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
  • G03C1/52—Compositions containing diazo compounds as photosensitive substances
  • G03C1/60—Compositions containing diazo compounds as photosensitive substances with macromolecular additives
• • 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
  • G03C1/76—Photosensitive materials characterised by the base or auxiliary layers
  • G03C1/775—Photosensitive materials characterised by the base or auxiliary layers the base being of paper
• • 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
  • G03C1/76—Photosensitive materials characterised by the base or auxiliary layers
  • G03C1/95—Photosensitive materials characterised by the base or auxiliary layers rendered opaque or writable, e.g. with inert particulate additives

Definitions

• the present invention relates to a photographic sheet material and method for its preparation. It has particular application to sheet material which is especially suitable for photographic reproduction, particularly by the diazotype process, although it may be applied as well to other types of photographically sensitized material.
• coated sheet materials which are designed or intended for photographic work and which have surfaces which are well adapted for development of dye images and which lend themselves to erasure and modification of the photographic material.
• Sheets of cloth, textile, paper, film base, etc., for this purpose, particularly paper sheets, are ordinarily sized and/ or coated with suitable pigment materials of various types. These pigments are secured to the base sheet by an appropriate resinous binder.
• precoating materials including pigments alone, binders alone, and combinations, have been used for photographic purposes and, more specifically, for diazotype coatings of sheet materials. These coating materials generally contribute to surface smoothness and they tend to improve the dye density, especially when images are developed from dye formers such as diazonium compounds.
• Pigments commonly used in diazotype precoatings include silicas, starches, aluminas, alumino-silicates, and synthetic polymeric particles. Binders commonly employed include such materials as sodium caseinate, kelgin, water-soluble cellulosic resins, paper sizing glues, and the like. Synthetic aqueous polyvinyl dispersions such as polyvinylacetate, polystyrene and various acrylate and methacrylates may be used. These materials, when not water soluble, are preferably applied for precoating purposes in the form of water emulsions. The emulsions are, of course, desirable for compatibility with the photosensitive materials to be applied later.
• the precoating is applied to the suitable base which may be paper, cloth or even film base. Ordinarily, paper is preferred for diazotype reproduction sheets and the following discussion relates mainly to its use. This precoating is applied to the base sheet prior to application of the sensitizing solution.
• the paper can be coated either by the diazotype manufacturer or, if desired, by the mill which fabricates the paper or cloth base.
• the pigment component of the precoat is advantageous to intensify the dye, as the latter is developed.
• the pigment materials most often used are too easily removed unless substantial quantities of binder are used. They are particularly subject to being rubbed off or to cracking or to crocking on handling the sheet material. If too much binder is employed in an eifort to more securely fasten the pigment to the base sheet, this tends to submerge the pigment, keep it somewhat out of contact with the image-forming dye materials, and thus tends to reduce the dye density which the pigment is intended to improve.
• a pigment-binder ratio which gives an optimum dye density when subsequently sensitized and printed or developed, may exhibit too great a tendency to rubbing off of the pigment or to crocking. If the proportion of binder is increased sufficiently to offset this tendency, then the dye density may be reduced to an objectionable degree.
• binder materials such as polyvinylacetate emulsions which are often used as precoat, or part of the precoat, tend to become tacky during processing of the print. In such cases, the sheets tend to stick or adhere to machine parts in the developing section of the equipment, causing difficulty in mechanical handling of the sheets and causing damage to the photographic surface.
• hydrocarbon waxes, rosins, rosin-wax mixtures and hydrocarbon polymeric materials such as polyethylene, polypropylene and the like may be employed. Mixtures of any two or more of these also may be used. Paraffin waxes, combinations of rosin and parafiin wax, and polyethylene are particularly preferred.
• These emulsions may also be used as components of the diazotype sensitizing solution if desired. However, their effectiveness is better when they are used in the precoat layer. When properly used, these hydrophobic emulsions of waxy material reduce the precoat pigment rub-off or crocking substantially. They also reduce the tackiness of the film-forming materials which are used as binders or as precoats. They reduce the tendency for the resinous binder to take up the dye and reduce dye density. At the same time, they do not interfere with the dyes or their development.
• Example I A paper base sheet material was coated uniformly with a precoating material consisting of the following:
• Example II A paper base material was uniformly coated with the following precoating material:
• Example II 2 parts by weight of 4-dimethylaminobenzenediazonium chlorozincate parts by weight of zinc chloride 3 parts by weight of sodium 6-7-dihydroxynaphthalene- 2-sulfonate 5 parts by weight of citric acid 4 parts by weight of thiourea 5 parts by weight of ethylene glycol 100 parts by weight of water
• the sensitized paper was dried and exposed to light under a translucent original as in the case of Example I. Development was obtained by exposing the sheet to aqueous ammonia vapors. A bright, blue-line print of high density resulted, as in Example I, which also resisted pigment rub-off much better than a similar print made from the same precoating, leaving out the polyethylene emulsion.
• Example III Paper base material was uniformly coated with the following precoated material:
• Example IV A paper base sheet was uniformly coated with a composition as follows: 50 parts by weight of polyvinylacetate emulsion 4 parts by weight of paraflin wax emulsion 50 parts by weight of water This precoated paper was dried and sensitized with the following composition:
• Example V Paper base material was coated uniformlywith a precoating material of the following composition:
• a further aspect of my invention is to eliminate these two objections by placing a backwash of the wax emulsion in an amount of 2 to 20% by weight of the wax in the emulsion. Similarly, curl will be eliminated by precoating and sensitizing both surfaces of the paper while utilizing the compositions of any of the examples.
• the pigment which is employed is of the nature of a white opacifying pigment such as is typified by silica, alumina and the like.
• these diazos are used in the form of their salts stabilized with zinc chloride, tin chloride, cadmium chloride and the like.
• couplers other than those mentioned in the examples, are 2,5-xylenol; 2,3-dihydroxy naphthalene; resorcinol, octyl-resorcinol; p-methyl-N-phenyl pyrazolone; the amide of a-resorcylic acid; 2-hydroxynaphthalene-3,6-disulfonic acid; H acid; acetyl acetanilide; 2,3- dihydroxynaphthalene-G-sulfonic acid; a-resorcylic acid and the like.
• a non-tacky photographic sheet comprising a base support sheet, carrying in that order a precoat which includes a white opacifying pigment, a resinous binder, and
• precoat carrying a photosensitive diazotype layer.
• an emulsified hydrophobic solid material of waxy consistency selected from the group consisting of parafiin wax, rosin, the mixture of rosin and paraffin wax, water-insoluble polyethylene and water insoluble polypropylene, said precoat carrying a photosensitive diazotype layer.
• both surfaces of the base sheet are carrying said precoat, one of said precoats carrying a photosensitive layer containing a diazonium compound and a coupling component.
• a sheet according to claim 1 wherein the emulsified hydrophobic material is an emulsified water-insoluble polyethylene.
• a sheet according to claim 1 wherein the emulsified hydrophobic material is a rosin emulsion.
• a sheet according to claim 1 wherein the emulsified hydrophobic material is the mixture of a paraflin wax and rosin.

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• Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• General Physics & Mathematics (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Paper (AREA)
• Heat Sensitive Colour Forming Recording (AREA)
• Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)

Priority Applications (8)

Applications Claiming Priority (1)

Publications (1)

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Cited By (1)

Citations (8)

• 1963
  • 1963-03-19 US US266176A patent/US3276876A/en not_active Expired - Lifetime
• 1964
  • 1964-02-27 CH CH244764A patent/CH443896A/de unknown
  • 1964-03-02 GB GB8674/64A patent/GB1046294A/en not_active Expired
  • 1964-03-07 DE DE19641447687 patent/DE1447687A1/de active Pending
  • 1964-03-19 BE BE645409D patent/BE645409A/xx unknown
  • 1964-03-19 FR FR967893A patent/FR1386055A/fr not_active Expired

Patent Citations (8)

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