Classifications

• • A—HUMAN NECESSITIES
  • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
  • A23B—PRESERVATION OF FOODS, FOODSTUFFS OR NON-ALCOHOLIC BEVERAGES; CHEMICAL RIPENING OF FRUIT OR VEGETABLES
  • A23B4/00—Preservation of meat, sausages, fish or fish products
  • A23B4/06—Freezing; Subsequent thawing; Cooling
  • A23B4/066—Freezing; Subsequent thawing; Cooling the materials not being transported through or in the apparatus with or without shaping, e.g. in the form of powder, granules or flakes
  • A23B4/068—Freezing; Subsequent thawing; Cooling the materials not being transported through or in the apparatus with or without shaping, e.g. in the form of powder, granules or flakes with packages or with shaping in the form of blocks or portions
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
  • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
  • D21H21/30—Luminescent or fluorescent substances, e.g. for optical bleaching
• • 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
  • G03C1/815—Photosensitive materials characterised by the base or auxiliary layers characterised by means for filtering or absorbing ultraviolet light, e.g. optical bleaching
  • G03C1/8155—Organic compounds therefor
• • 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
  • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
  • G03C5/26—Processes using silver-salt-containing photosensitive materials or agents therefor
  • G03C5/29—Development processes or agents therefor
  • G03C5/305—Additives other than developers
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
  • Y10S430/134—Brightener containing

Definitions

• the present invention relates to a process for brightening the white surface of papers provided with one or more surface coatings composed of materials which are not able to bind securely optical brightening agents, and more particularly relates to a process for brightening the white areas in photographic images by means of such agents whilst bleeding of the brightening agents from the photographic layers is inhibited.
• water-soluble polymers suitable for use according to the present invention are mentioned polyvinyl pyrrolidone, polyvinyl-Z-oxazolidone and the copolymer of vinyl pyrrolidone and vinyl acetate having preferably a ratio of vinyl pyrrolidone to vinyl acetate units of at least 60:40.
• polyvinyl alcohol is used as the water-soluble polymer of this invention, the results obtained are substantially less satisfactory than with the polymers just mentioned.
• the fluorescent compound and the water-soluble polymer may be applied to or incorporated in paper itself, and/or baryta layer, a protective layer or some other auxiliary layer which may be present; in the case of a lightsensitive material, the said fluorescent and polymer components may be added to the silver halide emulsion layer itself, or to any auxiliary layer if desired.
• the said components may, of course, be added to a substance or substances before forming a layer therefrom, e.'g. they may be added to a constituent or constituents of one or more layers of a photographic material. We would emphasize that it is not essential for the fluorescent compounds and the polymer to be present in one and the same layer. They may be added to or incorporated in different waterpermeable layers.
• this polymer into the photographic material or to apply it thereon as a coating and to add the fluorescent compound to a processing bath such as a developing bath, a stop bath and/ or a fixing bath.
• a processing bath such as a developing bath, a stop bath and/ or a fixing bath.
• suitable amounts of vinyl polymer are between 0.1 g. and 4 g. per sq. m. of paper.
• the amount of fluorescent compound added may in general be between 2 mg. and 500 mg. per sq. m.
• the amount of gelatin in a conventional paper emulsion is approximately g. per sq. m.
• the bleeding out of the brightening agent should be prevented during the several processing steps such as the treatment in a developing, bleaching, fixing and rinsing bath.
• the brightening agent is incorporated in a non-hardened hydrophilic colloid layer of a photographic material, or a layer of a photo-graphic material containing a certain amount of hydrophilic colloid as binding agent such as e.g. a baryta-coated layer, bleeding out of the brightening agent from such a layer during wet processing can be practically prevented by using in conjunction with the colloid, one of the above described vinyl polymers having a molecular weight not lower than about 100,000.
• the molecular weight of the vinyl polymer'does not have to be so high.
• said vinyl polymers preferably have a molecular weight not lower than a molecular weight of about 5,000, which molecular Weight is not too low for the results aimed at.
• the hardening agent need not necessarily be added to the emulsion composition, when strong hardening is necessary a sudden gelling of the emulsion or too high an in crease of the viscosity of the coating composition is prevented preferably by treating the coated layer with a hardening solution (imbibition) or by a hardening realized by diffusion of hardening agent from an adjacent layer (e.g. a baryta layer) or even support such as a paper support to the emulsion layer.
• a hardening solution imbibition
• a hardening realized by diffusion of hardening agent from an adjacent layer e.g. a baryta layer
• support such as a paper support to the emulsion layer.
• the following hardening agents for gelatin are also suited: dihydroxymethyl urea, glyoxal, monomethyl dimethyl hydantoin and some melamine-formaldehyde resins.
• the amount of above-mentioned vinyl polymers incorporated into the hardened or unhardened gelatin-containing layers of a photographic material which has to be wet processed and wherein the bleeding out of the brightening agent is practically completely prevented may vary from 1 to 75% by weight relative to the amount of gelatin dependent on the kind of layer.
• gelatin-containing emulsion layers preferably do not contain more than 30% by weight of said vinyl polymers in respect of the amount of gelatin and on the other hand baryta-coated layers may contain up to 75 (preferably 10 to 75%) by weight of said vinyl polymers in respect of the amount of gelatin.
• the photographic materials are not to be wet processed such as e.g. photographic materials containing a print-out emulsion or electrophotographic materials used in xerography the problem of bleeding out of the brightening agent does not exist so that neither the molecular weight of the vinyl polymers nor the ratio of hydro-' philic colloid to the vinyl polymers nor the hardening degree of the colloid layers containing the said polymers and brightening agents are of great importance.
• the average molecular weight of the water-soluble polymer is sufficiently high (more than 100,000) for inhibiting the diffusion thereof from the layer or layers of the photographic material to which it is added, or if in combination with vinyl polymers with a molecular weight not lower than of about 5000 conventionally hardened gelatin layers are used, the strong affinity of the vinyl polymer for the respective fluorescent compounds will ensure that during the treatment and the rinsing steps these compounds are not washed out in such away that a loss of brightness arises, as it does it fluorescent compounds are used alone.
• the substantivity of the known fluorescent compounds for cellulose is so high that, if a photographic paper, the emulsion or the baryta layer of which contains such a fluorescent compound, is subjected to bath treatment simultaneously with paper containing no or less brightening agent, this fluorescent compound is adsorbed by the latter paper.
• a Water-soluble vinyl polymer as described above, is also present in the first mentioned photographic paper, no transfer of the fluorescent material occurs to the paper containing no or less brightening agent.
• a photographic material optically brightened according to the invention may contain color couplers, developing substances, surface-active compounds, sensitizers, antifogging agents, stabilizers, hardening agents, and plasticizers which can be worked up in known way in the photographic material.
• the method of optically brightening according to the present invention can be applied to all kinds of paper material and photographic material to be viewed by reflection such as for instance wall-paper, photographic positive paper for black-and-white and color photography for amateur and professional as well as graphic purposes, and positive paper used in the silver complex diffusion transfer process.
• the strips are rinsed for seconds, fixed for 10 minutes and finally rinsed for 3 hours in current water at 15 C.
• the surface whiteness of the strip B is more strongly brightened than that of strip A.
• Aqueous barium sulphate suspension 50% kg 2 Aqueous gelatin solution, 10% ccs 1000 4,4-bis(2 hydroxy 4 phenylamino 1,3,5 triazinyl-6) diaminostilbene 2,2 disodium sulphonate g 3.5
• the baryta-coated strip A is coated with a conventionally formalin hardened silver bromo-chloride emulsion, the coating composition of which contains 94 g. per kg. of gelatin.
• the baryta-coated strip B is coated with the same silver bromo-chloride emulsion, to which, however, per kg. of emulsion g. of polyvinyl pyrrolidone are added. After drying these two strips and exposure, they are developed and fixed as in Example 1.
• the surface 6 whiteness of strip B is more strongly brightened than that of strip A.
• EXAMPLE g3 A strip A of baryta-coated photographic paper is coated with a silver chloride paper emulsion formalin hardened in a known way, containing g. of gelatin and 1 g. of 4,4-bis(2-hydroxy-4-phenylamino-1,3,5-triazinyl 6) diaminostilbene-2,2-disodium sulphonate per kg. of emulsion.
• a strip B of baryta-coated photographic paper is coated with the same silver chloride emulsion to which, however, per kg. of emulsion ccs. of an aqueous solution containing 10 g. of polyvinyl-Z-oxazolidone are added. After drying these two strips and exposure they are developed and fixed as in Example 1.
• the surface whiteness of the strip B is higher than that of strip A.
• EXAMPLE 4 A strip A of photographic paper is coated with a baryta layer of the following composition:
• Aqueous barium sulphate suspension 50% kg 2 Aqueous gelatin solution, 10% ccs 1000 4,4 bis(2,4-dimethoxypropylamino-1,3,S-triazinyl- 6)-diaminostilbene-2,2'-disulphonic acid g 3.9
• a strip B of the same paper quality is coated with the same baryta composition to which, however, per kg. of baryta composition 33 g. of polyvinyl pyrrolidone were added.
• Both baryta-coated strips are coated with a silver bromo-iodide paper emulsion the coating composition of which contains per kg. 100 g. of gelatin and 1.6 g. of chrome alum. After drying these two strips and exposure they are developed and fixed as in Example 1.
• the sur face whiteness of the strip B is more strongly brightened than that of strip A.
• EXAMPLE 5 A strip A of photographic paper is coated with a baryta layer of the following composition:
• Aqueous barium sulphate suspension 50% kg 2 Aqueous gelatin solution, 10% ccs 1000 4,4 bis[2,4-di(4-phenyl)-anilino-l,3,5-triaZinyl-6]- diaminostilbene-Z,2-disulphonic acid g 4
• a strip B of the same paper quality is coated with the same baryta composition to which, however, per kg. of baryta composition 36.5 g. of polyvinyl pyrrolidone were added. Both baryta-coated strips are coated with a silver bromo-iodide paper emulsion. strips and exposure, they are developed and fixed as in Example 1.
• the surface whiteness of the strip B is more strongly brightened than that of strip A.
• EXAMPLE 6 As in Example 4, but instead of 3.5 g. of 4,4'-bis(2- hydroxy 4 phenylamino-1,3,5-triazinyl-6)-diamino-stilbenc-2,2-disodium sulphonate are used 3.75 g. of 4,4'-bis [2 amino 4-(beta hydroxyethylamino)-1,3,5-triazinyl- 6] -diaminostilbene-2,2-disodium sulphonate.
• EXAMPLE 7 A strip A of baryta-coated photographic paper is coated with a silver bromide paper emulsion which per kg. of emulsion contains 1 g. of 4,4-bis(4-phenylcarbamyl)-diiaminostilbene-2,2-disodium sulphonate and 75 g. of gelatin. The said emulsion is formalin hardened in a known way.
• a strip B of baryta-coated photographic paper is coated with the same silver bromide emulsion to which, however, per kg. of emulsion 100 ccs. of an aqueous solution containing 10 g. of polyvinyl pyrrolidone were added.
• Example 1 After drying these two strips and exposure, they are developed and fixed such as in Example 1.
• the whiteness of the surface color of the strip B thus treated is not lost on rinsing and strip B yields after complete finish a photographic image wherein the light parts are more strongly brightened as compared to the whiteness of strip A.
• a strip A of baryta-coated photographic paper is coated with a silver bromo-iodide paper emulsion formalin hardened in a known way which per kg. of emulsion contains 1 g. of 4,4-bis(2-hydroxy-4-phenylamino-l,3,5-triazinyl- 6)-diaminostilbene-2,Zdisodium sulphonate and 130 g. of gelatin.
• a strip B of baryta-coated photographic paper is coated with the same silver bromo-iodide emulsion to which, however, per kg. of emulsion 10 g.
• EXAMPLE 10 On a paper support A is coated a layer composed of a suspension of 280 g. of barium sulphate in 1500 ccs. of a 2% aqueous gelatin solution to which 0.6 g. of 4,4'-bis (2 hydroxy 4-phenylamino-1,3,5-triaZinyl-6)-diaminostilbene-2,2-disodium sulphonate in 30 cos. of water has been added. Thereupon an unhardened precipitating layer is coated consisting of an aqueous gelatin solution containing colloidal silver sulphide nuclei.
• This material is brought into contact with a negative silver halide emulsion layer which has previously been exposed to actinic light.
• the non-exposed silver halide diffuses from the negative material into the positive receiving layer and produces a positive image on the receptive layer on paper support A.
• a paper support B On a paper support B a layer is coated having the same composition as the baryta layer coated on paper support A to which, however, 6 g. of polyvinyl pyrrolidone in 30 ccs. of water have been added.
• the paper support B is coated with a precipitating layer comprising silver sulphide nuclei.
• EXAMPLE 11 On a strip A of a photographic paper, provided with a baryta layer, a silver bromide paper emulsion formalin hardened in a known Way and containing 75 g. of gelatin per kg. is coated. A strip B of a photographic material provided with a baryta layer is coated with the same silver bromide emulsion to which, however, 100 ccs. of an aqueous solution containing 20 g. of polyvinyl pyrrolidone per kg. of emulsion are added. After drying the two strips and exposure, they are developed and fixed as in Example 1 with the exception that 0.5 g.
• EXAMPLE 12 Two strips A and B of photographic paper are coated with a baryta layer of the following composition:
• Aqueous barium sulphate suspension 50% kg 2 Aqueous gelatin solution, 10% ccs 1000 4,4'-bis(2-hydroxy-4-phenylamino 1,3,5-triazinyl- 6)-diaminostilbene-2,2-disodium sulfonate g 3.5
• the baryta-coated strip A is coated with a silver bromide paper emulsion the coating composition of which contains per kg. 100 g. of gelatin and 0.8 g. of formaldehyde.
• the emulsion is coated so that 1 kg. covers 10 sq. m.
• the baryta-coated strip B is coated with the same silver bromide paper emulsion, to which, however, per kg. of emulsion 20 g. of polyvinyl pyrrolidone (average molecular weight: 50,000) are added. After drying these two strips are exposed to white light and developed at 20 C. for 1.5 min. in a developing bath of the following composition:
• the strips are treated for 5 sec. in a stop-bath of the following composition:
• a strip A of baryta-coated photographic paper is coated pro rata of 1 kg. per 8 sq. m. with a silver chloride paper emulsion containing per kg. of emulsion 1 g. of 4,4'-bis(2- hydroxy-4-phenylamino-1,3,5-triazinyl 6) diaminostilbene-2,2'-disodium sulfonate, 80 g. of gelatin and mg. of formaldehyde.
• a strip B of baryta-coated photographic paper is coated with the same silver chloride paper emulsion to which, however, per kg.
• the relative reflection values are measured as described in Example 12 and listed in the following table.
• a strip A of baryta-coated photographic paper is coated pro rata of 1 kg. per sq. m. with a silver bromide paper emulsion which contains per kg. of emulsion l g. of 4,4'- bis(4-phenylcarbamyl)-diaminostilbene-2,2-disodium sulfonate, 100 g. of gelatin and 120 mg. of formaldehyde.
• a strip B of baryta-coated photographic paper is coated With' the same silver bromide paper emulsion to which, however, per kg. of emulsion 100 ccs. of an aqueous solution containing 10 g. of polyvinyl pyrrolidone (average molecular weight: 18,000) were added. After drying and exposure to white light, these two strips are developed and fixed as described in Example 12.
• a photographic material comprising a support bearing a layer of a baryta coating containing gelatin as the essential binding agent and at least one gelatin silver halide emulsion layer containing gelatin as the essential binding agent, said material being characterized in that at least one of said layers has homogeneously distributed through the gelatin thereof an anionic water-soluble 4,4'- diaminostilbene fluorescent compound adapted for optically brightening said material, said fluorescent compound being incorporated in said gelatin in the dissolved state and one of said layers has homogeneously distributed throughout the gelatin thereof a Water-soluble vinyl polymer selected from the .group consisting of polyvinyl pyrrolidone, polyvinyl-Z-oxazolidone, and a vinyl pyrrolidone-vinyl acetate copolymer, said polymer being incorporated .in said gelatin in the dissolved state whereby the brightness of said material is enhanced.
• An improved method of brightening an image-receiving material bearing a precipitating layer containing gelatin as the essential binding agent which comprises incorporating into said layer a water-soluble vinyl polymer selected from the group consisting of polyvinyl pyrrolidone, polyvinyl-Z-oxazolidone, and a vinyl pyrrolidone-vinyl acetate copolymer and an anionic water-soluble 4,4-diarninostilbene fluorescent compound for brightening said material, both said vinyl polymer and said fluorescent compound being incorporated into said layer in the dissolved state.
• a water-soluble vinyl polymer selected from the group consisting of polyvinyl pyrrolidone, polyvinyl-Z-oxazolidone, and a vinyl pyrrolidone-vinyl acetate copolymer and an anionic water-soluble 4,4-diarninostilbene fluorescent compound for brightening said material, both said vinyl polymer and said fluorescent compound being incorporated into said layer in the dissolved state.
• An improved method of brightening a photographic non-light-sensitive image-receiving material bearing a layer containing gelatin as the essential binding agent which comprises incorporating into said layer a watersoluble vinyl polymer selected from the group consisting of polyvinyl pyrrolidone, polyvinyl-Z-oxazolidone, and a vinyl pyrrolidone-vinyl acetate copolymer and an anionic diaminostilbene fluorescent compound for brightening said material, both said vinyl in said fluorescent compound being incorporated in the dissolved state.
• a photographic material bearing a surface layer containing gelatin as the essential binding agent said layer having homogeneously distributed throughout the gelatin thereof an addition compound of a water-soluble vinyl resin selected from the group consisting of polyvinyl pyrrolidone, polyvinyl-Z-oxazolidone, and a vinyl pyrrolidone-vinyl acetate copolymer, and an anionic water-soluble 4,4'-diaminostilbene fluorescent compound for brightening said material obtained by contacting said vinyl resin and said fluorescent compound in the dissolved state.
• a water-soluble vinyl resin selected from the group consisting of polyvinyl pyrrolidone, polyvinyl-Z-oxazolidone, and a vinyl pyrrolidone-vinyl acetate copolymer
• an anionic water-soluble 4,4'-diaminostilbene fluorescent compound for brightening said material obtained by contacting said vinyl resin and said fluorescent compound in the dissolved state.
• a Water-soluble vinyl resin selected from the group consisting of a watersoluble vinyl resin selected from the group consisting of polyvinyl pyrrolidone, polyvinyl-Z-oxazolidone, and a vinyl pyrrolidone-vinyl acetate copoly
• a photographic material comprising a gelatin-containing layer wherein said gelatin is the essential binding agent of said layer, said layer having homogeneously distributed throughout the gelatin thereof an addition compound of a water-soluble vinyl resin selected from the group consisting of polyvinyl pyrrolidone, polyvinyl- 2-oxazolidone and a vinyl pyrrolidone-vinyl acetate copolymer, and an anionic Water-soluble 4,4'- diaminostilbene fluorescent compound for brightening said material 1 1 obtained by contacting said vinyl resin and said fluorescent compound in the dissolved state, said vinyl resin having a molecular Weight of at least 100,000, the ratio of vinyl resin to gelatin in the said layer ranging from 1 to 75% by weight.
• a water-soluble vinyl resin selected from the group consisting of polyvinyl pyrrolidone, polyvinyl- 2-oxazolidone and a vinyl pyrrolidone-vinyl acetate copolymer
• said fluorescent compound is selected from the group consisting of bis- N-acyl and bis-N-triazinyl derivatives of 4,4-diaminostilbene.
• said fluorescent compound is selected from the group consisting of his- N-acyl and bis-N-triazinyl derivatives of 4,4-diaminostilbene.
• said fluorescent compound is selected from the group consisting of bis- N-acyl and bis-N-triazinyl derivatives of 4,4-diaminostilbene.
• said fluorescent compound is selected from the group consisting of his- N-acyl and bis-N-triazinyl derivatives of 4,4'-diaminostilbene.
• said fluorescent compound is selected finom Ithe group consisting of his- N-acyl and 'bis-N-triazinyl derivatives of 4,4'-diaminostilbene.

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• Wood Science & Technology (AREA)
• Zoology (AREA)
• Food Science & Technology (AREA)
• Polymers & Plastics (AREA)
• Paper (AREA)
• Compositions Of Macromolecular Compounds (AREA)

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• 0
  • NL NL251799D patent/NL251799A/xx unknown
• 1959
  • 1959-05-19 GB GB18950/64A patent/GB967892A/en not_active Expired
  • 1959-05-19 GB GB16820/59A patent/GB967891A/en not_active Expired
• 1960
  • 1960-05-18 DE DE1960G0029703 patent/DE1245729C2/de not_active Expired
  • 1960-05-18 BE BE590935A patent/BE590935A/nl unknown
• 1964
  • 1964-03-27 US US355446A patent/US3269840A/en not_active Expired - Lifetime

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