Eastman-kodak Company

Other

Bruce S Gowans

Christopher B Rider

Nicholas J Dartnell

David A Skye

An electrolytic cell for the recovery of silver from a photographic fixer solution has a cylindrical cathode secured to and depending downwardly from a screw-on lid of the cell into the solution. The cathode is formed from a sheet of graphite foil laminated to a polyester base, and is clamped at its upper periphery around a boss of the lid. A metal connection ring is embedded around the outer periphery of the base and is contacted by the cathode. This arrangement is particularly suitable for allowing a thin, flexible disposable cathode to be conveniently removed from the cell by means of the lid, without the user being exposed to contact with the silver or with the solution.

Apparatus for recovering metal from solution

A system and method are provided for the safe removal of a wet, fully-plated cathode from a silver recovery cell and its replacement by a fresh cathode. The fresh cathode is brought to the recovery cell in a transport housing, which is then docked thereto. A drip tray is unfolded from the transport housing so as to extend across and surround the top of the recovery cell. The fresh cathode is removed from the transport housing and put to one side. The used cathode is removed from the recovery cell, preferably by being attached to the lid which is unscrewed therefrom. The cathode is then transferred to the housing over the drip tray which catches any liquid falling therefrom. The used cathode is screwed into the transport housing, and the housing removed to a refiner for safe disposal, whilst the fresh electrode is screwed onto the recovery cell.

System for, and method of, removing a component from immersion in a liquid

An electrolytic cell for the recovery of silver from a photographic fixer solution is of generally cylindrical configuration. The cell has a screw-on lid that carries the disposable cathode of the cell. Inlet and outlet for the solution are at the bottom of the cell. The anode is tubular and extends upwardly from the outlet at the base of the cell towards the lid. The cathode is easily replaced, together with the lid, and flow through and the dimensions of the cell are arranged to avoid entrapment of gas therein.

Electrolytic cell

A processed sheet of photographic film is guided into a channel of scanning equipment in which it is subjected to light from an elongate fluorescent tube. Light transmitted through the film is detected by a sensing arrangement in the form of an elongate solar cell strip. The strip is scored so as to divide it into 3 small subsidiary sensors and four longer sensors. All seven sensors form the main light sensor. As the leading edge of the film, which is assumed to be of uniform light density, enters the channel and totally obscures at least one of the subsidiary sensors, that sensor measures the transmittance of the film. This value, together with the reduction in light sensed by the main sensor, is then used to determine the width of the film. The film width is combined with the separately computed film length, to provide a signal used to control the amount of replenishment chemicals to be supplied to a photoprocessor.

Width measurement of an image-bearing sheet

Recovery of silver from a photographic fixer solution in an electrolytic cell is controlled so as to maintain a high current efficiency whilst minimizing unwanted side effects. The rate of change of plating voltage at constant current through the cell is monitored, and in response to detection of a maximum value thereof the current is reduced to a new constant level. Such control allows the cell to be operated continually at high current efficiency in response to changing chemical conditions within the cell.

Recovery of metal from solution

A system and method are provided for the safe removal of a wet, fully-plated cathode from a silver recovery cell and its replacement by a fresh cathode. The fresh cathode is brought to the recovery cell in a transport housing, which is then docked thereto. A drip tray is unfolded from the transport housing so as to extend across and surround the top of the recovery cell. The fresh cathode is removed from the transport housing and put to one side. The used cathode is removed from the recovery cell, preferably by being attached to the lid which is unscrewed therefrom. The cathode is then transferred to the housing over the drip tray which catches any liquid falling therefrom. The used cathode is screwed into the transport housing, and the housing removed to a refiner for safe disposal, while the fresh electrode is screwed onto the recovery cell.

Growing community of inventors

Hemel Hempstead, United Kingdom

Bruce S Gowans