摘要:
A coating device for coating a peripheral surface of a sleeve body with a coating formulation includes a vertical support column for supporting a sleeve body in a vertical position coaxial with a coating axis, a carriage slideable along the vertical support column, and an annular coating stage attached to the carriage and moveable therewith for containing the coating formulation and for coating a layer of the coating formulation onto the peripheral surface of the sleeve body during a sliding movement of the carriage along the vertical support column. The coating device includes an irradiation stage that is arranged to be moveable with the annular coating stage and to provide radiation to at least partially cure the layer of coating formulation onto the peripheral surface so as to prevent flow off of the coating formulation.
摘要:
A method is provided for applying a magnetic layer onto a polymeric sheet or web material comprising the steps of(i) simultaneously coextruding a non magnetic "dummy" layer and a magnetic layer onto said polymeric sheet or web material, said non magnetic "dummy" layer being closest to the support(ii) drying the coextruded layers characterised in that the sum of the wet coating thickness of said "dummy" layer (Th.sub.dum) and of the wet coating thickness of said magnetic layer (Th.sub.mag) fulfils the equation 25 .mu.m.ltoreq.Th.sub.dum +Th.sub.mag .ltoreq.100 .mu.m and that the ratio of (Th.sub.mag) to (Th.sub.dum) fulfils the equation 0.01.ltoreq.Th.sub.mag /Th.sub.dum .ltoreq.1.
摘要:
A curtain coater and coating method for coating a moving web with at least one layer of a liquid coating composition utilizes a web-supporting roller for conveying the web along a path, a coating hopper for forming a free falling generally planar curtain of the coating composition which extends transversely of the web and impinges upon the web at a point on the path where the web is supported on the roller, edge guides on opposite sides of the web path for laterally guiding the falling curtain by contact with the curtain side edges, and a curtain intercepting member is occasionally displaceable from an inoperative position out of the path of the falling curtain to an intercepting position adjacent the web for intercepting the falling curtain, wherein the intercepting member has a dimension transversely of the web that is greater that the transverse dimension of the web itself and a portion of each of the edge guides adjacent to the web is displaceable independently of the coating hopper away from the web to a position removed from the web, preferably out of the plane of the falling curtain, and out of the way of the intercepting member to allow the intercepting member to take its intercepting position, and when the intercepting member is moved to inoperative position, each edge guide portion is returned to its position adjacent the web.
摘要:
A coating device for coating a peripheral surface of a sleeve body with a coating formulation includes a vertical support column for supporting a sleeve body in a vertical position coaxial with a coating axis, a carriage slideable along the vertical support column, and an annular coating stage attached to the carriage and moveable therewith for containing the coating formulation and for coating a layer of the coating formulation onto the peripheral surface of the sleeve body during a sliding movement of the carriage along the vertical support column. The coating device includes an irradiation stage that is arranged to be moveable with the annular coating stage and to provide radiation to at least partially cure the layer of coating formulation onto the peripheral surface so as to prevent flow off of the coating formulation.
摘要:
A photographic material comprising a transparent film support having on one side at least one light-sensitive layer and on the other side a transparent magnetic layer and an antistatic layer of a polythiophene arranged above or below said transparent magnetic layer shows transparency and good mechanical and antistatic properties.
摘要:
Disclosed are seamless membrane bags, for example, a membrane bag comprising a spacer fabric and a volume for permeate collection, the spacer fabric comprising a first part and a second part that are spaced apart and tied together at a predefined distance by monofilament thread and the first and second parts are at least partially embedded with membrane substance and the volume for permeate collection is interposed between the first and second parts. The membrane substance embeds portions of the monofilament thread and fills the spacer fabric along the border of the membrane bag. The membrane substance completely enclosing the volume is seamless. Also disclosed are processes for producing such bags, a filtration unit comprising such a membrane bag, and their uses in the separation of fluids, vapors and particles.
摘要:
Process comprising the steps of: (i) providing an elongated porous web, said elongated porous web comprising two outermost surfaces; (ii) transporting said elongated porous web downwards between two impregnating heads comprising two slots each with substantially vertical upper and lower slot faces substantially parallel to said elongated porous web providing simultaneously to both surfaces of said elongated porous web metered substantially identical quantities of a dope, comprising at least one membrane polymer and at least one solvent therefor; (iii) thereby impregnating said elongated porous web completely with said dope and providing substantially equally thick dope layers on each surface of said outermost surfaces of said elongated porous web with a thickness independent of the gap between one of said lower slot faces and the surface of said elongated porous web nearest thereto; (iv) subjecting said dope associated with said elongated porous web immediately after dope-impregnation to symmetric phase inversion with at least one non-solvent thereby forming a membrane; and (v) removing residues of said at least one solvent for said at least one membrane polymer from said membrane thereby producing an ion-permeable web-reinforced separator, wherein said dope is shear-thinning, and the separator obtainable therewith.
摘要:
An apparatus for producing an ion-permeable web-reinforced separator comprising a duplex type impregnating apparatus comprising two slots each with substantially vertical upper and lower slot faces for providing premetered substantially identical quantities of a dope simultaneously to either side of an elongated porous web, a transport means providing for substantially vertical downwards transport of said elongated porous web through said duplex impregnating apparatus and subsequent phase inversion, coagulation and washing stations, said phase inversion station providing for phase inversion of said dope and said coagulation station providing for coagulation and washing of solvent from the resulting phase-inverted dope, wherein there is an air gap between said duplex impregnating apparatus and said phase inversion station and wherein the distance between the lower faces of each impregnating apparatus is greater than the distances between the upper faces of each impregnating apparatus; a process comprising the steps of: (i) providing an elongated porous web, said elongated porous web comprising two outermost surfaces; (ii) transporting said elongated porous web downwards between two impregnating heads comprising two slots each with substantially vertical upper and lower slot faces substantially parallel to said elongated porous web providing simultaneously to both surfaces of said elongated porous web metered substantially identical quantities of a dope, comprising at least one membrane polymer and at least one solvent therefor; (iii) thereby impregnating said elongated porous web completely with said dope and providing substantially equally thick dope layers on each surface of said outermost surfaces of said elongated porous web with a thickness independent of the gap between one of said lower slot faces and the surface of said elongated porous web nearest there-to; (iv) subjecting said dope associated with said elongated porous web to symmetric phase inversion with at least one non-solvent thereby forming a membrane, and (v) removing residues of said at least one solvent for said at least one membrane polymer from said membrane thereby producing an ion-permeable web-reinforced separator, wherein said dope is shear-thinning and steps (iv) and (v) are optionally performed simultaneously; and the separator obtainable therewith.
摘要:
A coating system for applying to a face of a moving continuous web a coating of predetermined thickness of a liquid coating composition, thereafter drying the thus-coated web under substantially constant drying condition, and collecting the dried coated web on a take-up roll, is provided with an arrangement for removing from the coating any portions exceeding the predetermined thickness which would not be completely dried during drying and would adhere to and contaminate surfaces coming in contact therewith, such as guide roller surfaces or the adjacent windings on the take-up roll. The arrangement includes web wiping means for contacting excessively thick regions of the coating which is adapted to be displaced from an inoperative position remote from the web to an operative position contacting the excessively thick regions of the coating, the displacement being actuated in response to the detection on the web of excessively thick coating regions. The web wiping means is driven in its operative position in a continuous, e.g. circular, path having a locus intersecting the web path and preferably is a cylindrical brush of flexible bristles. The removed coating portions may be cleaned from the wiping means e.g. by a scraper and aspirated away by suction.
摘要:
A curtain coater for applying a layer or film of a liquid coating composition as a falling curtain on a surface of a continuous web moving around an arc of a backing roller, has a curved air shield arranged in closely spaced parallel relation to the roller periphery extending around a segment of said periphery directly upstream of the falling curtain to define an air gap through which the web passes before reaching said curtain. At the opposite end regions of the air shield and also at opposite side regions thereof are provided means, such as projections or sections of increased thickness, for increasing the resistance to air flow in the gap at the end and side regions compared to the air flow resistance in the region of the shield intermediate the end and side regions. A suction device communicates with the gap in the intermediate region to reduce the air pressure therein. The effect of this air shield is improved removal of the boundary layer of air at the surface of the moving web prior to the coating curtain and thereby allow increased speed of the moving web.