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Publication numberUS2057764 A
Publication typeGrant
Publication dateOct 20, 1936
Filing dateJul 19, 1934
Priority dateJul 22, 1933
Publication numberUS 2057764 A, US 2057764A, US-A-2057764, US2057764 A, US2057764A
InventorsBrunken Johannes
Original AssigneeAgfa Ansco Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Manufacture of stabilized silver halide emulsions
US 2057764 A
Abstract  available in
Images(3)
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Claims  available in
Description  (OCR text may contain errors)

Patented Oct. 20, 1936 UNITED STATES PATENT OFFICE MANUFACTURE OF STABILIZED SILVER HALIDE EMULSIONS No Drawing. Application July 19, 1934, Serial 16 Claims.

My present invention relates to stabilizing 10 on a photographic silver halide emulsion which may be unsensitized or which has been sensitized or hyper-sensitized increases the stability of this emulsion.

As compared with the known stabilizers the sull phinates and the selninates have the advantage of not affecting thephotographic properties of the emulsion, for example the sensitivity and gradation.

For the purpose of the invention there may be 20 used an alkali salt or another soluble salt of an aliphatic or aromatic or hydroaromatic or heterocyclic sulphinicor seleninic-acid, for instance, such a salt of methane-sulphinic acid, methane disulphinic acid, methane-trisulphinic acid, 25 ethane-sulphinic acid, ethane disulphinic acid, benzene-sulphinic acid, a chlorobenzene-sulphinic acid, toluene-para-sulphinic acid, anisol-parasulphinic acid, acetanilide-para-sulphinic acid, salicylic-sulphinic acid, benzene-meta-disulphinic o acid, naphthalene-p-sulphinic acid, cyclohexylsulphinic acid, thiophene-sulphinie acid, benzeneseleninic acid, methane-seleninic acid, ethaneseleninic acid.

Instead of the salts, the free acids likewise may 35 be used. However, if the quantity used is too large, a loss of sensitivity occurs as a consequence of the reduction of the pH-value. Therefore, the stabilizer is preferably added in the form of a salt. The amount of stabilizer added to 1 kg. of wet at, emulsion generally varies from 0.5 to 5 grams.

However, the invention is not limited to these quantities; the most suitable amount of stabilizer to be used can be easily determined by experi- 50 is used a liquid in which the stabilizer is soluble i a and which does not affect the emulsion. Preferably there is used water or an organic solvent which is miscible with water, for instance, alcohol. I have furthermore found, that the fogging infiuence of supports, preparation layers, backing benzene-seleninic acid in 25 cc. of water.

In Germany July 22, 1933 layers, intermediate layers, sub-layers, protective layers, or baryta-layers can be prevented by incorporating in these layers the salt of a sulphinic or seleninic acid. For instance, an anti-halation layer of glassmakers soap often causes fogging 5 of the silver halide. emulsion layer to which it is attached, so that such photographic materials have a poor stability. Furthermore the paper used for finishing or packing photographic materials causes the emulsion to be fogged and thus shortens the life of the photographic material. The fogging action of the aforesaid materials can be considerably reduced by the incorporation of a salt of a sulphinic acid or a seleninic acid.

The following examples serve to illustrate the invention.

Example 1.l kilo of a wet gelatino silver halide emulsion containing 6 to 7 per cent of silver halide and 8.5 per cent of gelatin is molten in the usualway and mixed with a solution of 3 grams of the sodium salt of benzene-sulphinic acid in cc. of Water. The emulsion is then cast on a film base and made partly into a roll film and partly into a film pack. These films and films made with the same silver halide emulsion, but without 25 the addition of the sodium salt of benzene-sulphinic acid, showed when freshly prepared the same sensitivity and the same fog of 0.12 density unit. After storing the roll film in a drying stove heated to 50 C. for two weeks the film showed a fog of:

Density unit Film without addition 0.43 Film with the sodium salt of benzene-sulphinic acid- 0.25

After storing the film packs in a drying stove heated to 50 C. for three weeks, the films showed a fog:

Density unit Film without addition 0.55to0.60 Film containing the sodium salt of benzene-sulphinic acid 0.25 to 0.28

Similar results are obtained when the sodium salt of benzene sulfinic acid is replaced'by the sodium salt of ethane sulfinicacid, a chlorobenzene-sulfinic acid, toluene-para-sulfinic acid, or naphthalene-sulfinic acid,

Ewamplc 2:1 kilo of an unsensitized wet emulsion containing 9 per cent of gelatin and 6 to 7 per cent of silver halide is molten and mixed with a solution of 1 gram of the sodium salt of The emulsion is then cast on glass plates. In freshly prepared condition the plates made from the Density unit Emulsion without addition 0.43 Emulsion containing the sodium salt of benzene-seleninic acid -1 0.21

Example 3:-An Agfa-Isochrome" plate (registered trade-mark) is bathed for 10 minutes in the following solution:

Water liter" 1 Crystalline sodium carbonate grams 5 Concentrated ammonia solution cc 5 Sodium salt of hexahydrobenzene-sulfinic a i grams 10 After having been thoroughly rinsed the plate is dried in a current of warm air. The plate is stored in a drying stove heated to C. for three days together with a plate of the same brand of emulsion which has not been bathed. After this treatment the plates showed a fog:

Density unit Plate containing the sodium salt of hexahydrobenzene-sulflnic acid 1.3

Example 4.'To 1 kilo of an emulsion of glassmakers soap in gelatin containing about 8 per cent of gelatin there is added a solution of 5 grams of the sodium salt of ethane-suifinic acid in 25 cc. of water, and the emulsion is cast on a support to form an anti-halation layer. On the dry anti-halation layer there is cast a photographic emulsion containing 6 to 7 per cent of silver halide and 8.5 per cent of gelatin and sensitized with 1.1'-diethyl-6-methyl-benzthiopseudocyanine iodide or 1.1'-diethyl-benzselenopseudocyanine perchlorate. (The emulsion contains about 15 m r. of sensitizer in 1 kilo of wet emulsion.) The photographic material thus made was stored in a drying stove heated to 50 C. to-

gether with photographic material made in the same manner but without the addition of the sodium salt of ethane-suifinic acid. After 9 days storing the materials showed a fog:

Density unit Material without addition 0.94

Material with addition of the sodium salt of 1 ethane suifinic acid. 0.48

Example 5:Black-red paper such as is used in winding roll films is bathed for 10 minutes in a 10 per cent solution of the sodium salt of thiophene-sulflnic acid in methanol of 50 per cent strength. This paper, as well as paper which has been treated with methanol of 50 per cent strength without addition and paper which has not been treated at all were placed in contact with the emulsion side of a photographic film in a drying stove heated to 50 C. The film showed a fog of 0.08 density unit before beginning the test. After a 9 days storing the films showed a fog:

The test in the above examples was performed by developing the photographic emulsion tor 5 minutes'in a developer of the-following com position:

Water was- -1 Para-methylaminophenol sulfate -grams-.. 1.5 Hydroquinone -do 2.5 Potassium carbonate do 18.0 Potassium bromide do---.. 1.0 Sodium suliite sicc -do 18.0

The film was then fixed, and after drying the density was determined in the Martens densitometer.

In the examples gelatin is used as a binding agent for the emulsion, however, the stabilizing eflect of the described stabilizers is not limited to emulsions prepared with this binding agent, but there may be used also other binding agents, for instance, collodium, agar-agar, casein, albumen, and polyglucuronic acid.

As above described the stabilizer may be added to the emulsion at any stage of its production, but it may also be added already to the parent material for making the emulsions. When the stabilizing agent is to be added to the support to which the emulsion is attached, it is preferably added before the support is cast. To a preparation layer, an intermediate layer, a backing, a sub-layer or a protective layer the stabilizer is added shortly before casting these layers. In the case of paper it is preferably added to the paper pulp. In the case of paper coated with gelatin and barium sulfate it is added to the casting solution from which the layer is made.

What I claim is:

1. A method of preventing a silver halide emulsion from becoming fogged which comprises bring the emulsion in contact with a soluble compound selected from the group consisting of a sultlnic acid, a seleninic acid and their salts.

2. A method of preventing a silver halide emulsion from becoming fogged which comprises bringing the emulsion in contact with a soluble salt of an acid selected from the group consisting of a suifinic acid and a seleninic acid.

3. A method of preventing a silver halide emulsion from becoming fogged which comprises bringing the emulsion in contact with an alkali salt of an acid selected from the group consisting of a suifinic acid and a seleninic acid.

4. A method of preventing a silver halide emulsion from becoming fogged which comprises incorporating in a layer which is in contact with the emulsion layer a soluble salt of an'acid selected from the group consisting of suifinic acid and seleninic acid.

5. A method of preventing a silver halide emulsion from becoming fogged which comprises incorporating in the emulsion a soluble salt of an acid selected from the group consisting of sulfinic acid and seleninic acid.

6. A method of preventing a silver halide emulsion from becoming fogged which comprises adding to a wet and molten gelatino silver halide emulsion sodium salt of benzene-suifinic acid dissolved in 25 cc. of water and casting the photographic material from this emulsion.

7. A method of preventing a silver halide emulsion from becoming fogged which comprises adding to a wet emulsion of gelatin and glassmakers soap sodium salt of ethane-sulfinic acid dissolved in 25 cc. of water, casting the emulsion on a support to form an anti-halation layer, drying this layer, and casting on this layer a gelatino silver halide emulsion containing a sensitizer.v

8. A method or preventing a silver halide emulsion irom becoming logged which comprises adding to a wet gelatino silver halide emulsion so dium salt of benzene-seleninic acid dissolved.- in 25 cc. of water and casting the emulsion from this solution.

9.- A photographic material comprising a silver halide gelatin emulsion in contact with a soluble compound selected from the group consisting of a sulflnic acid, a seleninic acid and their salts.

10. A photographic material comprising a silver halide emulsion in contact with a soluble salt of an acid selected 'from the group consisting of a sulflnic acid and a seleninic acid.

11. A photographic material comprising a silver halide emulsion in contact with an alkali salt of an acid selected from the group consisting of a sulflnic acid and a seleninic acid.

12. A photographic material comprising a silver halide emulsion containing as an addition a soluble salt of an acid selected from the group consisting of a sulflnic acid and a seleninic acid.

13. A photographic material comprising a gelatino silver halide emulsion in contact with a layer containing a soluble salt of an acid selected from the group consisting of a sulflnic acid and a seleninic acid.

14. A photographic material comprising a silver halide emulsion containing the sodium salt of benzene-sulflnic acid.

15. A photographic material comprising a gelatino silver halide emulsion containing the sodium salt of benzene-seleninic acid.

' 16. A photographic material comprising a support, attached to said support an anti-halation layer comprising gelatin as a binding agent and having incorporated glassmakers soap and the sodium salt of ethane-disulflnic acid, and attached to this anti-halation layer a gelatino silver halide emulsion layer containing a sensitizer.

JOHANNES BRUNKEN.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2432864 *Jan 18, 1945Dec 16, 1947Ilford LtdPhotographic elements bearing silver halide emulsion layer and adjacent light-insensitive colloid layer containing silver derivatives of azoles
US2438716 *Oct 6, 1944Mar 30, 1948Gen Aniline & Film CorpStabilized silver halide emulsions
US2440110 *Oct 6, 1944Apr 20, 1948Gen Aniline & Film CorpStabilized silver halide emulsions
US2440206 *Sep 16, 1944Apr 20, 1948Gen Aniline & Film CorpStabilized silver halide emulsions
US3088824 *Feb 17, 1959May 7, 1963Cons Electrodynamics CorpRapid photographic developing
US3144336 *Oct 26, 1961Aug 11, 1964Eastman Kodak CoSynergistic sensitization of photographic silver halide emulsions
US3466173 *Nov 29, 1966Sep 9, 1969Keuffel & Esser CoSilver halide element containing a developer and aromatic sulfinic acid stabilizers
US3728126 *Mar 6, 1970Apr 17, 1973Agfa Gevaert NvSilver halide emulsion containing an organic selenium compound antifogging agent
US4125403 *Jun 27, 1977Nov 14, 1978Fuji Photo Film Co., Ltd.Heat developable light sensitive material
US4547452 *Sep 29, 1983Oct 15, 1985Fuji Photo Film Co., Ltd.Color diffusion transfer photographic element with sufinic acid
US5110719 *Nov 13, 1990May 5, 1992Fuji Photo Film Co., Ltd.Reduction of minimum image density without reduction of maximum image density
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 CompanyContaining thiophosphate ester
DE1020864B *Apr 28, 1956Dec 12, 1957Gevaert Photo Prod NvVerfahren zur Herstellung von lichtempfindlichen photographischen Emulsionen
EP0358170A2 *Sep 5, 1989Mar 14, 1990Fuji Photo Film Co., Ltd.Direct positive photographic materials
Classifications
U.S. Classification430/510, 430/959, 430/607
International ClassificationG03C1/34
Cooperative ClassificationG03C1/346, Y10S430/16
European ClassificationG03C1/34S