JP3309979B2 - Aqueous mixture of spectral sensitizing dyes for photographic emulsions - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method for producing a concentrated dye-water composition for spectral sensitization of photographic emulsions.

Background of the Invention Dyes for spectrally sensitizing silver halide emulsions are known to be practically insoluble in water. Accordingly, such dyes, as well as other photographic additives that can be adsorbed on the silver salt grain surface, include photographic silver halide emulsions in the form of a solution in a suitable water-miscible solvent such as methyl alcohol, dimethylformamide, and the like. It has been added to.

However, spectral sensitizing dyes are difficult to dissolve in common solvents. Therefore, large amounts of solvents are often required to sufficiently dissolve such additives.
This creates a serious problem because the presence of residual solvent generally causes diffusion and migration of the spectral sensitizing dye into the emulsion. Furthermore, even the slightest residue of the solvent promotes the recrystallization process in the photographic layer, and consequently not only the dyes and other additives added with the solvent, but also the other additives in the emulsion. Adversely affect Further, when a residue of a polar organic solvent miscible with water remains in a silver halide emulsion, particularly in a silver-rich emulsion having a high silver filling concentration, the residual solvent significantly enhances the stability of the casting emulsion. Degradation, resulting in reduced stability during processing, such as phase separation between the hydrophilic and hydrophobic phases before casting, agglomeration, and fusion and flocculation.

Additives which need not be retained on the silver halide crystal surface by adsorption after addition to the photographic emulsion have long been incorporated into the silver halide emulsion in the form of dispersions. For this purpose, the additives are usually dissolved in a suitable solvent, which is generally immiscible with water, in the presence of an oil former and a wetting agent, and then emulsified in an aqueous gelatin solution.
The low boiling solvents commonly used for this purpose are then removed from the emulsion and the resulting dispersion is added to a photographic silver halide emulsion.

Unfortunately, even when using low boiling solvents, it is difficult to completely remove the solvent from the resulting dispersion, especially when using polar solvents. Polar solvents, especially polar protic solvents, can only be removed from the gelatin dispersion by heating, but this adversely affects the stability of the sensitizing dye molecule. Alternatively, the use of vacuum to remove the solvent often results in significant foaming.

GB 1,570,362 describes a method for preventing the detrimental effects of using a water-miscible or immiscible organic solvent to add a substantially insoluble additive to a silver halide emulsion and dispersion. Is to sand mill such additives to a particle size of less than 1 micron in water in the presence of a surfactant that produces a surface tension in water of 38 dynes / cm or more when used in an amount of 1 g / g.

A similar method is disclosed in U.S. Patent No. 4,006,025, which teaches that the sensitizing dye is milled or homogenized at elevated temperatures in the presence of a surfactant that is at least partially soluble. This method is complicated and the use of surfactants increases the finishing time.

The method described in U.S. Pat. No. 4,474,872 also requires milling, but precludes the use of surfactants only when the pigment is mechanically milled to a fine particle size (1 micron or less). Teaches what you can do. Extremely high temperatures (60-80 ° C.) are used in the production of dispersions, and processing conditions such as pH are tightly controlled. Such an approach only eliminates one problem, but creates a number of other problems.

SUMMARY OF THE INVENTION In accordance with the present invention, a sensitizing dye having a solubility in water of at least 0.005% by weight is added, with stirring, at a temperature of from 20C to 50C, in an amount exceeding the amount soluble in water or a water-polymer medium. Spectral sensitizing the photographic emulsion in the absence of an organic solvent or surfactant, comprising adding to the water or water-polymer medium at a concentration and continuing stirring for 30 minutes to 5 hours or more. A method for producing a concentrated dye-water composition, wherein the sensitizing dye has the structure III, VII, or I described below.
A method is provided which is a sensitizing dye of X, X, XI or XII.

According to the present invention, sensitizing dyes having a solubility in water of at least 0.005% by weight are added to gelatin at a dye concentration exceeding the amount soluble in the water-polymer medium while stirring at a temperature of 20 ° C. to 50 ° C. For spectrally sensitizing a photographic emulsion in the absence of an organic solvent or surfactant, comprising adding to a water-polymer medium containing and stirring for 30 minutes to 5 hours or more. A method for producing a concentrated dye-water composition is provided.

The method of the present invention is simple, useful and flexible. This method does not require the use of solvents, surfactants, pulverization of the dye to very fine particle size, the use of high temperatures, pH control, and the like.

The concentration of dye used in this method generally exceeds the amount of dye soluble in the dispersing medium at the manufacturing, use or storage temperatures. Preferably, an amount of the dye ranging from about 0.5 to about 5% by weight based on the total weight of the mixture is used.

The method of the present invention has a solubility in water of at least about 0.00
It is preferred to use 5% by weight of the cyanine dye. Preferred dyes have the formula Wherein Z ₁ and Z ₂ each independently represent an atom necessary to complete a substituted or unsubstituted heterocyclic nucleus; each L independently represents a substituted or unsubstituted methine group; A positive integer of 1 to 4, p and q each independently represent 0 or 1, X represents a cation necessary to balance the charge of the molecule,
And A 'each independently represent a divalent alkyl or substituted alkyl linking group.

More preferred is the formula Wherein n is 0 or 1; X ₁ and X ₂ each independently represent oxygen or sulfur; Q ₁ , Q ₂ , Q ₃ and Q ₄ each independently represent halogen, alkyl, Represents alkoxy or β
Or containing the atoms necessary to form a linear naphtho-fused ring; R ₁ and R ₂ each independently represent a sulfoalkyl or substituted sulfoalkyl group; X ⁺ is sodium, hydrogen, triethylammonium or ethyl A cation such as pyridinium].

DETAILED DESCRIPTION OF THE INVENTION The process of the present invention provides a concentrated, solvent-free, dispersant-free concentrated sensitizing dye-water composition which is nevertheless resistant to settling. It is. If some sedimentation occurs, the composition becomes homogeneous again with a little stirring or mixing.

Generally, a solid sensitizing dye powder that is somewhat soluble in water is placed in an "aqueous medium", preferably containing gelatin (this term includes polymer-containing aqueous media (water-polymer medium)).
At higher dye concentrations than will dissolve in the medium, the composition is mixed at the temperature, pressure or other conditions of processing, storage or use. About 0.5 based on the total weight of the components of the composition
Amounts ranging from to about 5% by weight are preferred. This method is simpler, faster, more flexible and more flexible than prior art methods, since it can be performed in the absence of solvents or surfactants.

Preferably, the medium to which the dye is added is heated to a production temperature in the range of about 20 ° C. to about 50 ° C., and throughout the addition and mixing of the dye.
Keep at the same temperature. When using gelatin, about 40
It is preferred to use temperatures above 0 ° C, but lower temperatures can be used for other polymers. This method
Since different temperatures can be used for addition and mixing,
Flexible.

After completion of the addition of the dye, the mixing or stirring is continued until little evidence of the initial particles of the dye powder can be observed. This generally requires about 30 minutes to about 5 hours.

The composition can be mixed or agitated by any suitable means using any suitable apparatus, including various shapes of magnetically driven stir bars and propellers or Cowles-type electric shaft stirrers. To calculate the preferred stirring volume to use, JYOl
“Fluid Mixing Technology”, McGraw-Hi by dshue
The formula provided in ll, New York, 1983, p. 83 can be used: p / kg = (diameter) ⁵ × (RPM) ³ / batch dimension [where diameter = Cowles or other wing diameter (in inches) ) And batch dimensions = kg].

Best results in terms of minimizing the number of undispersed dye particles are obtained when p / kg> 50 × 10 ⁹ .

The process of the present invention provides a spectral sensitizing dye, especially a spectral sensitizing cyan dye, in which the solubility of the dye in water is only about 0.005% by weight, despite the absence of solvents, dispersants, surfactants or wetting agents. Can be used. Preferred dyes have the formula [Wherein, Z ₁ and Z ₂ each independently represent an atom necessary to complete a substituted or unsubstituted heterocyclic nucleus; each L independently represents a substituted or unsubstituted methine group; A positive integer of 1 to 4, p and q each independently represent 0 or 1, and X
Represents any suitable cation that balances the charge on the molecule, and A and A ′ each independently represent a divalent alkyl or substituted alkyl linking group.

More preferred is the formula Wherein n is 0 or 1; X ₁ and X ₂ each independently represent oxygen or sulfur; Q ₁ , Q ₂ , Q ₃ and Q ₄ each independently represent halogen, alkyl, alkoxy. R ₁ and R ₂ each independently represent a sulfoalkyl or substituted sulfoalkyl group; X ⁺ is sodium, Hydrogen, a cation such as triethylammonium or ethylpyridinium].

Most preferred for use in the practice of the present invention include Structures I-XII.

Solvent- and dispersant-free dye-water compositions containing about 0.5 to about 5% by weight of a dye as defined herein, prepared by the method of the present invention, are resistant to settling. . Similar compositions made by prior art methods or containing other dyes may require solvents or surfactants to produce similar results, or may require other complex and difficult manufacturing methods. I need.

Concentrated sensitizing dye of the present invention for spectral sensitization of photographic emulsion
The water composition can be manufactured by any suitable method. However, according to the present invention, the concentrated dye-water composition is preferably prepared by first mixing the gelatin and water and then heating to produce the initial gelatin solution. While heating, stirring or mixing or otherwise stirring the gel solution, the sensitizing dye of the present invention is added gradually and uniformly, preferably in the form of a powder, to the surface of the stirred mixture. After completion of the addition of the sensitizing dye, stirring is continued for a period of time, generally from about 30 minutes to about 5 hours or more, as needed, to provide the concentrated dye of the invention.
Produce a water composition.

More specifically, a dispersion of the salt of the sensitizing dye of the present invention is prepared in a stainless steel can having a diameter of about 20 cm and a height of 24.75 cm to which about 300 g of dry deionized bone gelatin and about 4675 g of distilled water have been added. The mixture was placed in the refrigerator overnight to swell the gelatin. The resulting gel-water mixture was then melted at a temperature of about 50 ° C and kept at that temperature until the gelatin was dissolved.

While maintaining the temperature at 50 ° C., introduce a 10 cm Cowles-type stirrer driven by a motor, the stirrer wings located in the center of the can are parallel to the bottom of the can and from the bottom of the can about
7.6cm. The stirring speed is maintained at about 500 rpm while slowly and uniformly adding about 25 g of powder of structure IX near the vortex on the surface of the stirring mixture over about 2 minutes. The powder is prepared by grinding the pigment with a mortar and pestle until the pigment passes through a 1 mm opening sieve.

Next, lower the agitator blade to about 5 cm from the bottom of the can,
To about 660. Stirring is continued for about 1 hour. The final dye dispersion is about 0.5% dye by weight based on the weight of the total dispersion
And about 6% by weight of gelatin.

The dye composition of the present invention can contain a polymer binder or a protective colloid which can be used in the photographic emulsion layer of the photographic light-sensitive material intermediate layer. While it is advantageous to use gelatin, other hydrophilic colloids can be used alone or with gelatin. Lime-treated or acid-treated deionized gelatin can be used.

Any suitable silver halide, for example, silver bromide, silver iodobromide, silver chlorobromide, silver chloride, and the like can be used in the photographic emulsion layer of the photographic material sensitized according to the present invention. Certain types of silver halide grains and photographic emulsions as described in U.S. Patent No. 4,741,995, the entire disclosure of which is incorporated herein by reference, can be used.

Photographic emulsions can be matured in the presence of cadmium salt, zinc salt, lead salt, thallium salt, iridium salt or its complex salt, rhodium salt or its complex salt, iron salt or its complex salt, etc. The silver halide crystals can be produced by any suitable method, including an acidic method, a neutral method, and an ammonia method, using a controlled jet method.

Silver halide emulsions are usually prepared by sulfur sensitization using compounds such as thiosulfates, thioureas, mercapto compounds and rhodanin containing sulfur which can react with active gelatin or silver; stannous salts, amines, hydrazines Derivatives,
Formamidine-sulfinie
acid), by a reduction sensitization method using a reducing substance such as a silane compound or the like; a noble metal sensitization method using a noble metal compound such as a complex salt of platinum, iridium, palladium or the like, and a group VIII metal of the periodic table including a gold complex salt. Depending on the method of sensitization, they may be chemically sensitized alone or in combination with each other.

Photographic emulsions can contain various compounds to prevent fog formation or stabilize photographic properties during manufacture, storage or processing. For example, antifoggants or stabilizers include azoles such as benzothiazolium salts, nitroimidazole, nitrobenzimidazole, chlorobenzimidazole, bromobenzimidazole, mercaptothiazole, mercaptobenzothiazole, mercaptobenzimidazole, mercaptothiadiazole, Aminotriazole, benzotriazole, nitrobenzotriazole, mercaptotetrazole, especially 1-phenyl-5-mercaptotetrazole; mercaptopyrimidine, mercaptotriazine, thioketo compounds such as oxazolinethione, azaindene such as triazaindene, tetraazaindene, In particular, 4-hydroxy-substituted 1,3,3a, 7-tetraazaindene, pentaazaindene, benzenethio-sulfonic acid Benzenesulfinic acid, benzenesulfonic acid amide.

Various surfactants are incorporated as coating aids in photographic emulsions or other hydrophilic colloid layers of the photographic material sensitized according to the present invention to prevent charging, improve slip properties, emulsify and disperse. Promotes adhesion, prevents adhesion, accelerates development,
Photographic properties such as high contrast and sensitization can be improved.

The photographic emulsion layer may also include a polyalkylene oxide or an ether, ester, amine, or similar derivative thereof, a thioether compound, thiomorpholine, a quaternary ammonium salt compound, a urethane derivative to increase sensitivity or contrast or promote development. , Urea derivatives, imidazole derivatives, and 3-pyrazolidones.

A photographic emulsion layer or other hydrophilic colloid layer can be admixed with a water-insoluble or only slightly aqueous synthetic polymer dispersion to improve dimensional stability and the like. Some synthetic polymers that can be used include homo- or copolymers such as alkyl acrylates or methacrylates, alkoxyalkyl acrylates or methacrylates, glycidyl acrylates or methacrylates, acrylamides or methacrylamides, vinyl esters such as vinyl acetate, acrylonitrile, olefins, styrene, and the like. And acrylic acid, methacrylic acid, α, β-unsaturated dicarboxylic acid, hydroxyalkyl acrylate or methacrylate,
Sulfoalkyl acrylate or methacrylate,
Copolymers with styrene sulfonic acid and the like can be mentioned.

In addition to the concentrated dye-water compositions of this invention for spectrally sensitizing photographic emulsions prior to coating on a support, see, for example, U.S. Pat. Nos. 2,933,390 and 3,635,721, the contents of which are hereby incorporated by reference. Aminostyryl compounds substituted with nitrogen-containing heterocyclic groups, including those described in US Pat. No. 3,743,510, the contents of which are incorporated herein by reference. Other sensitizing dyes which do not themselves produce spectral sensitization but produce supersensitization, such as aromatic organic acid-formaldehyde condensates, cadmium salts, azaindene compounds and the like, can be used.

The concentrated dye-water sensitizing composition of the present invention can be used in a layer containing a multi-layer multicolor photographic material sensitive to at least two different spectral wavelength ranges on a support. Multilayer natural color photographic materials generally comprise at least one red-sensitive silver halide emulsion layer,
The support has at least one green-sensitive silver halide emulsion layer and at least one blue-sensitive silver halide emulsion layer on a support. The order of the layers can be varied as needed. Usually, a cyan-forming coupler is provided in the red-sensitive emulsion layer,
There is a magenta-forming coupler in the green-sensitive emulsion layer and a yellow-forming coupler in the blue-sensitive emulsion layer. Different combinations can be used if desired.

Any suitable dye-forming coupler, i.e., a compound capable of forming a color upon oxidative coupling with an aromatic primary amine developing agent, such as a phenyl-diamine derivative, an aminophenol derivative, etc., during the color development process is required. It can be incorporated in the same or different photographic silver halide emulsion layers depending on the case. Some examples of such couplers include 5-
Magenta couplers such as pyrazolone couplers, cyanoacetylcoumarone couplers and open-chain acylacetonitrile couplers; yellow couplers such as acylacetamide couplers including benzoylacetanilides, pivaloylacetoanilides; cyan couplers such as naphthol couplers and phenol couplers Is mentioned. Preferably, non-diffusible couplers or polymer couplers containing a hydrophobic or ballast group in the molecule are used. They can be 4-equivalent or 2-equivalent with respect to silver ions. Colored couplers that can exert a color modifying effect or couplers that can release the development inhibitor during the course of development or DIR couplers can also be used. Two or more couplers can also be used.

The photographic material can include an inorganic or organic hardener in its emulsion layer or other hydrophilic colloid layer. For example, chromium salts, such as chrome alum, chromium acetate and the like;
Aldehydes such as formaldehyde, glyoxal, glutaraldehyde and the like; N-methylol compounds such as dimethylolurea and methyloldimethyl-hydantoin; dioxane derivatives such as 2,3-dihydroxydioxane; active vinyl compounds such as 1,
3,5-Triacryloylhexahydro-s-triazine and the like; mucohalic acids such as mucochloric acid, mucophenoxy-chloroic acid and the like can be used alone or in combination.

When a dye, an ultraviolet absorber and the like are mixed in the hydrophilic colloid layer of the photographic light-sensitive material, they can be mordanted with a cationic polymer or the like. Photosensitive materials also include hydroquinone derivatives as color fog inhibitors,
Aminophenol derivatives, gallic acid derivatives, ascorbic acid derivatives and the like can be included.

Examples of the dye that can be mixed with the hydrophilic colloid layer of the photographic light-sensitive material of the present invention include a benzotriazole compound substituted with an aryl group, 4-thiazolidone, benzophenone, cinnamate, butadiene, and a benzoxazole compound. Ultraviolet absorbing couplers such as α-naphthol type cyan dye forming couplers and ultraviolet absorbing polymers can also be used. Such UV absorbers can also be mordant in certain layers if desired.

Photographic elements made using the spectrally sensitized emulsions of this invention can contain a water-soluble dye in the hydrophilic colloid layer as a filter dye or for other purposes such as prevention of irradiation. Some of such suitable dyes include oxonol, hemioxonol, styryl, merocyanine, cyanine, azo dyes, and the like. Oxonol, hemioxonol, and merocyanine dyes are particularly useful.

In addition to the color image stabilizer, any suitable anti-fading agents can be used alone or in combination with one another. Some suitable anti-fading agents include hydroquinoline derivatives, gallic acid derivatives, p-oxyphenol derivatives, bisphenols and the like.

Silver halide photographic emulsions sensitized according to the present invention may also be any suitable hardeners, surfactants, optical brighteners, physical property modifiers such as humectants, water dispersants, etc .; And various other additives used in photography, including condensates of and formalin.

The silver halide emulsion sensitized according to the present invention can be coated on any suitable support and dried to produce a light-sensitive silver halide photographic element. Some suitable supports include paper, glass, cellulose acetate, cellulose nitrate, polyester, polyamide, polystyrene, etc., or two or more such as paper and laminates of polyolefins, eg, polyethylene, polypropylene, etc. Laminated articles of the support are included. The support can be subjected to various surface modification treatments for improving adhesion to the silver halide emulsion, such as undercoating and electron impact treatment.

Coating and drying of the silver halide photographic emulsion on the support can be usually carried out by dip coating, roller coating, multi-slide hopper coating, flow coating and the like, followed by drying.

Layers sensitized to other wavelengths, such as green-sensitive and red-sensitive silver halide emulsion layers, interlayers, protective layers, filter layers,
By combining various photographic layers from antihalation layers, backing layers, and the like, light-sensitive color photographic elements can be formed. In such a case, each photosensitive emulsion layer can be composed of two emulsion layers having various photographic speeds.

Although the present invention has been described in detail above, those skilled in the art will appreciate that such detailed description is merely illustrative and that it does not depart from the spirit and scope of the invention other than as set forth in the appended claims. Needless to say, it can be changed by the

Continuation of the front page (56) References JP-A-5-297496 (JP, A) JP-A-3-219232 (JP, A) JP-A-4-139443 (JP, A) JP-A-58-105141 (JP) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03C 1/83 G03C 1/06 502

Claims (6)

(57) [Claims] (1) While stirring at a temperature of 20 ° C to 50 ° C,
A sensitizing dye having a solubility in water of at least 0.005% by weight,
Add to the water or water-polymer medium at a dye concentration greater than the amount soluble in the water or water-polymer medium, and add
A method of making a concentrated dye-water composition for spectrally sensitizing a photographic emulsion in the absence of an organic solvent or a surfactant, comprising continuing stirring for hours or more. Dye has the structure: Manufacturing method. 2. A process according to claim 1, wherein 0.5 to 5% by weight, based on the total weight of the mixture, of the dye is added to the water or water-polymer medium. 3. The process according to claim 1, wherein agitation (p / kg) greater than 50 × 10 ⁹ is used. 4. A process as claimed in claim 1, wherein the pigment is a powder which can be passed through a 1 mm sieve when added to water or a water-polymer medium. 5. While stirring at a temperature of 20 ° C. to 50 ° C.,
A sensitizing dye having a solubility in water of at least 0.005% by weight,
A dye concentration greater than the amount soluble in the water-polymer medium is added to the gelatin-containing water-polymer medium and added for 30 minutes to 5 minutes.
A process for the preparation of a concentrated dye-water composition for spectrally sensitizing a photographic emulsion in the absence of an organic solvent or a surfactant, comprising continuing stirring for an hour or more. 6. A concentrated pigment-water composition product according to any one of claims 1 to 5.