US3099209A - Process of treating residual positive silver halide images with organic sulfur to render said images oleophilic - Google Patents
Process of treating residual positive silver halide images with organic sulfur to render said images oleophilic Download PDFInfo
- Publication number
- US3099209A US3099209A US11158A US1115860A US3099209A US 3099209 A US3099209 A US 3099209A US 11158 A US11158 A US 11158A US 1115860 A US1115860 A US 1115860A US 3099209 A US3099209 A US 3099209A
- Authority
- US
- United States
- Prior art keywords
- silver halide
- oleophilic
- images
- emulsion layer
- image
- 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
Links
- 229910052709 silver Inorganic materials 0.000 title claims description 40
- 239000004332 silver Substances 0.000 title claims description 40
- -1 silver halide Chemical class 0.000 title claims description 34
- 238000000034 method Methods 0.000 title description 20
- 125000001741 organic sulfur group Chemical group 0.000 title 1
- 239000000839 emulsion Substances 0.000 claims description 36
- 150000003573 thiols Chemical class 0.000 claims description 14
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 13
- 239000000976 ink Substances 0.000 claims description 12
- 239000012670 alkaline solution Substances 0.000 claims description 5
- WLHCBQAPPJAULW-UHFFFAOYSA-N 4-methylbenzenethiol Chemical compound CC1=CC=C(S)C=C1 WLHCBQAPPJAULW-UHFFFAOYSA-N 0.000 claims description 4
- 230000015572 biosynthetic process Effects 0.000 claims description 3
- YHMYGUUIMTVXNW-UHFFFAOYSA-N 1,3-dihydrobenzimidazole-2-thione Chemical compound C1=CC=C2NC(S)=NC2=C1 YHMYGUUIMTVXNW-UHFFFAOYSA-N 0.000 claims 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims 1
- 229910052700 potassium Inorganic materials 0.000 claims 1
- 239000011591 potassium Substances 0.000 claims 1
- 229940009188 silver Drugs 0.000 description 36
- 239000000243 solution Substances 0.000 description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 8
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 6
- 229910052782 aluminium Inorganic materials 0.000 description 6
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 5
- 239000000084 colloidal system Substances 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- 150000002898 organic sulfur compounds Chemical class 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- KXDAEFPNCMNJSK-UHFFFAOYSA-N Benzamide Chemical compound NC(=O)C1=CC=CC=C1 KXDAEFPNCMNJSK-UHFFFAOYSA-N 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 230000020477 pH reduction Effects 0.000 description 2
- OMKVZYFAGQKILB-UHFFFAOYSA-M potassium;butoxymethanedithioate Chemical compound [K+].CCCCOC([S-])=S OMKVZYFAGQKILB-UHFFFAOYSA-M 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- DKKMQUFRNJJBAS-UHFFFAOYSA-N 1-(ethylamino)ethanethiol Chemical compound CCNC(C)S DKKMQUFRNJJBAS-UHFFFAOYSA-N 0.000 description 1
- YAJYJWXEWKRTPO-UHFFFAOYSA-N 2,3,3,4,4,5-hexamethylhexane-2-thiol Chemical compound CC(C)C(C)(C)C(C)(C)C(C)(C)S YAJYJWXEWKRTPO-UHFFFAOYSA-N 0.000 description 1
- UCJMHYXRQZYNNL-UHFFFAOYSA-N 2-Ethyl-1-hexanethiol Chemical compound CCCCC(CC)CS UCJMHYXRQZYNNL-UHFFFAOYSA-N 0.000 description 1
- JKFYKCYQEWQPTM-UHFFFAOYSA-N 2-azaniumyl-2-(4-fluorophenyl)acetate Chemical compound OC(=O)C(N)C1=CC=C(F)C=C1 JKFYKCYQEWQPTM-UHFFFAOYSA-N 0.000 description 1
- DQFBYFPFKXHELB-UHFFFAOYSA-N Chalcone Natural products C=1C=CC=CC=1C(=O)C=CC1=CC=CC=C1 DQFBYFPFKXHELB-UHFFFAOYSA-N 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- XZMCDFZZKTWFGF-UHFFFAOYSA-N Cyanamide Chemical compound NC#N XZMCDFZZKTWFGF-UHFFFAOYSA-N 0.000 description 1
- 108010010803 Gelatin Proteins 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 229910021607 Silver chloride Inorganic materials 0.000 description 1
- 229910021612 Silver iodide Inorganic materials 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 229920002494 Zein Polymers 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- YKTSYUJCYHOUJP-UHFFFAOYSA-N [O--].[Al+3].[Al+3].[O-][Si]([O-])([O-])[O-] Chemical compound [O--].[Al+3].[Al+3].[O-][Si]([O-])([O-])[O-] YKTSYUJCYHOUJP-UHFFFAOYSA-N 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 238000003287 bathing Methods 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 235000005513 chalcones Nutrition 0.000 description 1
- UFULAYFCSOUIOV-UHFFFAOYSA-N cysteamine Chemical compound NCCS UFULAYFCSOUIOV-UHFFFAOYSA-N 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 150000002019 disulfides Chemical class 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 229920000159 gelatin Polymers 0.000 description 1
- 239000008273 gelatin Substances 0.000 description 1
- 235000019322 gelatine Nutrition 0.000 description 1
- 235000011852 gelatine desserts Nutrition 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 230000005660 hydrophilic surface Effects 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- 239000004848 polyfunctional curative Substances 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 229920001290 polyvinyl ester Polymers 0.000 description 1
- 230000001235 sensitizing effect Effects 0.000 description 1
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical compound [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 description 1
- 229940100890 silver compound Drugs 0.000 description 1
- 150000003379 silver compounds Chemical class 0.000 description 1
- 229940045105 silver iodide Drugs 0.000 description 1
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 150000003464 sulfur compounds Chemical class 0.000 description 1
- DQFBYFPFKXHELB-VAWYXSNFSA-N trans-chalcone Chemical compound C=1C=CC=CC=1C(=O)\C=C\C1=CC=CC=C1 DQFBYFPFKXHELB-VAWYXSNFSA-N 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000000080 wetting agent Substances 0.000 description 1
- 239000005019 zein Substances 0.000 description 1
- 229940093612 zein Drugs 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
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/004—Photosensitive materials
- G03F7/06—Silver salts
- G03F7/063—Additives or means to improve the lithographic properties; Processing solutions characterised by such additives; Treatment after development or transfer, e.g. finishing, washing; Correction or deletion fluids
- G03F7/066—Organic derivatives of bivalent sulfur, e.g. onium derivatives
Definitions
- the printing plate comprises a support coated with a colloid carrier which when wet is hydrophilic and carries a line or dot image which is oleophilic.
- the oleophilic properties of the image and hydrophilic properties of the surrounding support surface are relative in nature to some extent.
- both ink and water are applied and the colloid coated on the support is sufiiciently hydrophilic to accept water but not the greasy ink, while the image accepts the ink but not the water.
- the difference in hydrophilic and oleophilic properties of the image and the back ground surface is sufficiently great that when water and ink are applied, the image will accept suflicient ink without the background accepting any ink at all.
- lithographic printing plates are supports the nature of whose surface is such that when wetted with water will not accept greasy ink.
- the practice in making a photolithographic printing plate is to produce an oleophilic image on the hydrophilic support which can be put into an inking machine whereby large numbers of copies can usually be made very rapidly from the one plate.
- Aluminum sheet employed in the art is provided with an inert hydrophilic surface. This is often done by treating the aluminum to produce thereon an aluminum compound which is hydrophilic for instance, aluminum oxide as in the case of anodised aluminum, aluminum silicate and chromati zed aluminum.
- a printing process employing greasy ink on metal plates was suggested many years ago by K. W. C. Webb in which an image formed of silver halide or silver and mercury was brought into contact with a smooth metal surface such as a polished copper plate in the presence of certain deposition agents.
- the plates used in that suggested process for instance the polished copper plate, were not as such suitable as lithographic printing plates and it was necessary to etch the bare copper parts after the image had been formed.
- One object of the present invention is to provide a process which entirely avoids etching after formation of the image by making the image areas very oleophilic compared with the background areas.
- an object of the present invention is to provide a process which satisfies these requirements in a very surprisingly simple way by merely forming a negative silver image in a silver halide emulsion layer and treating the residual positive silver halide image in the presence of the silver negative image with solutions of certain organic sulfur compounds which react with the silver halide positive image in the emulsion layer to render it oleophilic whereas the hydrophilic property of the silver negative image in the emulsion layer is not appreciably affected.
- This treatment of the silver'halide positive image areas of the emulsion with the solutions of the sulfur compounds can very easily be done by swabbing the emulsion layer with the solution, bathing the emulsion layer in the solution for a short time or otherwise applying the solution to the emulsion layer in any convenient manner to render the residual silver halide oleophilic and the emulsion surface thus ink-receptive in that region.
- the organic sulfur compounds which can be used as described alone or in combination are the following thiols Lmercaptobenzothiazole
- the above thiol compounds are further characterized by forming with the silver halide, an oleophilic silver compound more insoluble in water than the silver halide used, thus the thiols will not wash out of the emulsion layer if a washing step is used in the process or during the normal treatment of the oleophilic image with water and greasy ink.
- Adducts and unsaturated derivatives, e.g. cyanamid, chalcone or disulfide derivatives of the above thiol compounds which hydrolyze in alkaline solution to yield the above thiol compounds and no other photographically active species act as donors, in situ, of the above thiols.
- These thiol donors can be present either directly in the emulsion layer or in a layer contiguous to it.
- the thiol donors can also be present in the emulsion together with an alkaline developer composition so that when the element is exposed and then subjected to moisture or heat, or both, in the presence of the alkali, the developer composition develops the latent silver negative image to a visible image while the thiol donor simultaneously splits to release a thiol of our invention which reacts with the residual silver halide positive image to render it oleophilic and capable ofacting as alithographic plate.
- the compound S-nitroindazole can be used in a similar manner to obtain an elecphilic image in the region of a silver halide positive image.
- Many organic sulfur compounds are inactive or do not react at the surface of emulsion layers in the region of the silver halide positive image in the presence of a silver negative image and may react only in the region of the silver image or render the entire emulsion surface more or less oleophilic, e.g. the following are representative of a large number which have been found to be inactive in our invention in that they did not render silver halide oleophilic:
- our invention contemplates the preparation and use of a lithographic printing plate prepared by treating a developed but unfixed silver halide emulsion layer, such as a gelatin-silver halide emulsion layer containing a silver negative image and residual silver halide positive image, with the mentioned compounds alone or in combination so as to render the surface of the emulsion layer oleophilic only in the region of the silver halide positive image with the result that upon subsequent acidification of the emulsion layer and inking, lithographic prints can be made in the usual manner.
- a developed but unfixed silver halide emulsion layer such as a gelatin-silver halide emulsion layer containing a silver negative image and residual silver halide positive image
- a photographic paper having a contact speed gelatinsil'ver chloride emulsion was exposed to a graphic subject (line or halftone subject), then developed for 30 seconds at 70-75 F. in a conventional Elon-hydroquinone photographic paper developer solution after which it was removed from the developing bath and squeegeed.
- the surface was then treated for 10 to 20 seconds with a percent solution of p-toluenethiol dissolved in 5 percent sodium hydroxide solution.
- the surface thus treated was rinsed, acidified with 5 percent acetic acid solution and placed on a Multilith printing press.
- the undeveloped areas of the emulsion were found to be oleophilic and printed a positive image, the p-toluenethiol presumably being reactive with the undeveloped silver halide to form an oleophiliic surface.
- the emulsion may then be acidified with dilute acid solution to stop development and after a brief wash of about 2 minutes in running water, treated with the alkaline solution of the thiol compound.
- the subsequent acidification step may be carried out in a convenient manner, for example, by application of dilute acetic acid solution or other acid fountain solution on the printing press.
- the hydrophilic organic colloid of the silver halide emulsion layers used in the invention is not especially critical and may include gelatin, colloidal albumen, zein, partially hydrolyzed cellulose esters, polyvinyl alcohol, partially hydrolyzed polyvinyl ester, po lyacrylamide, and other hydrophilic naturally occurring and synthetic organic colloids.
- the silver halide emulsions may be selected from well-known emulsions containing silver chloride, silver bromide and silver iodide or mixtures thereof as well as containing optical and chemical sensitizing agents, fog-stabilizing compounds, emulsion hardeners, pl asticizing compounds and wetting agents.
- a lithographic printing process which comprises reacting the residual silver halide remaining after formation of a developed silver image in the emulsion layer with an alkaline solution of a thiol selected from the group consisting of p-toluenethiol, potassium n-butyl xanthate, Z-mercapto-S-phenyl-1,3,4-oxadiazole, Z-mercaptobenzothiazole, Z-mercaptobenzimidazole and 2-ethyl-hexanethiol until the surface of the moist emulsion layer in only the region of the undeveloped silver halide has become receptive to greasy inks, acidifying the emu sion layer, inking the moist emulsion layer and printing a lithographic print therefrom.
- a thiol selected from the group consisting of p-toluenethiol, potassium n-butyl xanthate, Z-mercapto-S-phenyl
- the emulsion layer is a gelatin-silver halide emulsion layer.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Photosensitive Polymer And Photoresist Processing (AREA)
- Printing Plates And Materials Therefor (AREA)
Description
United States Patent 3,099,209 PROCESS OF TREATING RESIDUAL POSITIVE SIL- VER I-IALIDE IMAGES WITH ORGANIC SULFUR T0 RENDER SAID IMAGES OLEOPHILIC Rudolph E. Damschroder and Edward C. Yackel, Rochester, N.Y., assignors to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey No Drawing. Filed Feb. 26, 1960, Ser. No. 11,158 7 Claims. (Cl. 101-1492) This invention relates to a lithographic printing process and more particularly to a photographic method for the preparation of lithographic printing plates.
In lithography a greasy ink is employed and the printing plate comprises a support coated with a colloid carrier which when wet is hydrophilic and carries a line or dot image which is oleophilic.
The oleophilic properties of the image and hydrophilic properties of the surrounding support surface are relative in nature to some extent. When using an image bearing plate for printing, both ink and water are applied and the colloid coated on the support is sufiiciently hydrophilic to accept water but not the greasy ink, while the image accepts the ink but not the water. Hence, to obtain good prints it is necessary that the difference in hydrophilic and oleophilic properties of the image and the back ground surface is sufficiently great that when water and ink are applied, the image will accept suflicient ink without the background accepting any ink at all. Hence, lithographic printing plates are supports the nature of whose surface is such that when wetted with water will not accept greasy ink.
The practice in making a photolithographic printing plate is to produce an oleophilic image on the hydrophilic support which can be put into an inking machine whereby large numbers of copies can usually be made very rapidly from the one plate.
' Where only a few hundreds of copies are required, or even up to about a thousand copies, it is quite common to use a paper type printing plate, but where many thousands of copies are required it is necessary to use a more substantial type of printing plate and the ones commonly used are made of aluminum sheet or zinc sheet. From these metal sheets it is a common practice in the art to take as many as twenty thousand copies. Aluminum sheet employed in the art is provided with an inert hydrophilic surface. This is often done by treating the aluminum to produce thereon an aluminum compound which is hydrophilic for instance, aluminum oxide as in the case of anodised aluminum, aluminum silicate and chromati zed aluminum.
When making such printing plates, usually an ordinary negative is first made and then this is used for making a positive oleophilic image on the printing plate. A large number of processes have been used and suggested for doing this.
A printing process employing greasy ink on metal plates was suggested many years ago by K. W. C. Webb in which an image formed of silver halide or silver and mercury was brought into contact with a smooth metal surface such as a polished copper plate in the presence of certain deposition agents. The plates used in that suggested process, for instance the polished copper plate, were not as such suitable as lithographic printing plates and it was necessary to etch the bare copper parts after the image had been formed. One object of the present invention is to provide a process which entirely avoids etching after formation of the image by making the image areas very oleophilic compared with the background areas.
In view of the wide variety of commercial uses of 3,099,209 Patented July 30, 1 963 "ice photolithographic copying, it is very desirable to have a process which is both simple and efiective.
'An object of the present invention is to provide a process which satisfies these requirements in a very surprisingly simple way by merely forming a negative silver image in a silver halide emulsion layer and treating the residual positive silver halide image in the presence of the silver negative image with solutions of certain organic sulfur compounds which react with the silver halide positive image in the emulsion layer to render it oleophilic whereas the hydrophilic property of the silver negative image in the emulsion layer is not appreciably affected. This treatment of the silver'halide positive image areas of the emulsion with the solutions of the sulfur compounds can very easily be done by swabbing the emulsion layer with the solution, bathing the emulsion layer in the solution for a short time or otherwise applying the solution to the emulsion layer in any convenient manner to render the residual silver halide oleophilic and the emulsion surface thus ink-receptive in that region.
The organic sulfur compounds which can be used as described alone or in combination are the following thiols Lmercaptobenzothiazole The above thiol compounds are further characterized by forming with the silver halide, an oleophilic silver compound more insoluble in water than the silver halide used, thus the thiols will not wash out of the emulsion layer if a washing step is used in the process or during the normal treatment of the oleophilic image with water and greasy ink. v
Adducts and unsaturated derivatives, e.g. cyanamid, chalcone or disulfide derivatives of the above thiol compounds which hydrolyze in alkaline solution to yield the above thiol compounds and no other photographically active species act as donors, in situ, of the above thiols. These thiol donors can be present either directly in the emulsion layer or in a layer contiguous to it. The thiol donors can also be present in the emulsion together with an alkaline developer composition so that when the element is exposed and then subjected to moisture or heat, or both, in the presence of the alkali, the developer composition develops the latent silver negative image to a visible image while the thiol donor simultaneously splits to release a thiol of our invention which reacts with the residual silver halide positive image to render it oleophilic and capable ofacting as alithographic plate.
It is interesting to note that the compound S-nitroindazole can be used in a similar manner to obtain an elecphilic image in the region of a silver halide positive image. Many organic sulfur compounds are inactive or do not react at the surface of emulsion layers in the region of the silver halide positive image in the presence of a silver negative image and may react only in the region of the silver image or render the entire emulsion surface more or less oleophilic, e.g. the following are representative of a large number which have been found to be inactive in our invention in that they did not render silver halide oleophilic:
a,o-Dimercapto adipic acid 2,5 -dimercapto 1,3 ,4-thiadiazole B-Mercapto ethyl amine HCl Di ethylaminoethanethiol HCl B-Carboxymethylmercaptobenzalacetophenone The following organic sulfur compounds were found to be unacceptable in that while they imparted some degree of oleophilictivity to the emulsion surface, they failed to differentiate between the silver negative image and the silver halide positive image:
Thiosalicycl-ic acid l-phenyl-S-mercapto tetrazole Z-mercapto-6-nitrobenzothiazole N-Methyl-2-rnercapto benzamide Biphenyl-4,4'-dithiol t-Dodecylmercaptan benzamide Accordingly, our invention contemplates the preparation and use of a lithographic printing plate prepared by treating a developed but unfixed silver halide emulsion layer, such as a gelatin-silver halide emulsion layer containing a silver negative image and residual silver halide positive image, with the mentioned compounds alone or in combination so as to render the surface of the emulsion layer oleophilic only in the region of the silver halide positive image with the result that upon subsequent acidification of the emulsion layer and inking, lithographic prints can be made in the usual manner.
The fiollowing example will serve to illustrate the process of our invention:
A photographic paper having a contact speed gelatinsil'ver chloride emulsion was exposed to a graphic subject (line or halftone subject), then developed for 30 seconds at 70-75 F. in a conventional Elon-hydroquinone photographic paper developer solution after which it was removed from the developing bath and squeegeed. The surface was then treated for 10 to 20 seconds with a percent solution of p-toluenethiol dissolved in 5 percent sodium hydroxide solution. The surface thus treated was rinsed, acidified with 5 percent acetic acid solution and placed on a Multilith printing press. The undeveloped areas of the emulsion were found to be oleophilic and printed a positive image, the p-toluenethiol presumably being reactive with the undeveloped silver halide to form an oleophiliic surface.
When alkaline solutions of the other effective thiol compounds mentioned were used in a similar manner for treating a developed silver halide emulsion layer, the surface became oleophilic in the region of the undeveloped silver halide and printed readily in a lithographic printing press.
In the process of the invention illustrated above, after development of the emulsion in the conventional manner, the emulsion may then be acidified with dilute acid solution to stop development and after a brief wash of about 2 minutes in running water, treated with the alkaline solution of the thiol compound. The subsequent acidification step may be carried out in a convenient manner, for example, by application of dilute acetic acid solution or other acid fountain solution on the printing press.
The hydrophilic organic colloid of the silver halide emulsion layers used in the invention is not especially critical and may include gelatin, colloidal albumen, zein, partially hydrolyzed cellulose esters, polyvinyl alcohol, partially hydrolyzed polyvinyl ester, po lyacrylamide, and other hydrophilic naturally occurring and synthetic organic colloids. Similarly, the silver halide emulsions may be selected from well-known emulsions containing silver chloride, silver bromide and silver iodide or mixtures thereof as well as containing optical and chemical sensitizing agents, fog-stabilizing compounds, emulsion hardeners, pl asticizing compounds and wetting agents.
We claim:
. l. A lithographic printing process which comprises reacting the residual silver halide remaining after formation of a developed silver image in the emulsion layer with an alkaline solution of a thiol selected from the group consisting of p-toluenethiol, potassium n-butyl xanthate, Z-mercapto-S-phenyl-1,3,4-oxadiazole, Z-mercaptobenzothiazole, Z-mercaptobenzimidazole and 2-ethyl-hexanethiol until the surface of the moist emulsion layer in only the region of the undeveloped silver halide has become receptive to greasy inks, acidifying the emu sion layer, inking the moist emulsion layer and printing a lithographic print therefrom.
2. The process of claim 1 wherein the emulsion layer is a gelatin-silver halide emulsion layer.
3. The process of claim 1 wherein the thiol used is ptoluenethiol.
4. The process of claim 1 wherein the thiol used is potassium n-butyl xanthate.
5. The process of claim 1 wherein the thiol used is Z-mercapto-S-phenyi-1,3,4-oxadiazole.
6. The process of claim 1 wherein the thiol used is Z-mercaptobenzothiazole.
7. The process of claim 1 wherein the thiol used is Z-mercaptobenzimidazole.
References Cited in the file of this patent UNITED STATES PATENTS 2,453,346 Russell Nov. 9, 1948 2,843,491 Allen et a1. July 15, 1958 FOREIGN PATENTS 1,058,844 Germany June 4, 1959 1,064,343 Germany Aug. 27, 1959 1,064,807 Germany Sept. 3, 1959 758,759 Great Britain Oct. 10, 1956
Claims (1)
1. A LITHOGRAPHIC PRINTING PROCEESS WHICH COMPRISES REACTING THE RESIDUAL SILVER HALIDE REMAINING AFTER FORMATION OF A DEVELOPED SILVER IMAGE IN THE EMULSION LAYER WITH AN ALKALINE SOLUTION OF A THIOL SELECTED FROM THE GROUP CONSISTING OF P-TOLUENETHIOL, POTASSIUM N-BUTYL ZANTHATE, 2-MERCAPTO-5-PHENYL-1,3,4,-OXIDIAZOLE, 2-MERCAPTOBENZOTHIAZLE, 2-MERCAPTOBENZIMIDAZOLE AND 2-ETHYL-HEZANETHIOL UNTIL THE SURFACE OF THE MOIST EMULSION LAYER IN ONLY THE REGION OF THE UNDEVELOPED SILVER HALIDE HAS BECOME RECEPTIVE TO GREASY INKS, ACIDIFYING THE EMULSION LAYER, INKING THE MOIST EMULSION LAYER AND PRINTING A LITHOGRAPHIC PRINT THEREFROM.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US11158A US3099209A (en) | 1960-02-26 | 1960-02-26 | Process of treating residual positive silver halide images with organic sulfur to render said images oleophilic |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US11158A US3099209A (en) | 1960-02-26 | 1960-02-26 | Process of treating residual positive silver halide images with organic sulfur to render said images oleophilic |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3099209A true US3099209A (en) | 1963-07-30 |
Family
ID=21749118
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US11158A Expired - Lifetime US3099209A (en) | 1960-02-26 | 1960-02-26 | Process of treating residual positive silver halide images with organic sulfur to render said images oleophilic |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3099209A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3326684A (en) * | 1962-04-06 | 1967-06-20 | Fuji Photo Film Co Ltd | Method for stabilizing developed photosensitive materials |
| US3454398A (en) * | 1966-08-29 | 1969-07-08 | American Photocopy Equip Co | Method of forming a lithographic plate by treating silver halide with a terminal ethynyl compound to form an ink receptive image area |
| US3620737A (en) * | 1968-08-09 | 1971-11-16 | Eastman Kodak Co | Etching of differentially hardened plates by enzymes |
| DE2507700A1 (en) * | 1974-02-26 | 1975-08-28 | Agfa Gevaert Ag | METHOD OF MANUFACTURING A FLAT PRINT PLATE WITH A PHOTOGRAPHIC SILVER HALOGENIDE MATERIAL |
| US4230792A (en) * | 1976-07-15 | 1980-10-28 | Mitsubishi Paper Mills, Ltd. | Lithographic printing plate from silver halide emulsion |
| US4567131A (en) * | 1983-07-11 | 1986-01-28 | Vickers Plc | Lithographic printing plates |
| EP0330215A3 (en) * | 1988-02-25 | 1990-04-04 | Mitsubishi Paper Mills, Ltd. | Method for making lithographic printing plate |
| US5198324A (en) * | 1988-12-08 | 1993-03-30 | Mitsubishi Paper Mills Limited | Method for making lithographic printing plate |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2453346A (en) * | 1945-10-25 | 1948-11-09 | Eastman Kodak Co | Stabilization of processed photographic emulsions to high temperatures and humidities |
| GB758759A (en) * | 1953-03-24 | 1956-10-10 | Agfa Ag | Process for the production of stable photographic silver images by the silver salt diffusion process |
| US2843491A (en) * | 1956-05-23 | 1958-07-15 | Eastman Kodak Co | 2-mercapto-1, 3, 4-oxadiazoles as antifoggants |
| DE1058844B (en) * | 1957-04-26 | 1959-06-04 | Agfa Ag | Process for the production of planographic printing plates by photographic means |
| DE1064807B (en) * | 1958-03-31 | 1959-09-03 | Eastman Kodak Co | Silver salt photographic diffusion transfer process |
-
1960
- 1960-02-26 US US11158A patent/US3099209A/en not_active Expired - Lifetime
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2453346A (en) * | 1945-10-25 | 1948-11-09 | Eastman Kodak Co | Stabilization of processed photographic emulsions to high temperatures and humidities |
| GB758759A (en) * | 1953-03-24 | 1956-10-10 | Agfa Ag | Process for the production of stable photographic silver images by the silver salt diffusion process |
| US2843491A (en) * | 1956-05-23 | 1958-07-15 | Eastman Kodak Co | 2-mercapto-1, 3, 4-oxadiazoles as antifoggants |
| DE1058844B (en) * | 1957-04-26 | 1959-06-04 | Agfa Ag | Process for the production of planographic printing plates by photographic means |
| DE1064343B (en) * | 1957-04-26 | 1959-08-27 | Agfa Ag | Process for improving the adhesion of bold printing inks to silver photographic images |
| DE1064807B (en) * | 1958-03-31 | 1959-09-03 | Eastman Kodak Co | Silver salt photographic diffusion transfer process |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3326684A (en) * | 1962-04-06 | 1967-06-20 | Fuji Photo Film Co Ltd | Method for stabilizing developed photosensitive materials |
| US3454398A (en) * | 1966-08-29 | 1969-07-08 | American Photocopy Equip Co | Method of forming a lithographic plate by treating silver halide with a terminal ethynyl compound to form an ink receptive image area |
| US3620737A (en) * | 1968-08-09 | 1971-11-16 | Eastman Kodak Co | Etching of differentially hardened plates by enzymes |
| DE2507700A1 (en) * | 1974-02-26 | 1975-08-28 | Agfa Gevaert Ag | METHOD OF MANUFACTURING A FLAT PRINT PLATE WITH A PHOTOGRAPHIC SILVER HALOGENIDE MATERIAL |
| US4230792A (en) * | 1976-07-15 | 1980-10-28 | Mitsubishi Paper Mills, Ltd. | Lithographic printing plate from silver halide emulsion |
| US4567131A (en) * | 1983-07-11 | 1986-01-28 | Vickers Plc | Lithographic printing plates |
| EP0131462A3 (en) * | 1983-07-11 | 1986-09-17 | Vickers Plc | Improvements in or relating to lithographic printing plates |
| EP0330215A3 (en) * | 1988-02-25 | 1990-04-04 | Mitsubishi Paper Mills, Ltd. | Method for making lithographic printing plate |
| US5064745A (en) * | 1988-02-25 | 1991-11-12 | Mitsubishi Paper Mills, Ltd. | Method for making lithographic printing plate |
| US5198324A (en) * | 1988-12-08 | 1993-03-30 | Mitsubishi Paper Mills Limited | Method for making lithographic printing plate |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US2596756A (en) | Photomechanical copy method | |
| US2716059A (en) | Photographic transfer process | |
| US2740717A (en) | Photographic transfer process | |
| US3146104A (en) | Silver halide sensitized lithographic printing plate | |
| US3161508A (en) | Process of lithographic printing | |
| US4230792A (en) | Lithographic printing plate from silver halide emulsion | |
| US2614927A (en) | Rapid processing of photographic materials | |
| US3364024A (en) | Photographic process | |
| US3099209A (en) | Process of treating residual positive silver halide images with organic sulfur to render said images oleophilic | |
| US3046131A (en) | Photographic material containing light sensitive quinone diazides | |
| US2772160A (en) | Light-detached resists or reliefs for printing plates | |
| US2843485A (en) | Transfer process of photographic printing | |
| US2058396A (en) | Photoink printing | |
| US3511656A (en) | Single sheet lithographic dtr master and method of use | |
| US2835575A (en) | Photographic reproduction process | |
| US3490905A (en) | Process for making printing plates | |
| US3625687A (en) | Process for making negative working offset masters containing thin gelatin relief images | |
| US3385701A (en) | Lithographic offset master and method | |
| US3561961A (en) | Photosensitive lithographic printing master and process for preparation of a lithographic plate | |
| US2969014A (en) | Photochemical stencil and method for manufacture | |
| US3369902A (en) | Lithographic plates sensitized with oxacarbocyanine and benzimidazole carbocyanine dyes | |
| US3067033A (en) | Production of transfer images by the silver salt diffusion process | |
| US3592647A (en) | Process for improving planographic offset printing plates | |
| US2739890A (en) | Photographic reproduction process | |
| US3914125A (en) | Diffusion transfer element and method of using same |