Abstract:
A process is disclosed for coating the inside surface of a length of tubing comprising the steps of forming at least one loop of tubing with a downwardly inclined portion and an upwardly inclined portion; filling the cavity of the tubing forming the loop with a coating liquid; transporting the tubing along its longitudinal axis in a substantially vertically upward direction to coat the inside of the tubing above the level of the coating liquid with an initial layer of coating liquid; constricting the tubing adjacent to and above the level of the coating liquid along a constriction zone transverse to the longitudinal axis of the tubing, the constriction zone progressively diminishing in width in the direction of travel of the tubing to reduce the thickness of the initial layer and form a thin layer of desired thickness on the inside of the tubing issuing from the constriction zone; filling the cavity of the tubing issuing from the metering device with support gas; and exposing the tubing to heat at a sufficient temperature to fuse the coating layer to the inside of the tubing and form an uninterrupted film of uniform thickness thereon. The coating liquid can comprise an aqueous polymeric dispersion containing at least about 15% by weight of dispersed polymer based on the total weight of the dispersion and preferrably in the range of about 15 to 60% by weight. Also disclosed is an apparatus for carrying out the process of the present invention.
Abstract:
A porous shaped article, especially a flat shaped sponge like article, in particular a sponge cloth, is disclosed which exhibits an improved cleaning effect and which comprises cellulose hydrate and from about 10 to about 80% by weight of polyolefin fibrids.
Abstract:
A porous shaped article adapted for medicinal use is disclosed which comprises a porous regenerated cellulose the entire surface of which is covered with a coating comprising a hydrophilizingly effective amount of at least one wetting agent and a substantially water insoluble chemically modified cellulose ether which is crosslinked carboxymethylcellulose or a reaction product of a partially etherified cellulose and a chemical modifying agent which is capable of reacting with the free hydroxy groups of the etherified cellulose.The articles are coated by first impregnating same with a cellulose ether solution and then treating the impregnated article with a solution of the modifying agent. The wetting agent may be added to either of these steps.The coated articles retain a high absorption capacity for liquids, yet do not release any substantial amounts of turbidifying impurities into a surrounding liquid and therefore are especially suited for medical uses.
Abstract:
Disclosed is a process for coating the inside of a length of tubing comprising the steps of forming at least one loop of tubing with a downwardly inclined portion and an upwardly inclined portion; filling the cavity of the tubing forming the loop with a coating liquid; transporting the tubing along its longitudinal axis in a substantially vertically upward direction to coat the inside surface of the tubing above the level of the coating liquid with an initial layer of coating liquid; constricting the tubing adjacent to and above the level of the coating liquid with a metering device having a constriction zone which flattens a portion of the tubing passing therethrough to substantially eliminate all of the initial layer thereon and partially flattens the remaining portion of the tubing to allow a desired quantity of coating liquid to remain on the tubing issuing from the constriction zone; filling the cavity of the tubing issuing from the constriction zone with support gas; and, exposing the tubing to the action of heat at a sufficiently high temperature to fuse the coating layer to the inside thereof and form an uninterrupted film. Also disclosed is an apparatus for carrying out the process.