EP0052735A1 - White photographic paper support and method of producing the same - Google Patents

White photographic paper support and method of producing the same Download PDF

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Publication number
EP0052735A1
EP0052735A1 EP81108099A EP81108099A EP0052735A1 EP 0052735 A1 EP0052735 A1 EP 0052735A1 EP 81108099 A EP81108099 A EP 81108099A EP 81108099 A EP81108099 A EP 81108099A EP 0052735 A1 EP0052735 A1 EP 0052735A1
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EP
European Patent Office
Prior art keywords
alkaline earth
support material
material according
photographic support
photographic
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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.)
Granted
Application number
EP81108099A
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German (de)
French (fr)
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EP0052735B1 (en
Inventor
Rudolf Dr.-Ing. Wanka
Heinz Dipl.-Ing. Wilke
Wolfram Wysk
Uwe Jensen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Felix Schoeller Jr Foto und Spezialpapiere GmbH
Felex Schoeller Jr and GmbH and Co KG
Original Assignee
Felix Schoeller Jr Foto und Spezialpapiere GmbH
Felex Schoeller Jr and GmbH and Co KG
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Application filed by Felix Schoeller Jr Foto und Spezialpapiere GmbH, Felex Schoeller Jr and GmbH and Co KG filed Critical Felix Schoeller Jr Foto und Spezialpapiere GmbH
Priority to AT81108099T priority Critical patent/ATE11835T1/en
Publication of EP0052735A1 publication Critical patent/EP0052735A1/en
Application granted granted Critical
Publication of EP0052735B1 publication Critical patent/EP0052735B1/en
Expired legal-status Critical Current

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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • 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
    • G03C1/79—Macromolecular coatings or impregnations therefor, e.g. varnishes
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/25—Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/25—Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
    • Y10T428/256—Heavy metal or aluminum or compound thereof
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/25—Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
    • Y10T428/258—Alkali metal or alkaline earth metal or compound thereof
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/31504—Composite [nonstructural laminate]
    • Y10T428/31855—Of addition polymer from unsaturated monomers
    • Y10T428/3188—Next to cellulosic
    • Y10T428/31895—Paper or wood
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/31504—Composite [nonstructural laminate]
    • Y10T428/31855—Of addition polymer from unsaturated monomers
    • Y10T428/3188—Next to cellulosic
    • Y10T428/31895—Paper or wood
    • Y10T428/31899—Addition polymer of hydrocarbon[s] only
    • Y10T428/31902—Monoethylenically unsaturated

Definitions

  • the invention relates to a photographic paper support, in particular a waterproof coated paper support for photographic purposes, the top coating of which contains a white pigment.
  • Waterproof photographic papers consist of a paper support with synthetic resin films applied on both sides and a photosensitive coating consisting of one or more layers based on silver salts on one of the synthetic resin surfaces.
  • the light-sensitive layers can be black and white as well as color photographic layers.
  • the synthetic resin films lying on the base paper can be made of polyolefin, e.g. As polyethylene, exist and are layered on the paper by means of extrusion coating. However, they can also be formed from organically dissolved paint mixtures, as described, for example, in DP 912 173.
  • the synthetic resin film (front coating) arranged under the light-sensitive layers usually contains light-reflecting white pigment and optionally shading dyes, optical brighteners and / or other additives such as lubricants and antistatic compounds.
  • the synthetic resin film (back coating) arranged on the paper side opposite the light-sensitive layers can be pigmented or pigment-free and / or contain other additives which result from the respective use of the laminate as a photographic support.
  • this layer can be coated with other functional layers (e.g. layers for the writeability, antistatic layers, sliding layers, opaque layers, etc.).
  • the most important component in the front coating between the base paper and light-sensitive layers is the light-reflecting white pigment in addition to the hydrophobic synthetic resin binder.
  • This white pigment is not only decisive for the visual impression of a photographic image, but also for the image quality and the durability of the photographic image produced in the adjacent photographic layers.
  • a number of publications and inventions therefore deal with the pigmentation of this hydrophobic front coating of the paper support.
  • the pigmentation of a polyolefin-based front coating to be applied by means of extrusion coating is the subject of several investigations.
  • DOS 2529 989 proposes the use of a special anatase titanium dioxide which has been surface-treated with aluminum oxide hydrate because the whiteness is higher than that of the common rutile titanium dioxide according to US Pat. No. 3,833,380. And in US Pat. No. 4,185,480 the combined use of rutile titanium dioxide is disclosed Anatase titanium dioxide is proposed because such a mixture advantageously combines the opacity, lightfastness and image sharpness inherent in the rutile with the higher whiteness inherent in the anatase and better compatibility with optical brighteners.
  • DOS 2 654 220 suggests e.g. the use of 5-40% calcium carbonate as white pigments, which leads to a reduction in production, due to its small particle diameter of less than 0.4 to improve the surface properties and to make a special surface treatment imparting the adhesion of photographic layers superfluous.
  • photographic paper supports which contain calcium carbonate in accordance with DOS 2 654 220 in the stated amounts are unsuitable because carbon dioxide is released during the usual treatment of photographs produced therewith in the photographic baths, some of which are acidic. The fine bubbles thus formed below the photographic layers lead to premature damage to the photographic layers. In addition, the sharpness of the photographic images produced with such papers has deteriorated significantly.
  • optical brighteners such as B. 2,5-di (5-tert.butyl-benzoxazolyl-2 ') thiophene for pigmented image carrier layer has long been known. Like the shade, the optical brightening is essentially determined by the respective properties of the photographic layers and the prevailing public taste.
  • the pigmented and optionally nuanced and / or lightened white front layer applied by means of extrusion coating is usually surface-treated after it has solidified in order to ensure that photographic layers arranged thereon adhere well despite the hydrophobic character of the synthetic resin. Such procedures for mediating liability have been described many times.
  • the corona treatment of the hydrophobic surface described in DOS 1447 611 is preferably used. But any other oxidizing surface treatment as well as special adhesion-promoting thin intermediate layers (e.g. according to DOS 1447 611) are suitable to ensure a safe coating with photographic coating mixtures and secure anchoring of the light-sensitive layers on the surface.
  • a disadvantage of the pigmented front layers composed according to the described prior art is first of all that all the white pigments described, with the exception of the calcium carbonate used in DOS 2654 220, promote the degradation of the polyolefinic synthetic resin binder.
  • degradation products cause severe corrosion on the die lips after just a few days to a maximum of 2 weeks. It is therefore necessary to regrind them at short intervals, otherwise the profile of the coating applied from the melt will become uneven and, in extreme cases, the surface will become contaminated.
  • a particularly serious disadvantage of the known prior art becomes apparent when small amounts of colored pigments or optical brighteners are processed together with the white pigment. Then it becomes apparent in the extruded film that, in particular when using a titanium dioxide as white pigment, previously inexplicable inhomogeneities occur in the pigment distribution, which are visible in the direction of travel as strips of different color intensity and thickness. It is conceivable that irreversible agglomerations have arisen as a result of a surface reaction of the pigment with the binder, but reactive tangles may also have arisen as a result of polymer degradation, for example starting from TiO 2 , which lead to so-called "yellow bodies". It is crucial that an undesirable longitudinal streak is visible in the coated material, which is based on an uneven pigment distribution, which up to now could not be avoided with certainty.
  • the object of the invention is therefore to create a waterproof white photographic paper support which has the opacity and whiteness of a material coated with titanium dioxide in polyolefin, but avoids the disadvantages of this mixing system.
  • an addition of 0.05 to 10% by weight of a carbonate and / or 0.05 to 20% by weight of an oxide of an alkaline earth metal is used.
  • the additional proportion of the oxides and / or carbonates of the alkaline earths can, if desired, also be above 20% by weight, e.g. B. at 25 or even 30 wt .-%.
  • B. e.g. 20 or even 30 wt .-%.
  • the incorporation of such amounts in addition to, for example, 15-20% rutile and / or anatase does not pose any problems.
  • the preferred application range is 0.1 to 5% by weight of a carbonate and / or 0.2 to 10% by weight of an oxide.
  • Oxides and carbonates of calcium or magnesium are preferred, but the corresponding compounds of strontium and barium are also suitable as additives according to the invention for polyolefin coating compositions containing titanium dioxide for the extrusion coating of photographic papers.
  • the paper base which is coated with a pigmented and stabilized polyolefin mixture according to the invention can be any photographic base paper which is either neutral-sized using alxylxetene dimer or has a known acidic size based on precipitated resin soaps, fatty acid soaps or fatty acid anhydrides.
  • the base papers preferably also carry a sealing and / or adhesion-imparting surface sizing made from water-soluble or water-dispersible substances. According to DAS 1422865 or DOS 2326759, the surface coating can contain antistatic substances as well as possibly pigments and / or hydrophobizing additives and / or coloring additives.
  • the base paper can be made exclusively from cellulose fibers or from mixtures of cellulose fibers with synthetic fibers. It can have a basis weight of 60-300 g / m 2 (preferably 70-200 g / m 2 ).
  • the pigment-containing polyolefin coating composition can be applied to one or both sides of the paper. It essentially consists of a polyolefin (80-95% by weight), a titanium dioxide (20-5% by weight) and an addition according to the invention of 0.05-20% by weight of an alkaline earth metal carbonate or oxide. It can optionally contain optical brighteners and / or shading dyes and / or antioxidants and / or lubricants and is applied by means of extrusion coating at customary temperatures of 280 to 300 ° C.
  • the polyolefin is preferably polyethylene. Both high density and low density polyethylene can be used.
  • the polyolefin resin can also be an ethylene copolymer or polypropylene.
  • a photographic base paper weighing approx. 130 g / m 2 was coated with approx. 30 g / m 2 of a pigmented synthetic resin mixture on the front by means of extrusion coating.
  • the composition of the mixture was The back was coated with about 30 g / m 2 of the same polyethylene mixture as in Examples 1-4.
  • a photographic base paper weighing approximately 130 g / m 2 was coated on both sides as in Example 6, with the difference that the front side coating contained 0.5% by weight of strontium carbonate instead of magnesium carbonate.
  • a photographic base paper weighing approximately 130 g / m 2 was coated on both sides as in Example 6, with the difference that the front coating contained 0.5% by weight calcium oxide instead of magnesium carbonate.
  • a photographic base paper weighing approx. 170 g / m 2 was coated on the front by means of extrusion coating with approx. 40 g / m 2 of a pigmented synthetic resin mixture.
  • the composition of the mixture was The back was coated with about 40 g / m 2 of the same polyethylene mixture as in Examples 1-4.
  • a photographic base paper weighing approximately 170 g / m 2 was coated on both sides as in Example 9, with the difference that the front coating contained 15% by weight of magnesium oxide instead of calcium oxide.
  • a photographic base paper weighing approximately 100 g / m 2 was coated on the front side with approximately 20 g / m 2 of a synthetic resin mixture by means of extrusion coating.
  • the composition of the mixture was The back was coated with about 20 g / m 2 of the same polyethylene mixture as in Examples 1-4.
  • a photographic base paper weighing approx. 70 g / m 2 was coated with approx. 15 g / m 2 of a synthetic resin mixture on the front by means of extrusion coating.
  • the composition of the mixture was:
  • the back was coated with about 15 g / m 2 of the same polyethylene mixture as in Examples 1 to 4.
  • Examples 13 to 24 As a comparison to the synthetic resin-coated photographic paper supports described in Examples 1 to 12, corresponding coated paper supports were produced as Examples 13 to 24, which differed from the examples according to the invention only in that the pigmented coating mixture on the front was free from that contained in Examples 1 to 12 Was alkaline earth oxide or alkaline earth carbonate.
  • Example 25 a coated paper according to example 1 of DOS 2 654 220 was produced. This example also serves as a comparative example.
  • coated carrier materials were compared both with regard to their different running behavior in the extrusion coating and with regard to the homogeneity of the coloring of the front layer, and after a conventional corona treatment of the surface they were coated with a light-sensitive silver halide layer and processed into photographic images. The photographic images were compared for sharpness.
  • Table 2 summarizes the main results of the tests. This clearly results in the superior quality of the coated photographic base papers produced according to the invention using mixtures of titanium dioxide with alkaline earth oxides or alkaline earth carbonates.
  • FIGS. 1 to 3 shows examples of white photographic paper supports with the invention in various configurations.
  • the reference number 1 designates the base paper
  • the reference number 2 the coating consisting of a polyolefin according to the invention, which is designed according to Examples 1 to 12.
  • Reference number 3 is, for example, an adhesion-promoting layer, possibly with additives such as a brightener
  • reference number 4 denotes the light-sensitive layer or layers
  • reference number 5 also the back coating made of a polyolefin, which can be transparent or pigmented, for example with carbon black.
  • the reference numeral 6 is a back line to make the photographic paper writable and / or to make it antistatic.
  • a primer 7 is provided between the polyolefin layer and the base paper, which is applied directly to the paper to give it additional smoothing or to serve as an adhesion promoter.
  • the reference numeral 8 is a backside coating, which serves here as an anti-curl layer, that is to prevent curling of the paper.

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  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • General Physics & Mathematics (AREA)
  • Paper (AREA)
  • Laminated Bodies (AREA)

Abstract

A photographic support material includes a base paper upon which a polyolefin coating is coated on at least one side. The coating includes titanium dioxide therein and at least one alkaline earth metal oxide in an amount of about 0.05-20% by weight of the coating, preferably calcium and/or magnesium oxide, and/or an alkaline earth metal carbonate in an amount of about 0.05-10% by weight of the coating, preferably calcium and/or magnesium carbonate.

Description

Die Erfindung betrifft einen fotografischen Papierträger, insbesondere einen wasserfest beschichteten Papierträger für fotografische Zwecke, dessen oberseitige Beschichtung ein weißes Pigment enthält.The invention relates to a photographic paper support, in particular a waterproof coated paper support for photographic purposes, the top coating of which contains a white pigment.

Wasserfeste fotografische Papiere bestehen aus einem Papierträger mit auf beiden Seiten aufgebrachten Kunstharzfilmen und einem aus einer oder mehrerem Schichten bestehenden auf Silbersalze basierenden lichtempfindlichen-Überzug auf einer der Kunstharzoberflächen. Bei den lichtempfindlichen Schichten kann es sich sowohl um schwarz/weiß- als auch um farbfotografische Schichten handeln.Waterproof photographic papers consist of a paper support with synthetic resin films applied on both sides and a photosensitive coating consisting of one or more layers based on silver salts on one of the synthetic resin surfaces. The light-sensitive layers can be black and white as well as color photographic layers.

Die auf dem Basispapier liegenden Kunstharzfilme können gemäß DAS 1447 815 aus Polyolefin, z. B. Polyäthylen, bestehen und mittels Extrusionsbeschichtung auf das Papier geschichtet werden. Sie können aber auch aus organisch gelösten Lackmischungen gebildet werden, wie es beispielsweise in DP 912 173 beschrieben ist.The synthetic resin films lying on the base paper can be made of polyolefin, e.g. As polyethylene, exist and are layered on the paper by means of extrusion coating. However, they can also be formed from organically dissolved paint mixtures, as described, for example, in DP 912 173.

Der unter der bzw. den lichtempfindlichen Schichten angeordnete Kunstharzfilm (Vorderseitenbeschichtung) enthält üblicherweise lichtreflektierendes Weißpigment sowie gegebenenfalls Nuancierfarbstoffe, optischen Aufheller und/oder andere Zusätze wie Gleitmittel und antistatisch wirkende Verbindungen.The synthetic resin film (front coating) arranged under the light-sensitive layers usually contains light-reflecting white pigment and optionally shading dyes, optical brighteners and / or other additives such as lubricants and antistatic compounds.

Der auf der den lichtempfindlichen Schichten entgegengesetzten Papierseite angeordnete Kunstharzfilm (Rückseitenbeschichtung) Kann pigmentiert oder pigmentfrei sein und/oder andere Zusätze enthalten, die sich aus der jeweiligen Verwendung des Laminates als fotografischer Träger ergeben. Außerdem kann diese Schicht mit weiteren funktionellen Schichten überzogen sein (z.B. Schichten für die Beschreibbarkeit, antistatische Schichten, Gleitschichten, lichtundurchlässige Schichten usw.).The synthetic resin film (back coating) arranged on the paper side opposite the light-sensitive layers can be pigmented or pigment-free and / or contain other additives which result from the respective use of the laminate as a photographic support. In addition, this layer can be coated with other functional layers (e.g. layers for the writeability, antistatic layers, sliding layers, opaque layers, etc.).

Wichtigster Bestandteil in der zwischen Basispapier und lichtempfindlichen Schichten liegenden Vorderseitenbeschichtung ist neben dem hydrophoben Kunstharzbinder das lichtreflektierende Weißpigment. Dieses Weißpigment ist nicht nur bestimmend für den visuellen Eindruck eines fotografischen Bildes, sondern auch für die Abbildungsqualität und die Haltbarxeit des in den angrenzenden fotografischen Schichten erzeugten fotografischen Bildes. Eine Reihe von Publikationen und Erfindungen befaßt sich daher mit der Pigmentierung dieser hydrophobierenden Vorderseitenbeschichtung des Papierträgers. Insbesondere ist die Pigmentierung einer auf Polyolefin basierenden und mittels Extrusionsbeschichtung aufzubringenden Vorderseitenbeschichtung Gegenstand mehrerer Untersuchungen.The most important component in the front coating between the base paper and light-sensitive layers is the light-reflecting white pigment in addition to the hydrophobic synthetic resin binder. This white pigment is not only decisive for the visual impression of a photographic image, but also for the image quality and the durability of the photographic image produced in the adjacent photographic layers. A number of publications and inventions therefore deal with the pigmentation of this hydrophobic front coating of the paper support. In particular, the pigmentation of a polyolefin-based front coating to be applied by means of extrusion coating is the subject of several investigations.

US 3833 380 beansprucht als Weißpigment in einer Polyäthylenschicht ein Rutil-Titandioxid, weil die an sich bekannte UV-Licht-Absorption des Rutils sich als vorteilhaft für die Haltbarxeit farb- fotografischer Bilder erwies.US 3833 380 claims as a white pigment in a polyethylene, a rutile titanium dioxide because the per se known UV light absorbers of the rutile proved to be advantageous for the color-photo Haltbarxeit g rafischer images.

DOS 2529 989 schlägt die Verwendung eines speziellen, mit Aluminiumoxidhydrat oberflächenbehandelten Anatas-Titandioxids vor, weil der Weißgrad höher ist als bei dem verbreiteten Rutil-Titandioxid gemäß US 3 833 380. Und in US 4 185 480 wird die kombinierte Verwendung von Rutil-Titandioxid mit Anatas-Titandioxid vorgeschlagen, weil eine solche Mischung in vorteilhafter Weise die dem Rutil eigene Deckkraft, Lichtbeständigkeit und Abbildungsschärfe mit der dem Anatas eigenen höheren Weiße und besseren Verträglichkeit mit optischem Aufheller kombiniert. DOS 2529 989 proposes the use of a special anatase titanium dioxide which has been surface-treated with aluminum oxide hydrate because the whiteness is higher than that of the common rutile titanium dioxide according to US Pat. No. 3,833,380. And in US Pat. No. 4,185,480 the combined use of rutile titanium dioxide is disclosed Anatase titanium dioxide is proposed because such a mixture advantageously combines the opacity, lightfastness and image sharpness inherent in the rutile with the higher whiteness inherent in the anatase and better compatibility with optical brighteners.

Die Verwendung weiterer Weißpigmente in Polyolefin-Beschichtungsmassen ist zwar in verschiedenen Publikationen beschrieben. Alle diese Vorschläge fanden jedoch wegen gravierender Nachteile keinen Eingang in die Praxis.The use of further white pigments in polyolefin coating compositions has been described in various publications. However, all of these suggestions were not put into practice due to serious disadvantages.

Gegen manche Pigmente entwickelte sich sogar ein Vorurteil, weil die beschriebenen Pigment-Uberzugsmischungen nicht zu einem funktionsfähigen Produkt nachgearbeitet werden können. DOS 2 654 220 schlägt z.B. die Verwendung von 5 - 40% Calciumcarbonat.als Weißpigmen vor,das zu einer Produktionsverbilligung führt, aufgrund seiner geringen Teilchendurchmesser von unter 0,4 um die Oberflächeneigenschaften verbessern und eine besondere die Haftung fotografischer Schichten vermittelnde Oberflächenbehandlung überflüssia.machen soll. Tatsächlich sind jedoch fotografische Papierträger, die gemäß DOS 2 654 220 Calciumcarbonat in den angegebenen Mengen enthalten, ungeeignet, weil während der üblichen Behandlung damit hergestellter Fotografien in den zum Teil sauren fotografischen Bädern Kohlendioxid freigesetzt wird. Die so unterhalb der fotografischen Schichten entstehenden feinen Bläschen führen zu einer vorzeitigen Beschädigung der fotografischen Schichten. Außerdem ist die Bildschärfe der mit solchen Papieren hergestellten fotografischen Bilder deutlich verschlechtert.There was even a prejudice against some pigments because the pigment coating mixtures described cannot be reworked into a functional product. DOS 2 654 220 suggests e.g. the use of 5-40% calcium carbonate as white pigments, which leads to a reduction in production, due to its small particle diameter of less than 0.4 to improve the surface properties and to make a special surface treatment imparting the adhesion of photographic layers superfluous. In fact, however, photographic paper supports which contain calcium carbonate in accordance with DOS 2 654 220 in the stated amounts are unsuitable because carbon dioxide is released during the usual treatment of photographs produced therewith in the photographic baths, some of which are acidic. The fine bubbles thus formed below the photographic layers lead to premature damage to the photographic layers. In addition, the sharpness of the photographic images produced with such papers has deteriorated significantly.

Es ist ferner bekannt, den pigmentierten Kunstharzüberzug durch Zusatz von Farbpigmenten zu nuancieren. Durch solche Zusätze kann nicht nur ein gelbliches Aussehen des Überzugs kompensiert werden, was z.B. bei Verwendung von T1O2-Rutil wünschenswert ist, sondern es wird auch der Weißeindruck der Oberfläche dem jeweiligen Geschmack angepaßt. Schließlich können Zusätze von kleinen Mengen farbiger Pigmente auch dazu dienen, spezifische Farbfehler von farbfotografischen Schichten zu kompensieren.It is also known to nuance the pigmented synthetic resin coating by adding color pigments. Such additives not only compensate for a yellowish appearance of the coating, which is desirable, for example, when using T1O 2 rutile, but also the white impression of the surface is appropriate Adapted to taste. Finally, additions of small amounts of colored pigments can also serve to compensate for specific color errors in color photographic layers.

Auch der Zusatz sogenannter optischer Aufheller z. B. 2,5-Di(5-tert.butyl-benzoxazolyl-2')thiophen zur pigmentierten Bildträgerschicht ist seit langem bekannt. Die optische Aufhellung wird wie die Farbnuancierung im wesentlichen durch die jeweiligen Eigenschaften der fotografischen Schichten und den vorherrschenden Publikumsgeschmack bestimmt.The addition of so-called optical brighteners such. B. 2,5-di (5-tert.butyl-benzoxazolyl-2 ') thiophene for pigmented image carrier layer has long been known. Like the shade, the optical brightening is essentially determined by the respective properties of the photographic layers and the prevailing public taste.

Die mittels Extrusionsbeschichtung aufgebrachte pigmentierte und gegebenenfalls nuancierte und/oder aufgehellte weiße Vorderseitenschicht wird nach ihrer Verfestigung üblicherweise oberflächenbehandelt, um zu erreichen, daß darauf angeordnete fotografische-Schichten trotz des hydrophoben Charakters des Kunstharzes gut haften. Solche der Haftungsvermittlung dienenden Verfahren sind vielfach beschrieben. Vorzugsweise wird die in DOS 1447 611 beschriebene Coronabehandlung der hydrophoben Oberfläche angewandt. Aber auch jede andere oxidierende Oberflächenbehandlung wie auch besondere haftvermittelnde dünne Zwischenschichten (z. B. gemäß DOS 1447 611) sind geeignet, um eine sichere Beschichtung mit fotografischen Überzugsmischungen und eine sichere Verankerung der lichtempfindlichen Schichten auf der Oberfläche zu gewährleisten.The pigmented and optionally nuanced and / or lightened white front layer applied by means of extrusion coating is usually surface-treated after it has solidified in order to ensure that photographic layers arranged thereon adhere well despite the hydrophobic character of the synthetic resin. Such procedures for mediating liability have been described many times. The corona treatment of the hydrophobic surface described in DOS 1447 611 is preferably used. But any other oxidizing surface treatment as well as special adhesion-promoting thin intermediate layers (e.g. according to DOS 1447 611) are suitable to ensure a safe coating with photographic coating mixtures and secure anchoring of the light-sensitive layers on the surface.

.Nachteilig an den gemäß dem beschriebenen Stand der Technik zusammengesetzten pigmentierten Vorderseitenschichten ist zunächst, daß alle beschriebenen Weißpigmente mit Ausnahme des in DOS 2654 220 benutzten Calciumcarbonates den Abbau des polyolefinischen Kunstharzbinders fördern. Während einer Extrusionsbeschichtung mittels Breitschlitzdüsen bewirken Abbauprodukte bereits nach wenigen Tagen bis maximal 2 Wochen starke Korrosionserscheinungen an den Düsenlippen. Deshalb ist es erforderlich, diese in kurzen Abständen nachzuschleifen, da andernfalls das Profil des aus der Schmelze aufgebrachten Überzuges ungleichmäßig wird und im Extremfall eine Verunreinigung der Oberfläche eintritt.A disadvantage of the pigmented front layers composed according to the described prior art is first of all that all the white pigments described, with the exception of the calcium carbonate used in DOS 2654 220, promote the degradation of the polyolefinic synthetic resin binder. During extrusion coating using slot dies, degradation products cause severe corrosion on the die lips after just a few days to a maximum of 2 weeks. It is therefore necessary to regrind them at short intervals, otherwise the profile of the coating applied from the melt will become uneven and, in extreme cases, the surface will become contaminated.

Eine andere Folge des ungünstigen Einflusses der verwendeten Weißpigmente ist, daß die Zerstörung des Binders, z.B. Polyäthylen, auch nach Verarbeitung zu fotografischen Bildern fortschreitet. Zwar ist zur Verhinderung dieser vor allem bei Lichteinwirkung auftretenden Zerstörung der Bildträgerschicht vorgeschlagen, der überzugsmischung oder dem Basispapier Stabilisatoren und/öder Antioxidantien beizumischen. Der Effekt solcher Zusätze ist jedoch immer noch unbefriedigend.Another consequence of the unfavorable influence of the white pigments used is that the destruction of the binder, e.g. Polyethylene, even after processing into photographic images. In order to prevent this destruction of the image carrier layer, which occurs especially when exposed to light, it is proposed to add stabilizers and / or antioxidants to the coating mixture or the base paper. However, the effect of such additives is still unsatisfactory.

Ein besonders gravierender Nachteil des bekannten Standes der Technik zeigt sich, wenn zusammen mit dem Weißpigment kleine Mengen farbiger Pigmente oder optischer Aufheller verarbeitet werden. Dann wird im extrudierten Film erkennbar, daß insbesondere bei Verwendung eines Titandioxids als Weißpigment bislang nicht erklärbare Inhomogenitäten in der Pigmentverteilung auftreten, die in Laufrichtung als Streifen unterschiedlicher Farbintensität und Dicke sichtbar.sind. Es ist denkbar, daß aufgrund einer Oberflächenreaktion des Pigments mit dem Binder irreversible Agglomerationen entstanden sind, es können aber auch durch den z.B. vom TiO2 ausgehenden Polymerabbau reaktive Knäuel entstanden sein, die zu sog. "Gelbkörpern" führen. Entscheidend ist, daß im beschichteten Material eine unerwünschte Längsstreifigkeit sichtbar ist, der eine ungleichmäßige Pigmentverteilung zugrundeliegt, die bislang nicht sicher vermieden werden kann.A particularly serious disadvantage of the known prior art becomes apparent when small amounts of colored pigments or optical brighteners are processed together with the white pigment. Then it becomes apparent in the extruded film that, in particular when using a titanium dioxide as white pigment, previously inexplicable inhomogeneities occur in the pigment distribution, which are visible in the direction of travel as strips of different color intensity and thickness. It is conceivable that irreversible agglomerations have arisen as a result of a surface reaction of the pigment with the binder, but reactive tangles may also have arisen as a result of polymer degradation, for example starting from TiO 2 , which lead to so-called "yellow bodies". It is crucial that an undesirable longitudinal streak is visible in the coated material, which is based on an uneven pigment distribution, which up to now could not be avoided with certainty.

Die hier beschriebenen Nachteile treten grundsätzlich bei allen in der Literatur beschriebenen Weißpigmenten auf (TiO2, Sb2O3, ZrO2, TiP2O7) mit Ausnahme von Calciumcarbonat. Calciumcarbonat ist jedoch einerseits wegen der Gefahr einer CO2-Entwicklung in sauren Bädern, andererseits wegen seines niedrigen Brechungsindex nicht als Pigment in fotografischen Trägern geeignet. Eine Folge des niedrigen Brechungsindex ist die im Vergleich zu Ti02 enthaltenden Trägern deutlich schlechtere Bildschärfe.The disadvantages described here basically occur with all white pigments described in the literature (TiO 2 , Sb 2 O 3 , ZrO 2 , TiP 2 O 7 ) with the exception of calcium carbonate. However, calcium carbonate is not suitable as a pigment in photographic supports on the one hand because of the risk of CO 2 development in acid baths and on the other hand because of its low refractive index. One consequence of the low refractive index is that the image sharpness is significantly poorer than that of carriers containing Ti0 2 .

Aufgabe der Erfindung ist es daher, einen wasserfesten weißen fotografischen Papierträger zu schaffen, der die Deckkraft und Weiße eines mit Titandioxid in Polyolefin beschichteten Materials hat, aber die Nachteile dieses Mischungssystems vermeidet. Insbesondere ist es Aufgabe der Erfindung, ein Verfahren zur Beschichtung vorzuschlagen, durch das Korrosion an den Düsenlippen der Breitschlitzdüse völlig vermieden und auch bei Verwendung beliebiger Zusätze von Nuancierfarbpigmenten eine streifenfreie homogene Beschichtung mit Titandioxid enthaltenden Polyolefinmischungen ermöglicht wird.The object of the invention is therefore to create a waterproof white photographic paper support which has the opacity and whiteness of a material coated with titanium dioxide in polyolefin, but avoids the disadvantages of this mixing system. In particular, it is an object of the invention to propose a method for coating by which corrosion on the nozzle lips of the slot die is completely avoided and a streak-free homogeneous coating with titanium dioxide-containing polyolefin mixtures is made possible even with the use of any additives of shade pigments.

Diese Aufgabe wird dadurch gelöst, daß zur Beschichtung der Basispapiere solche Mischungen aus Polyolefin, Titandioxid und gegebenenfalls anderen Zusätzen verwendet werden, die zusätzlich ein Oxid oder/und ein Carbonat eines Erdalkalimetalls enthalten.This object is achieved in that for coating the B asispapiere such mixtures of polyolefin, titanium dioxide and optionally other additives are used which additionally contain an oxide and / or a carbonate of an alkaline earth metal.

Mit Vorteil wird ein Zusatz von 0,05 bis 10 Gew.-% eines Carbonates oder/und 0,05 bis 20 Gew.-% eines Oxides eines Erdalkalimetalls verwendet.Advantageously, an addition of 0.05 to 10% by weight of a carbonate and / or 0.05 to 20% by weight of an oxide of an alkaline earth metal is used.

Der zusätzliche Anteil an den Oxiden und/oder Carbonaten der Erdalkalien kann, falls gewünscht, auch oberhalb von 20 Gew.-% liegen, z. B. bei 25 oder gar 30 Gew.-%. überraschenderweise bereitet die Einarbeitung solcher Mengen zusätzlich zu beispielsweise 15 - 20% Rutil und/oder Anatas keinerlei Probleme.The additional proportion of the oxides and / or carbonates of the alkaline earths can, if desired, also be above 20% by weight, e.g. B. at 25 or even 30 wt .-%. Surprisingly, the incorporation of such amounts in addition to, for example, 15-20% rutile and / or anatase does not pose any problems.

Der bevorzugte Anwendungsbereich ist 0,1 bis 5 Gew.-% eines Carbonates oder/und 0,2 bis 10 Gew.-% eines Oxides. Bevorzugt sind Oxide und Carbonate des Calciums oder Magnesiums, aber auch die entsprechenden Verbindungen von Strontium und Barium eignen sich als erfindungsgemäße Zusätze zu Titandioxid enthaltenden Polyolefinüberzugsmassen für die Extrusionsbeschichtung von fotografischen Papieren.The preferred application range is 0.1 to 5% by weight of a carbonate and / or 0.2 to 10% by weight of an oxide. Oxides and carbonates of calcium or magnesium are preferred, but the corresponding compounds of strontium and barium are also suitable as additives according to the invention for polyolefin coating compositions containing titanium dioxide for the extrusion coating of photographic papers.

Die mit einer erfindungsgemäßen pigmentierten und stabilisierten Polyolefin-Mischung zn beschichtende Papierunterlage Kann ein be- liebiges fotografisches Basispapier sein, das entweder unter Verwendung von Alxylxetendimer neutral geleimt ist oder eine beKannte saure Leimung auf der Basis von gefällten Harzseifen, Fettsaureseifen oder Fettsäureanhydriden hat. Vorzugsweise tragen die Basispapiere außerdem eine abdichtende und/oder Haftung vermittelnde Oberflächenleimung aus wasserlöslichen oder in Wasser dispergierbaren Substanzen. Der Oberflächenstrich Kann gemäß DAS 1422865 oder DOS 2326759 antistatisch wirKsame Substanzen sowie gegebenenfalls Pigmente und/oder hydrophobierende Zusätze und/oder färbende Zusätze enthalten. Das Basispapier Kann ausschließlich aus Zellstoffasern oder aus Mischungen von zellstoffasern mit synthetischen Fasern hergestellt sein. Es Kann ein Flächengewicht von 60 - 300 g/m2 (vorzugsweise 70 - 200 g/m2) haben..The paper base which is coated with a pigmented and stabilized polyolefin mixture according to the invention can be any photographic base paper which is either neutral-sized using alxylxetene dimer or has a known acidic size based on precipitated resin soaps, fatty acid soaps or fatty acid anhydrides. The base papers preferably also carry a sealing and / or adhesion-imparting surface sizing made from water-soluble or water-dispersible substances. According to DAS 1422865 or DOS 2326759, the surface coating can contain antistatic substances as well as possibly pigments and / or hydrophobizing additives and / or coloring additives. The base paper can be made exclusively from cellulose fibers or from mixtures of cellulose fibers with synthetic fibers. It can have a basis weight of 60-300 g / m 2 (preferably 70-200 g / m 2 ).

Die Pigment enthaltende Polyolefinbeschichtungsmasse Kann auf einer oder-beiden Papierseiten aufgezogen sein. Sie besteht im wesentlichen aus einem Polyolefin (80 - 95 Gew.-%), einem Titandioxid (20 - 5 Gew.-%) sowie einem erfindungsgemäßen Zusatz von 0,05 - 20 Gew.-% eines ErdalKalicarbonates oder -oxides. Sie Kann gegebenenfalls optischen Aufheller und/oder Nuancierfarbstoffe und/oder Antioxidantien und/oder Gleitmittel enthalten und wird mittels Extrusionsbeschichtung bei üblichen Temperaturen von 280 bis 300 °C aufgezogen.The pigment-containing polyolefin coating composition can be applied to one or both sides of the paper. It essentially consists of a polyolefin (80-95% by weight), a titanium dioxide (20-5% by weight) and an addition according to the invention of 0.05-20% by weight of an alkaline earth metal carbonate or oxide. It can optionally contain optical brighteners and / or shading dyes and / or antioxidants and / or lubricants and is applied by means of extrusion coating at customary temperatures of 280 to 300 ° C.

Das Polyolefin ist vorzugsweise Polyäthylen. Es Kann sowohl Polyäthylen mit hoher Dichte als auch solches mit niedriger Dichte verwendet werden. Das Polyolefinharz Kann aber auch ein Äthylencopolymer oder Polypropylen sein.The polyolefin is preferably polyethylene. Both high density and low density polyethylene can be used. The polyolefin resin can also be an ethylene copolymer or polypropylene.

Die Erfindung wird anhand der nachfolgenden Beispiele näher beschrieben.The invention is described in more detail with reference to the following examples.

Beispiele 1 - 4Examples 1-4

Ein ca. 160 g/m2 schweres unter Verwendung von AlKylKetendimer geleimtes fotografisches Basispapier mit einer Oberflachenleimung

Figure imgb0001
aus Stärke und Natriumsulfat (gemaß GB 1 346960) wurde mittels Extrusionsbeschichtung vorderseitig gemäß der Zusammenstellung in Tabelle 1 mit verschiedenen Mischungen auf Polyäthylenbasis überzogen. Das Überzugsgewicht betrug in allen Fällen ca. 38 g/m2, Die Gegenseite wurde bei allen Papieren mit ca. .38 g/m2 einer Mischung aus
Figure imgb0002
überzogen.An approximately 160 g / m 2 heavy sized using Al K ylKetendimer photographic B erflachenleimung asispapier with a Whether
Figure imgb0001
 starch and sodium sulfate (in accordance with GB 1 346960) was coated on the front by means of extrusion coating according to the composition in Table 1 with various mixtures based on polyethylene. The coating weight was in all cases about 38 g / m 2. The opposite side was made with a mixture of about .38 g / m 2 in all papers
Figure imgb0002
 overdrawn.

Beispiel 5Example 5

Ein ca. 130 g/m2 schweres fotografisches Basispapier wurde mittels Extrusionsbeschichtung vorderseitig mit ca. 30 g/m 2 einer pigmentierten Kunstharzmischung überzogen. Die Zusammensetzung der Mischung war

Figure imgb0003
Die RücKseite wurde mit ca. 30 g/m2 der gleichen Polyäthylenmischung wie bei den Beispielen 1-4 überzogen.A photographic base paper weighing approx. 130 g / m 2 was coated with approx. 30 g / m 2 of a pigmented synthetic resin mixture on the front by means of extrusion coating. The composition of the mixture was
Figure imgb0003
 The back was coated with about 30 g / m 2 of the same polyethylene mixture as in Examples 1-4.

Beispiel 6Example 6

Ein ca. 130 g/m2 schweres fotografisches Basispapier wurde vorderseitig mit ca. 30 g/m2 einer pigmentierten Kunstharzmischung überzogen. Die Zusammensetzung der Mischung war

Figure imgb0004
Die Rücxpeite wurde wie im Beispiel 5 überzogen.An approximately 130 g / m 2 heavy photographic B was asispapier front side coated with approx 30 g / m 2 of a pigmented resin mixture. The composition of the mixture was
Figure imgb0004
 The reverse side was covered as in Example 5.

Beispiel 7Example 7

Ein ca. 130 g/m2 schweres fotografisches Basispapier wurde wie im Beispiel 6 beidseitig überzogen mit dem Unterschied, daß der Vorderseitenüberzug 0,5 Gew.-% Strontiumcarbonat anstelle von Magnesiumcarbonat enthielt.A photographic base paper weighing approximately 130 g / m 2 was coated on both sides as in Example 6, with the difference that the front side coating contained 0.5% by weight of strontium carbonate instead of magnesium carbonate.

Beispiel 8Example 8

Ein ca. 130 g/m2 schweres fotografisches Basispapier wurde wie im Beispiel 6 beidseitig überzogen mit dem Unterschied, daß der Vorderseitenüberzug 0,5 Gew.-% Calciumoxid anstelle von Magnesiumcarbonat enthielt.A photographic base paper weighing approximately 130 g / m 2 was coated on both sides as in Example 6, with the difference that the front coating contained 0.5% by weight calcium oxide instead of magnesium carbonate.

Beispiel 9Example 9

Ein ca. 170 g/m schweres fotografisches Basispapier wurde mittels Extrusionsbeschichtung vorderseitig mit ca. 40 g/m2 einer pigmentierten Kunstharzmischung überzogen. Die Zusammensetzung der Mischung war

Figure imgb0005
Die Rückseite wurde mit ca. 40 g/m2 einer gleichen Polyäthylenmischung wie in den Beispielen 1 - 4 überzogen.A photographic base paper weighing approx. 170 g / m 2 was coated on the front by means of extrusion coating with approx. 40 g / m 2 of a pigmented synthetic resin mixture. The composition of the mixture was
Figure imgb0005
 The back was coated with about 40 g / m 2 of the same polyethylene mixture as in Examples 1-4.

Beispiel 10Example 10

Ein ca. 170 g/m2 schweres fotografisches Basispapier wurde wie im Beispiel 9 beidseitig überzogen mit dem Unterschied, daß der Vorderseitenüberzug 15 Gew.-% Magnesiumoxid anstelle von Calciumoxid enthielt.A photographic base paper weighing approximately 170 g / m 2 was coated on both sides as in Example 9, with the difference that the front coating contained 15% by weight of magnesium oxide instead of calcium oxide.

Beispiel 11Example 11

Ein ca. 100 g/m2 schweres fotografisches Basispapier wurde mittels Extrusionsbeschichtung vorderseitig mit ca. 20 g/m2 einer Kunstharzmischung überzogen. Die Zusammensetzung der Mischung war

Figure imgb0006
Die RücKseite wurde mit ca. 20 g/m2 einer gleichen Poly- äthylenmischung wie in den Beispielen 1 - 4 überzogen.A photographic base paper weighing approximately 100 g / m 2 was coated on the front side with approximately 20 g / m 2 of a synthetic resin mixture by means of extrusion coating. The composition of the mixture was
Figure imgb0006
 The back was coated with about 20 g / m 2 of the same polyethylene mixture as in Examples 1-4.

Beispiel 12Example 12

Ein ca.70 g/m2 schweres fotografisches Basispapier wurde mittels Extrusionsbeschichtung vorderseitig mit ca.15 g/m2 einer Kunstharzmischung überzogen. Die Zusammensetzung der Mischung war:

Figure imgb0007
Die Rückseite wurde mit ca.15 g/m2 einer gleichen Polyäthylenmischung wie in den Beispielen 1 bis 4 überzogen.A photographic base paper weighing approx. 70 g / m 2 was coated with approx. 15 g / m 2 of a synthetic resin mixture on the front by means of extrusion coating. The composition of the mixture was:
Figure imgb0007
 The back was coated with about 15 g / m 2 of the same polyethylene mixture as in Examples 1 to 4.

Vergleichsbeispiele:Comparative examples:

Als Vergleiche zu den in den Beispielen 1 bis 12 beschriebenen kunstharzbeschichteten fotografischen Papierträgern wurden als Beispiel 13 bis 24 entsprechende beschichtete Papierträger hergestellt, die sich von den erfindungsgemäßen Beispielen nur dadurch unterschieden, daß die vorderseitige pigmentierte Uberzugsmischung frei von dem in den Beispielen 1 bis 12 enthaltenen Erdalkalioxid oder Erdalkalicarbonat war.As a comparison to the synthetic resin-coated photographic paper supports described in Examples 1 to 12, corresponding coated paper supports were produced as Examples 13 to 24, which differed from the examples according to the invention only in that the pigmented coating mixture on the front was free from that contained in Examples 1 to 12 Was alkaline earth oxide or alkaline earth carbonate.

Als Beispiel 25 wurde schließlich ein beschichtetes Papier gemäß Beispiel 1 der DOS 2 654 220 hergestellt. Auch dieses Beispiel dient als Vergleichsbeispiel.Finally, as example 25, a coated paper according to example 1 of DOS 2 654 220 was produced. This example also serves as a comparative example.

Prüfung der beschichteten Trägermaterialien (Beispiele 1 - 25)Examination of the coated carrier materials (Examples 1-25)

Die beschichteten Trägermaterialien wurden sowohl hinsichtlich ihres unterschiedlichen Laufverhaltens bei der Extrusionsbeschichtung und hinsichtlich der Homogenität der Einfärbung der Vorderseitenschicht miteinander verglichen als auch nach üblicher Coronabehandlung der Oberfläche mit einer lichtempfindlichen Silberhalogenidschicht überzogen und zu fotografischen Bildern verarbeitet. Die fotografischen Bilder wurden bezüglich Bildschärfe miteinander verglichen.The coated carrier materials were compared both with regard to their different running behavior in the extrusion coating and with regard to the homogeneity of the coloring of the front layer, and after a conventional corona treatment of the surface they were coated with a light-sensitive silver halide layer and processed into photographic images. The photographic images were compared for sharpness.

In Tabelle 2 sind die wesentlichen Ergebnisse der Prüfungen zusammengestellt. Daraus ergibt sich eindeutig die überlegene Qualität der erfindungsgemäß unter Verwendung von Mischungen aus Titandioxid mit Erdalkalioxiden oder Erdalkalicarbonaten hergestellten beschichteten fotografischen Trägerpapiere.

Figure imgb0008
Table 2 summarizes the main results of the tests. This clearly results in the superior quality of the coated photographic base papers produced according to the invention using mixtures of titanium dioxide with alkaline earth oxides or alkaline earth carbonates.
Figure imgb0008

Zur weiteren Erläuterung sind in der beigefügten Zeichnung mit Fig. 1 bis 3 Beispiele weißer fotografischer Papierträger mit der Erfindung in verschiedener Ausgestaltung dargestellt. Das Bezugszeichen 1 bezeichnet das Basispapier, das Bezugszeichen 2 die aus einem Polyolefin gemäß der Erfindung bestehende Beschichtung, die gemäß Beispielen 1 bis 12 ausgestaltet ist. Das Bezugszeichen 3 ist beispielsweise eine haftvermittelnde Schicht, ggf. mit Zusätzen wie einem Aufheller, das Bezugszeichen 4 bezeichnet die lichtempfindliche Schicht oder Schichten, das Bezugszeichen 5 die Rückseitenbeschichtung ebenfalls aus einem Polyolefin, das transparent oder pigmentiert sein kann, beispielsweise mit Ruß. Das Bezugszeichen 6 ist ein Rückseitenstrich, um das fotografische Papier Beschreibbar zu machen und/oder antistatisch auszurüsten. In Fig. 3 ist zwischen der Polyolefinschicht und dem Basispapier noch ein Vorstrich 7 vorgesehen, der direkt auf das Papier aufgebracht ist, um diesem zusätzliche Glättung zu geben bzw. um als Haftvermittler zu dienen. Das Bezugszeichen 8 ist eine Rückseitenbeschichtung, die hier als Anticurlschicht dient, also ein Krümmen des Papiers verhindern soll.For further explanation, the accompanying drawing with FIGS. 1 to 3 shows examples of white photographic paper supports with the invention in various configurations. The reference number 1 designates the base paper, the reference number 2 the coating consisting of a polyolefin according to the invention, which is designed according to Examples 1 to 12. Reference number 3 is, for example, an adhesion-promoting layer, possibly with additives such as a brightener, reference number 4 denotes the light-sensitive layer or layers, reference number 5 also the back coating made of a polyolefin, which can be transparent or pigmented, for example with carbon black. The reference numeral 6 is a back line to make the photographic paper writable and / or to make it antistatic. In Fig. 3, a primer 7 is provided between the polyolefin layer and the base paper, which is applied directly to the paper to give it additional smoothing or to serve as an adhesion promoter. The reference numeral 8 is a backside coating, which serves here as an anti-curl layer, that is to prevent curling of the paper.

Claims (13)

1. Fotografisches Trägermaterial bestehend aus Papier und mindestens einer auf dem Papier angeordneten, Titandioxid sowie. gegebenenfalls Farbpigment und/oder gegebenenfalls optischen Aufheller enthaltenden Polyolefinschicht, dadurch gekennzeichnet, daß die Polyolefinschicht zusätzlich mindestens ein Oxid und/oder Carbonat eines Erdalkalimetalls enthält.1. Photographic support material consisting of paper and at least one arranged on the paper, titanium dioxide and. optionally polyolefin layer containing color pigment and / or optionally optical brightener, characterized in that the polyolefin layer additionally contains at least one oxide and / or carbonate of an alkaline earth metal. 2. Fotografisches Trägermaterial gemäß Anspruch 1, dadurch gekennzeichnet, daß die Polyolefinschicht 0,05 bis 10 Gew.-% eines Erdalkalicarbonates enthält.2. Photographic support material according to claim 1, characterized in that the polyolefin layer contains 0.05 to 10 wt .-% of an alkaline earth carbonate. 3. Fotografisches Trägermaterial gemäß Anspruch 1, dadurch gekennzeichnet, daß die Polyolefinschicht 0,05 bis 20 Gew.-% eines Erdalkalioxids enthält.3. Photographic support material according to claim 1, characterized in that the polyolefin layer contains 0.05 to 20 wt .-% of an alkaline earth metal oxide. 4. Fotografisches Trägermaterial gemäß Anspruch 1 und 2, dadurch gekennzeichnet, daß das Erdalkalicarbonat Calciumcarbonat ist.4. Photographic support material according to claim 1 and 2, characterized in that the alkaline earth carbonate is calcium carbonate. 5. Fotografisches Trägermaterial gemäß Anspruch 1 und 2, dadurch gekennzeichnet, daß das Erdalkalicarbonat Magnesiumcarbonat ist.5. Photographic support material according to claim 1 and 2, characterized in that the alkaline earth carbonate is magnesium carbonate. 6. Fotografisches Trägermaterial gemäß Anspruch 1 und 2, dadurch gekennzeichnet, daß das.Erdalkalicarbonat eine Mischung aus zwei oder mehr Erdalkalicarbonaten ist.6. Photographic support material according to claim 1 and 2, characterized in that the alkaline earth carbonate is a mixture of two or more alkaline earth carbonates. 7. Fotografisches Trägermaterial gemäß Anspruch 1 und 3, dadurch gekennzeichnet, daß das Erdalkalioxid Calciumoxid ist.7. Photographic support material according to claim 1 and 3, characterized in that the alkaline earth oxide is calcium oxide. 8. Fotografisches Trägermaterial gemäß Anspruch 1 und 3, dadurch gekennzeichnet, daß das Erdalkalioxid Magnesiumoxid ist.8. Photographic support material according to claim 1 and 3, characterized in that the alkaline earth oxide is magnesium oxide. 9. Fotografisches Trägermaterial gemäß Anspruch 1 und 3, dadurch gekennzeichnet, daß das Erdalkalioxid eine Mischung aus zwei oder mehr Erdalkalioxiden ist.9. Photographic support material according to claim 1 and 3, characterized in that the alkaline earth oxide is a mixture of two or more alkaline earth oxides. 10. Fotografisches Trägermaterial gemäß Anspruch 1, dadurch gekennzeichnet, daß die Polyolefinschicht eine Mischung aus Erdalkalicarbonat und Erdalkalioxid enthält.10. Photographic support material according to claim 1, characterized in that the polyolefin layer contains a mixture of alkaline earth carbonate and alkaline earth oxide. 11. Fotografisches Trägermaterial gemäß Anspruch 1 - 10, dadurch gekennzeichnet, daß die Gegenseite ebenfalls mit Polyolefin beschichtet ist.11. Photographic support material according to claims 1-10, characterized in that the opposite side is also coated with polyolefin. 12. Fotografisches Trägermaterial gemäß Anspruch 1 - 11, dadurch gekennzeichnet, daß die vorderseitige pigmentierte Schicht durch physikalische oder chemische Vorbehandlung für die Aufnahme einer fotografischen Schicht vorbereitet ist.12. Photographic support material according to claims 1-11, characterized in that the front pigmented layer is prepared by physical or chemical pretreatment for the inclusion of a photographic layer. 13. Verfahren zur Herstellung eines fotografischen Trägermaterials gemäß Anspruch 1 - 12 mittels Extrusionsbeschichtung mit Breitschlitzdüse, dadurch gekennzeichnet, daß in die Extrusionsschmelze Oxid und/oder Carbonat eines Erdalkalimetalls eingearbeitet wird.13. A method for producing a photographic support material according to claims 1-12 by means of extrusion coating with a slot die, characterized in that oxide and / or carbonate of an alkaline earth metal is incorporated into the extrusion melt.
EP81108099A 1980-11-21 1981-10-09 White photographic paper support and method of producing the same Expired EP0052735B1 (en)

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AT81108099T ATE11835T1 (en) 1980-11-21 1981-10-09 WHITE PHOTOGRAPHIC PAPER SUPPORT AND PROCESS FOR ITS MANUFACTURE.

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Application Number Priority Date Filing Date Title
DE3043864 1980-11-21
DE19803043864 DE3043864A1 (en) 1980-11-21 1980-11-21 WHITE PHOTOGRAPHIC PAPER CARRIER AND METHOD FOR THE PRODUCTION THEREOF

Publications (2)

Publication Number Publication Date
EP0052735A1 true EP0052735A1 (en) 1982-06-02
EP0052735B1 EP0052735B1 (en) 1985-02-13

Family

ID=6117244

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81108099A Expired EP0052735B1 (en) 1980-11-21 1981-10-09 White photographic paper support and method of producing the same

Country Status (5)

Country Link
US (1) US4396671A (en)
EP (1) EP0052735B1 (en)
JP (1) JPS57116339A (en)
AT (1) ATE11835T1 (en)
DE (1) DE3043864A1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0176656A2 (en) * 1984-09-28 1986-04-09 Felix Schoeller jr Foto- und Spezialpapiere GmbH & Co. KG Support material for black and white and colour photography
GB2217866A (en) * 1988-04-15 1989-11-01 Oji Paper Co Thermal transfer image-receiving sheet
EP0560992A1 (en) * 1991-10-03 1993-09-22 New Oji Paper Co., Ltd. Support for photographic printing paper and method of making said support
GB2279961A (en) * 1993-06-22 1995-01-18 Ici Plc Paint containing white opacifier
GB2280191A (en) * 1993-06-22 1995-01-25 Ici Plc Paint containing white opacifier

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DE3328463A1 (en) * 1983-08-06 1985-02-21 Felix Schoeller jr. GmbH & Co KG, 4500 Osnabrück PHOTOGRAPHIC PAPER CARRIER
US4710186A (en) * 1984-07-20 1987-12-01 Personal Products Company Clean and dry appearance facing
US4859539A (en) * 1987-03-23 1989-08-22 Eastman Kodak Company Optically brightened polyolefin coated paper support
US4794071A (en) * 1987-03-23 1988-12-27 Eastman Kodak Company Optically brightened photographic silver halide element with a polyolefin paper coated support
US5178936A (en) * 1989-05-23 1993-01-12 Oji Paper Co., Ltd. Support sheet for photographic printing sheet
US5058531A (en) * 1989-06-03 1991-10-22 Akins Edward A Feeder for animals
EP0492887B1 (en) * 1990-12-21 1997-08-27 Oji Paper Co., Ltd. Support sheet for photographic printing sheet
US5374508A (en) * 1990-12-21 1994-12-20 New Oji Paper Co., Ltd. Support sheet for photographic printing sheet
JPH05269941A (en) * 1992-01-27 1993-10-19 Mitsubishi Paper Mills Ltd Resin coated paper
US5262286A (en) * 1992-07-31 1993-11-16 Eastman Kodak Company Reduction of yellow stain in photographic prints
WO2012105944A1 (en) 2011-01-31 2012-08-09 Hewlett-Packard Development Company, L.P. Electrophotographic recording media

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US4010307A (en) * 1973-11-15 1977-03-01 Rhone-Progil Coating of paper, cardboard and the like and composition
JPS516531A (en) 1974-07-04 1976-01-20 Fuji Photo Film Co Ltd INGASHOSHI JITAI
JPS53117A (en) * 1976-06-24 1978-01-05 Mitsubishi Paper Mills Ltd Photographic paper support
JPS555830A (en) * 1978-06-28 1980-01-17 Fuji Photo Film Co Ltd Ink jet type recording sheet
US4265960A (en) * 1978-12-26 1981-05-05 Mobil Oil Corporation Films produced from LDPE encapsulated CaCO3
JPS5942296B2 (en) * 1980-08-01 1984-10-13 三菱製紙株式会社 Manufacturing method for photographic supports

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DE2734090A1 (en) * 1976-08-04 1978-02-09 Fuji Photo Film Co Ltd PHOTOGRAPHIC CARRIER
DE2654220A1 (en) * 1976-11-30 1978-06-01 Solvay Werke Gmbh Coating photographic paper with filled polyolefin - using low pressure polyethylene contg. fine calcium carbonate by extrusion and calendering

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0176656A2 (en) * 1984-09-28 1986-04-09 Felix Schoeller jr Foto- und Spezialpapiere GmbH & Co. KG Support material for black and white and colour photography
EP0176656A3 (en) * 1984-09-28 1988-09-21 Felix Schoeller Jr. Gmbh & Co Kg Support material for black and white and colour photography
GB2217866A (en) * 1988-04-15 1989-11-01 Oji Paper Co Thermal transfer image-receiving sheet
GB2217866B (en) * 1988-04-15 1992-02-12 Oji Paper Co Thermal transfer image-receiving sheet
EP0560992A1 (en) * 1991-10-03 1993-09-22 New Oji Paper Co., Ltd. Support for photographic printing paper and method of making said support
EP0560992A4 (en) * 1991-10-03 1994-04-06 Oji Paper Company Limited
US5470652A (en) * 1991-10-03 1995-11-28 Oji Paper Co., Ltd Support sheet for photographic printing paper and process for producing the sheet
GB2279961A (en) * 1993-06-22 1995-01-18 Ici Plc Paint containing white opacifier
GB2280191A (en) * 1993-06-22 1995-01-25 Ici Plc Paint containing white opacifier

Also Published As

Publication number Publication date
DE3043864C2 (en) 1987-09-10
US4396671A (en) 1983-08-02
DE3043864A1 (en) 1982-07-08
EP0052735B1 (en) 1985-02-13
JPS57116339A (en) 1982-07-20
ATE11835T1 (en) 1985-02-15

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