DE2145237A1 - Photographic carrier - Google Patents

Description

PA1ENTANWÄITE

DR. E. WIEGAND DIPL-ING. W. NIEMANN 2145237

DR. M. KÖHLER DIPL.-ING. C. GERNHARDT

MÖNCHEN HAMBURG TELEPHONE: 55547ί 8000 MONK EN 15, TELEGRAMS: KARPATENT NUSSBAUMSTRASSE 10

September 9, 1971 ¥. 40685/71 Ko / D

Fuji Photo PiIm Co., Ltd. Ashigara-Kamigun, Kanagawa (Japan)

Photographic carrier

5 The photographic support according to the invention is made of a base paper composed of a light-shielding black paper layer containing, for example, carbon black, and a white paper layer on at least one surface of the black paper layer that are used together in the web or 'arching process and a water-resistant synthetic resin layer on both of them Surfaces of the base paper built up, the synthetic resin for example made of polyethylene or cellulose triacetate consists. The obtained carrier has light-shielding properties, water resistance, dimensional stability, high resolution, graphic properties, printability and good looks.

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The invention "deals with photographic supports and particularly photographic supports having high light-shielding properties and water resistance properties.

The ordinary photographic papers included no light shielding layer and if they are from the back are exposed, fog is created. Therefore, photographic papers of this type must be placed under safety lights be treated. An attempt to make photographic papers that pass under white light Forming a light-shielding support processable to manufacture is set out in the British patent 1 183 613. It is also known from "Land camera photographic paper" by the Polaroid Land Company, that light-shielding properties are imparted to a support when a coating layer containing carbon black is applied to the back surface of the support or a light-shielding paper is attached thereto. In any case, the black light-shielding layer becomes belichtei ^ and those with ordinary lettering or with Pressure formed letters are difficult to read. Furthermore, water resistance is difficult to achieve and that external appearance appears unfavorable.

With a view to overcoming these defects, attempts have been made to form an additional water-resistant layer or a white coating layer. To do this, 3 ^{e <} 3 ° ^c h. an additional step is required and the resulting carrier becomes expensive and cumbersome to manufacture.

Extensive studies have been made to solve these problems within the scope of the invention. Because of the invention This results in a photographic carrier, which is a base paper, which consists of a light-shielding black Paper layer and a white paper layer on at least a surface of the same, which together in papermaking

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recruitment proceedings were formed, exists, and one water-resistant synthetic resin layer on both surfaces of the raw paper contains.

The raw paper used in the context of the invention shows a paper structure made up of a black paper layer and a white paper layer. the black paper layer contains carbon black or a dye to increase its light absorption properties. The color density or the thickness of the black paper layer will be according to the degree of light shielding required chosen. The coloring can be achieved by incorporating carbon black or a dye during the manufacture of the paper pulp can be achieved. The amount of the carbon black or the dye is about 1 to 20 wt .- ^, based on the Paper pulp, but this amount is not critical in the context of the invention. On the other hand, it is necessary that a white paper layer is present on at least one surface of the black paper layer, and if desired it can be present on both surfaces. To increase the reflectance of the light, a white pigment, such as titanium dioxide, clay, barium sulfate, lithopone or zinc sulfide can be incorporated into the white paper layer. the The thickness of the white paper layer is determined according to the desired covering properties. The base paper with the The above construction can be effected on a cylinder paper machine or a so-called combination paper machine multi-layer papermaking.

The resin layers are made according to suitable procedures the type of resin used, but they are usually from a melt or a solution upset. A typical example of the former method "is melt extrusion coating with polyethylene and

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a typical example of the latter method consists in coating a solution of cellulose triacetate in one Mixed solvent of acetone and methylene chloride. the The thickness of the resin layer varies according to the purpose of use and the resin to be peeled, but it is usually not less than 0.005 mm. Thinner coatings do not lead to sufficient water resistance or Water repellency.

The resin layer used in the context of the invention serves to make the carrier water-resistant or water-repellent the developing solution does not penetrate into the carrier and it also gives dimensional stability thereof.

The resins useful in the invention are high molecular weight compounds having film-forming properties, Adhesiveness to paper and water resistance and these include, for example, polyolefins, cellulose acetates, Polyethylene terephthalate, polyvinyl chloride, polyvinyl acetate or styrene-butadiene copolymers. Preferred White pigments that increase the surface reflectance, reducing the loss of sensitivity at the time the exposure and to increase the resolving power are those with excellent opacity, for example Titanium dioxide, zinc oxide, zinc sulfide or lithopone ■. If desired, the resin layer can also contain other additives, such as plasticizers, dyes or fluorescent bleaching agents.

Sometimes the surface of the resin layer that comes into contact with the photographic emulsion becomes a surface activation treatment such as ultraviolet ray irradiation, corona discharge or flame treatment and / or covered with an undercoat to protect your Increase adhesion to the emulsion. The opposite surface of the resin layer is preferably subjected to a surface rubbing treatment subject, so that their description

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properties and printability is increased or sliding or slipping is prevented.

The photographic supports according to the invention have high light-shielding properties, water resistance and water repellency, dimensional stability, high resolving power, labeling properties on the back Surface, printability and good appearance as photographic supports.

The following examples serve to further illustrate the invention.

example 1

2 parts by weight of unbleached kraft pulp from conifers trees and 2 parts of bleached kraft pulp of broad-leaved trees were dispegiert parts by weight of water in a hollander to 96 and geholländert degree of 5O ⁰ SR by means of a crusher of the Dutch-Type . Subsequently, 0.4 part by weight of carbon black, 0.1 part by weight of rosin size and 0.12 part by weight of aluminum sulfate were successively added to prepare a paper pulp (A) for use as a black paper layer. A separately prepared pulp slurry of the same composition which had been geholländert to a degree of 5O ⁰ SR was used and 0.3 parts by weight of titanium white, 0.1 parts by weight of rosin and. 0.12 parts by weight of aluminum sulfate were successively added to produce a paper pulp (B) for use as a white paper layer.

The paper pulp (A) was diluted 10 times and then a first tank and a second Tsnk one ordinary cylinder paper machine. The mass (B) was diluted 8 times and added to the third and four-tone tank of the paper machine led. The crowds (A)

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and (B) were made into a four-ply sheet, dried using a multi-cylinder dryer, and thoroughly a 5-stage machine calender and then wound up. The total weight per unit area of the obtained paper was 120 g / m "and the thickness was 0.125 mm.

A low density polyethylene (Suraikathene L-402, manufactured by Sumitomo Chemical Co., Ltd.) containing 12% by weight of titanium dioxide. (Tipaque R-820, a product of Ishihara Sangyo Kabushiki Zaisha) was extrusion-drawn onto the black paper layer side of the base paper obtained above in an amount of 50 g / m 2. The extrusion coating machine contained a screw extruder with an internal extrusion diameter of 60 ram and a T-die with a width of 500 mm, the coating speed being 30 mm per minute. The surface of the chill roll on which the resin was poured was finished with a matt finish. On the other hand, the titanium dioxide; Containing polyethylene drawn onto the side of the white paper layer of the base paper in a thickness of 0.045 ram using the same extrusion coating machine, but using a cooling roller with a smooth surface. Thereafter, the paper was a Koronaentladungbei 250 \ ϊ using a corona discharge device (product of Lepel Company) subjected to the distance between the electrodes was 8 ram. The carrier obtained thereby had excellent water fastness, dimensional stability and writing properties.

Coating the carrier with a panchromatic silver jodbroroid gelatin emulsion containing 2 mol% of iodine gave a fog of only 0.10 after it had been exposed from the rear surface for 10 seconds under direct sunlight. V / enn however the env.il & ion on an ordinary ": θ Boryt paper with a green i, ^f ; ο weight vo ^

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210 g / m 2 was drawn up, resulted in the photographic image obtained Paper a fog of 1.80 under the same conditions. The back surface of the one obtained in this example Carrier - could be made with a pencil with a hardness of 2B.

Example 2

20 parts by weight of zinc oxide, 10 parts by weight of cellulose triacetate, 40 parts by weight of acetone and 80 parts by weight of methyl dichloride were mixed well in a ball mill and the mixture obtained on both surfaces of the light-shielding base paper, obtained according to Example 1 to a thickness after drying of 0.02 mm using a reverse roll cover coated at a speed of 10 m per minute. On the surface of the resin layer On the side of the black paper layer, a coating solution: 10 parts by weight of Aerosil 200 (product of Japan Aerosil Co. Ltd.), 5 parts by weight gelatin, 50 parts by weight Methanol, 3 parts by weight of Via ss er, 30 parts by weight of acetone and 30 parts by weight of methylene dichloride in an amount of 2 g / m drawn up using an air spread coating device. The surface of the resin layer on the white paper layer side was exposed to 5 ultraviolet irradiation tubes of 1 KW, which were at a distance of 50 mm from the surface, treated and then with a Coated sub-soaking solution, which consists of 3 parts by weight of gelatine, 50 parts by weight of methanol and 5 parts by weight of ethylene dichloride existed, namely in a thickness of about 0.001 ram after drying.

A silver chlorobromide gelatin emulsion containing 40 molar bromine (weight ratio of silver halide to gelatin 1: 3) was on the carrier obtained in one

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Amount of 4 g / m, calculated as Ag, absorbed.

A white Wolfrain lamp of 100 W was irradiated on the rear surface of the obtained photographic material from a height of 1 ra for 5 minutes, but no fogging occurred. The carrier showed good light-shielding properties. Furthermore, the carrier hardly absorbed the processing liquid during development. The time required for drying the photographic material treated in this way in warm air of 30 ^° C. was about 1/10 of the time required for a photographic paper based on baryta paper.

Example 5

A panel dispersion of 5 wt .- ^ of 50 parts of bleached sulfite pulp of Coniferenbäumen and 50 parts of "unbleached kraft pulp from broad-leaved trees was passed through a refiner disc-type and geholländert ⁰ SR to a 'level 45 of-. With the obtained paper pulp was $ 5 Kayaku Direct Past Black D (product of Nippon Kayaku Kabushiki Kaisha), 3 % sodium stearate, $ 3 aluminum chloride, and 0.8 % Kymene-557 (product of Hercules Powder Company), all percentages being based on the dry weight of the pulp , mixed successively to prepare pulp (A) Separately, pulp (B) was prepared from the same ingredients except for Kayaku Direct Past Black D.

The pulp (A) was diluted about 5 times and fed into the second tank of a cylinder paper machine and the pulp (B) was diluted about 6 times and put into the first and third tanks of a paper machine guided. A three-layer base paper was produced. The total unit weight of the raw paper was 100 g / m 2 and the thickness was 0.15 mm.

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A water-dispersible coating solution of 15% by weight polyvinylchloride emulsion, 10% by weight polyvinylidene chloride emulsion and $ 20 wt .- Lithopone was applied to both Pages of the raw paper obtained with a thickness of 0.02 mm after drying using a strip sheet winding device applied and then dried.

An aqueous dispersion was put on the surface of the light-shielding support thus obtained raised, the 10% by weight silica colloid (Snowtex 20, product from Nissan Chemical Co., Ltd.) and 1% by weight sodium sulfide contained in an amount of 1 g / m as dry weight,

and then dried. The obtained product was used as a positive material for the silver salt diffusion transfer photography method used. The diffusion transfer was from a negative with a sensitivity of ASA (Neopan SS, a product of Fuji Photo Film Co., Ltd.) using of a developer for application to the Polaroid Land Pilm type 107 under direct sunlight.

The transmission density was increased by the appearance of Fog not decreased.

The obtained photographic paper showed an elongation of at most 0.05 % or less even when it was kept at room temperature and the relative humidity was changed from $ 20 to 90 #. This represents a marked improvement in dimensional stability in view of the fact that ordinary photographic papers exhibit an elongation of about 0.5 ° / ° in a direction perpendicular to the direction of arcing when exposed to such conditions.

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Claims (7)

Claims (j. Photographic support containing a base paper composed of a light-shielding black paper layer and a white paper layer on at least one surface of the black paper layer "produced together in the sheet forming process, and water-resistant synthetic resin layers on both surfaces of the base paper. 2. Photographic support according to claim 1, characterized in that the synthetic H ₃ resin layer contains a polyolefin, cellulose acetate, polyethylene terephthalate, polyvinyl chloride, polyvinyl acetate or copolymer of styrene and butadiene as a compound of high molecular weight. 3. Photographic support according to claim 1 or 2, characterized in that the thickness of the resin layer Is 0.005 mm or more. 4. Photographic support according to Claims 1 to 3, characterized in that the resin layer is a white pigment Contains titanium white, zinc oxide, zinc sulfide or lithopone. 5. Photographic support according to Claims 1 to 4, characterized in that that surface of the resin layer those in contact with the photographic emulsion should come, a surface activation treatment, for example ultraviolet radiation, corona discharge or Is subjected to flame treatment and / or is covered with an undercoat layer. 6. Photographipcher carrier according to claim 1 to 5, characterized in that the black paper layer contains carbon black or a dye. BATH ORIGINAL 2 09822/0 8 30 7. Photographic layer according to claim 1 to 6, characterized in that the white paper layer is used as a white pigment titanium white, clay, barium sulfate, or lithopone Contains zinc sulfide. 209822/0830