Verfahren zum UEberziehen von gegenueberliegenden Oberflaechen eines Traegers fuer photographische lichtempfindliche Elemente

摘要

1,190,790. Photo-sensitive laminates. FUJI SHASHIN FILM K.K. 28 Dec., 1967 [28 Dec., 1966], No. 58941/67. Heading B5N. A method of coating the opposite surfaces of a continuously travelling web 1, for preparing a photographic light-sensitive element, comprises applying photographic coating compositions to smooth continuously moving surfaces of two cooling members, e.g. surfaces 3, 31 of members 8, 81, positioned at opposite sides of the web to provide on each of said surfaces a uniform layer or layers having the desired thickness and layer structure, cooling the layers thus formed to effect gelling, stripping the gelled layers, e.g. 4, 41, from the cooling surfaces, and adhering the stripped layers to the opposite surfaces of the web. In one embodiment, Fig. 1, the web 1 is a film base or baryta-coated paper, and the layers 4, 41 are applied simultaneously thereto from cooling drums 8, 81, to which they have been applied as coating compositions from hoppers 2, 21. The web 1 may travel more quickly than the surfaces of the drums 8 and/or 81 so that the layers 4 and/or 41 are stretched and thinned down in the zones 5, 51 before application to the web. To improve adherence between the layers 4, 41 and the web 1, the layers or the web may be heated by high-frequency or infra-red heating or by hot air before the layers are joined with the web. In addition air jets are applied in the zones 5, 51 to press the layers against the web. Means may also be provided whereby the atmospheric pressure between the web 1 and the layers 4, 41 is reduced in zones 5, 51. In a second embodiment, not shown, two layers of silver bromide solution, and a layer of aqueous gelatine solution are applied from a hopper to the surface of a cooling drum and are gelled thereon. The gelled layers are then applied to a film base travelling between the cooling drum and an auxiliary roller while stretching the layers to 1/3 of their original thickness. The coated film base then passes between a second auxiliary roller and a second cooling drum from which its uncoated surface receives an unstretched gelled layer of an aqueous gelatine solution and dye. During such passage the surface of the film base coated first is prevented from contacting the surface of the second auxiliary roller by an air cushion.