Patent GB-734084-A (GB)
Title: Photographic film holders
IPC: G03B42/04
Filed: 1952-02-15
Abstract: 734,084. Holder for self-processing photographic film unit. INTERNATIONAL POLAROID CORPORATION. Feb. 15, 1952 [March 6, 1951; May 19, 1951], No. 4087/52. Class 98 (1). The holder has opaque front, back and side portions and a passage at one or both ends constituting a light-tight but yieldable closure whereby the film unit which includes a rupturable container of processing fluid may be drawn out of the holder by a leader strip, or may first be drawn into the holder and subsequently drawn out, without allowing access of light to the unit in the holder and without rupturing the container. The holder may have an extension beyond the light-tight closure and open to actinic light to accommodate a portion of the film unit including, particularly, the rupturable container. The front and back portions of the holder may be mounted for relative movement towards each other. The holder is particularly adapted for use in X-ray photography and may have an intensifying screen mounted in spaced relation to the front and back portions thereof, and which screen partitions the holder into two chambers for different layers of the film unit. As shown diagrammatically in Fig. 1 the holder 10 has front portion or wall 11 as of metal with an insert 15 as of plastic material rendered lightimpermeable by means of a black pigment or dye but permeable to X-rays, gamma-rays and other forms of nuclear radiation, back wall 12, light-tight yieldable closure 17 as of felt or bristles, parallel motion links 18 between the front and back walls, extensible end wall 16 and (not shown) extensible side walls 14 over the links 18, and intensifying screen 19. The holder 10 is for use as with the film unit of Fig. 2 which has liquid confining layers 21, 22 carrying, respectively, photo-sensitive surface 24 and print-receiving surface for positive image production by migratory transfer 25, rupturable processing-liquid container 26, and leader strip 23; a holder with the film unit inside being shown in Fig. 3. These assemblies would require dark-room loading and processing, after X-ray exposure of the film within the holder, processing being effected after withdrawal of the film from the holder by rupturing the container and spreading the liquid with the aid of pressure-applying elements. Figs. 6, 7 and 8 (not shown), illustrate, respectively, a holder in which both ends constitute light-tight yieldable closures; a holder with rigid, hinge-jointed surfaces; and one with end-extensions flared away from each other to form an open compartment to accommodate the rupturable container in a position outside of the light-tight yieldable closure. Figs. 10-23 (not shown) illustrate a large rigid holder as of dimensions thirteen by eleven inches and film assembly therefor for general X-ray work. The holders as more particularly described are intended for daylight loading by drawing the film assembly from a light-proof container into the holder by a leader strip, and then daylight processing by drawing the film assembly on after exposure into a processing apparatus containing pressure-applying members to rupture the container and spread the processing liquid, as further described in Specification 734,110, to produce finished negative and positive images in a time as of one minute.