Method of activating a protective layer on a photographic element employing an organic solvent in the wash solution
AssigneeEastman Kodak Company
InventorsThomas H. Whitesides, Amy E. Jasek
Life of this patent
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Abstract
The present invention is a method of forming a protective overcoat on a photographic element which element includes a processing-solution-permeable overcoat that becomes water-resistant in the final product without lamination or fusing. The method involves the incorporation of a small amount of a water-soluble organic solvent in the last step of the photographic process, i.e., during the washing step. This method allows the use of durable water-resistant protective overcoat materials with relatively high glass transition temperatures, that normally do not convert to impermeable films at low temperature, or without fusing.
Claims15
A method of making a photographic imaged element comprising:
- (a) providing an imagewise exposed photographic imaging element comprising a support, at least one silver-halide emulsion layer superposed on a side of said support, a processing-solution-permeable precursor-protective layer overlying the silver-halide emulsion layer, said protective-precursor layer having a laydown of at least 0.54 g/m2 (50 mg/ft2) made from a coating composition comprising 30 to 95%, by weight of solids, of water-dispersible polymer in the form of particles having an average particle size of less than 500 nm, and 5 to 70%, by weight of solids, of water-soluble polymer such that more than 30 weight percent of the water-soluble polymer is washed out during photographic processing, wherein the weight ratio of water-dispersible polymer to water-soluble polymer is between 50:50 to 90:10;
- (b) developing the photographic element in a developer solution having a pH greater than 7 to obtain a photographic imaged element;
- (c) washing the developed photographic imaged element in a wash solution comprising a water-soluble organic solvent;
- and
- (d) drying the washed photographic imaged element of (c), in which an effective amount of the water-soluble organic solvent has been retained, in order to convert the layer with the water-dispersible polymer into a water-resistant protective layer.
The method of claim I wherein, during drying, the photographic imaged element is substantially maintained at a temperature less than 100° C. and no fusing is employed.
Dependencies are inferred from the claim text.