US3257205A - Method for heat development - Google Patents
Method for heat development Download PDFInfo
- Publication number
- US3257205A US3257205A US147388A US14738861A US3257205A US 3257205 A US3257205 A US 3257205A US 147388 A US147388 A US 147388A US 14738861 A US14738861 A US 14738861A US 3257205 A US3257205 A US 3257205A
- Authority
- US
- United States
- Prior art keywords
- layer
- silver halide
- silver
- pyrazolidone
- phenyl
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- 238000011161 development Methods 0.000 title claims description 16
- 238000000034 method Methods 0.000 title claims description 13
- -1 SILVER HALIDE Chemical class 0.000 claims description 33
- 229910052709 silver Inorganic materials 0.000 claims description 27
- 239000004332 silver Substances 0.000 claims description 27
- 239000000839 emulsion Substances 0.000 claims description 26
- 239000000463 material Substances 0.000 claims description 25
- 150000001875 compounds Chemical class 0.000 claims description 10
- 230000008569 process Effects 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- NDGRWYRVNANFNB-UHFFFAOYSA-N pyrazolidin-3-one Chemical compound O=C1CCNN1 NDGRWYRVNANFNB-UHFFFAOYSA-N 0.000 claims description 2
- 239000000126 substance Substances 0.000 description 11
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 10
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 description 8
- 239000000725 suspension Substances 0.000 description 7
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 6
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 6
- 125000000623 heterocyclic group Chemical group 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- 239000002253 acid Substances 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 230000005855 radiation Effects 0.000 description 5
- JXCNUCFTHLGXDQ-UHFFFAOYSA-N 2h-tetrazol-2-ium;chloride Chemical compound Cl.C1=NN=NN1 JXCNUCFTHLGXDQ-UHFFFAOYSA-N 0.000 description 4
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 4
- JBKVHLHDHHXQEQ-UHFFFAOYSA-N epsilon-caprolactam Chemical compound O=C1CCCCCN1 JBKVHLHDHHXQEQ-UHFFFAOYSA-N 0.000 description 4
- 239000008098 formaldehyde solution Substances 0.000 description 4
- CMCWWLVWPDLCRM-UHFFFAOYSA-N phenidone Chemical compound N1C(=O)CCN1C1=CC=CC=C1 CMCWWLVWPDLCRM-UHFFFAOYSA-N 0.000 description 4
- 229910001961 silver nitrate Inorganic materials 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 3
- 229910021607 Silver chloride Inorganic materials 0.000 description 3
- 125000001931 aliphatic group Chemical group 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 150000005840 aryl radicals Chemical group 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 239000002609 medium Substances 0.000 description 3
- SYXUBXTYGFJFEH-UHFFFAOYSA-N oat triterpenoid saponin Chemical compound CNC1=CC=CC=C1C(=O)OC1C(C=O)(C)CC2C3(C(O3)CC3C4(CCC5C(C)(CO)C(OC6C(C(O)C(OC7C(C(O)C(O)C(CO)O7)O)CO6)OC6C(C(O)C(O)C(CO)O6)O)CCC53C)C)C4(C)CC(O)C2(C)C1 SYXUBXTYGFJFEH-UHFFFAOYSA-N 0.000 description 3
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 3
- 125000003831 tetrazolyl group Chemical group 0.000 description 3
- DGBNUTJYQXQLSV-UHFFFAOYSA-N 1h-triazol-1-ium;chloride Chemical compound Cl.C1=CNN=N1 DGBNUTJYQXQLSV-UHFFFAOYSA-N 0.000 description 2
- 108010010803 Gelatin Proteins 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- VMHLLURERBWHNL-UHFFFAOYSA-M Sodium acetate Chemical compound [Na+].CC([O-])=O VMHLLURERBWHNL-UHFFFAOYSA-M 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 125000004429 atom Chemical group 0.000 description 2
- YCIMNLLNPGFGHC-UHFFFAOYSA-N catechol Chemical compound OC1=CC=CC=C1O YCIMNLLNPGFGHC-UHFFFAOYSA-N 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 239000000975 dye Substances 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 229920000159 gelatin Polymers 0.000 description 2
- 239000008273 gelatin Substances 0.000 description 2
- 235000019322 gelatine Nutrition 0.000 description 2
- 235000011852 gelatine desserts Nutrition 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 229920001223 polyethylene glycol Polymers 0.000 description 2
- 150000003254 radicals Chemical class 0.000 description 2
- 150000003378 silver Chemical class 0.000 description 2
- 125000001425 triazolyl group Chemical group 0.000 description 2
- CYXJEHCKVOQFOV-UHFFFAOYSA-N (4-amino-2-methylphenyl) hydrogen sulfate Chemical compound CC1=CC(N)=CC=C1OS(O)(=O)=O CYXJEHCKVOQFOV-UHFFFAOYSA-N 0.000 description 1
- ORQRILZGUPTVLY-UHFFFAOYSA-N 2,3-diphenyl-1H-benzo[e]benzotriazol-1-ium chloride Chemical compound [Cl-].C1(=CC=CC=C1)N1N(C2=C([NH2+]1)C1=CC=CC=C1C=C2)C2=CC=CC=C2 ORQRILZGUPTVLY-UHFFFAOYSA-N 0.000 description 1
- LZKDSAWLUOPHRU-UHFFFAOYSA-N 2-(4-methoxyphenyl)-3,5-diphenyl-1h-tetrazol-1-ium;chloride Chemical compound [Cl-].C1=CC(OC)=CC=C1N1N(C=2C=CC=CC=2)N=C(C=2C=CC=CC=2)[NH2+]1 LZKDSAWLUOPHRU-UHFFFAOYSA-N 0.000 description 1
- GCYDZZBQYRCILB-UHFFFAOYSA-N 2-acetyl-1-phenylpyrazolidin-3-one Chemical compound C1CC(=O)N(C(=O)C)N1C1=CC=CC=C1 GCYDZZBQYRCILB-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- ZDXPYRJPNDTMRX-VKHMYHEASA-N L-glutamine Chemical compound OC(=O)[C@@H](N)CCC(N)=O ZDXPYRJPNDTMRX-VKHMYHEASA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 229940040526 anhydrous sodium acetate Drugs 0.000 description 1
- 239000012736 aqueous medium Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000004305 biphenyl Substances 0.000 description 1
- 235000010290 biphenyl Nutrition 0.000 description 1
- 229910052793 cadmium Inorganic materials 0.000 description 1
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- ARUVKPQLZAKDPS-UHFFFAOYSA-L copper(II) sulfate Chemical compound [Cu+2].[O-][S+2]([O-])([O-])[O-] ARUVKPQLZAKDPS-UHFFFAOYSA-L 0.000 description 1
- 229910000366 copper(II) sulfate Inorganic materials 0.000 description 1
- 238000003618 dip coating Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229940042795 hydrazides for tuberculosis treatment Drugs 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 210000001699 lower leg Anatomy 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- ZUOUZKKEUPVFJK-UHFFFAOYSA-N phenylbenzene Natural products C1=CC=CC=C1C1=CC=CC=C1 ZUOUZKKEUPVFJK-UHFFFAOYSA-N 0.000 description 1
- HKOOXMFOFWEVGF-UHFFFAOYSA-N phenylhydrazine Chemical group NNC1=CC=CC=C1 HKOOXMFOFWEVGF-UHFFFAOYSA-N 0.000 description 1
- 229940067157 phenylhydrazine Drugs 0.000 description 1
- 239000004014 plasticizer Substances 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- RWPGFSMJFRPDDP-UHFFFAOYSA-L potassium metabisulfite Chemical compound [K+].[K+].[O-]S(=O)S([O-])(=O)=O RWPGFSMJFRPDDP-UHFFFAOYSA-L 0.000 description 1
- 229940043349 potassium metabisulfite Drugs 0.000 description 1
- 235000010263 potassium metabisulphite Nutrition 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical compound [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 description 1
- 239000001632 sodium acetate Substances 0.000 description 1
- 235000017281 sodium acetate Nutrition 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 239000004408 titanium dioxide Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Classifications
-
- 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
- G03C1/42—Developers or their precursors
-
- 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
- G03C11/00—Auxiliary processes in photography
- G03C11/08—Varnishing, e.g. application of protective layers on finished photographic prints
-
- 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
Definitions
- Suitable reducing compounds for heat development processes are aromatic amino-, hydroxy-, and aminohydroxy-compounds and their derivatives, many examples of which are described in German patent specification 895,101 and Belgian patent specifications 544,850,
- the image obtained is of an inferior quality because of the too low density and the too soft gradation of the light-sensitive material.
- a process has been found for the production of photographic images by heatdevelopment, wherein a photographic material comprising a silver halide emulsion layer and incorporated in this silver halide emulsion layer and/or in a layer adjacent thereto, a S-pyrazolidone compound of the formula wherein:
- the pH of the silver halide emulsion during the heat-development being 7 or less.
- the developing substances according to this invention may be incorporated, either into the silver halide emulsion or into a separate adjacent layer.
- the developability of the above described silver halide emulsions can still be improved by incorporating into these emulsions compounds which on heating liberate water.
- hydrophilic plasticizers e.g., glycerol, caprolactam, polyethylene glycol and the like
- hydrophilic plasticizers e.g., glycerol, caprolactam, polyethylene glycol and the like
- the image quality can be improved by incorporating into the emulsions compounds which favorably influence the image tone, e.g., l-phenyl-S-mercaptotet-razole or similar products, which are described in British patent specification 561,875 and Belgian patent specification 502,525.
- An advantage of the new process is the excellent quality of the produced images with regard to the density as well V as in respect of the gradation. After rinsing and fixing, the obtained density is also much better kept than it is in the case with the most known developing substances.
- a second advantage is the short developing time: in some cases the development has to last for only 1 to 10 sec. at a temperature between and 200 C. Furthermore, the material according to the invention has very good keeping properties'before its exposure, as derivatives of 1-phenyl-3-pyrazolidone in a non-alkaline medium and a normal temperature show but a poor reactivity.
- a further advantage is the broad thermal margin of working up or the silver halide emulsions which are prepared with these new compounds. It has been experienced that the temperature fluctuations during the heatdevelopment may amount to 30 to 40 C. without incurring the risk that less good images are obtained.
- the amount of warmth which is necessary for the development may be applied onto the material in various waves possess a wave-length of to 10" cm.
- the silver halide emulsion can be developed by conduction, by contacting it with heated plates or rollers, by placing it between two capacitor plates which are subjected to a high frequency field, or by subjecting it to the Joule effect.
- the silver halide emulsion can also be developed by convection, e.g., by contacting it with directed warm gas stream. For this purpose, e.g., warm air or steam may be used.
- the silver halide emulsion can also be developed by warmth radiation.
- the use of infrared radiation sources is especially suited therefor, not only because they have an intensive developing power, but also because they enable simultaneously to expose and to develop in a fraction of a second.
- infrared radiation sources those radiation sources are understood of which the major part of the radiated energy In this way it is possible to contact a light-sensitive material, prepared according to this invention, with a film negative and to move it along a light-source which is rich in infrared radiations so as to obtain immediately a very strong positive image.
- An especially interesting embodiment of this invention is the manufacture of prints of the heat-developed images according to the transfer process, which is described in the German patent specification 895,101.
- the silver halide layers which are developable by heat contain a developing sub- 4, (1,2)triazolium chloride and 2-phenyl-3-(o-carboxyphenyl) -naphtho 1,2) triazolium chloride.
- tetrazolium compounds according to the above Formula III which appeared from the experiments to give particularly good results are, e.g., 2,5-diphenyl-3-(o-carboxyphenyl)-2,l,3,4-tetrazoliurn chloride, 2,5-diphenyl-3- (o-methoxyphenyl)-2,l,3,4-tetrazolium chloride and 2,5- diphenyl 3 (p-methoxyphenyU-Z,1,3,4-tetrazolium chloride.
- the process according to the present invention can be carried out by contacting the negative layer containing the developing substance, before the heatdevelopment, with a positive layer containing a colorless triazolium compound of the general formula wherein:
- each of R and R represents an aliphatic group, a substituted aliphatic group, a homocyclic group, a substituted homocyclic group, a heterocyclic group, or a substituted heterocyclic group;
- X represents an acid radical
- Y represents the necessary atoms for closing an homocyclic group, substituted homocyclic group, a heterocyclic group, or a substituted heterocyclic group.
- the negative layer is contacted, before the heatdevelopment, with a positive layer which contains a colorless tetrazolium compound of the formula:
- the color tone, the fastness to light and the fastness to washing of these dyes can markedly be improved by the presence in the positive material of salts of multivalent metals, e.g., zinc, copper,
- R is an aryl radical, which in its ortho position bears an electronegative group such as a canboxyl group.
- Another interesting embodiment of this invention is based on the formation of a silver image in the positive material.
- the exposed negative is contacted during the heat-development with a positive material containing silver salts, e.g., silver nitrate.
- the developing substances which remain unused during the heatdeveloprnent diffuse into the positive layer and there reduce the silver salts into metallic silver.
- the silver halide emulsion layers in the dried light-sensitive materials preferably contain per sq. m. 3 g. of gelatin and an amount of silver halide corresponding to 1 g. of silver.
- Example 1 A photographic paper support of 90 g./ sq. m. is coated with a layer from a suspension of the following composi- This paper is then dried, exposed through an original and heat-developed either by contacting this paper with a plate heated at 200 C. or by treating it with a steam jet of 100 C. A sharp print of the original is obtained. This print may be fixed and stabilized according to known processes.
- Example 2 A photographic paper support of -g./sq. m. is coated with a layer from a suspension of the following composition:
- Example 3 A photographic paper support of 90 g./sq. m. is coated with a layer from a suspension of the following composition:
- Example 4 A negative material is prepared by coating a paper support of 90 g./sq. m. with a layer from a suspension of This layer is applied in such a way that 1 l. of this suspension covers 10 sq. m. of paper. Upon this layer is then applied a layer from the following solution:
- a positive material is prepared by dip-coating a paper support of 90 g./sq. m. with a 0.1% aqueous silver nitrate solution and drying it.
- the silver halide emulsion side of the negative material, 'in contact with the original, is reflectographically exposed.
- the negative material is pressed for about 5 sec. with its emulsion side against the prepared positive material by means of a flat-iron at about 150 C.
- the part of developing substance which during the heat-development did not serve to reduce the silver halide into silver, diffuses onto the positive layer and reduces the silver nitrate into silver. A clear print of the original is obtained.
- Example 5 A photographic paper support of 90 g./ sq. m. is coated with a layer from a suspension of the following composition:
- Silver chloride emulsion cm. 100 Water cm. l Ethanol cm. 1-phenyl-3-pyrazolidone g 1 Potassium metabisulfite g 1 Sodium acetate g 20 99% acetic acid cm. 3 Saponine cm. 0.5 40% aqueous formaldehyde solution cm. 0.5 1% solution of l-phenyl-S-mercapto-l,2,3,4-tetrazole in ethanol cm. 2.5 Titanium dioxide g 6 This layer is applied in such a way, that 1 l. of this suspension covers 10 sq. m. of paper.
- a positive material is prepared by coating a paper support of 90 g./sq. m. with a layer from a solution of the following composition:
- the negative material is refiectographically exposed to a printed original and developed by pressing it for 10 sec. against a heated plate at 110 C. Then the developed the following composition:
- a process for the production of photographic copies by heat development which comprises the steps of:
- R is a member of the group consisting of hydrogen and an aryl radical
- R is a member of the group consisting of hydrogen and an acyl radical
- R R R and R are each a member of the group consisting of hydrogen, an alkyl radical and an aryl radical
- R and R are each a member of the group consisting of an aliphatic group, a homocyclic group, and a heterocyclic group,
- X is an acid radical
- Y represents the atoms necessary for closing a ring of the group consisting of a homocyclic ring and a heterocyclic ring;
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
Description
United States Patent 3,257,205 METHOD FOR HEAT DEVELOPMENT Paul Maria Cassiers, Mortsel-Antwerp, Louis Maria De Claims. c1. 96- 29) This invention relates to an improved method for the manufacture of photographic images by a dry processing of photographic silver halide emulsions and to material for the application of this method.
It is known from the German patent specification 888,- 045 that photographic layers can be obtained which are developable by heat,-by incorporating into silver halide emulsions substances which reduce silver halide salts, such as hydrazine, phenyl hydrazine, acid hydrazides, semiice good results when used in this new method, are identified hereinafter:
1-phenyl-3-pyrazolidone l-(m-tolyl) -3-pyrazolidone 1 phenyl-2-acetyl-3-pyrazolidone 1-phenyl-4 methyl-3-pyrazolidone l-phenyl-5-methyl-3-pyrazolidone 1-phenyl-4,4-dimethyl-B-pyrazolidone 1-phenyl-5,5-dimethyl-3-pyrazolidone 1,5 -diphenyl-3-pyrazolidone l-(rn-tolyl) -5-phenyl-3-pyrazolidone 1-(ptolyl)-5-phenyl-3-pyrazolidone carbazides, methyl-p-aminophenol sulphate, hydroquinone and pyrocatechol.
Other suitable reducing compounds for heat development processes are aromatic amino-, hydroxy-, and aminohydroxy-compounds and their derivatives, many examples of which are described in German patent specification 895,101 and Belgian patent specifications 544,850,
545,042 and 555,103.
The use of the developing substances, however, which are described in these patent specifications, involved various disadvantages. Especially the keeping quality of such emulsions before exposure leaves much to be desired.
Also the image obtained is of an inferior quality because of the too low density and the too soft gradation of the light-sensitive material.
According to the present invention a process has been found for the production of photographic images by heatdevelopment, wherein a photographic material comprising a silver halide emulsion layer and incorporated in this silver halide emulsion layer and/or in a layer adjacent thereto, a S-pyrazolidone compound of the formula wherein:
after or during exposureto an object to be reproduced, is subjected to a heat treatment, the pH of the silver halide emulsion during the heat-development being 7 or less.
Some compounds according to the present invention, which appeared from the experiments to give particularly 5-phenyl-3-pyr-azolidone The developing substances according to this invention may be incorporated, either into the silver halide emulsion or into a separate adjacent layer.
The best known of these developing substances viz. l-p-henyl-B-pyrazolidone on itself possesses only poor developing properties as far as development in aqueous medium is concerned (J. D. Kendall, Brit. J. Phot. (1951) 539). It is really surprising that these substances, even when used in the absence of any other developing substance, possess a high developing power if used in a pho-v tographic material subjected to heat-development. Still more unexpected is the fact that this strong developing power even occurs not only in neutral and weak acid medium, but even in relatively strong acid medium, e.g., of pH 4.5.
The developability of the above described silver halide emulsions can still be improved by incorporating into these emulsions compounds which on heating liberate water.
The use of hydrophilic plasticizers, e.g., glycerol, caprolactam, polyethylene glycol and the like, also results into an improvement of the heat-developa-bility. Also in this kind of emulsions the image quality can be improved by incorporating into the emulsions compounds which favorably influence the image tone, e.g., l-phenyl-S-mercaptotet-razole or similar products, which are described in British patent specification 561,875 and Belgian patent specification 502,525.
An advantage of the new process is the excellent quality of the produced images with regard to the density as well V as in respect of the gradation. After rinsing and fixing, the obtained density is also much better kept than it is in the case with the most known developing substances.
A second advantage is the short developing time: in some cases the development has to last for only 1 to 10 sec. at a temperature between and 200 C. Furthermore, the material according to the invention has very good keeping properties'before its exposure, as derivatives of 1-phenyl-3-pyrazolidone in a non-alkaline medium and a normal temperature show but a poor reactivity.
A further advantage is the broad thermal margin of working up or the silver halide emulsions which are prepared with these new compounds. It has been experienced that the temperature fluctuations during the heatdevelopment may amount to 30 to 40 C. without incurring the risk that less good images are obtained.
The amount of warmth which is necessary for the development may be applied onto the material in various waves possess a wave-length of to 10" cm.
ways. So the silver halide emulsion can be developed by conduction, by contacting it with heated plates or rollers, by placing it between two capacitor plates which are subjected to a high frequency field, or by subjecting it to the Joule effect. The silver halide emulsion can also be developed by convection, e.g., by contacting it with directed warm gas stream. For this purpose, e.g., warm air or steam may be used. Finally the silver halide emulsion can also be developed by warmth radiation. The use of infrared radiation sources is especially suited therefor, not only because they have an intensive developing power, but also because they enable simultaneously to expose and to develop in a fraction of a second. By infrared radiation sources those radiation sources are understood of which the major part of the radiated energy In this way it is possible to contact a light-sensitive material, prepared according to this invention, with a film negative and to move it along a light-source which is rich in infrared radiations so as to obtain immediately a very strong positive image.
An especially interesting embodiment of this invention is the manufacture of prints of the heat-developed images according to the transfer process, which is described in the German patent specification 895,101. As is described in that German patent specification the silver halide layers which are developable by heat, contain a developing sub- 4, (1,2)triazolium chloride and 2-phenyl-3-(o-carboxyphenyl) -naphtho 1,2) triazolium chloride.
Some tetrazolium compounds according to the above Formula III which appeared from the experiments to give particularly good results are, e.g., 2,5-diphenyl-3-(o-carboxyphenyl)-2,l,3,4-tetrazoliurn chloride, 2,5-diphenyl-3- (o-methoxyphenyl)-2,l,3,4-tetrazolium chloride and 2,5- diphenyl 3 (p-methoxyphenyU-Z,1,3,4-tetrazolium chloride.
stance which, by reduction of the silver halide to silver on the exposed image areas, is used up and which on the unexposed image areas diffuses under the influence of the supplied warmth into an image-receiving layer brought into contact with the silver halide emulsion layer.
Analogously the process according to the present invention can be carried out by contacting the negative layer containing the developing substance, before the heatdevelopment, with a positive layer containing a colorless triazolium compound of the general formula wherein:
each of R and R (equal or different) represents an aliphatic group, a substituted aliphatic group, a homocyclic group, a substituted homocyclic group, a heterocyclic group, or a substituted heterocyclic group;
X represents an acid radical, and
Y represents the necessary atoms for closing an homocyclic group, substituted homocyclic group, a heterocyclic group, or a substituted heterocyclic group.
Such triazolium compounds are described, e.g., in French patent specification 998,055.
According to another embodiment of the present invention, the negative layer is contacted, before the heatdevelopment, with a positive layer which contains a colorless tetrazolium compound of the formula:
The development substances which remained unused during the heat-development, diffuse into the positive layer and there reduce the above .mentioned colorless triazolium and tetrazolium compounds to dyes. The color tone, the fastness to light and the fastness to washing of these dyes can markedly be improved by the presence in the positive material of salts of multivalent metals, e.g., zinc, copper,
iron, cadmium, cobalt, nickel, chromium, titanium, molybdenum, or tungsten, if tetrazolium compounds are used wherein R is an aryl radical, which in its ortho position bears an electronegative group such as a canboxyl group.
Another interesting embodiment of this invention is based on the formation of a silver image in the positive material. For this purpose, the exposed negative is contacted during the heat-development with a positive material containing silver salts, e.g., silver nitrate. The developing substances which remain unused during the heatdeveloprnent diffuse into the positive layer and there reduce the silver salts into metallic silver.
The following examples illustrate the invention without limiting, however, the scope thereof. The silver halide emulsion layers in the dried light-sensitive materials preferably contain per sq. m. 3 g. of gelatin and an amount of silver halide corresponding to 1 g. of silver.
Example 1 A photographic paper support of 90 g./ sq. m. is coated with a layer from a suspension of the following composi- This paper is then dried, exposed through an original and heat-developed either by contacting this paper with a plate heated at 200 C. or by treating it with a steam jet of 100 C. A sharp print of the original is obtained. This print may be fixed and stabilized according to known processes.
Example 2 A photographic paper support of -g./sq. m. is coated with a layer from a suspension of the following composition:
Silver bromide emulsion g 1000 Water ..cm... 465 Ethanol crus ...v 400 1-phenyl-3-pyrazolidone g 25 Caprolactam g Saponine g 5 40% aqueous formaldehyde solution cm. 5
After further treatment, exposure and heat-development as in Example 1, a sharp print of the original is obtained.
Example 3 A photographic paper support of 90 g./sq. m. is coated with a layer from a suspension of the following composition:
Silver chloride emulsion 'g 1000 Water cm. 465 Ethanol cm. 400
5 p Carbowax 200 (trade name of Union Carbide and Carbon, New York, N.Y., for a polyethylene After further treatment, exposure and heat-development as in Example 1, a sharp print of the original is obtained.
Example 4 A negative material is prepared by coating a paper support of 90 g./sq. m. with a layer from a suspension of This layer is applied in such a way that 1 l. of this suspension covers 10 sq. m. of paper. Upon this layer is then applied a layer from the following solution:
Ethanol cm. 1000 l-phenyl-3-pyrazolidone g 50 This layer is applied in such a manner that 1 l. of this solution covers 20 sq. m. of paper.
A positive material is prepared by dip-coating a paper support of 90 g./sq. m. with a 0.1% aqueous silver nitrate solution and drying it.
The silver halide emulsion side of the negative material, 'in contact with the original, is reflectographically exposed. The negative material is pressed for about 5 sec. with its emulsion side against the prepared positive material by means of a flat-iron at about 150 C.
The part of developing substance which during the heat-development did not serve to reduce the silver halide into silver, diffuses onto the positive layer and reduces the silver nitrate into silver. A clear print of the original is obtained.
Example 5 A photographic paper support of 90 g./ sq. m. is coated with a layer from a suspension of the following composition:
Silver chloride emulsion cm. 100 Water cm. l Ethanol cm. 1-phenyl-3-pyrazolidone g 1 Potassium metabisulfite g 1 Sodium acetate g 20 99% acetic acid cm. 3 Saponine cm. 0.5 40% aqueous formaldehyde solution cm. 0.5 1% solution of l-phenyl-S-mercapto-l,2,3,4-tetrazole in ethanol cm. 2.5 Titanium dioxide g 6 This layer is applied in such a way, that 1 l. of this suspension covers 10 sq. m. of paper.
A positive material is prepared by coating a paper support of 90 g./sq. m. with a layer from a solution of the following composition:
5% aqueous solution of gelatin cm. 50 l aqueous solution of 2,5-diphenyl-3-(p-methoxyphenyl)-2,1,3,4-tetrazolium chloride CIIL3 10% aqueous solution of cupric sulfate cm. 5 20 g. of anhydrous sodium acetate dissolved in water to cm. 24 10% aqueous formaldehyde solution cm. 0.5
The negative material is refiectographically exposed to a printed original and developed by pressing it for 10 sec. against a heated plate at 110 C. Then the developed the following composition:
Silver chloride emulsion g 1000 .Water cm. 1000 Glycerol cm. 100 Saponine g 5 aqueous formaldehyde solution cm. 2
negative material is contacted with the positive material for 20 sec. at C. After separation of the materials, a strong red print of the original is obtained onto the positive material.
Examples 6-7 Similar results are obtained by replacing in the above solution the 2,5 diphenyl-3-(p methoxyphenyl)-2,l,3,4- tetrazolium chloride by a same amount of 2,5-diphenyl-3- (o-methoxyphenyl)-2,l,3,4-tetrazolium chloride or 2,3-diphenylnaphtho (1,2)triazolium chloride.
We claim:
1. A process for the production of photographic copies by heat development which comprises the steps of:
(1) Exposing to the object to be copied a photographic material comprising a silver halide emulsion layer and containing a compound liberating moisture on heating and a 3-pyrazolidone developing compound of the general formula:
R5 N R5 G/ \NR2 R4C-CO wherein:
R is a member of the group consisting of hydrogen and an aryl radical, R is a member of the group consisting of hydrogen and an acyl radical, and R R R and R are each a member of the group consisting of hydrogen, an alkyl radical and an aryl radical;
(2) Developing said exposed emulsion layer by subjecting said layer to a heat treatment at a pH of not more than 7 while said material is maintained in effective separable contact with an image-receiving layer containing an initially colorless image-forming compound selected from the group consisting of (1) silver nitrate, (2) a triazolium compound having the general formula:
wherein:
R and R are each a member of the group consisting of an aliphatic group, a homocyclic group, and a heterocyclic group,
X is an acid radical, and
Y represents the atoms necessary for closing a ring of the group consisting of a homocyclic ring and a heterocyclic ring;
and (3) a tetrazolium compound having the general formula:
N l T (References on following page) UNITED STATES PATENTS 554 934 3/32; geigium. e glum. et 998,055 1/1952 France. James 9629 5 1,003,578 9/1952 Germany. Allan 96109 670,883 4/1952 Great Britain. Hydn et a1. 9629 845,928 8/1960 Great Britain. Hydn et a1. Herrick et aL d 96*29 NORMAN G. TORCHIN, Przmary Examiner. Haist et a1. 96-95 10 LOUISE 'P. QUAST, Examiner. Roth 9629 FOREIGN PATENTS J. T. BROWN, Assistant Examiner.
Claims (1)
1. A PROCESS FOR THE PRODUCTION OF PHOTOGRAPHIC COPIES BY HEAT DEVELOPMENT WHICH COMPRISES THE STEPS OF: (1) EXPOSING TO THE OBJECT TO BE COPIED A PHOTOGRAPHIC MATERIAL COMPRISING A SILVER HALIDE EMULSION LAYER AND CONTAINING A COMPOUND LIBERATING MOISTURE ON HEATING AND A 3-PYRAZOLIDONE DEVELOPING COMPOUND OF THE GENERAL FORMULA:
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL256771 | 1960-10-12 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3257205A true US3257205A (en) | 1966-06-21 |
Family
ID=19752627
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US147388A Expired - Lifetime US3257205A (en) | 1960-10-12 | 1961-10-10 | Method for heat development |
Country Status (6)
Country | Link |
---|---|
US (1) | US3257205A (en) |
BE (1) | BE609057A (en) |
CH (1) | CH397734A (en) |
DE (1) | DE1422887A1 (en) |
GB (1) | GB1001702A (en) |
NL (2) | NL110284C (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3352682A (en) * | 1963-09-13 | 1967-11-14 | Ilford Ltd | Photographic silver halide emulsion containing finely divided uinert particles dispersed in a synthetic colloid medium and a silver halide developer |
US3503741A (en) * | 1966-11-04 | 1970-03-31 | Eastman Kodak Co | Silver-dye-bleach process utilizing formazan dyes |
US3617289A (en) * | 1966-12-10 | 1971-11-02 | Fuji Photo Film Co Ltd | Stabilization process for thermally developable light-sensitive elements |
US3649158A (en) * | 1967-08-08 | 1972-03-14 | Oreal | Process for dyeing locks of human hair with tetragolium salts |
US3880659A (en) * | 1973-08-02 | 1975-04-29 | Eastman Kodak Co | Triazolium salt photoreductive imaging |
US4187108A (en) * | 1977-02-07 | 1980-02-05 | Eastman Kodak Company | Heat developable material and process |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1288427B (en) * | 1963-11-15 | 1969-01-30 | Eastman Kodak Co | Use of 3-pyrazolidones substituted in the 2-position as photographic developer compounds |
DE3870715D1 (en) * | 1987-06-04 | 1992-06-11 | Konishiroku Photo Ind | METHOD FOR PRODUCING PHOTOGRAPHIC PAPER CONTAINING SILVER HALOGENIDE. |
US5206112A (en) * | 1991-06-27 | 1993-04-27 | Minnesota Mining And Manufacturing Company | Positive imaging diffusion - transfer dry silver system |
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BE554934A (en) * | 1956-02-13 | 1900-01-01 | ||
FR998055A (en) * | 1949-09-28 | 1952-01-14 | Gevaert Photo Prod Nv | Process for the production of photographic images |
GB670883A (en) * | 1949-06-21 | 1952-04-30 | Gevaert Photo Prod Nv | Improvements in or relating to the production of photographic images |
US2751300A (en) * | 1954-07-15 | 1956-06-19 | Eastman Kodak Co | Photographic solvent transfer reproduction process |
US2751297A (en) * | 1953-08-03 | 1956-06-19 | Eastman Kodak Co | Photographic emulsion layer containing a 3-pyrazolidone |
DE1003578B (en) * | 1952-09-04 | 1957-02-28 | Zindler Lumoprint Kg | Process for producing photographic images and means for carrying out the same |
US2891862A (en) * | 1956-11-06 | 1959-06-23 | Eastman Kodak Co | Stabilized photographic silver halide emulsions |
GB845928A (en) * | 1957-10-25 | 1960-08-24 | Ilford Ltd | Improvements in or relating to photographic emulsions |
US2971840A (en) * | 1955-02-07 | 1961-02-14 | Agfa Ag | Process for the production of nonlaterally reversed positive copies by heat development |
US3007795A (en) * | 1955-02-11 | 1961-11-07 | Agfa Ag | Process for the production of laterally non-reversed positive copies by heat development |
US3015562A (en) * | 1958-05-07 | 1962-01-02 | Gen Aniline & Film Corp | Receiving sheet for use in photographic silver transfer process |
US3041170A (en) * | 1959-10-29 | 1962-06-26 | Eastman Kodak Co | New class of development promoter precursors for dry processing self-developing silver halide coatings |
US3042514A (en) * | 1959-08-06 | 1962-07-03 | Gen Aniline & Film Corp | Diffusion-transfer reversal process |
-
0
- NL NL256771D patent/NL256771A/xx unknown
- NL NL110284D patent/NL110284C/xx active
- BE BE609057D patent/BE609057A/xx unknown
-
1961
- 1961-10-10 US US147388A patent/US3257205A/en not_active Expired - Lifetime
- 1961-10-11 DE DE19611422887 patent/DE1422887A1/en active Pending
- 1961-10-11 CH CH1174261A patent/CH397734A/en unknown
- 1961-10-12 GB GB36699/61A patent/GB1001702A/en not_active Expired
Patent Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB670883A (en) * | 1949-06-21 | 1952-04-30 | Gevaert Photo Prod Nv | Improvements in or relating to the production of photographic images |
FR998055A (en) * | 1949-09-28 | 1952-01-14 | Gevaert Photo Prod Nv | Process for the production of photographic images |
DE1003578B (en) * | 1952-09-04 | 1957-02-28 | Zindler Lumoprint Kg | Process for producing photographic images and means for carrying out the same |
BE530883A (en) * | 1953-08-03 | 1957-10-25 | ||
US2751297A (en) * | 1953-08-03 | 1956-06-19 | Eastman Kodak Co | Photographic emulsion layer containing a 3-pyrazolidone |
US2751300A (en) * | 1954-07-15 | 1956-06-19 | Eastman Kodak Co | Photographic solvent transfer reproduction process |
US2971840A (en) * | 1955-02-07 | 1961-02-14 | Agfa Ag | Process for the production of nonlaterally reversed positive copies by heat development |
US3007795A (en) * | 1955-02-11 | 1961-11-07 | Agfa Ag | Process for the production of laterally non-reversed positive copies by heat development |
BE554934A (en) * | 1956-02-13 | 1900-01-01 | ||
US2891862A (en) * | 1956-11-06 | 1959-06-23 | Eastman Kodak Co | Stabilized photographic silver halide emulsions |
GB845928A (en) * | 1957-10-25 | 1960-08-24 | Ilford Ltd | Improvements in or relating to photographic emulsions |
US3015562A (en) * | 1958-05-07 | 1962-01-02 | Gen Aniline & Film Corp | Receiving sheet for use in photographic silver transfer process |
US3042514A (en) * | 1959-08-06 | 1962-07-03 | Gen Aniline & Film Corp | Diffusion-transfer reversal process |
US3041170A (en) * | 1959-10-29 | 1962-06-26 | Eastman Kodak Co | New class of development promoter precursors for dry processing self-developing silver halide coatings |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3352682A (en) * | 1963-09-13 | 1967-11-14 | Ilford Ltd | Photographic silver halide emulsion containing finely divided uinert particles dispersed in a synthetic colloid medium and a silver halide developer |
US3503741A (en) * | 1966-11-04 | 1970-03-31 | Eastman Kodak Co | Silver-dye-bleach process utilizing formazan dyes |
US3617289A (en) * | 1966-12-10 | 1971-11-02 | Fuji Photo Film Co Ltd | Stabilization process for thermally developable light-sensitive elements |
US3649158A (en) * | 1967-08-08 | 1972-03-14 | Oreal | Process for dyeing locks of human hair with tetragolium salts |
US3880659A (en) * | 1973-08-02 | 1975-04-29 | Eastman Kodak Co | Triazolium salt photoreductive imaging |
US4187108A (en) * | 1977-02-07 | 1980-02-05 | Eastman Kodak Company | Heat developable material and process |
Also Published As
Publication number | Publication date |
---|---|
CH397734A (en) | 1965-08-31 |
BE609057A (en) | |
DE1422887A1 (en) | 1968-11-28 |
NL256771A (en) | |
NL110284C (en) | |
GB1001702A (en) | 1965-08-18 |
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