US3335006A - Heated diffusion transfer using leucophthalocyanines - Google Patents

Heated diffusion transfer using leucophthalocyanines Download PDF

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Publication number
US3335006A
US3335006A US303685A US30368563A US3335006A US 3335006 A US3335006 A US 3335006A US 303685 A US303685 A US 303685A US 30368563 A US30368563 A US 30368563A US 3335006 A US3335006 A US 3335006A
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Prior art keywords
transfer material
light
layer
sensitive
leucophthalocyanine
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US303685A
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English (en)
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Konig Anita Von
Mader Helmut
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Agfa Gevaert NV
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Agfa AG
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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
    • G03C8/00—Diffusion transfer processes or agents therefor; Photosensitive materials for such processes
    • G03C8/40—Development by heat ; Photo-thermographic processes
    • G03C8/4006—Development by heat ; Photo-thermographic processes using materials covered by the groups G03C8/04 - G03C8/06
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D231/00—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings
    • C07D231/02—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings
    • C07D231/06—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings having one double bond between ring members or between a ring member and a non-ring member
    • C07D231/08—Heterocyclic compounds containing 1,2-diazole or hydrogenated 1,2-diazole rings not condensed with other rings having one double bond between ring members or between a ring member and a non-ring member with oxygen or sulfur atoms directly attached to ring carbon atoms

Definitions

  • the invention relates to a process and materials for the production of non-laterally reversed images, using a supported photosensitive silver halide emulsion layer which contains developer substances and which is subjected to heat development while in contact with a transfer material.
  • German Patent No. 888,045 It is known from German Patent No. 888,045 to develop exposed silver halide emulsion layers containing reducing substances, by heating.
  • this dry developing process can be combined with a transfer process in which silver salts or, in particular, developer substances are transferred to a transfer material in contact therewith.
  • the transfer layer contains substances which are insensitive to light and which produce colored compounds by reaction with the developer. Since only the unexposed areas of the exposed light-sensitive material contain unused developing agents which are transferred, the resulting print is a non-laterally reversed positive image of the original.
  • the principal object of the present invention is to provide photographic processes for the production of photographic images which are deeply colored and are stable to light by development with heat and photographic ma terials for use in such processes.
  • Other objects and advantages of the process, some of which are referred to specifically hereinafter, will be evident to those skilled in the art to which this invention pertains.
  • This object has been achieved by employing light-sensitive materials, which contain a light-sensitive silver halide emulsion layer containing one or more developing agents of the 3-pyrazolidone series. After imagewise exposure the light-sensitive material is brought into contact with a transfer material which contains a leucophthalocyanine. Both materials while maintained in intimate contact are subjected to a temperature between 80 and 200 C., preferably between 110 and 170 C., for a period of time between /2 second and 3 minutes, preferably between 1 and 30 seconds.
  • the silver halide in the exposed areas of the light-sensitive layer is developed to form a negative silver image and the 3-pyrazolidone developing agent of the unexposed areas of the light-sensitive layer, which remained unused, is transferred into the adjacent areas of the transfer material.
  • the transferred 3-pyrazolidone reduces the leucophthalocyanine that is present in the transfer material thereby forming a deeply colored, positive phthalocyanine dye image, which does not fade even if exposed to sunlight.
  • R represents hydrogen, alkyl having up to 5 carbon atoms, of aryl, preferably a phenyl radical which may be substituted, for example, with lower alkyl or alkoxy groups having up to 3 carbon atoms or halogen such as chlorine or bromine;
  • R represents hydrogen or an acyl group, preferably a lower aliphatic acyl group such as acetyl or propionyl;
  • R R R and R represent hydrogen, an alkyl having up to 5 carbon atoms, aryl preferably a phenyl radical which can be substituted with alkyl or alkoxy having up to 3 carbon atoms or halogen such as chlorine or bromine.
  • the above compounds can be prepared by the processes described in British Patents Nos. 679,677 and 679,- 678 in which the phenimines, which can be prepared by reacting acrylonitrile derivatives with the corresponding hydrazine compounds, are saponified to the 3-pyrazolidone.
  • 3-pyrazolidones may also be prepared by the process described in British Patent No. 703,669, in which the final products are obtained by condensation of esters of acrylic acid or their derivatives with hydrazines. This process is particularly suitable for reaction with unsubstituted hydrazine.
  • the resulting 3-pyrazolidones which are oily materials, can be obtained as crystalline compounds by converting them into the hydrochlorides.
  • the developer is added to the silver halide emulsion layers in concentrations of about 2.5 to 20 g. per liter of casting solution, which corresponds to a concentration of between 0.1 and 2.0 g. per square meter of the dried light-sensitive layer.
  • leucophthalocyanines in this connection colorless or only slightly colored com pounds which are composed of four isoindolenine units arranged in a true phthalocy-aninestructure and which produce on reduction a phthalocyanine dye.
  • the leucophthalocyanines according to the foregoing definition can be used in the metal-free form or in the form' of com plexes with metals that form phthalocyanine complexes, such as cobalt, nickel, copper or zinc.
  • the metal complexes in particular those with cobalt are preferred.
  • This term includes compounds which are known as phthalocyanine-precursors, a term which has been used by B. R. A. Brooks, J. G. Burt, B.
  • the leucophthalocyanines can be produced, for example, by first preparing a phthalocyanine, e.g., a phthalocyanine containing no metal or containing cobalt, nickel, copper or zinc, and then attaching additional groups thereto under oxidizing conditions or by heating a reaction mixture which is suitable for the preparation of a phthalocyanine to a temperature below that required for forming the phthalocyanine, or by eliminating the reduction potential required for the formation of a phthalocyanine.
  • a phthalocyanine e.g., a phthalocyanine containing no metal or containing cobalt, nickel, copper or zinc
  • a phthalocyanine is first formed which is then further converted, within the same reaction mixture, to the leuco stage.
  • a complex-forming metal atom can be introduced into a leucophthalocyanine containing no metal, or a metallic leucophthalocyanine can be prepared from a phthalocyanine free from metal.
  • the leucophthalocyanines can be modified in their structure or solubility by subsequent treatments without thereby losing their essential property of being convertible into a phthalocyanine by reduction, In principle, all leucophthald cyanines, regardless of the method by which they have been prepared, are suitable for the copying process according to the invention.
  • Cobalt leucophthalocyanines are particularly suitable because they are only very slightly colored. Copper or nickel leucophthalocyanines have a yellowish or brownish tinge. Particularly to be mentioned are cobalt leucophthalocyanines of the type Phthalogen Blue IB (trade name of the Wegriken Bayer AG) which has been described in the Zeitschrift fiir Angewandte Chemie, vol. 68, page 145 (1956), and which is regarded as a leucophthalocyanine-cobalt-ethylenediamine complex.
  • N,N-di (Z-aminoethyl ethylenediamine, or N,N-di (2- 2-aminoethyl) aminoethyl) amine N,N-di (Z-aminoethyl ethylenediamine, or N,N-di (2- 2-aminoethyl) aminoethyl) amine
  • OI monoamines such as:
  • n-octadecylamine 3 N-propylamine N-butylamine iso-butylamine dodecylamine tetradecylamine hexadecylamine octadecylamine N-diethylstearylamine allylamine diallylamine diethylamine di-N-propylamine 4 di-N-butylamine N,N-d'irnethyl-ethylendiamine, or tetramethylethylendiamine 1-amino-3 -methylaminoprop an di- 2-aminoethyl -amine 3 -dimethylaminopropylamine 3-diethylaminopropylamine 1 tetramethylendiamine hexamethylendiamine tetraethylenpentamine di( 3 -amino-propyl)-amine l-diethylamino-4-amino-pentane di 3-
  • the constitutents referred to hereinbefore can be split off.
  • Suitable solvents for the leucophthalocyanine are inorganic or organic acids such as amidosulfonic acid, orthophosphoric acid, acetic acid, propionic acid, lactic acid amides such as dimethylformamide, pyrrolidone and N-methylpyrrolidone, alcohols such as methanol, propanol, benzyl alcohol ethylene glycol, ethylene glycol ethyl ether (ethoxy ethanol), polyethylenglycols, esters such as ethoxyethyl acetate, hydrocarbons such as benzene, toluene, chlorobenzene, cyclohexaue and n-hexane, and mixtures of these solvents.
  • inorganic or organic acids such as amidosulfonic acid, orthophosphoric acid, acetic acid, propionic acid, lactic acid amides such as dimethylformamide, pyrrolidone and N-methylpyrrolidone, alcohols such as methanol
  • the transfer material may be saturated with these solutions or the solutions may be added to suitable solutions of film-forming binding agents with which the transfer material is then coated on one or both sides.
  • the leucophthalocyanines may be emulsified in the solutions of binding agents using emulsifiers such as dinaphthyl methansulfonate, oleylalcoholglycolether, using mixing apparatus, vibrating mills and the like.
  • the casting solutions may contain approximately 0.2 to 20 g. per liter of the leucophthalocyanine compound which corresponds to a concentration in the dried transfer material of between 0.01 and 1.0 g. per square meter.
  • binding agents for these layers are cellulose derivatives, e.g., carboxymethyl cellulose, methyl cellulose, methylhydroxyethyl cellulose, polysaccharide and derivatives such as starch ethers, e.g., carboxymethyl starch, gallactomannan, alkali-metal salts of alginic acid,
  • alginic acid esters polyvinyl alcohol, polyvinyl acetate and gelatiue, or mixtures of these binding agents.
  • the adhesion of the positive layer to the negative layer can be modified by the addition of suitable matting agents to the positive or negative layer so that the layers will adhere firmly together without sticking.
  • suitable matting agents such as Superfloss (trade name of the firm Johns-Mansville International C0., New York), finely dispersed silicon dioxide, and silica aerogels such as Aerosil (trade name of the firm Degussa), Vulkasil (trade name of the firm Wegriken Bayer AG) or hydrosols of silicic acids such as Syntharesin (trade name of the Konriken Bayer AG) and finely dispersed aluminum oxide and titanium dioxide.
  • Kieselgur such as Superfloss (trade name of the firm Johns-Mansville International C0., New York), finely dispersed silicon dioxide, and silica aerogels such as Aerosil (trade name of the firm Degussa), Vulkasil (trade name of the firm Wegriken Bayer AG) or hydrosols of silicic acids such as Syn
  • Such substances are compounds which split off water on heating or compounds which increase the residual moisture content of the layer.
  • Compounds of the first mentioned type are urea, salts containing water of crystallization such as sodium citrate or preferably sodium acetate; compounds of the second mentioned type are, for example, polyhydric alcohols such as sorbitol, glycerol or polyethylene glycols. These compounds may be added in such quantities to the casting solution for the negative layer, that the dried layer contain between 0.1 and 25 g. per square meter thereof.
  • the negative and the transfer layers can be applied on any suitable support which is stable at the temperatures of heat development, e.g., paper, baryta-coated paper, film-forming synthetic polymers, such as polycarbonates, in particular of bis-hydroxyphenyl-alkanes, or polyesters of terephthalic acid and ethylene glycol, and also cellulose esters, textile fabrics or metal foils.
  • suitable support which is stable at the temperatures of heat development
  • suitable support which is stable at the temperatures of heat development
  • film-forming synthetic polymers such as polycarbonates, in particular of bis-hydroxyphenyl-alkanes, or polyesters of terephthalic acid and ethylene glycol, and also cellulose esters, textile fabrics or metal foils.
  • the light-sensitive silver halide emulsion layer may contain as light-sensitive silver salts silver chloride, silver bromide or mixtures thereof, if desired with an additional content of up to 5% of silver iodide.
  • the concentration of silver is between 0.5 and 5.0 preferably between 1 and 2 g. per square meter of the dried layer.
  • the lightsensitive layer may contain further additives normally used, such as sensitizing dyes or stabilizers.
  • antioxidants are added to the light-sensitive layers which contain the 3-pyrazolidene developing agents.
  • Suitable antioxidants are, for example: alkali-metal sulfites or metabisulfites such as potassium metabisulfite or sodium sulfite, bisulfite compounds of ketones or aldehydes such as cyclohexanone bisulfite, or salts of hydroxylamine hydrochloride.
  • the light-sensitive layer has a pH-value between about 4.5 and 6.5, preferably between 4.9 and 5.6.
  • EXAMPLE 1 Production of the light-sensitive 'material 30 g. .of crystallized sodium acetate (NaOOCCH 3H O) 20 ml. of a 30% hydrosol of silicic acid with a surface of 200 square meters per gram, 0.5 g. of hydroxylamine hydrochloride and 8 g. of 1-phenyl-3-pyrazolidone are added to 1 liter of a silver halide emulsion, the silver halide of which consists of silver chloride. The pH is adjusted to 5.2 by the addition of acetic acid. The emulsion is applied in known manner to a support such as paper or a foil of a polymeric product and dried.
  • a support such as paper or a foil of a polymeric product and dried.
  • the transfer material 15 g. of a cobalt leucophthalocyanine (the preparation of which is described at the end of this example) are dissolved in 100 ml. of a polyethyleneglycol having an average molecular weight of about 400, 10 ml. of acetic acid and 890 ml. of ethyl alcohol. A paper sheet is impregnated with this solution and dried.
  • the lightv sensitive layer After imagewise exposure to actinic light, the lightv sensitive layer is brought into contact with the transfer material. Both layers are heated, while maintained in intimate contact, to a temperature between 110 and 170 C. for /2 to 10 seconds by means of a developing apparatus as described in Belgian Patent No. 628,174 or by means of a high gloss press or a drying drum. After separation of the papers, a blue image is obtained on a pale yellow background.
  • the cobalt leucophthalocyanine was lows:
  • EXAMPLE 2 Production of the light-sensitive material 30 mg. of 1-phenyl-S-mercaptotetrazole (as a 1% solution in ethyl alcohol), 25 g. of crystalline sodium acetate, 2 g. of potassium metabisulfite and 10 g. of l-phenyl-4- methyl-3-pyrazolidone were added to 1 liter of a silver halide emulsion, the silver halide of which consists of 0.35 mol/l. of silver chloride, containing 0.1% of silver iodide. The pH is adjusted to 4.9 by the addition of sulfuric acid.
  • Transfer material 10 g. of Phthalogen Blue LB. (trade name of Wegwood Bayer AG) prepared according to Example 1 of DBP 940,164 are dissolved in 1 liter of a 6% aqueous solution of acetic acid. After the addition of 12 ml. of a 30% hydrosol of a silicic acid with a surface of 200 square meter per g., a paper is impregnated with this solution and dried.
  • Example 2 The materials are processed as described in Example 1. A blue image of a pale yellow ground is obtained.
  • EXAMPLE 3 Production of the light-sensitive material 0.5 g. of benzotriazole (as a 5% solution in ethyl alcohol), ml. of a 15% hydrosol of a silicic acid having a surface of 100 square meter per g., 15 g. of crystalline sodium acetate, 5 g. of potassium metabisulfite and 10 g. of p-toluene-3-pyrazolidone are added to 1 liter of a silver chloride emulsion. The pH is adjusted to 5.5 by the addition of citric acid. This emulsion is applied on a paper support and dried.
  • a cobalt leucophthalocyanine prepared as described below, dissolved in 30 ml. of a polyethylene glycol having an average molecular weight of about 400
  • 2 ml. of lactic acid, '3 g. of tartaric acid and 5 ml. of a 30% aqueous solution of saponine are added to 1
  • the materials are processed as described in Example 1. A blue image is obtained.
  • the cobalt leucophthalocyanine was prepared from the nitrate referred to in Example 1. 12 g. of this compound 7 were refluxed with 10 ml. N-methyl-N-(2-hydroxyethy1)- 1,3-propylenediamine in 100 ml. of methanol until, after about 15 minutes, the reaction product was uniformly crystallized. The reaction mixture was filtered by suction and the residue washed with methanol and dried. 12 g. of orange yellow crystals were obtained.
  • EXAMPLE 4 0.5 g. of 4-hydroxy-6-methyl-1,2,3,a,7-tetraazaindene (as a 1% solution in ethyl alcohol), 50 g. of crystalline sodium acetate, 2 g. of potassium metabisulfite, g. of cyclopentanone-bisulfite, g. m-toluyl-3-pyrazolidone and 200 ml. of a hydrosol of a silicic acid having a surface of 200 square meter per g. were added to 1 liter of a silver chloride emulsion. The pH was adjusted to 5.2 by addition of sulfuric acid. The emulsion is cast onto a paper support and dried.
  • Transfer material 4 g. of a cobalt leucophthalocyanine prepared according to Example 1 are dissolved in 40 ml. of a polyethylene glycol having an average molecular weight of about 400, 24 ml. of a 30% hydrosol of a silicic acid with a surface of 200 square meter per g., and 5 ml. of a 30% aqueous solution of saponine were added to 1 liter of a 5% aqueous solution of carboxy-methylcellulose. A paper is impregnated with this solution in known manner and dried. The materials are processed as described in Example 1. A blue image is obtained.
  • a process for the production of a non-laterally reversed photographic image which comprises:
  • a light-sensitive transfer material which contains, in an amount between 001 and 1.0 g. per square meter of the transfer material, a leucophthalocyanine that is at most only slightly colored and is composed of 4 isoindolenine units which are arranged in a true phthalocyanine structure and which produce on reduction a phthalocyanine dye;
  • R III in which R is a radical of the group consisting of hydrogen, alkyl containing up to 5 carbon atoms and phenyl; R is a radical of the group consisting of hydrogen and lower aliphatic acyl radicals having up to 5 carbon atoms; and R R R and R are each a radical of the group consisting of hydrogen and alkyl having up to 5 carbon atoms and phenyl.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
  • Heat Sensitive Colour Forming Recording (AREA)
  • Nitrogen Condensed Heterocyclic Rings (AREA)
US303685A 1962-09-15 1963-08-21 Heated diffusion transfer using leucophthalocyanines Expired - Lifetime US3335006A (en)

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DEA41161A DE1165410B (de) 1962-09-15 1962-09-15 Verfahren zur Herstellung seitenrichtiger positiver Kopien durch Waermeentwicklung

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AT (1) AT253355B (en))
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4624910A (en) * 1984-05-25 1986-11-25 Fuji Photo Film Co., Ltd. Image recording process

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2662896A (en) * 1951-10-19 1953-12-15 Du Pont Reversible solvent-soluble derivatives of phthalocyanine pigments
US2681348A (en) * 1952-05-24 1954-06-15 Du Pont Leuco-calcium phthalocyanine and process of making the same
US2884326A (en) * 1955-04-06 1959-04-28 Du Pont Leuco phthalocyanine and diazo compound in photographic element
US2892710A (en) * 1957-07-10 1959-06-30 Polaroid Corp Photographic products and processes
US2909430A (en) * 1958-10-08 1959-10-20 Polaroid Corp Photographic processes
US2971840A (en) * 1955-02-07 1961-02-14 Agfa Ag Process for the production of nonlaterally reversed positive copies by heat development
US3178285A (en) * 1960-03-24 1965-04-13 Ciba Ltd Photographic layers for the silver dyestuff bleaching process

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2662896A (en) * 1951-10-19 1953-12-15 Du Pont Reversible solvent-soluble derivatives of phthalocyanine pigments
US2681348A (en) * 1952-05-24 1954-06-15 Du Pont Leuco-calcium phthalocyanine and process of making the same
US2971840A (en) * 1955-02-07 1961-02-14 Agfa Ag Process for the production of nonlaterally reversed positive copies by heat development
US2884326A (en) * 1955-04-06 1959-04-28 Du Pont Leuco phthalocyanine and diazo compound in photographic element
US2892710A (en) * 1957-07-10 1959-06-30 Polaroid Corp Photographic products and processes
US2909430A (en) * 1958-10-08 1959-10-20 Polaroid Corp Photographic processes
US3178285A (en) * 1960-03-24 1965-04-13 Ciba Ltd Photographic layers for the silver dyestuff bleaching process

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4624910A (en) * 1984-05-25 1986-11-25 Fuji Photo Film Co., Ltd. Image recording process

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BE637359A (en))
AT253355B (de) 1967-04-10
GB993598A (en) 1965-05-26
DE1165410B (de) 1964-03-12

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