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US2284877A - Light sensitive color element - Google Patents

Light sensitive color element Download PDF

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Publication number
US2284877A
US2284877A US394663A US39466341A US2284877A US 2284877 A US2284877 A US 2284877A US 394663 A US394663 A US 394663A US 39466341 A US39466341 A US 39466341A US 2284877 A US2284877 A US 2284877A
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United States
Prior art keywords
color
resin
solution
emulsion
layer
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Expired - Lifetime
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US394663A
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English (en)
Inventor
Martinez Michele
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Eastman Kodak Co
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Eastman Kodak Co
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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
    • G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
    • G03C7/30—Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials
    • G03C7/388—Processes for the incorporation in the emulsion of substances liberating photographically active agents or colour-coupling substances; Solvents therefor

Definitions

  • This invention relates to color photography and particularly to sensitive photographic elements having color forming components incorporated therein. Many processes have been proposed for recording different color aspects in a photographic element for the purpose of producing natural color photographic records.
  • An object of the present invention is to provide an improved method for the formation of colbred photographic images.
  • Afurther object is to provide a method forthe formation of colored photographic images by means of dye components or color formers rendered insoluble in sensitive photographic layers.
  • the present invention differs from that of my prior application in what I call insulation of the sensitive grains.
  • the individual photochemical properties of each of the differently sensitized grains are preserved with the possibility of singling out any group of light elements for treatment without acting on the others.
  • This method differs from similar salts orcompounds may be made to be that of my prior application in that the color- I forming means and the sensitive agent are contained in' a single grain whereas in the method of my prior application the color forming means was localized in the emulsion containing the sensitivesalt.
  • the accompanying drawing illustrates in section View a photographic element formed accordtion:
  • the object by precipitating si e'halid in the presence of aisynthetic or,jnaturalvresin gdm orgum-resin, 55 including also mixtures of resins with rubber present invention is achieved or similar substance, preferably of water-repellent properties, in such a way that the silver salt is formed within or in close physical association with the resin, which is the insulator of' the grain so formed:
  • adjuncts such as coloring matters, other metal salts, color sensitizers, color formers and also present at the time of precipitation, so that they too form part of the grain: in certain cases, specially if soluble ,in alcohol or other volatile solvent, some adjuncts may be admixed soon after precipitation with the result that they also come to be closely associated with, or superimposed to, the grain.
  • Natural resins available may be colored and colorless. Colored ones may be usefully employed for layers and grains in which a light
  • a variety-of solvents are available, such as ethyLamyl arid methyl'alcohols, acetone, ether, benzene, chloroform, petroleum spirits, turpentine and other oils, amyl acetate, xylene, ethyl acetate, carbon disulphide, and even acetic acid.
  • Such resins may be condensation products of formaldehyde or phenol alcohols with phenols, oxy-, aryloxy or alkyloxy-carboxylic' acidsor phenoxy fatty I acids; also such synthetic resins as mayfurther be treated with halogen fatty acids or the condensation products of phenols or phenol carboxylic acids with aliphatic, aromatic or heterocyclic aldehydes or thionyl chloride; polyvinyl esters or acetals, polyvinyl alcohol blended with polybasic acids, alkyd resins, polystyrene resins;
  • latex and synthetic rubbers such as polymerised butandiene and polymerised chlorobutandiene,
  • insulated light sensitive elements all of which more or less include known procedure by which light sensitive salts are formed.
  • the insulated elements may be produced all alike of a type, or of difierent types. Grains of a type may be used to produce uniform layers for general or particular purposes. Layers each of a uniform type, but the type varying in each layer, may be used in multilayer materials, in biand tri-packs, and in sets of materials for color photography by superimposition of separate records. Different types of grains can be mixed to form a layer of the mixed grain type.
  • differentiating adjuncts mean to indicate the par ticular agents, such as color formers, metal salts, sensitisers and coloring matters which are required to obtain that any particular type of grain be impressed predominantly by colored rays which do not so impress other types of grains and to obtain that it be capable of-being processed to yield an image of a color different from the color that other types of grain can be made to produce, so that these two characteristics of each grain may be utilised to serve the purposes of color photography.
  • resins are the only medium employed.
  • Two separate alcoholic solutions are made, one of an alcohol-soluble halide, such as chloride or bromide of ammonium, lithium, zinc, strontium, calcium, gold barium, the other of silver nitrate in equivalent quantity by specific weight.
  • a quantity of resin equal for instance to about from one to three grams for every five I grams of silver nitrate.
  • Citric, tartaric or phosphoric acid and other adjuncts generally employed in the making of cellulosic and collodion emulsions may be employed in either solution, and the customary known manner of mixing, temperature, and the like observed.
  • a color former may be incorporated, for instance from gr.
  • Color sensitisers, coloring matters, and the like may also be added at the time of mixing or afterwards, and also such plasticizers as may be desired, such as castor oil, glycerine, amyl acetate, triacetin, tricresyl phosphate and the like.
  • Uniform layers of this type can be made also by coating on a support first a solution of an halide and resin in volatile solvent or in alkali and then applying over it a solution of silver nitrate, which may then be in water and may contain an acid, preferably organic, to destroy any alkalinity present Adjuncts, as specified, in either solution.
  • a mixed grain emulsion of the same type may be made by forming two or three separate emulsions in the same way, with resins of different solubility; each emulsion containing a resin in a. solvent in which the other or others are not soluble or are sparingly soluble.
  • Silver nitrate may not then be soluble in the solvent required by the resin, but alcohol can always be added to other volatile solvents, thus silver nitrate would in such cases be dissolved in alcohol and added to the solution of the resin in its proper solvent.
  • one lot of emulsion may be made with benzoin or shellac in alcohol or with dragon's blood in ethyl acetate, a second lot with sandarac in acetone, and a third with mastic or dammar in benzene.
  • diiferentiating adjuncts can be added, as previously explained.
  • Xylene can also be used as one of the solvents.
  • Uniform single layers can be made in sets, on such supports as regenerated cellulose and thin Celluloid, for three-color photography by superimposition of separate color records: after the latter have been processed, dried, and assembled in register they can be made to permanently adhere to each other simply by application of controlled heat, the resins in the layers acting as adhesive.
  • alcohol-soluble halides may be employed with a resin in appropriate solvent as one of the solution, while silver nitrate and gelatin would then be in the other solution, preferably, in this case, with addition of ammonia g. s. in the silver-gelatin solution: the latter may also be divided in two lots, one with. and the other without ammonia, to produce an emulsion of a determined degree of contrast: or else the silver nitrate only maybe in two lots: one present in the gelatin, the other added to it after addition of the halides and resin solution.
  • Mixed grain emulsions are formed out of two or three lots of emulsions, each of which must then contain at least one differentiating adjunct, preferablyadded to one of the main solutions before precipitation of the sensitive salt. It is an essential point that the various lots of emulsions that are to be used to make a mixed grain vents, or by substituting a solution of the desired medium for the gelatin in any of the other described forms, mutatis mutandis.
  • the grains ob--- tained are washed and, if desired, dried. They may be emulsified or dispersed afterwards in any suitable colloid or other binding medium, in-
  • cluding Celluloid regenerated cellulose and the like.
  • Suitable additions may be made to any of the solutions before precipitation, or to the water in which the latter occurs, or to the binding medium in whichthe precipitates are afterwards suspended dispersed or emulsified. 5.
  • Emulsions in collodion or celloidine or other cellulosic product, or in a solution of another resin may be'cbtained'by adding a suitable solution ofany of these substances to either. or both of two main part solutions made in suitable solof volatile solvents.
  • other water soluble resinate may then be used, for instance, together witha solutionv of halide salts, so as to produce with silver salt or/and other metal salt at the same time silver halide and insoluble metal resinate closely associated one with the other.
  • an alkaline solution. of a resin may be employed on the one hand, and silver with an acid, preferably organic, on the other handi or else an acid is added soon after precipitation, so as to reconstitute the resin. Suitable adjuncts always as desired.
  • the various insulated elements that are produced in gelatin or mixed in gelatin may not be of the same type or struck, so to speak, on the same kind of resin: the resins may be different for each type, so as to constitute themselves another differentiating adjunct: for instance they may be of different resistance to alkaline sion in color photography is to provide means for recording and reproducing images of at leasttwo different colors in the established laws of the art, which are thus to be followed.
  • the insulated elements present in a mixed grain layer at least two should be reciprocably sensitive to rays of complementary colors.
  • Materials bearing in a single layer or in two or three layers at least two grains of differentiated properties may be made topreproduce in direct or reversai treatments images in the same colors as that of the rays affecting them or colors complementary to them or in any other given color desired.
  • the mixed grains should also be in certain quantity relatively to each other. For instance, in a material intended for use by daylight there should be more grains sensitive to 'red rays than grains sensitive to blue-violet rays, I
  • Grains for'two or three colors may be in a layer that may be placed over another layer of plain ordinary emulsionintendd to produce, for instance, a thin black image to be left black, or another color.
  • grains for one or two colors may be mixed with plain emulsion of the usual kind intended for black image or for an image in a second or third color: in such cases Sodium .or potassium. or
  • the processing should be such as to produce a color or colors in the grains and another in the interstices between them, that is in the plain emulsion between them, which, of course, may be appropriately sensitised and contain also a color former and the like or be associated with a salt of a metal other than silver.
  • a two-layer material carrying in each layer a grain in a plain emulsion, so as to produce three colors and a black record, may constitute a successful embodiment of this invention.
  • a compensating light filter such as may be eliminated afterwards in treatments, may be either incorporated in the gelatin or plain emulsion in which the insulated elements of this invention are suspended, or may be coated in suitable layer over them.
  • the insulated color elements preferably embody an adjunct for independent color'formation, that is a means by which each element of a type may be made to produce a color independently from that which may be produced by other elements of another type or in surrounding plain emulsion in which they may be embedded.
  • Such means may be one or more of the following: i
  • Color formers in the widest and most comprehensive meaning of this expression, which is used to include any chemical agent, substance or compound adapted to yield a colored reaction or compound by oxidation, reduction, diazotation, or in any other way.
  • Color formers may be chosen for different types of insulated elements with either of three criteria: different color formers, to react all with a common developer; different color formers, each requiring a developer which does not act with the others; a common color former which reacts differently with different developers; a color former in only one type of elements while another type of elements or an adjoining plain emulsion are provided with no color formers, the whole being intended for use with a developer that is capable of producing a color with the one color former and another by itself.
  • the first of these criteria of choice may appear the simplest and most indicated for amateurs; the second will surely afford the safest and most precise means for best results; the third and fourth require the concomitance of particular aims.
  • Metal salts other than silver, incorporated in the insulated elements either by their presence in precipitation or bysuccessive addition. These may be utilised to mordant dyes that may be present in the elements or emulsion, or to produce metal salt colored images by toning methods, or metal-organic compounds.
  • One and the same material may be provided, in a single layer or in two or more layers. with insulated elements not necessarily all carrying the same basis for color, so that this very difierence may afford means for differentiating treatments.
  • the resins in the elements or layers of a material may be subjected to controlled action of heat to harden, fuse, or generally render more durable the image-bearing layers: to this purpose suitable plasticisers should be embodied in the elements or applied previously to heating.
  • the present invention affords a variety of applications for the production of materials for color photography.
  • EXAMPLE 1 A single layer for three color is composed by mixing three lots of emulsion as follows:
  • First layer is an emulsion produced in usual manner, strongly orthochrpma'tic, to 100 cc. of which is added a solution of 2-amino-5-hydroxytoluene gr. 0.30 in alcohol q. s. Add also tartrazlne gr. 0.25 and naphthol green gr.0.10.
  • Second layer is composed of Lot 1 l A Lot 1 of previous example, with plain" alpha naphthol substitutedgforthe 2:4 dichloralpha naphthol, same quantity as-indicated for the latter.
  • EXAMPLE 3 Two 1 layer material adapted to be processedv at will so as to give either a negative color pic- CJ ture in direct colors (and inverted luminosities) as in Examplel or a negative color picture with direct color in middle band rays (yellow and green) and with complementaries in the extreme band colors (blue for red and red for blue) as in acetoacetanilide in alcohol q. s. are dispersed.
  • the colorv former may be in insulated silver halide grains, if desired-
  • the emulsion is 'made strongly orthochromatic for instance with a solution of ccbalt'salt and green sensitiser as that prescribed for Lot 3 of Example 1, and is to contain tartrazine gr..0.25 and naphthol green 0.15.
  • Second layer is composed of Lot 1 As Lot 1 of Example 1, with alpha naphthol substituted for the 2:4 dichlor alpha naphthol, same quantity.
  • Treatment for direct" middie band and complementary extreme bands develop in the usual sodium carbonate solution and little, if any, sulphite, with about 2 gr. of 5-amino-2-hydroxytoluene hydrochloride (or sulphate) per 1000 cc. of solution. Wash, fix in plain hypo.
  • EXAMPLE 4 A two-layer material, intended for simple and rapid processing, and of the simplest manufacture, as the upper layer may be considered similar to an anti-stress coating:
  • First coat is composed of two lots mixed tog'ether:
  • Mix A and B add C. Warm the whole and add in fine stream to D kept at 60 C. Finish emulsion in recognized manner, and finally dilute, before coating, with equal parts, or thereabout, of this emulsion and a gelatin solution: to every 100 cc. of the latter from gr. 0.20 to gr. 0.40 of tartrazine should be added.
  • the degree of such dilution, strength of gelatin, and quantity of tartrazine depend on the thickness of the layer that the coating appliance employed allows. A thin coat is desired, equal to no more than half the thickness of the first layer.
  • Processing is effected with a biethyl-p-phenylene diamine developer, followed by fixing and subsequent removal of black silver. Some of the latter may, if desired, be left in, when soft color effects are desired. A picture is obtained in negative luminosities but direct colors. For a picture in complementaries, reversal may be applied after black development, but in such case the second color development should contain also a yellow color former, as the acetoacetanilide present free in first layer would not resist the acid reversal bath.
  • EXAMPLE 5 Material mainly intended to give by reversal direct color positives for copying multi-color originals. Three lots are required.
  • Lot 1 This can be an emulsion non-color-sensitised so that it should be only sensitive to blue, and may contain a yellow color former of little solubility, or nothing. Isamine blue could be dispersed in this emulsion.
  • This emulsion is either coated in separate layer under a gelatin suspension of the other two lots, or is mixed with the latter in a single layer.
  • a blue color former say alpha naphthol; Nickel salt;
  • Red sensitiser say pinacyanol
  • Lot 3 This also consists of insulated elements produced similarly to previous instances with:
  • a red color former say p-nitro-benzyl-cyanide; Cobalt salt; Green sensitiser, say orthochrome T;
  • the Lot 1 is made to contain insulated blue sensitive elements comprising also a yellow color former.
  • the black produced in the plain emulsion may finally be re-formed so as to blend the colors in soft harmony.
  • a support of glass, cellulose ester, paper, or other suitable material has thereon a gelatin layer ll containing dispersed particles of resin I2 containing silver halide represented at [3 and color-former represented at l4.
  • resin I2 containing silver halide represented at [3 and color-former represented at l4.
  • Emulsions carrying insulated color elements require much less hardening agent than generally used, if at all-depending, naturally, on the brand of gelatin that is employed.
  • the method of forming a sensitive photo! image which comprises precipitating a silver graphic layer capable of producing a colored image which comprises precipitating a silver halide in a solution of a water-insoluble resin containing a color former and a plasticizer for the resin, suspending particles of the solution of resin containing silver halide, color former and plasticizer in gelatin'and coating the suspension on a support.
  • the method of forming a sensitive photographic layer capable of producing a colored image which comprises mixing a solution of resin color former and a soluble halide with a solution of gelatin and a soluble silver salt to precipitate a silver halide in the solution of resin and color former, suspending particles of the solution of resin containing silver halide and color former in gelatin, and coating the suspension on a support.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
  • Heat Sensitive Colour Forming Recording (AREA)
US394663A 1940-06-03 1941-05-22 Light sensitive color element Expired - Lifetime US2284877A (en)

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GB9657/40A GB543606A (en) 1940-06-03 1940-06-03 Improvements in colour photography

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BE (1) BE469163A (fr)
FR (1) FR942842A (fr)
GB (1) GB543606A (fr)

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2548526A (en) * 1946-12-11 1951-04-10 Eastman Kodak Co Mixed grain photographic emulsions
US2565418A (en) * 1947-08-13 1951-08-21 Eastman Kodak Co Method of preparing photographic silver halide emulsions
US2576850A (en) * 1945-04-26 1951-11-27 Du Pont Gelling of polymeric compounds
US2698794A (en) * 1950-04-15 1955-01-04 Eastman Kodak Co Mixed packet photographic emulsions
US2717833A (en) * 1952-05-12 1955-09-13 Sperry Rand Corp Direct positive emulsions
US2735766A (en) * 1952-05-15 1956-02-21 Prevention of dye wandering in
US2760864A (en) * 1953-03-03 1956-08-28 Eastman Kodak Co Water resistant coatings for photographic paper and method for producing same
US2763552A (en) * 1950-04-15 1956-09-18 Eastman Kodak Co Modifiers for photographic packet emulsions
US2816029A (en) * 1955-03-08 1957-12-10 Eastman Kodak Co Supersensitizing combinations comprising simple cyanine dyes and metal salts
US2819964A (en) * 1955-03-08 1958-01-14 Eastman Kodak Co Supersensitizing combinations comprising meso-substituted carbocyanine dyes and metal salts
US2839405A (en) * 1955-03-08 1958-06-17 Eastman Kodak Co Inorganic salt antifoggants for photographic emulsions
US2843490A (en) * 1955-03-08 1958-07-15 Eastman Kodak Co Supersensitizing combinations comprising meso-substituted carbocyanine dyes and polyvalent metal salts
US2843489A (en) * 1955-07-29 1958-07-15 Eastman Kodak Co Mixed packet photographic emulsions with polyvinyl resin continuous phase
US2852383A (en) * 1955-09-01 1958-09-16 Eastman Kodak Co Preparation of photographic packet emulsions by a water-in-oil system
US2865753A (en) * 1955-12-14 1958-12-23 Eastman Kodak Co Photographic emulsions containing a styrene-butadiene latex and photographic paper made therewith
US2910359A (en) * 1957-08-28 1959-10-27 Du Pont Silver halide emulsions and processes for preparing same
DE1081313B (de) * 1957-11-01 1960-05-05 Gen Aniline & Film Corp Verfahren zur Herstellung eines photographischen Einschichtmaterials fuer die Farbentwicklung nach dem Mischkornprinzip
US3839047A (en) * 1971-08-27 1974-10-01 Konishiroku Photo Ind Light-sensitive silver halide photographic material
US4021247A (en) * 1973-11-13 1977-05-03 Fuji Photo Film Co., Ltd. Method of dispersing organic compounds useful in photography
US4983506A (en) * 1987-10-14 1991-01-08 Fuji Photo Film Co., Ltd. Silver halide photographic material

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE614897A (fr) * 1961-03-10
DE1142757B (de) * 1961-03-14 1963-01-24 Agfa Ag Verfahren zur Verbesserung der Farbwiedergabe bei der Reproduktion von Mehrfarbenbildern mit Hilfe von zwei Farbmasken

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2576850A (en) * 1945-04-26 1951-11-27 Du Pont Gelling of polymeric compounds
US2548526A (en) * 1946-12-11 1951-04-10 Eastman Kodak Co Mixed grain photographic emulsions
US2565418A (en) * 1947-08-13 1951-08-21 Eastman Kodak Co Method of preparing photographic silver halide emulsions
US2698794A (en) * 1950-04-15 1955-01-04 Eastman Kodak Co Mixed packet photographic emulsions
US2763552A (en) * 1950-04-15 1956-09-18 Eastman Kodak Co Modifiers for photographic packet emulsions
US2717833A (en) * 1952-05-12 1955-09-13 Sperry Rand Corp Direct positive emulsions
US2735766A (en) * 1952-05-15 1956-02-21 Prevention of dye wandering in
US2760864A (en) * 1953-03-03 1956-08-28 Eastman Kodak Co Water resistant coatings for photographic paper and method for producing same
US2839405A (en) * 1955-03-08 1958-06-17 Eastman Kodak Co Inorganic salt antifoggants for photographic emulsions
US2819964A (en) * 1955-03-08 1958-01-14 Eastman Kodak Co Supersensitizing combinations comprising meso-substituted carbocyanine dyes and metal salts
US2816029A (en) * 1955-03-08 1957-12-10 Eastman Kodak Co Supersensitizing combinations comprising simple cyanine dyes and metal salts
US2843490A (en) * 1955-03-08 1958-07-15 Eastman Kodak Co Supersensitizing combinations comprising meso-substituted carbocyanine dyes and polyvalent metal salts
US2843489A (en) * 1955-07-29 1958-07-15 Eastman Kodak Co Mixed packet photographic emulsions with polyvinyl resin continuous phase
US2852383A (en) * 1955-09-01 1958-09-16 Eastman Kodak Co Preparation of photographic packet emulsions by a water-in-oil system
US2865753A (en) * 1955-12-14 1958-12-23 Eastman Kodak Co Photographic emulsions containing a styrene-butadiene latex and photographic paper made therewith
US2910359A (en) * 1957-08-28 1959-10-27 Du Pont Silver halide emulsions and processes for preparing same
DE1081313B (de) * 1957-11-01 1960-05-05 Gen Aniline & Film Corp Verfahren zur Herstellung eines photographischen Einschichtmaterials fuer die Farbentwicklung nach dem Mischkornprinzip
US3839047A (en) * 1971-08-27 1974-10-01 Konishiroku Photo Ind Light-sensitive silver halide photographic material
US4021247A (en) * 1973-11-13 1977-05-03 Fuji Photo Film Co., Ltd. Method of dispersing organic compounds useful in photography
US4983506A (en) * 1987-10-14 1991-01-08 Fuji Photo Film Co., Ltd. Silver halide photographic material

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Publication number Publication date
BE469163A (fr)
FR942842A (fr) 1949-02-18
GB543606A (en) 1942-03-05

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