Abstract:
A method for modifying the transfer characteristics of a porous organic or inorganic membrane, wherein (a) at least one layer is formed on the membrane by applying at least one uniform solution prepared by mixing one or more rare earth or alkaline-earth fluoroalkoxides with an anhydrous organic solvent at room temperature and in an inert atmosphere; (b) hydrolysis is performed by contacting the layer of (a) with an amount of water at least as great as the stoichiometric amount needed to hydrolyse the fluoroalkoxides; and (c) rinsing the membrane with water to remove the resulting soluble salts. The resulting modified membranes are useful for regenerating photographic solutions, particularly black and white developers, and for separating organic compounds from aqueous effluents.
Abstract:
The invention relates to a machine tool support. The support according to the present invention comprises a fixed frame (10), suction means, a source of compressed air, a bearing structure (13) comprising a plate (11) provided with holes (14) and means (12) intended to absorb the vibration generated by the operation of the machine and/or by its environment. According to the present invention the said holes (14) can communicate selectively with the suction means or the source of compressed air. In addition, the machine rests directly on the surface of the said plate (11), a means (12) suitable for absorbing the vibration being disposed between the frame and the bearing structure. Application to the support of machine tools.
Abstract:
The invention relates to a surface tension sensor for a liquid flow. The device according to the present invention includes a measuring probe formed of a wettable cylinder, the cross section circumference of which does not exhibit any concave portion and the distance of which between the isobaricenter of the cross section and any point on the circumference is less than 3 mm, the ratio between the maximum distance of a point on the circumference to the isobaricenter and the minimum distance of a point on said circumference to the isobaricenter being less or equal to 2. Application to the surface tension measuring of photographic compositions on a photographic coating device.
Abstract:
The invention relates to a method for the continuous preparation of vanadium pentoxide gel and an apparatus for implementing the method. According to the present invention, the vanadium pentoxide is raised to a temperature at least 100 °C higher than its melting point; it is poured continuously into a quenching reactor (2) containing distilled water at ambient temperature; the gel obtained flows by overflowing to an ageing reactor (4), the contents of which are recirculated to the quenching reactor; the concentration of the gel contained in the ageing reactor (4) is measured continuously so as to adjust continuously the quantity of distilled water to be added to the quenching reactor (2); the contents of the ageing reactor are evacuated into a storage drum (9). Application to the manufacture of vanadium pentoxide for anti-static applications.
Abstract:
The invention relates to the conditioning of very long photosensitive webs. The magazine includes a base (10) appropriate to the handling by means of a lift truck, a lighttight case (20) formed of two parts (210, 211) each exhibiting a lip (220, 221) defining slots allowing to extract the photosensitive material. According to the invention, the core axis is maintained substantially horizontally by means of series of support-rollers (30) arranged under the rolls of photosensitive material. Application to the photographic paper supply.
Abstract:
A method for preparing a photographic emulsion incorporating tabular silver halide grains is described. It is characterized in that twinned silver halide nuclei are precipitated either in an external static nucleator operating under laminar conditions with a Reynolds number of less than 2100, or in a recipient with a very low agitation speed compared with that normally used, and characterized also in that the concentration of the Ag+ ion solution is between 0.04 and 0.3 M. Tabular silver halide grains are obtained with a diameter distribution lower than 15 %.
Abstract:
A method for desilvering photographic effluent by electrolysis uses an electrolyser unit comprising at least one anode compartment and at least one cathode compartment. The photographic effluent is treated in the cathode compartment of the unit to reduce the silver ions in solution. The electrolyte is then recycled in the anode compartment before being discharged. Recycling in the anode compartment reduces the silver content of the discharged effluent to below 20 ppm.
Abstract:
The cutting device described is characterized in that the tools (2-5) used for cutting and forming the rounded corners are driven by two double eccentrics (6, 7), the first double eccentric (6) driving the blade (2) by means of a first eccentric and positively driving the two stamps (4) by means of a second eccentric, the first and second eccentrics being 180° out of phase, the second double eccentric (7) driving the counter blade (3) by means of a third eccentric and positively driving the two dies (5) by means of a fourth eccentric, the third and the fourth eccentrics being 180° out of phase.
Abstract:
A packaging for light-sensitive strips is described. The packaging comprises a base (10) designed for handling by fork lift trucks, a slot (60) defined by an upper lip (66) and a lower lip (67), a rod (30) rigidly connected to the base (10) via a frame (40), and a wrapping (20) to protect the photographic materials. The rod includes several separate locking elements (70) for selectively allowing the light-sensitive strips (68) to be removed. The packaging can be used for supplying photographic printers.
Abstract:
The invention concerns a device making it possible to prevent any relative travelling movement in a first plane between two components moving in relation to each other in a second plane substantially perpendicular to the first. The device comprises two bars P1P4, P2P3 interlinked at the mid-point by a pivot point C, where one of the ends of said two bars is integral with the first component at a pivot point P1 and a pivot-slide point P3, while the other end of the bars is integral with the second component at a pivot point P2 and a pivot-slide point P4, the pivot and pivot-slide points consisting of flexible portions of said bars. Application to movement in strip embossing, pricking, cutting, perforating machines.