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Publication numberUS3615534 A
Publication typeGrant
Publication dateOct 26, 1971
Filing dateSep 23, 1968
Priority dateSep 22, 1967
Also published asDE1797383A1, DE1797383B2, DE1797383C3
Publication numberUS 3615534 A, US 3615534A, US-A-3615534, US3615534 A, US3615534A
InventorsOhmura Kunioki, Tajima Tatsuya
Original AssigneeFuji Photo Film Co Ltd
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Photographic silver halide light-sensitive elements useful in preventing yellow fog
US 3615534 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

United States Patent Inventors Tatsuya Tajima;

Kunioki Ohmura, both of Kanagawa, Japan Appl. No. 761,858

Filed Sept. 23, 1968 Patented Oct. 26, 1971 Assignee Fuji Photo Film Co., Ltd.

Kanagawa, Japan Priority Sept. 22, 1967 Japan 42/6092] PHOTOGRAPHIC SILVER HALIDE LIGHT- SENSITIVE ELEMENTS USEFUL IN PREVENTING YELLOW FOG 4 Claims, No Drawings US. Cl 96/67, 96/109 Int. Cl G03c l/76, G030 3/00, G03c l/34 Field of Search 96/67, 109

[56] References Cited UNITED STATES PATENTS 3,144,336 8/1964 l-lerz 96/109 3,466,173 9/1969 Ishikawa 96/109 FOREIGN PATENTS 948,442 2/1964 Great Britain Primary Examiner-Norman G. Torchin Assistant ExaminerMary F, Kelley Attorney- Sughrue, Rothwell, Mion, Zinn & MacPeak ABSTRACT: A photographic silver halide light-sensitive element comprising a support having thereon at least one layer containing a silver halide, wherein one colloid containing layer of said element contains: a) a compound of the formula M10 0r M10 wherein M is a hydrogen atom, an alkaline metal atom or ammonium group, and b) at least one of the following: unsubstituted benzenesulfinic acid, substituted benezenesulfinic acid and salts thereof; This element exhibits a marked reduction in the amount of yellow fog which is formed after storage and/0r development.

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a photographic silver halide light-sensitive element in which the formation of yellow fogs is reduced.

Description of the Prior Art An exposed photographic silver halide light-sensitive element is usually successively processed in a developing bath, a stopping bath and a fixing bath. In this case, a thiosulfate, a solvent for a silver halide which is contained in the fixing bath, is frequently intermixed in a developer. Also, in the case of processing an exposed photographic silver halide light-sensitive element in a monobath for development and fixing simultaneously, a thiosulfate which is a solvent for a silver halide is sometimes incorporated in the monobath.

When photographic silver halide light-sensitive elements are developed in such a developing bath (or a monobath for development and fixing simultaneously) containing a solvent for silver halide, yellow fogs are-produced, the extent of the fogs depending upon the kind of the light-sensitive element.

In particular, in photographic printing papers, the formation of yellow fogs is more developed than in other photographic silver halide light-sensitive elements, and to prevent the formation of fogs, various antifoggants have been used.

In most cases, yellow fogs in photographic silver halide light-sensitive elements are caused by fine silver particles or silver sulfide deposited in any water-permeable colloid layer used in forming the photographic silver halide light-sensitive elements, not generally in baryta layers or emulsion layers thereof, or in water-permeable papers. The reason for the formation of such yellow fogs is as follows:

When a photographic silver halide light-sensitive element is processed in a developer containing a solvent for a silver halide, such as a thiosulfate, and when a material capable of forming a nucleus for reducing water-soluble silver ions to metallic silver, such as colloidal sulfur, silver or silver sulfide is present in a baryta layer or an emulsion layer thereof is present, water-soluble silver ions are reduced into metallic silver by reducing agents (for example a developing agent) in the developer, and these deposit on the aforesaid nuclei, thus forming the yellow fogs.

The yellow fogs thus formed can be generally divided into two types, according to their method of formation. One method is where the formation of yellow fogs is observed when a photographic silver halide light-sensitive element is developed in a developer containing a solvent for silver halide, just after the preparation thereof. A second method is where the formation of yellow fogs is not observed when a photographic silver halide light-sensitive element is developed in a developercontaining a solvent for silver halide (just after the preparation thereof), but is observed when a photographic silver halide light-sensitive element is subjected to the same processing after it is stored under various conditions.

The former is the situation when a material capable of being a nucleus for reducing water-soluble silver ions to metallic silver is already present in a baryta paper as a support for a photographic silver halide light-sensitive element, or else is present in a silver halide light-sensitive emulsion layer, a baryta paper, or a paper for a photographic silver halide lightsensitive element at the preparation thereof. The latter case is where a material capable of forming a nucleus for reducing water-soluble silver ions to metallic silver is formed in the emulsion layer, the baryta layer of the support of the photographic element, after it has been stored under various conditions. For example, when photographic printing papers are packed and stored for a long period of time, yellow fogs are formed, in particular at the edges of the printing papers or at the uppermost sheet of the photographic printing paper. This shows that the formation of a nucleus utilized for reducing water-soluble silver ions to metallic silver is particularly great at portions which are liable to be contacted by the atmosphere.

SUMMARY OF THE INVENTION It has been found that a photographic silver halide-sensitive element which contains at least one colloid layer which contains a compound capable of forming iodate ions will exhibit a marked reduction in the amount of yellow fogs which may be formed therein. To prolong the effect of the iodate-forming compound after storage, benzenesulfinic acids and salts thereof, may be added.

Representative compounds capable of forming iodate ions are iodic acid, periodic acid and salts thereof.

Various substituted benzenesulfinic acids, and salts thereof are described in the specification.

Representative colloidal materials wherein the compound of the present invention may be incorporated include emulsion layers, protective layers and baryta layers.

Thus, an object of this invention is to prevent the formation of yellow fogs in photographic silver halide light-sensitive elements, and in particular to prevent the formation of yellow fogs in photographic silver halide light-sensitive elements when they are stored or allowed to stand for long periods of time under various conditions.

Another object of this invention is to provide a photographic silver halide light-sensitive element in which the formation of yellow fogs is effectively reduced or prevented.

DESCRIPTION OF THE PREFERRED EMBODIMENTS These objects of this invention can be attained by incorporating in a support paper for photographic printing paper or in at least one layer of the colloidal layers or emulsion layers formed on a support for photographic silver halide light-sensitive elements, a compound capable of forming iodate ions (hereinafter such a compound is called an iodate compound) together with, if necessary, an unsubstituted or substituted benzenesulfinic acid, or a salt thereof.

In the claims and the specifications of this invention, the colloid layers include every layer which contains colloidal materials for photographic silver halide light-sensitive elements, such as, emulsion layers, protective layers, and baryta layers. Thus, the factors which cause yellow fogs are, as mentioned above, due to the properties specific to the material which is used. However, it is believed that lower molecular weight materials contained in a colloid layer or a paper base move freely through each layer when each colloid layer of the photographic silver halide light-sensitive element is swollen in a processing bath. In fact, the aforesaid material (such as an iodine compound, unsubstituted or substituted benzenesulfinic acid, or a salt thereof) may be effectively incorporated in any of the colloid layers and the paper base, and thus may, in effect, be incorporated in any layer in the present invention.

A compound capable of forming iodate ions (l0 that is an iodate compound, is generally a compound as iodic acid, periodic acid or a salt thereof, represented by M10, or MlO wherein M represents a hydrogen atom, an alkali metal or an ammonium group. As illustrative examples of such compounds, there are ammonium iodate, iodic acid, sodium iodate, periodic acid, potassium periodate, ammonium periodate, and the like.

The unsubstituted or substituted benzenesulfinic acids or salts thereof, may generally be represented by the general formula:

wherein M represents a hydrogen atom, an alkali metal or ammonium group, and X represents hydrogen, a halogen atom, an alkyl group having 1-3 carbon atoms, or an amino group. Illustrative examples of such compounds are sodium benzenesulfinate, sodium p-toluenesulfinate, sodium pchlorobenzenesulfinate, and sodium p-aminobenzenesulfinate.

The mechanism of the iodate compound of this invention for preventing the formation of yellow fogs has not yet been clarified, but the following is offered as a nonlimitative possible explanation. The yellow fogs form in the silver halide emulsion layer of a photographic silver halide light-sensitive element or at the interface between the silver halide emulsion layer and an adjacent layer thereof. Hence, the yellow fogs are considered to be formed through a stage where physical development nuclei are formed or present. Thus, yellowish developed silver as formed, utilizing the physical development nuclei as the development nuclei when the photographic silver halide light-sensitive element is developed in a developing bath containing a solvent for a silver halide. It is believed proper to consider the physical development nuclei as very fine particles of metallic silver (A,) formed in the silver halide emulsion layer or at the interface between the silver halide emulsion layer and a layer adjacent the silver halide emulsion layer, the nuclei being formed by the reduction of silver ions (Af). Alternatively, they may be considered as very fine particles of silver sulfide formed there by the reaction of silver ions (AJ) and a very small amount of a sulfur compound. In the former case, the iodate will suppress the formation of metallic silver by oxidizing materials which will reduce silver ions, while in the latter case the iodate compound will suppress the formation of silver sulfide by oxidizing the sulfur compound. Therefore, by incorporating the iodate compound in a photographic colloid layer of a photographic silver halide light-sensitive element the formation of the physical development nuclei will be suppressed, and the formation of yellow fogs can be reduced.

Furthermore, it has been found that by adding an unsubstituted or substituted benzenesulfinic acid, or a salt thereof, to the colloid layer, the effect of the iodate compound can be prolonged for an even longer period of time. That is, after storing a photographic silver halide light-sensitive element containing an iodate compound therein for a long period of time, or else after allowing it to stand under conditions of high temperature and high humidity, the photographic light-sensitive element can be subjected to development, fixing, and washing as usual. It will then be observed that the unexposed portions of the photographic silver halide light-sensitive element become yellowish, caused perhaps by the spontaneous decomposition of the iodate compound. However, when an unsubstituted or substituted benzenesulfinic acid or a salt thereof is incorporated in the light-sensitive element, the spontaneous decomposition of the iodate compound is suppressed, thereby further inhibiting the occurrence of yellowmg.

In other words, it is believed that the formation of yellow fogs is prevented or suppressed by an iodate compound, and the spontaneous decomposition of the iodate compound is prevented, or suppressed, by an unsubstituted or substituted benzenesulfinic compound, or a salt thereof.

In the present invention, an iodate compound, M or MIC may be employed alone, or as a mixture of two or more types of such iodate compounds. As mentioned above, if necessary, an unsubstituted or benzenesulfinic acid, or a salt thereof, may be used with the aforesaid iodate compound. In this case, the benzenesulfinic acid, or salt thereof, may be used along, or as a mixture of two or more types thereof.

There are no particular limitations with respect to the amounts of the aforesaid additives, but generally the amount of the iodate compound is preferably about 0.5 g. per kilogram of silver halide emulsion (containing about 40 g. of silver halide).

Also, in the present invention, the aforesaid additives may be effectively added in any colloid layer of a photographic silver halide light-sensitive element and also they may be added in one colloid layer or two or more colloid layers. Furthermore, the additives may be incorporated in a colloid layer at any stage, but usually it is incorporated in a colloid, such as, a silver halide emulsion, a baryta coating composition, a dispersion for use as a protective layer, etc., at the preparation thereof, together with other additives, such as hardening agents, and wetting agents.

Thus, according to the present invention, a photographic silver halide light-sensitive element capable of providing sharp images having substantially no fogs or, at worst, very few fogs, is obtained.

The invention will now be explained with reference to the following examples.

EXAMPLE 1 A baryta coating composition, containing a hardening agent, a wetting agent, etc., was applied to a paper in such proportions that the amounts of barium sulfate (anhydrous, gelatin, and sodium iodate (anhydrous) were 40 g., 4 g., and 0.05 g., respectively, per 1 square meter of the paper, to provide a baryta paper. Further, a photographic silver halide emulsion for photographic printing paper use was applied to the baryta layer thus formed to provide a photographic printing paper.

As a comparative sample, a printing paper was prepared by the same procedure as above using the baryta coating composition containing no sodium iodate.

These printing papers were stored for 6 months at a temperature of 20 C. and at a relative humidity of 70 percent. Thereafter, they were developed for 5-10 minutes at 20 C. in a developer having the following composition:

Monomethyl p-aminophenol sulfate 3 g, Sodium sulfite (anhydrous) 45 g. Hydroquinone 12 g. Sodium carbonate (anhydrous) 67.5 g. Potassium bromide 2 g.

Sodium thiosulate l 3. Water to make 3,000 ml.

The printing papers thus developed were fixed, washed and dried using standard techniques.

When the printing papers thus processed were compared as to the amount of yellow fog, the formation of yellow fog in the printing paper containing sodium iodate was much less than that in the comparative sample.

EXAMPLE 2 A silver chlorobromide emulsion containing 50 mole percent silver bromide and 0.5 g. of sodium iodate (anhydrous) per kilogram of the silver halide emulsion (containing 50 g. of silver halide), with a dye sensitize-r, an antifoggant, a hardening agent, a wetting agent, etc., was applied to a baryta-coated paper to prepare a photographic printing paper. When the printing paper thus prepared was processed as in example 1, the formation of yellow fogs was negligible.

EXAMPLE 3 A silver iodobromide emulsion containing 3 mole percent silver iodide and l g. of sodium iodate (anhydrous) per kilogram of the silver halide emulsion, together with a dye sensitizer, a hardening agent, a wetting agent, etc., was applied to a film base of triacetyl cellulose at a thickness of g./m. to provide a photographic silver halide light-sensitive film was prepared by the same procedure as above while using a silver halide emulsion having the same composition as above, with the exception that no sodium iodate was contained therein.

When the photographic light-sensitive films were processed as in example 1, yellow fogs were formed in the comparative photographic light-sensitive film, while such fogs were not formed in the photographic light-sensitive film of this invention.

EXAMPLE 4 A pure silver halide emulsion, containing 50 g. of silver chloride and 1.5 g. of sodium benzenesulfinate per kilogram of silver halide emulsion, together with a hardening agent, a wetting agent, and the like. was applied to a baryta-coated paper at a thickness of 50-80 g./m. To the emulsion layer thus formed there was applied, as a protective layer, an aqueous gelatin solution having the following composition:

Gelatin 25 g. Sodium iodate (anhydrous) l g. Saponin (6% solution) 5 ml. Water 1,000 ml.

at a thickness of 30-50 ml./m. to thereby provide a photographic printing paper. When the photographic printing paper thus prepared was processed as in example 1 after storing for a long period of time, no yellow fogs were observed.

Moreover, when the photographic printing paper and the photographic silver halide light-sensitive elements prepared in examples 1, 2 and 3 were stored at conditions of high temperature and high humidity and then processed asin example 1, yellow fogs (not as above, but yellow fogs caused by the decomposition of the iodate compound) were observed in the light-sensitive elements prepared in examples 1, 2 and 3, but no such yellow fogs were formed in the photographic printing paper which contained sodium iodate and sodium benzenesulfinate (ex. 4).

EXAMPLES 5-7 By the same procedure as in the aforesaid examples, photographic printing papers were formed, each having a light-sensitive silver halide emulsion layer containing the additive or additives shown in the following table. After processing these printing papers as in example 1, the reflection density of the yellow fogs was measured using a filter transmitting blue light having wave lengths shorter than 500 m. The results are shown in the following table.

which contained the unsubstituted or substituted benzenesulfinic acid but which contained no iodate compound, a large amount of yellow fogs were formed when they were stored for 6 months at a temperature of 20 C. and a relative humidity of 70 percent, or under high temperature and high humidity conditions.

On the other hand, when the sample of this invention of example 5 was stored for a long period of time under atmospheric conditions, the formation of yellow fogs was extremely small, when compared with the aforesaid comparative samples. In addition, when the samples of this invention of examples 6 and 7 were stored for 6 months at a temperature of 20 C. and at a relative humidity of 70 percent, or else under high temperature and high humidity conditions, a yellow fog increase was scarcely observable.

What is claimed is:

l. A photographic silver halide light-sensitive element useful in preventing yellow fog comprising a support having thereon at least one layer containing a silver halide, and one colloid layer selected from the group consisting of a photographic silver halide emulsion layer and a layer adjacent to a silver halide emulsion layer, wherein said colloid layer of said element contains:

a. a compound of the formula MlO or M10 wherein M is a hydrogen atom, an alkaline metal atom or an ammonium group, and

b. a member selected from the group consisting of unsubstituted benzenesulfinic acid, substituted benzenesulfinic acid, and salts thereof.

2. The photographic silver halide light-sensitive element as claimed in claim 1 wherein said salt of benzenesulfinic acid is sodium benzenesulfinate.

3. The photographic silver halide light-sensitive element as claimed in claim 1 wherein said salt of a substituted benzenesulfinic acid is selected from the group consisting of sodium-p-toluenesulfinate, sodium p-chlorobenzenesulfinate, and sodium p-aminobenzenesulfinate.

TABLE 1 7 Reflection density of yellow tog using blue- Sample Additive Amount Initial filter (developed for 10 minutes) (gl/cm period For 6 months at 20 For 5 days at C. C. and 70% RH and at 80% RH C t'v Ex. 1 None 0.04 0.12 0.08 iax iiigigisff 3 Ammonium iodate (anhydrous) 0.05 0. 04 0.07 0.07 Example 6 d0 05 v ,r Sodium benzenesiulfirzatcfin 0. 04 0. 04 0. 04 1 7 Potassiumperio ate an y ou Emmp e Sodium p-t0l1lellt2lS1? lfiIlB.t6 82 (3 8:

Com arative Ex. 2) Sodium bonzenes mate i. EComBarative Ex. 3) P-toluenesulfinate- 0. 10 0. 04 0. 12 0, 03

As is clear from the results shown in the table, in the com- The P P P Silver hand}? lighbsensitiv? element 9 p'arative sample hi h contained no iodate compound as a claim 1 wherein the amount of the iodate compound present [5 yellow fog preventing agent, and the comparative sample 0.5 grams per kg. of silver halide emulsion.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3977879 *Dec 20, 1974Aug 31, 1976E. I. Du Pont De Nemours And CompanyPhotographic element with contiguous layer containing an oxidizing agent
US4547452 *Sep 29, 1983Oct 15, 1985Fuji Photo Film Co., Ltd.Color diffusion transfer photographic element with sufinic acid
US4770987 *Dec 17, 1986Sep 13, 1988Fuji Photo Film Co., Ltd.Silver halide color photographic materials containing an antisain agent and a magenta coupler in lipophilic fine particles
US5443947 *Nov 30, 1993Aug 22, 1995Eastman Kodak CompanyHeat stabilized silver chloride photographic emulsions containing thiosulfonate/sulfinate compounds
US5536633 *Feb 6, 1995Jul 16, 1996Eastman Kodak CompanyHeat stabilized silver chloride photographic emulsions containing sulfur donors and sulfinate compounds
US5601970 *Jan 3, 1995Feb 11, 1997Eastman Kodak CompanyPhotographic elements exhibiting improved stability
Classifications
U.S. Classification430/608, 430/607
International ClassificationG03C1/34
Cooperative ClassificationG03C1/34
European ClassificationG03C1/34