Abstract A photographic film unit comprising all of the materials, including a liquid processing agent, required to produce a photographic print and a method of rapidly spreading a viscous liquid processing agent in a continuous uniform layer between a pair of superposed sheets without entraining air in the liquid. A film unit is disclosed comprising a photosensitive sheet and a transparent sheet secured in face-to-face relation at the edges of the sheets and a collapsible container of a viscous processing liquid secured at one edge of the sheets so as to discharge its fluid contents between the sheets when compressive pressure is applied to the container. A method is disclosed in which the sheets are held in face-to-face contact to exclude air from between the sheets during spreading of the processing liquid therebetween facilitate spreading and to preclude entrainment of air in the liquid.
A photographic film unit as defined in claim 1 wherein the said binding means provide a seal completely around the periphery of said air-free region in which said liquid is spread for preventing admission of air between said sheets into said region.
Claim 2
Independent Claim
250 words
The method of rapidly spreading a viscous photographic processing liquid in a continuous, uniform layer between a pair of superposed photographic sheets without entraining air in said liquid, said method comprising: superposing said sheets in face-to-face contact throughout substantially the entire area of their facing surfaces so as to exclude substantially all air from a region between said sheets extending to the edges of at least one of said sheets; progressively applying compressive pressure to a collapsible container of said liquid attached to the exterior of said sheets at one edge thereof to generate hydraulic pressure within said liquid in said container to force said liquid into said region between said superposed sheets at said one edge thereof; continuing the progressive application of compressive pressure to said sheets for advancing said liquid as a mass toward said opposite edge of said sheets to separate said sheets in a region thereof immediately ahead of said mass of said liquid and spread said liquid in a layer between said sheets; and during advancement and spreading of said liquid, sealing said sheets together at their lateral marginal edges extending in the direction of advancement and spreading of said liquid, to prevent admission of air between said sheets and escape of said liquid from between said sheets at said lateral marginal edges, and maintaining transverse portions of said sheets immediately ahead of said mass of liquid in face-to-face contact to prevent entrainment of air in said mass of liquid being advanced between said sheets.
Claim 3
Dependent Claim
63 words
A method of rapidly spreading a viscous photographic processing liquid between a pair of superposed sheets as defined in claim 3 wherein compressive pressure is applied to a transverse portion of said superposed sheets immedIately ahead of said mass of liquid being advanced between said sheets to retain said transverse portion of said sheets in face-to-face contact and prevent admission of air therebetween.