US2995444A - Stabilization of photographic emulsions sensitized with alkylene oxide polymers - Google Patents

Stabilization of photographic emulsions sensitized with alkylene oxide polymers Download PDF

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US2995444A
US2995444A US686278A US68627857A US2995444A US 2995444 A US2995444 A US 2995444A US 686278 A US686278 A US 686278A US 68627857 A US68627857 A US 68627857A US 2995444 A US2995444 A US 2995444A
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silver
halide
alkylene oxide
oxide polymers
emulsion
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US686278A
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Dersch Fritz
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GAF Chemicals Corp
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General Aniline and Film Corp
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Priority to GB29797/58A priority patent/GB851774A/en
Priority to DEG25337A priority patent/DE1119119B/en
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
    • G03C1/34—Fog-inhibitors; Stabilisers; Agents inhibiting latent image regression
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/04—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with macromolecular additives; with layer-forming substances
    • G03C1/043—Polyalkylene oxides; Polyalkylene sulfides; Polyalkylene selenides; Polyalkylene tellurides

Definitions

  • This invention relates to photographic emulsions and in particular to light-sensitive silver-halide emulsions sensitized with alkylene oxide polymers and containing therein polyvinyl p'yrrolidone as a stabilizer and antrfogging agent.
  • photographic emulsions containing the aforementioned alkylene oxide polymers as sensitizers have a greater tendency to become fogged when compared to. photographic emulsions that are not so sensitized. This fogging tendency is particularly pronounced when photographic film, coated with a lightsensitive silver-halide emulsion containing the above described alkylene oxide polymers, is subjected to such conditions as prolonged development and storage at excessive temperatures and humidities.
  • an object of-this invention is to provide improved photographic silver-halide emulsions sensitized with alkylene oxide polymers and having low susceptibility to fogging on prolonged development and storage under conditions of high temperatures and humidities.
  • poly-N-vinyl-Z-pyrrolidone should inhibit or reduce fog is most unusual since it is known that this substance, while increasing the speed when used alone in photographic emulsion, has no efiect on reducing the fog. It would appear, therefore, that the combination of poly- N-vinyl-Z-pyrrolidone and alkylene oxide polymers co-act or operate in a synergistic manner when grouped in a photographic silver-halide emulsion, that is, the ethylene oxide polymers function as chemical sensitizers while the poly-N-vinyl-Z-pyrrolidone prevents the fogging resulting as a side effect of the sensitizers.
  • sulfur sensitizers such as porated at any convenient time during the preparation of the silver-halide emulsion, it is preferred to add it shortly before coating.
  • concentrations of poly- N-vinyl-Z-pyrrolidone ranges from 2 to 25 g. per mole of silver-halide in the emulsion; optimum concentration is about 6 g. of the stabilizer per mole of silver-halide.
  • the poly-N-vinyl-Z-pyrrolidone as used herein is a product of the General Aniline and Film Corporation and is sold under the name of PVP, type NP (nonpharmaceutical) and is available in viscosities of K-20, K-30 and K-40, all of which are suitable for use as a stabilizer in the present invention.
  • the alkylene oxide polymers are known chemical substances and many are commercially available. They can be prepared in various ways.
  • a common procedure is to react an alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide, etc., with polyhydric alcohols such as ethylene glycol, diethylene glycol, nonaethylene glycol, decaethylene glycol, dodecaethylene glycol, ring dehydration products of hexitols, etc.
  • alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide, etc.
  • polyhydric alcohols such as ethylene glycol, diethylene glycol, nonaethylene glycol, decaethylene glycol, dodecaethylene glycol, ring dehydration products of hexitols, etc.
  • the aforementioned poly-N-vinyl-2-pyrrolidone is useful for stabilizing all types of photographic silver-halide emulsions sensitized with alkylene oxide polymers.
  • alkylene oxide polymers are polyglycols and are prepared by re-' acting alkylene oxides with polyhydric alcohols, such as glycols, until the products have a molecular weight in excess of 300, preferably of 1500 or 4000 or more.
  • the resulting polyglycols can be further modified by reacting with various mono-functional etherification or ester-ification agents to introduce lipophilic groups, e.g., an aliphatic hydrocarbon chain of 8 to 18 or more carbon atoms such as n-octyl, n-dodecyl, n-tetradecyl, n-octadecyl, and the like, and a fatty acid halide of 8 to 20 carbon atoms such as noctadecoyl, n-dodecoyl, n-tetradecoyl,
  • lipophilic groups e.g., an aliphatic hydrocarbon chain of 8 to 18 or more carbon atoms such as n-octyl, n-dodecyl, n-tetradecyl, n-octadecyl, and the like, and a fatty acid halide of 8 to 20 carbon atoms such as noct
  • polyalkylene oxide polymers as stabilizers and poly-N-vinyl-Z-pyrrolidone as an antifoggant for photographic silver-halide emulsions are effectual in the presence or absence of optical sensitizing dyes, color formers, or other addenda commonly incorporated in photographic emulsions.
  • My invention is not limited to silver-halide emulsions wherein the carrier is gelatin but may be incorporated with other light-sensitive materials wherein the carrier can be polyvinyl alcohol, casein, carboxy methyl cellulose, and the like-
  • the carrier can be polyvinyl alcohol, casein, carboxy methyl cellulose, and the like-
  • the invention is illustrated in greater detail but not limited or restricted by the following example.
  • a silver-halide emulsion in gelatin containing 4% silver iodide and 96% silver bromide was prepared in a conventional manner and brought up to its maximum light sensitivity. It was then readied for coating, finals were added such as sensitizing dyes, stabilizers and hardeners.
  • a 25% aqueous solution of PVP (NP: K-30) was prepared and added to the emulsion.
  • the emulsion samples contained about 0.4 mole of silver-halide. The so prepared emulsion samples were coated on a suitable cellulose ester base and dried.
  • a photographic element comprising a support, at least one light-sensitive silver-halide emulsion layer comprising a silver-halide dispersed in a colloidal carrier selected from the class consisting of gelatin, polyvinyl alcohol, casein, and carboxy methyl cellulose, said emulsion layer containing in intimate contact with the silver halide grains thereof, a sensitizing quantity of an alkylene oxide polymer having a molecular weight of at least 300 and being selected from the group consisting of a polyalkylene glycol, a polyalkylene glycol ether wherein the ether group is an aliphatic chain of from 8 to 18 carbon atoms and a polyalkylene glycol ester wherein the ester group is an aliphatic chain of from 8 to 18 carbon atoms and as' an antifogging agent for said emulsion layer and in intimate contact with the silver halide. grains thereof 2 g. to g. per mole of silver-halide in the emulsion of poly-N

Description

polymers.
United States Patent Ofiice 2,995,444 Patented Aug. 8, 1961 STABILIZATION F PHOTOGRAPHIC' EMUISIONS SENSITIZED WITH ALKYLENE OXIDE POLY- MERS Fritz Derseh, Blnghamton, N.Y., assiguor to General Aniline & Film Corporation, New York, N.Y., a corporation of Delaware No Drawing. I Filed Sept. 26, 1957, Ser. No. 686,278
3 Claims. Cl 96-107) This invention relates to photographic emulsions and in particular to light-sensitive silver-halide emulsions sensitized with alkylene oxide polymers and containing therein polyvinyl p'yrrolidone as a stabilizer and antrfogging agent.
It is known that the sensitivity of photographic emulsions, i.e., light-sensitive gelatino silver-halide emulsions can be increased by incorporating in said emulsions various alkylene oxide polymers which act in a manner analogous to the allylthioureas, thiocyanates, sodium thiosulfate, sodium hyposulfite, and the like, and in this connection reference is made to US. Patents 2,400,532, 2,441,389 and 2,423,549.
It is likewise known that photographic emulsions containing the aforementioned alkylene oxide polymers as sensitizers have a greater tendency to become fogged when compared to. photographic emulsions that are not so sensitized. This fogging tendency is particularly pronounced when photographic film, coated with a lightsensitive silver-halide emulsion containing the above described alkylene oxide polymers, is subjected to such conditions as prolonged development and storage at excessive temperatures and humidities. It, therefore, becomes necessary to employ rather large quantities of antifoggants in order to overcome the greater susceptibility to fogging of photographic emulsions sensitized with the alkylene oxide However, this remedy of using excessively high amounts of an 'foggants partly ofisets the speed advantage gained from the alkylene oxide polymers in the first place with the result that the net increase in sensitivity of such photographic emulsions is very slight.
It is accordingly an object of this invention to provide photographic emulsions with increased sensitivity.
Specifically, an object of-this invention is to provide improved photographic silver-halide emulsions sensitized with alkylene oxide polymers and having low susceptibility to fogging on prolonged development and storage under conditions of high temperatures and humidities.
Other objects will appear hereinafter as the description proceeds.
The foregoing objects are attained by bringing poly-N- vinyl-2-pyrrolidone into operative association with the photographicemulsions stabilized with alkylene oxide polymers. The resulting emulsions possess the higher sensitivity of emulsions containing the alkylene oxide polymers but without their high fogging tendencies.
That poly-N-vinyl-Z-pyrrolidone should inhibit or reduce fog is most unusual since it is known that this substance, while increasing the speed when used alone in photographic emulsion, has no efiect on reducing the fog. It would appear, therefore, that the combination of poly- N-vinyl-Z-pyrrolidone and alkylene oxide polymers co-act or operate in a synergistic manner when grouped in a photographic silver-halide emulsion, that is, the ethylene oxide polymers function as chemical sensitizers while the poly-N-vinyl-Z-pyrrolidone prevents the fogging resulting as a side effect of the sensitizers.
It is to be understood, however, that the above explanation is merely offered as a theory to explain the mode of operation of this invention and is not to be construed as imposing a limitation or narrowing thereof.
so-called sulfur sensitizers such as porated at any convenient time during the preparation of the silver-halide emulsion, it is preferred to add it shortly before coating. Themost useful concentrations of poly- N-vinyl-Z-pyrrolidone ranges from 2 to 25 g. per mole of silver-halide in the emulsion; optimum concentration is about 6 g. of the stabilizer per mole of silver-halide.
The poly-N-vinyl-Z-pyrrolidone as used herein is a product of the General Aniline and Film Corporation and is sold under the name of PVP, type NP (nonpharmaceutical) and is available in viscosities of K-20, K-30 and K-40, all of which are suitable for use as a stabilizer in the present invention. The letter K represents a function of the mean molecular weight of the compound and is derived from the Fikentscher formula wherein c is the concentration in g./- ml. of solution, a is the viscosity of the solution compared to the solvent and K=1000K The alkylene oxide polymers are known chemical substances and many are commercially available. They can be prepared in various ways. For instance, a common procedure is to react an alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide, etc., with polyhydric alcohols such as ethylene glycol, diethylene glycol, nonaethylene glycol, decaethylene glycol, dodecaethylene glycol, ring dehydration products of hexitols, etc. For additional information on the preparation of the above substances, reference is'made to The Chemistry of Synthetio Resins, pages 990-994, published by Reinhold Publishing Corporation (1935).
In general, the aforementioned poly-N-vinyl-2-pyrrolidone is useful for stabilizing all types of photographic silver-halide emulsions sensitized with alkylene oxide polymers. However, it has been found that superior results ensue when my stabilizer is incorporated in emulsions sensitized with alkylene oxide polymers of the class described in the previously cited patents. These alkylene oxide polymers are polyglycols and are prepared by re-' acting alkylene oxides with polyhydric alcohols, such as glycols, until the products have a molecular weight in excess of 300, preferably of 1500 or 4000 or more. The resulting polyglycols can be further modified by reacting with various mono-functional etherification or ester-ification agents to introduce lipophilic groups, e.g., an aliphatic hydrocarbon chain of 8 to 18 or more carbon atoms such as n-octyl, n-dodecyl, n-tetradecyl, n-octadecyl, and the like, and a fatty acid halide of 8 to 20 carbon atoms such as noctadecoyl, n-dodecoyl, n-tetradecoyl,
of aqueous salts usually by washing, (3) the second diges-.
tion or after-ripening to obtain increased sensitivity.
The combination of polyalkylene oxide polymers as stabilizers and poly-N-vinyl-Z-pyrrolidone as an antifoggant for photographic silver-halide emulsions are effectual in the presence or absence of optical sensitizing dyes, color formers, or other addenda commonly incorporated in photographic emulsions.
My invention is not limited to silver-halide emulsions wherein the carrier is gelatin but may be incorporated with other light-sensitive materials wherein the carrier can be polyvinyl alcohol, casein, carboxy methyl cellulose, and the like- The invention is illustrated in greater detail but not limited or restricted by the following example.
A silver-halide emulsion in gelatin containing 4% silver iodide and 96% silver bromide was prepared in a conventional manner and brought up to its maximum light sensitivity. It was then readied for coating, finals were added such as sensitizing dyes, stabilizers and hardeners. A 10% solution of polyethylene oxide lauryl ether (a product sold by the Atlas Powder Company, Wilmington, Delaware, under the trade name BRII 35") in water was prepared and added to the emulsion. Also, a 25% aqueous solution of PVP (NP: K-30) was prepared and added to the emulsion. The emulsion samples contained about 0.4 mole of silver-halide. The so prepared emulsion samples were coated on a suitable cellulose ester base and dried. Samples of these film coatings were then ex- 35 is in I 5:3 if the 321 223mm. deYeloped m a References Cited in the file of this patent G, UNITED STATES PATENTS 1.5 2,423,549 Blake et aL my 1947 Mum wlfits, anhydrous 45 4; 2,495,918 301 1m 31, .1950 mm biwlfifi 1 2,712,995 Weyde My 12, 1955, Hydroquinone 3 Sodium carbonate, monohydrated. 6 FOREIGN PATENTS Potassium bromide 8 687,751 Great Britain Feb. 18, 1953 Water to make 1 liter.
I claim:
-1. A photographic element comprising a support, at least one light-sensitive silver-halide emulsion layer comprising a silver-halide dispersed in a colloidal carrier selected from the class consisting of gelatin, polyvinyl alcohol, casein, and carboxy methyl cellulose, said emulsion layer containing in intimate contact with the silver halide grains thereof, a sensitizing quantity of an alkylene oxide polymer having a molecular weight of at least 300 and being selected from the group consisting of a polyalkylene glycol, a polyalkylene glycol ether wherein the ether group is an aliphatic chain of from 8 to 18 carbon atoms and a polyalkylene glycol ester wherein the ester group is an aliphatic chain of from 8 to 18 carbon atoms and as' an antifogging agent for said emulsion layer and in intimate contact with the silver halide. grains thereof 2 g. to g. per mole of silver-halide in the emulsion of poly-N-vinyl-Z-pyrrolidone having a K-value of from in the colloidal carrier for the light-sensitive silver-halide

Claims (1)

1. A PHOTOGRAPHIC ELEMENT COMPRISING A SUPPORT, AT LEAST ONE LIGHT-SENSITIVE SILVER-HALIDE EMULSION LAYER COMPRISING A SILVER-HALIDE DISPERSED IN A COLLOIDAL CARRIER SELECTED FROM THE CLASS CONSISTING OF GELATIN, POLYVINYL ALCOHOL, CASEIN, AND CARBOXY METHYL CELLULOSE, SAID EMULSION LAYER CONTAINING IN INTIMATE CONTACT WITH THE SILVER HALIDE GRAINS THEREOF, A SENSITIZING QUANTITY OF AN ALKYLENE OXIDE POLYMER HAVING A MOLECULAR WEIGHT OF AT LEAST 300 AND BEING SELECTED FROM THE GROUP CONSISTING OF A POLYALKYLENE GLYCOL, A POLYALKYLENE GLYCOL ETHER WHEREIN THE ETHER GROUP IS AN ALIPHATIC CHAIN OF FROM 8 TO 18 CARBON ATOMS AND A POLYALKYLENE GLYCOL ESTER WHEREIN THE ESTER GROUP IS AN ALIPHATIC CHAIN OF FROM 8 TO 18 CARBON ATOMS AND AS AN ANTIFOGGING AGENT FOR SAID EMULSION LAYER AND IN INTIMATE CONTACT WITH THE SILVER HALIDE GRAINS THEREOF 2G. TO 25G. PER MOLE OF SILVER-HALIDE IN THE EMULSION OF POLY-N-VINYL-2-PYRROLIDONE HAVING A K-VALUE OF FROM K-20 TO K-40.
US686278A 1957-09-26 1957-09-26 Stabilization of photographic emulsions sensitized with alkylene oxide polymers Expired - Lifetime US2995444A (en)

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US686278A US2995444A (en) 1957-09-26 1957-09-26 Stabilization of photographic emulsions sensitized with alkylene oxide polymers
GB29797/58A GB851774A (en) 1957-09-26 1958-09-17 Stabilization of photographic emulsions sensitized with alkylene oxide polymers
DEG25337A DE1119119B (en) 1957-09-26 1958-09-19 Photographic material with photosensitive halide silver emulsion layer and polyalkylene oxide content

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3058826A (en) * 1959-12-11 1962-10-16 Du Pont Photographic elements exhibiting reduced haze and method for preparation
US3173790A (en) * 1962-09-19 1965-03-16 Gen Aniline & Film Corp Silver halide emusions containing polyoxyalkylene sensitizers
US3516830A (en) * 1965-09-17 1970-06-23 Eastman Kodak Co Photographic silver halide emulsions and elements
US3549375A (en) * 1967-05-08 1970-12-22 Gaf Corp Antistatic photographic film

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE612311A (en) * 1962-01-05
US3276875A (en) * 1963-12-02 1966-10-04 Du Pont Developing composition with pyrrolidone anti-sludging agent
GB1194334A (en) * 1966-09-19 1970-06-10 Agfa Gevaert Nv Developing Direct-Positive Silver Halide Photographic Materials
DD127586A1 (en) * 1976-09-16 1977-10-05
US5550013A (en) * 1994-12-22 1996-08-27 Eastman Kodak Company High chloride emulsions having high sensitivity and low fog and improved photographic responses of HIRF, higher gamma, and shoulder density

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2423549A (en) * 1945-01-10 1947-07-08 Du Pont Silver halide photographic emulsions sensitized by polyalkylene glycols
US2495918A (en) * 1948-08-28 1950-01-31 Du Pont Poly-n-vinyl lactam photographic silver halide emulsions
GB687751A (en) * 1950-01-13 1953-02-18 Bayer Ag Process and material for the direct production of positive photographic images
US2712995A (en) * 1949-07-04 1955-07-12 Agfa Ag Process for the direct production of positive photographic images

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE881445C (en) * 1944-08-08 1953-06-29 Agfa Ag Fuer Photofabrikation Process for the prevention of yellow haze in photographic materials
BE537789A (en) * 1952-11-08
BE530063A (en) * 1953-07-01
BE537787A (en) * 1954-04-29
US2704716A (en) * 1954-06-17 1955-03-22 Eastman Kodak Co Melonate and cyamelurate stabilizers for photographic emulsions sensitized with alkylene oxide polymers

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2423549A (en) * 1945-01-10 1947-07-08 Du Pont Silver halide photographic emulsions sensitized by polyalkylene glycols
US2495918A (en) * 1948-08-28 1950-01-31 Du Pont Poly-n-vinyl lactam photographic silver halide emulsions
US2712995A (en) * 1949-07-04 1955-07-12 Agfa Ag Process for the direct production of positive photographic images
GB687751A (en) * 1950-01-13 1953-02-18 Bayer Ag Process and material for the direct production of positive photographic images

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3058826A (en) * 1959-12-11 1962-10-16 Du Pont Photographic elements exhibiting reduced haze and method for preparation
US3173790A (en) * 1962-09-19 1965-03-16 Gen Aniline & Film Corp Silver halide emusions containing polyoxyalkylene sensitizers
US3516830A (en) * 1965-09-17 1970-06-23 Eastman Kodak Co Photographic silver halide emulsions and elements
US3549375A (en) * 1967-05-08 1970-12-22 Gaf Corp Antistatic photographic film

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DE1119119B (en) 1961-12-07
GB851774A (en) 1960-10-19

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