JP2995352B2 - How to store photographic compositions - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of preserving a photographic composition prepared by adding a low boiling solvent solution.

[0002]

BACKGROUND OF THE INVENTION The production of silver halide photographic light-sensitive materials (hereinafter simply referred to as "light-sensitive materials") is usually carried out by preparing and processing the following photographic compositions. Gelatin is currently the mainstream of the hydrophilic colloid used for the photosensitive material.

(1) First ripening: Formation of a silver halide suspension composition generally called a photographic emulsion containing silver halide grains suspended in a gelatin sol (2) Desalting (3) Second ripening: Chemical ripening (4) Preparation of coating solution: Add additives necessary for adjusting photographic properties, such as spectral sensitizing dyes, to the second ripened photographic emulsion, and further adjust the liquid properties required for coating such as concentration and viscosity. Perform a photographic coating solution. Coupler or development inhibitor releasing compound (DIR) in emulsion for color photographic materials
When an oil-soluble additive such as described above is added, it is usually dissolved in a high-boiling solvent to form a separate emulsified dispersion composition in a hydrophilic colloid solution, and is added to the photographic emulsion at this stage.

(5) Coating and drying: The prepared coating solution is coated on a support, cooled, set and dried.

[0005] In the industrial production process of photographic materials, the photographic emulsion and the above-mentioned composition and the like before and after the emulsion must be preserved for a certain period of time in the above-mentioned production process from the viewpoint of the operation of ordinary processes and the quality control of the product. Is performed. The preservation treatment is generally directed to a photographic composition such as an emulsified dispersion, a photographic emulsion after desalting or after the second aging, and a coating solution prepared immediately after coating.

[0006] Of these steps, the preservation of the coating solution involves:
(1) The coating solution itself can be inspected during the preservation period, and its photographic characteristics can be confirmed prior to coating. (2) Since preparation at the time of emulsion coating is only a dissolution process, It is possible to prevent deterioration of photographic characteristics due to stagnation of the coating solution, and to reduce the burden on the work and equipment. (3) By blending the stored emulsion, a large amount of uniformity can be obtained. There are advantages such as the ability to prepare a high coating solution, and similar advantages also at the stage of photographic emulsion and emulsified dispersion. It is possible to cope with improvement in functional reliability.

[0007] However, there are many problems associated with the stability of the composition during the storage of the functions to be exhibited. Conventionally, in the preservation treatment of these compositions, low-temperature preservation such as refrigeration or freezing is usually carried out in order to prevent deterioration caused by the progress of chemical reactions and propagation of microorganisms during preservation.

[0008] The lower the temperature, the more effective it is in suppressing the growth of microorganisms and preventing the sensitivity from lowering. However, during storage at low temperatures, the composition changes due to vaporization and precipitation of the contents. Generally, the composition is-
When frozen at around 6 ° C., water separates from the composition system, and when it is thawed and used, the function that it had before freezing is often not restored. For example, in photographic emulsions and coating solutions, fogging increases or viscosity changes due to gelatin deterioration occur, and in emulsified dispersions, pinhole-shaped spots appear on the photographic screen or the viscosity of the dispersion changes.

Regarding the vaporization of the components in the composition,
Low boiling solvents used to dissolve spectral sensitizing dyes and other additives pose problems.

For example, it is known that the sensitizing dye changes the state of aggregation such as the m or j band depending on the amount of the solvent to be dissolved, thereby changing the spectral absorption intensity, and that the absorption wavelength is largely shifted depending on the type of the solvent. On the other hand, the boiling point differs depending on the solvent, and the low-boiling point solvent used for the dye and the additive used to simultaneously coexist in the composition is different, and the shift effect of the solvent used for the additive on the absorption wavelength of the dye is different. Conceivable. Therefore, it is preferable that at least the low boiling solvent is completely removed from the photographic composition at the time of coating.

[0011] Further, the vaporization of the solvent from the surface of the composition during storage causes abnormal distribution of the dried portion, and the dissolution conditions fluctuate, resulting in disturbance of the process.

However, the uncertainties for these properties or processes, which conventionally involve residual low boiling solvents in the composition, remain equivocal.

On the other hand, the composition is stored at a low temperature by spraying or spraying the composition sol into a closed vessel under reduced pressure and cooling to form a gel by rapid cooling (Japanese Patent Laid-Open No. 47-3).
Nos. 0315 and 60-104937), but complete removal of the solvent cannot be expected at such a degree of reduced pressure, and it is practically insufficient.

[0014]

SUMMARY OF THE INVENTION An object of the present invention is to provide a low-temperature preservation method of a photographic composition having good reproducibility of photographic performance and preferable in production technology.

[0015]

The object of the present invention is to reduce the amount of the low boiling point solvent in the photographic composition to 0.1 to 1 with respect to the volume of the photographic composition.
This is achieved by a method for storing a photographic composition, which comprises storing the composition at a low temperature of 0 ° C. to −5 ° C. after suppressing the content to Vol .

In the embodiment of the present invention, the content of the low-boiling solvent during the low-temperature storage is preferably 1 vol% or less, more preferably 0.1 vol% or less, of the photographic composition.

In the present invention, a low-boiling solvent is heated and / or distilled under reduced pressure during and after the preparation of the composition.

Even if the lipophilic sensitizing dye or additive is
It may be mechanically dispersed in a solution of a surfactant or gelatin without using a solvent.

The low-temperature storage may be either refrigeration or freezing.

For the photographic emulsion according to the present invention, known silver halides, for example, known silver halides such as silver bromide, silver chloride, silver iodobromide and silver chlorobromoiodide may be used. it can. The silver halide grain formation, desalting, and chemical ripening processes of the silver halide emulsion according to the method of the present invention are not particularly limited, and can be carried out by a method known in the art.

The chemically-ripened emulsion can be subjected to optical sensitization using a known sensitizing dye. In addition to the above-mentioned high-boiling solvent dispersion, for example, a stabilizer, a sensitizer, a control agent,
Various known photographic emulsion additives such as a stain inhibitor are optionally added to prepare a coating solution according to the present invention.

The compositions according to the present invention, such as the emulsified dispersions, photographic emulsions and coating solutions, are cooled, set, and refrigerated at a temperature ranging from 0 ° C. to the freezing point of each composition. The refrigeration temperature is preferably a temperature close to the freezing point of the liquid to be stored, and is substantially in the range of -3C to -5C. When the refrigeration temperature is higher than 0 ° C., the fog increase, the decrease in the photographic properties of the emulsion including sensitivity fluctuation, and the prevention of propagation of microorganisms are not sufficient,
When the temperature is below the freezing point, pinholes are generated due to coarsening of the dispersed oil droplets containing the additive. It is preferable to rapidly cool the composition.For example, a composition in a liquid state described in JP-A-60-104937 is rapidly cooled by boiling under reduced pressure to remove latent heat of vaporization and gelation. The method described above can be preferably used.

In the method of the present invention, before the cooling and storage of the coating solution, the addition of all the additives necessary for preparing the coating solution in addition to the high-boiling solvent dispersion and the adjustment of the emulsion concentration and the viscosity are performed. Although preferable, an additive such as an immediate-acting hardening agent, which has a risk of proceeding even during refrigeration, can be added at the time of dissolution during coating.

The composition stored by the above-mentioned method of the present invention is subjected to necessary treatments as necessary, finished into a coating solution, coated on a support, and dried. For the coating, a known support and a coating method can be used. The dissolution of the emulsion after storage is preferably carried out as rapidly as possible while avoiding local temperature rise.

[0025]

Next, the present invention will be described in detail with reference to examples.

Example 1: Silver halide emulsion: A core / shell type silver iodobromide having an average particle size of 0.38 μm was prepared by a double jet method, and after desalting by a conventional method, sodium thiosulfate and chloroauric acid were added. Chemical ripening was performed to obtain optimum sensitivity.

Each of the emulsions prepared in the form of a sol has a
^The sensitizing dyes I and II were added in an amount of 5 × 10 ^-4 mol and 1 × 10 ^-4 mol per mol of silver of the emulsion, and the mixture was spectrally sensitized to green light sensitivity.

Further, a coupler dispersion having the following formulation was added to the emulsion so that 0.5 g of a magenta coupler and 0.01 g of a colored magenta coupler per 1 g of silver contained in the emulsion were added.

Coupler dispersion M-1 7.5 g CM-1 0.15 g Tricresyl phosphate 6 g 4% gelatin solution 375 ml Dispersing aid Su-1 10% solution 25 ml

[0030]

Embedded image

[0031]

Embedded image

The negative ortho-emulsion and the magenta coupler dispersion were mixed in a closed vacuum mixer equipped with a heating jacket, heated to 60 ° C. with a jacket and reduced in pressure to remove methanol.

In this operation, about 5% by volume of methanol can be reduced to 0.1% by volume.

Here, the remaining methanol amount is 5, 3 and 0.1 vol%.
Was prepared.

Subsequently, a vacuum setting device (JP-A-60-104937)
No.), and refrigerated at 0 ° C. for 50 days, and then dissolved to prepare a coated sample.

The coated sample was exposed according to a conventional method, developed under the following conditions, and measured for specific sensitivity and pinhole.
The coating properties were observed and the results are shown in Table 1. Further, regarding the specific sensitivity, a graph relating to the storage stability is shown in FIG.

The pinhole is the number of large oil droplets having a diameter of 20 to 100 μm per m ² when the wet film thickness is 30 μm.

The coated samples were exposed to wedges using a sensitometer, developed, and the sensitivity and fog of each sample were measured. The development conditions were as follows.

[Processing solution and processing conditions] Processing step (38 ° C.) Color development 3 minutes 15 seconds Bleaching 6 minutes 30 seconds Water washing 3 minutes 15 seconds Fixing 6 minutes 30 seconds Water washing 3 minutes 15 seconds Stabilization 1 minute 30 seconds Drying The composition of the processing solution used in the processing step is shown below.

Color developing solution 4-amino-3-methyl-N-ethyl-N- (β-hydroxyethyl) aniline / sulfate 4.75 g anhydrous sodium sulfite 4.25 g hydroxylamine 1/2 sulfate 2.0 g anhydrous potassium carbonate 37.5 g Potassium bromide 1.3 g Nitrilotriacetic acid trisodium salt (monohydrate) 2.5 g Potassium hydroxide 1.0 g Add water to make 1 liter (pH = 10.02) Bleaching solution Ethylene (III) ammonium ethylenediaminetetraacetate 100.0 g Ethylenediaminetetraacetic acid diammonium salt 10.0 g Ammonium bromide 150.0 g Glacial acetic acid 10.0 g Add water to make 1 liter, and adjust the pH to 6.0 using aqueous ammonia.

Fixing solution Ammonium thiosulfate 175.0 g Anhydrous ammonium sulfite 8.6 g Sodium metasulfite 2.3 g Water was added to 1 liter, and the pH was adjusted to 6.0 with acetic acid.

Stabilizing solution Formalin (37% aqueous solution) 1.5 ml KONIDAX (manufactured by Konica Corporation) 7.5 ml Make up to 1 liter by adding water.

[0043]

[Table 1]

As is clear from the table, the remaining amount of methanol is 0.1 vol.
In% preservation, the specific sensitivity does not decrease and the pinhole hardly increases. In addition, there is no problem in applicability.

In addition, since vaporization of the solvent is neglected in the coating process, explosion-proof equipment is not required, and equipment cost is reduced.
Furthermore, Marangoni unevenness almost disappears.

On the other hand, in the samples having the remaining methanol contents of 3 and 5 vol%, precipitates were observed after storage for 50 days together with deterioration of the characteristics.

[0047]

According to the present invention, there is no danger of the drying process due to the evaporation of the solvent, and the production process is excellent in photographic performance, coating properties and other productivity.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the storage period, the remaining methanol vol%, and the specific sensitivity.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-193134 (JP, A) JP-A-1-216352 (JP, A) JP-A-4-229854 (JP, A) JP-A-2- 190848 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) G03C 1/025

Claims (1)

(57) [Claims] 1. The amount of a low boiling solvent in a photographic composition is determined
0.1% to 1% by volume based on the volume of the composition for
A method for storing a photographic composition, wherein the composition is stored at a low temperature of from -5 to -5 ° C.