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US 4,359,518 AGranted
Stripping sheet for use with diffusion transfer film unit
AssigneePolaroid Corporation
InventorsRaymond B. Hanselman, Karl J. Schreiber
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Abstract
A stripping sheet adapted for use with a diffusion transfer film unit to remove at least the photosensitive layer from said film unit subsequent to processing is disclosed, as well as methods for using said stripping sheet, wherein said stripping sheet comprises a support, carrying in order, a water-absorbing layer, and a layer capable of conversion from substantial liquid processing composition impermeability to a condition of substantial liquid processing composition permeability.
Claims22
A method which comprises the steps
- (a) exposing a diffusion transfer film unit comprising a support carrying, in order, an image-receiving layer, and a photosensitive silver halide emulsion layer;
- (b) disposing a liquid processing composition intermediate a stripping sheet and the outermost layer of said film unit distal to the support;
- (c) contacting said outermost layer of said film unit distal to the support with said stripping sheet wherein said stripping sheet comprises a support carrying, in order, a water-absorbing layer and a timing layer capable of conversion from substantial liquid processing composition impermeability to a condition of substantial liquid processing composition permeability;
- whereby said timing layer converts from said substantial liquid processing composition impermeability to said substantial liquid processing composition permeability thereby forming a bond between said outermost layer and said stripping sheet;
- and
- (d) detaching said stripping sheet and at least the photosensitive layer of the film unit adhered to said stripping sheet from the rest of the film unit.
3 more elements
Dependencies are inferred from the claim text.