect ratio is a value obtained by dividing the circle-equivalent diameter of the projected area of a grain by the grain thickness, and can be determined from an electron micrograph of tabular grains. 0.1 as equivalent circle diameter
The range is preferably from 10 to 10 microns, more preferably from 0.3 to 5 microns, and particularly from 0.6 to 3 microns. The particle thickness is preferably 0.6 micron or less, more preferably 0.4 micron, and particularly preferably 0.25 micron or less. More preferable aspect ratio is 3 to 3
0, especially preferred is the range of 4-15. The tabular grains of the present invention account for 50% or more, preferably 75% or more, and particularly preferably 90% of the projected area of all the silver halide grains in the emulsion. Aspect ratio divided by grain thickness (flatness,
Tabularity) can be easily determined. The preferred flatness is 10 or more, more preferably 25 or more, especially 50.
The above is preferable. It is preferable to make uniform the shapes such as the equivalent circle diameter, particle thickness, particle volume or aspect ratio. The uniformity is represented by a value (variation coefficient) obtained by dividing the standard deviation of characteristic values by the average value. Characteristic value of at least one of circle equivalent diameter, particle thickness, or aspect ratio is coefficient of variation 2
When it is 0% or less, more preferably 15% or less, and particularly 10% or less, it is called a monodisperse emulsion and it is a preferred embodiment for the emulsion of the present invention.

The crystal plane of the silver halide grain is (100)
Although there are various planes such as (110), (111) and (331), the main plane of the tabular grain of the present invention is composed of (111) or (100) planes. The (111) main plane tabular grains contain twin planes. In the case of the tabular grains of the present invention, grains having two or more parallel twin planes are preferable, and parallel double twin grains are a preferable embodiment. A value obtained by dividing the grain thickness by the distance between twin planes can be selected according to the purpose. In the case of the present invention, 5 or more of US Pat. No. 4,853,322 is preferable, 10 or more, particularly 15 or more is preferable. As the shape of the (111) main plane tabular grain, a triangle, a hexagon and a circle can be selected according to the purpose.
The regular hexagonal monodisperse plate of U.S. Pat. No. 4,797,354 and the circular monodisperse plate of U.S. Pat. No. 4,977,074 are preferred embodiments of the present invention, and the production method can be according to each U.S. patent. It is preferable that the side faces or edges of the (111) main plane tabular grain include a face other than the (111) face, a (100) face, a (110) face or a (331) face. A grain having 10% or more of the side area having a crystal plane other than the (111) plane and a grain having 50% or more of the side area are preferable as the tabular grain of the present invention. A square or a rectangle can be selected as the shape of the (100) main plane tabular grain. It is also possible to make at least one corner rounded according to the purpose. The manufacturing method can follow US Pat. No. 4,386,156 and European Patent No. 0534395A1.

As the halogen composition of the normal crystal or tabular grains of the present invention, silver chloride, silver bromide and silver iodide and a mixed crystal of each combination can be selected. The preferred grains for the present invention are first 90% or more of silver bromide, further 99% or more of silver bromide, secondly 30% or less of silver iodide, further 1%.
Silver iodobromide grains containing ˜15% silver iodide, especially 2% to 10% silver iodide, third less than 50 mol% silver chloride, and further 1
% To 15% silver chloride, in particular 2% to 5% silver chloride, silver chlorobromide grains, and fourth, silver chloroiodobromide grains containing 10% or less silver chloride and 10% or less silver iodide. Fifthly, 60% or more is silver chloride, 90% or more is silver chloride, and particularly 99% or more is silver chloride grains. These compositions can be selected in consideration of the light absorptivity of silver halide, the adjustment of the adsorption power of the sensitizing dye, the progress of development and the solubility of silver halide. Grains having partial structures having different halogen compositions within one grain are preferred tabular grains in the present invention. A preferred structure can be selected from a double-structured particle composed of an inner core and an outer shell, a multi-structured particle composed of an inner core and one or more inner shells and an outermost shell, and particles epitaxially grown on a specific portion of a base tabular grain. Firstly, a high iodine phase of 5 mol% to solid solubility limit, further 10 mol% or more, especially 20% or more of silver iodide is arranged in the inner core of the grain, and secondly, the inner shell portion of the multi-structure grain is prepared. When growing, silver iodide or silver halide containing 10 mol% or more of silver iodide is grown. Thirdly, silver halide containing 10 mol% or less of silver iodide in the outer shell or outermost shell, odor. Choose the composition of silver halide, silver chlorobromide and silver chloride, and fourth, the more insoluble silver halide (for silver chloride, silver chlorobromide, silver bromide, iodoodor) Deposition by adding silver iodide, silver chloroiodobromide or silver iodide, or silver bromide to silver iodobromide or silver iodide) water-soluble halide, silver halide fine particles or halogen ion-releasing compound This is a particularly preferred structure for the tabular grains of the present invention. U.S. Pat. No. 4,668,614 for the first and U.S. Pat. No. 46 for the second.
14711, 4713318 and 4665012
Nos. 3 and 4, U.S. Pat.
Nos. 77075 and 5059517, and U.S. Pat. Nos. 4,783,398 and 5,206,134 are preferred modes for the fourth, and the X-ray diffraction method is used for the grain structure of each.
It can be analyzed by analytical electron microscopy, ESCA or ISS. Increasing the uniformity of the halogen composition of the individual grains or providing a specific correlation between the halogen composition of the individual grains and the grain size is preferred for the present invention. Regarding the uniformity, the variation coefficient of the silver iodide content between grains is preferably 20% or less, more preferably 10% or less.
In some cases, it is also meaningful to define the uniformity of silver bromide content or silver chloride content between grains. A preferred example is the emulsion described in US Pat. No. 4,835,095. The larger size grains have a higher silver iodide content or the higher silver bromide content than the smaller size grains, or have the opposite correlation, depending on the purpose. It is preferable for preparing the planar particles of the present invention that the mixed crystal particles or the mixed crystal portion of the structured particles be made microscopically uniform. The apparatus and particle formation method described in US Pat. Nos. 4,879,208 and 5,035,991 are preferred embodiments.

It is highly preferred that the normal crystal or tabular grains of the present invention contain structural defects. It can be selectively used according to the purpose from twin planes as plane defects, dislocations as line defects, and Frenkel defects and impurities as point defects. Dislocations of tabular grains can be observed using a transmission electron microscope with a high acceleration voltage. It has been shown in U.S. Pat. No. 4,806,461 that the inclusion of dislocations is important for the tabular grain pressure and photographic properties. Particles having 10 or more dislocations per particle, further 100
Particles containing one or more dislocations are preferred. The site where the dislocations are introduced can be limited to the center of the grain, along the outer periphery of the grain or at the apex of the grain, and it can be used properly according to the purpose. In the case of the tabular grains of the present invention, it is preferable to introduce them only at the outer periphery or apex of the grains. It is particularly preferable that dislocations are uniformly and densely introduced into all grains. The action of impurities affecting the process of electrons and holes or the process of interstitial silver ions and silver ion vacancies is important for the tabular grains of the present invention. Group 8 ions (Ru, Rh, P as cation impurities)
d, Os, Ir, Pt) or Mn, Fe, Cu, Z
Salts of n, Cd, Tl, Au, Hg, etc. may be mentioned. Also, a complex salt of Cl, CN, NO or the like can be used. Examples of anion impurities include S, Se, Te or SCN, SeCN. The doping amount can be selected according to the purpose from the range of 10 ⁻⁸ to 10 ⁻³ mol / mol Ag. The embedding of small clusters of metallic silver (reduction sensitizing nuclei) as another dopant is particularly preferred for the tabular grains of the invention. U.S. Pat. No. 5,968,863, wherein a reduction sensitizer such as thiourea dioxide, SnCl ₂ , borane compound or ascorbic acid is added during grain growth or physical ripening and a thiosulfonic acid compound is used in combination.
The sensitizing method of No. 61614 is a preferred embodiment.

The tabular grains of the present invention are (US) Pat. No. 4,797,354 in the case of (111) plane grains mainly containing AgBr.
Nos. 4,475,456 and 5,087,555, in the case of (111) plane grains mainly composed of AgCl, U.S. Pat. Nos. 4,400,473, 4,783,398 and 4,713.
323 and in the case of (100) face grains US Pat. No. 4,386,156 and European patent 0534.
It can be prepared according to 395A1. Nucleation step in which temperature, gelatin seed and amount, pBr and pI, addition rate of silver and halogen solution are strictly controlled, excluding particles other than the intended particles and growing only the intended particles to obtain seed particles having good monodispersity. The growth is controlled by controlling the ripening process and the ratio of the growth rate in the side surface to the main plane direction with respect to the seed tabular grain, and changing the amount of silver halide supplied per unit time with time to keep it within the range of 30 to 100% of the critical growth rate. Obtaining tabular grains having good monodispersity by employing steps is particularly preferable as the method for preparing the grains of the present invention. In the manufacturing process,
It is sometimes preferred to utilize their solvent action by adding with ammonia, thioethers, thioureas, thiocyanate salts, thiazoline thiones or by generating in the reaction vessel. A so-called seed crystal method in which only seed grains are separately prepared is useful for the purpose of improving reproducibility of emulsion preparation.

The normal crystal grains or tabular grains of the present invention are chemically formed on the surface of the grain in the case of the surface latent image type, in the shallow inside of the grain in the case of the shallow internal latent image type, and inside the grain in the case of the internal latent image type. It is preferable that sensitizing nuclei are arranged. In the case of chalcogen chemical sensitization, small clusters of silver sulfide, silver selenide, silver telluride and their mixed clusters become the chemical sensitization nuclei, and in the case of gold chalcogen chemical sensitization, the mixed cluster of chalcogen silver and chalcogen gold is chemically sensitized. It is considered to be a sensitizing nucleus. Sulfur sensitization by reactive sulfur compounds (thiosulfates, thioureas, mercapto compounds, rhodanins), unstable selenium (selenourea, phosphine selenide, etc.) or stable selenium (selenocyanate) compounds Sensitivity, unstable tellurium (phosphine telluride, etc.) compound tellurium sensitization, SCN or S
Addition of eCN compound, addition of Au sensitizer and its complex forming compound, addition of complex salt of Group 8 metal such as Pt, Ir, Pd, reducing substance (SnCl ₂ , hydrazine derivative, thiourea dioxide, borane compound, ascorbine) Acid) or the addition of a thiosulfonic acid compound is preferably used in order to chemically sensitize the tabular emulsion of the present invention.

The normal crystal or tabular silver halide grains of the present invention are preferably spectrally sensitized with methine dyes. Dyes used include cyanine dyes, merocyanine dyes,
It includes complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes and hemioxonol dyes. Particularly useful dyes are those belonging to the cyanine dyes, merocyanine dyes, and complex merocyanine dyes. The photographic emulsion used in the present invention may contain various compounds for the purpose of preventing fog during the production process of the light-sensitive material, during storage or photographic processing, and stabilizing photographic performance. That is, azoles such as benzothiazolium salts, nitroimidazoles, triazoles, benzotriazoles, benzimidazoles (particularly nitro- or halogen-substituted compounds); heterocyclic mercapto compounds such as mercaptothiazoles, mercaptobenzothiazole Kind,
Mercaptobenzimidazoles, mercaptothiadiazoles, mercaptotetrazoles (particularly 1-phenyl-5-mercaptotetrazole), mercaptopyrimidines; the above heterocyclic mercapto compounds having a water-soluble group such as a carboxyl group or a sulfone group; Thioketo compounds such as dolinthion; azaindenes, such as triazaindenes, tetraazaindenes (especially 4-hydroxy-substituted (1,3,3a, 7) tetraazaindenes); benzenethiosulfonic acids; benzenesulfinic acid Many compounds known as antifoggants or stabilizers such as; can be added.

The technique of US Pat. No. 4,968,595 which limits the starting point of development to the corners or edges of the tabular grains is important for the tabular grains of the present invention. It is preferable to add the above-mentioned sensitizing dye or antifoggant before or during the chemical sensitization so that an effective amount as a modifier for the chemical sensitization is allowed to act. The tabular emulsion of the present invention is preferably oriented parallel to the support in the photosensitive layer from the viewpoint of optical scattering. Further, in order to particularly improve the sharpness, it is preferable to accurately control the thickness of the particles according to the wavelength of incident light. For blue light of 400 to 500 nm, 0.
08-0.10 microns, 0.11-0.13 microns for green light of 500-600 nm, 600-700
For red light of nm, it is preferred to place particles with a thickness of 0.14 to 0.17 microns.

The silver halide emulsion of the present invention can be used in black and white and color photographic light-sensitive materials. Regarding technology such as layer arrangement that can be used for color photographic light-sensitive materials, silver halide emulsions, dye-forming couplers, functional couplers such as DIR couplers, various additives, and development processing,
It is described in European Patent No. 0565096A1 (published October 13, 1993) and the patents cited therein. The items and corresponding description points are listed below. 1. Layer structure: p. 61, line 23-35, p. 61, line 41-p. 62, line 14. intermediate layer: p. 61, p. 36-40, 3. multilayer effect imparting layer: p. 62, p. 15-18, 4. halogen Silver halide halogen composition: page 62, lines 21-25, 5. Silver halide grain crystal habit: page 62, lines 26-30, 6. Silver halide grain size: page 62, lines 31-34, 7. Emulsion production method: 62 P. 35-40 lines, 8. silver halide grain size: 62 p. 41-42 lines, 9. tabular grains: p. 62 p. 43-46 lines, 10. grain internal structure: p. 62-47-53 lines, 11. emulsions Latent image formation type: page 62, line 54-page 63, line 5, 12. Physical and chemical ripening of emulsion: page 63, line 6-9, 13. Mixed use of emulsion: page 63, line 10-13, cover 12. Emulsion: page 63, lines 14-31, 15. Non-photosensitive emulsion: page 63, lines 32-43, 16. Coating silver amount: page 63, lines 49-50, 17. Photographic additive: Research Disclosure (RD) 17
643, 18716 and 307105 (page 64), 18. Formaldehyde scavenger: page 64, lines 54-57, 19. Mercapto-type antifoggant: page 65, lines 1-2, 20. Release agents such as fogging agents : P. 65, line 3-7, 21. Dye: P. 65, line 7-10, 22. General color coupler: P. 65, line 11-13, 23. Yellow, magenta and cyan coupler: P. 65, 14-
25 lines, 24. Polymer couplers: page 65, lines 26-28, 25. Diffusible dye forming couplers: page 65, lines 29-31, 26. Colored couplers: page 65, lines 32-38, 27. Functional couplers in general: 65 Pages 39-44, 28. Bleach accelerator releasing coupler: Page 65, lines 45-48, 29. Development accelerator releasing coupler: Page 65, lines 49-53, 30. Other DIR couplers: Page 65, lines 54-66. 4 lines, 31. Coupler dispersion method: page 66, lines 5-28, 32. Preservatives / antifungal agents: page 66, lines 29-33, 33. Types of photosensitive materials: page 66, lines 34-36, 34. Photosensitive layer Film thickness and swelling speed: page 66 line 40-67 page line 1, 35. back layer: page 67 line 3-8, 36. general development process: page 67 line 9-11, 37. developer and developer: 67 Pp. 12-30, 38. developer additive: p. 67, p. 31-44, 39. reversal treatment: p. 67, p. 45-56, 40. treatment liquid aperture ratio: p. 67, p. 57-p. 12, p. 12, 41. Development time: 68 pages, 13-15 lines, 42. Bleach fixing, bleaching, fixing: 68 pages, 16 lines-69 pages, 31 lines, 43. Automatic developing machine: 6 Page 9, lines 32-40, 44. Rinsing, rinsing, stabilization: Page 69 line 41-Page 70 line 18, 45. Replenishment and reuse of processing solution: Page 70 lines 19-23, 46. Built-in developer sensitizer: Page 70, lines 24-33, 47. Development processing temperature: Page 70, lines 34-38, 48. Use for film with lenses: Page 70, lines 39-41

The photographic light-sensitive material using the emulsion of the present invention is not particularly limited and can be used as a general black-and-white light-sensitive material. For example, a system for irradiating an X-ray or the like on an object such as a human body such as an X-ray film for direct shooting, an X-ray film for indirect shooting, a CRT film, etc., and converting the X-rays passing through the object into visible light for exposure. Used for. Specifically, medical or industrial X-ray photographic materials, X-ray dupe photographic materials,
Examples thereof include photographic materials for medical CRT images.
The present invention will be described in more detail below, but the present invention is not limited by the following.

[0022]

【Example】

 Example 1 Emulsion 1-A (preparation of 0.23 μ emulsion) (1) Grain formation

An aqueous solution of AgNO ₃ (10 g) was added to 1.6 liter of an aqueous solution containing 4.3 g of KBr and 7.5 g of gelatin having an average molecular weight (M) of 20,000 by a double jet method while stirring.
While stirring 20.48 g of AgNO ₃ in 0 ml and an aqueous KBr solution (containing 14.3 g of KBr and 2.7 g of KI in 100 ml), 41 cc of 61.5 cc / min each was simultaneously added. The temperature is 40 degrees. Further, an aqueous gelatin solution (containing 35.6 g of gelatin and 284 cc of water) was added, the temperature was raised to 58 ° C., and an aqueous solution of AgNO ₃ (containing 2.4 g of silver nitrate) was added in 30 seconds, followed by aging for 5 minutes.
Using this emulsion as a seed crystal, the following additions were made.

AgNO ₃ aqueous solution (including 47 g of silver nitrate)
Was added in 20 minutes. At this time, pAg was kept at 2.2. After the temperature was lowered to 40 ° C., an aqueous solution of silver nitrate (8.6 g) and an aqueous solution of potassium iodide (8.5 g) were added by a double jet, and subsequently an aqueous solution of silver nitrate (164 g) and an aqueous solution of potassium bromide were added while keeping the pAg at 9.2. did. Thereafter, the mixture was cooled to 35 ° C., washed with water by a conventional flocculation method, 77 g of gelatin was added, pH 6.2, pAg8.
Adjusted to 8. The resulting emulsion was tabular grains having an average equivalent circle diameter of 0.3 μm and an average thickness of 0.15 μm.

(2) Spectral sensitization and chemical ripening The temperature of the emulsion was raised to 62 ° C. and the sensitizing dye Exs-1 described below was added.
5 x 10^-FourMol / mol Ag, Exs-2 1.6 × 10
^-FiveMol / mol Ag, Exs-3 5.5 x 10 ^-FourMol /
Add mol Ag and let stand for 10 minutes, then add sodium thiosulfate
2.6 x 10^-FiveMol / mol Ag, N, N dimethylseleno
Urea 1.1 × 10^-FiveMol / mol Ag, thiocyanate
3.0 x 10^-3Mol / mol Ag, chloroauric acid 8.6
× 10^-6Mol / mol Ag was added and exposed for 1/100 seconds
After aging so that the sensitivity of the time becomes the highest, 3-
(5-Mercaptotetrazole) -benzenesulfonic acid
2.0 × 10 sodium^-FourMol / mol Ag was added.
The emulsion thus obtained is designated as 1-A. Below, the table
-1 Size and amount of chloroauric acid during chemical aging
Emulsions with different values were prepared. Size changes the seed crystal amount
By changing the aspect ratio, the grain growth
It was adjusted by changing the pAg over time. Total surface
The product is shown as a relative value with emulsion 3-a, b, c as 100.
It was The photographic performance is the highest in each emulsion.
Those obtained with are indicated by a circle, and those not obtained are indicated by a cross.
I am doing it. (Experimental change experiment of emulsion mixing) Among the emulsions shown in Table-1
After mixing the emulsions using the 6 types of emulsions that gave the best performance
An experiment was conducted on the change with time. The emulsion mixing ratio is 1:
1. The temperature was 40 ° C. for 30 minutes and 8 hours.

[0026]

[Table 1]

(Preparation and Evaluation of Coated Sample) The emulsion prepared as described above is subjected to heat treatment under the following coating conditions, and a ferromagnetic material for magnetic recording having a thickness of 85 μm and a back surface having a yellow density of 0.12. PEN [2,6-
Naphthalene dicarboxylic acid / ethylene glycol (100
/ 100 molar ratio)] It was coated on a support. Emulsion coating conditions (1) Emulsion layer ・ Emulsion Various emulsions (said color sensitized emulsion) (Silver content 2.1 × 10 ^-2 mol / m ² ) ・ Coupler (1.5 × 10 ^-3 mol / m ^2). )

[0028]

[Chemical 1]

[0029] - tricresyl phosphate (1.10 g / m ²⁾ · Gelatin ^{(2.3g / m 2) (2} ) protective layer, 2,4-dichloro-6-hydroxy -s- triazine sodium salt (0. 08g / m ²⁾ · gelatin (1.8g / m ²⁾ these samples 40 ° C., the relative humidity of 70% 14
After being left for a period of time, exposure was performed for 1/100 second through a yellow filter manufactured by Fuji Film and a continuous wedge, and the following color development processing was performed. (Processing method) Process Processing time Processing temperature Color development 2 minutes 45 seconds 38 ℃ Bleaching 3 minutes 00 seconds 38 ℃ Washing with water 30 seconds 24 ℃ Settling 3 minutes 00 seconds 38 ℃ Washing with water (1) 30 seconds 24 ℃ Washing with water (2 ) 30 seconds 24 ℃ Stabilization 30 seconds 38 ℃ Dry 4 minutes 20 seconds 55 ℃ Next, describe the composition of the treatment solution. (Color developer) (Unit g) Diethylenetriaminepentaacetic acid 1.0 1-Hydroxyethylidene-1,1-diphosphonic acid 3.0 Sodium sulfite 4.0 Potassium carbonate 30.0 Potassium bromide 1.4 Potassium iodide 1. 5 mg hydroxylamine sulfate 2.4 4- [N-ethyl-N-β-hydroxyethylamino] -2-methylaniline sulfate 4.5 Water was added to 1.0 liter pH 10.05 (bleaching solution) ( Unit g) Ethylenediaminetetraacetic acid sodium ferric acid trihydrate 100.0 Ethylenediaminetetraacetic acid disodium salt 10.0 3-Mercapto-1,2,4-triazole 0.08 Ammonium bromide 140.0 Ammonium nitrate 30.0 Ammonia Water (27%) 6.5 ml Water was added to 1.0 liter pH 6.0 (fixing solution) (Unit g) Ethylenediaminetetraacetic acid disodium salt 0.5 Ammonium sulfite 20.0 Ammonium thiosulfate aqueous solution 290.0 ml (700 g / liter) Water was added to 1.0 liter pH 6.7 (Stabilizing liquid) (Unit g) Sodium p-toluenesulfinate 0.03 Polyoxyethylene-p-monononylphenyl ether (Average degree of polymerization 10) 0.2 Ethylenediaminetetraacetic acid disodium salt 0.05 1,2,4-Triazole 1.3 1,4 -Bis (1,2,4-triazol-1-ylmethyl) piperazine 0.75 Water was added and 1.0 liter pH 8.5 Each sample that had been treated was subjected to concentration measurement with a green filter. The sensitivity and fog value of each sample were determined from the measurement results. The sensitivity is represented by the relative value of the reciprocal of the exposure amount that gives a density of fog + 0.2. The results are shown in Table 2.

[0030]

[Table 2]

From the results shown in Table 2, it can be seen that when two kinds of emulsions having different sizes are mixed, the total amount of gold used in each emulsion is very important. That is, for example, when the total gold amount ratio is larger than 1.5 from Samples 101 to 104, the sensitivity after aging becomes extremely low with respect to the fresh sensitivity. Also, samples, 1
It can be seen that when the total gold content ratio is less than 1.3 as in 08 to 110, the fresh sensitivity can be maintained even after 16 hours. In addition, samples 105, 106, 111 and 11 in which emulsions of different sizes having the same aspect ratio are mixed
In No. 2, the sensitivity after a lapse of time cannot be maintained at the fresh sensitivity for the above reason. That is, when mixing two types of emulsions having different sizes, it is important to change the aspect ratio of one emulsion to reduce the surface area ratio.

Example 2 The effect of multi-layer coating of the silver halide emulsion of the present invention is shown.

On the undercoated cellulose triacetate film support, each layer having the composition shown below was coated in multiple layers,
Samples 201-212, which are multilayer color photographing materials, were prepared. (Photosensitive layer composition) The main materials used for each layer are classified as follows; ExC: Cyan coupler UV: UV absorber ExM: Magenta coupler HBS: High boiling point organic solvent ExY: Yellow coupler H: Gelatin Curing agent ExS: Sensitizing dye The numbers corresponding to the respective components indicate the coating amount expressed in units of g / m ² , and for silver halide, the coating amount in terms of silver. However, with respect to the sensitizing dye, the coating amount is shown in mol unit per mol of silver halide in the same layer.

(Sample 201-212) First layer (antihalation layer) Black colloidal silver Silver 0.18 Gelatin 1.40 ExM-1 0.18 ExF-1 2.0 × 10 ^-3 HBS-1 0.20

Second layer (intermediate layer) Emulsion G Silver 0.065 2,5-di-t-pentadecylhydroquinone 0.18 ExC-2 0.020 UV-1 0.060 UV-2 0.080 UV-3 0.10 HBS-1 0.10 HBS-2 0.020 Gelatin 1.04

Third Layer (Low Sensitivity Red Sensitive Emulsion Layer) Mixed Emulsion Used in Example 1 Silver 0.50 ExS-1 6.9 × 10 ^-5 ExS-2 1.8 × 10 ^-5 ExS-3 3.1 × 10 ^-4 ExC-1 0.17 ExC-3 0.030 ExC-4 0.10 ExC-5 0.020 ExC-7 0.0050 ExC-8 0.010 Cpd-2 0.025 HBS-1 0.10 Gelatin 0.87

Fourth Layer (Medium Sensitivity Red Sensitive Emulsion Layer) Emulsion D Silver 0.70 ExS-1 3.5 × 10 ^-4 ExS-2 1.6 × 10 ^-5 ExS-3 5.1 × 10 ^-4 ExC-1 0.13 ExC-2 0.060 ExC-3 0.0070 ExC-4 0.090 ExC-5 0.025 ExC-7 0.0010 ExC-8 0.0070 Cpd-2 0.023 HBS-1 0.10 Gelatin 0.75

Fifth layer (high-sensitivity red-sensitive emulsion layer) Emulsion E Silver 1.40 ExS-1 2.4 × 10 ^-4 ExS-2 1.0 × 10 ^-4 ExS-3 3.4 × 10 ^-4 ExC-1 0.12 ExC-3 0.045 ExC-6 0.020 ExC-8 0.025 Cpd-2 0.050 HBS-1 0.22 HBS-2 0.10 Gelatin 1.20

6th layer (intermediate layer) Cpd-1 0.10 HBS-1 0.50 gelatin 1.10

Seventh Layer (Low Sensitivity Green Sensitive Emulsion Layer) Emulsion C Silver 0.35 ExS-4 3.0 × 10 ^-5 ExS-5 2.1 × 10 ^-4 ExS-6 8.0 × 10 ^-4 ExM-1 0.010 ExM-2 0.33 ExM-3 0.086 ExY-1 0.015 HBS-1 0.30 HBS-3 0.010 Gelatin 0.73

Eighth Layer (Medium Sensitivity Green Sensitive Emulsion Layer) Emulsion D Silver 0.80 ExS-4 3.2 × 10 ^-5 ExS-5 2.2 × 10 ^-4 ExS-6 8.4 × 10 ^-4 ExM-2 0.13 ExM-3 0.030 ExY-1 0.018 HBS-1 0.16 HBS-3 8.0 × 10 ^-3 Gelatin 0.90

9th layer (high-sensitivity green-sensitive emulsion layer) Emulsion E Silver 1.25 ExS-4 3.7 × 10 ^-5 ExS-5 8.1 × 10 ^-5 ExS-6 3.2 × 10 ^-4 ExC-1 0.010 ExM-1 0.030 ExM-4 0.040 ExM-5 0.019 Cpd-3 0.040 HBS-1 0.25 HBS-2 0.10 Gelatin 1.44

10th layer (yellow filter layer) Yellow colloidal silver Silver 0.030 Cpd-1 0.16 HBS-1 0.60 Gelatin 0.60

Eleventh Layer (Low Sensitivity Blue Sensitive Emulsion Layer) Emulsion C Silver 0.18 ExS-7 8.6 × 10 ^-4 ExY-1 0.020 ExY-2 0.22 ExY-3 0.50 ExY-4 0.020 HBS-1 0.28 Gelatin 1.10

12th layer (medium-speed blue emulsion layer) Emulsion D Silver 0.40 ExS-7 7.4 × 10 ^-4 ExC-7 7.0 × 10 ^-3 ExY-2 0.050 ExY-3 0.10 HBS-1 0.050 Gelatin 0.78

13th layer (high-sensitivity blue-sensitive emulsion layer) Emulsion F Silver 1.00 ExS-7 4.0 × 10 ^-4 ExY-2 0.10 ExY-3 0.10 HBS-1 0.070 Gelatin 0.86

14th layer (first protective layer) Emulsion G Silver 0.20 UV-4 0.11 UV-5 0.17 HBS-1 5.0 × 10 ^-2 Gelatin 1.00

Fifteenth layer (second protective layer) H-1 0.40 B-1 (diameter 1.7 μm) 5.0 × 10 ^-2 B-2 (diameter 1.7 μm) 0.10 B-3 0.10 S-1 0.20 Gelatin 1.20

Further, W-1 to W-3, B-4 to B- are added to each layer in order to improve the storability, processability, pressure resistance, antifungal / antibacterial property, antistatic property and coating property. 6, F
-1 to F-17 and iron salt, lead salt, gold salt, platinum salt,
It contains iridium salt and rhodium salt.

[0050]

[Table 3]

In Table 3, (1) Emulsions A to F were prepared according to the examples of JP-A-2-91938.
It is reduction-sensitized during grain preparation using thiourea dioxide and thiosulfonic acid. (2) Emulsions A to F were prepared according to the examples of JP-A-3-237450.
Gold sensitization, sulfur sensitization and selenium sensitization are performed in the presence of the spectral sensitizing dye described in each photosensitive layer and sodium thiocyanate. (3) For the preparation of tabular grains, low molecular weight gelatin is used according to the examples of JP-A 1-158426. (4) Dislocation lines as described in JP-A-3-237450 are observed in tabular grains and normal crystal grains having a grain structure by using a high voltage electron microscope.

[0052]

[Chemical 2]

[0053]

[Chemical 3]

[0054]

[Chemical 4]

[0055]

[Chemical 5]

[0056]

[Chemical 6]

[0057]

[Chemical 7]

[0058]

[Chemical 8]

[0059]

[Chemical 9]

[0060]

[Chemical 10]

[0061]

[Chemical 11]

[0062]

[Chemical 12]

[0063]

[Chemical 13]

[0064]

[Chemical 14]

[0065]

[Chemical 15]

[0066]

[Chemical 16]

These samples were left under the conditions of 40 ° C. and 70% relative humidity for 14 hours, and then exposed to white light through a continuous wedge for 1/100 seconds to carry out the color developing treatment of Example 1. However, the color development time is 3 minutes 15
Went in seconds.

The density is measured through a red filter,
The relative sensitivity was determined by the reciprocal of the exposure dose that gave a density of 1.7. Further, the gamma value was obtained from the slope of the straight line connecting the points of the densities 1.7 and 2.6. The results are shown in Table-4.

[0069]

[Table 4]

From the results shown in Table 4, it can be seen that by using the emulsion of the present invention, it is possible to obtain a light-sensitive material which maintains the soft tone, that is, the breadth of latitude even after the mixing of the emulsion, and the effect of the present invention is remarkable. Met.

Claims (2)

[Claims] 1. A photographic light-sensitive material having at least one silver halide emulsion layer on a support, wherein at least one layer of said silver halide emulsion layer has a different average grain size. Emulsion) and a minimum size emulsion (fine grain emulsion) containing at least two kinds of silver halide emulsions, and the average grain size of the silver halide grains in the coarse grain emulsion is the same as the average grain size of the silver halide grains in the fine grain emulsion. The silver halide photographic light-sensitive material is characterized by having a ratio of the amount of gold used in the fine grain emulsion to the amount of gold used in the coarse grain emulsion of less than 1.5 times the average grain size of the above. 2. The silver halide photographic light-sensitive material according to claim 1, wherein each of the coarse grain emulsion and the fine grain emulsion contains tabular grains having an aspect ratio of 1.5 or more.