PROCESS FOR THE MANUFACTURE OF A REINFORCED SEMIPERMEABLE MEMBRANE TUBE

• Main Authors: STOELTING K, SCHWARZER F
• Format: Patent
• Language: English
• Published: 19.06.1973
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PROCESSES FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TOSURFACES, IN GENERAL; PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCESIN A PLASTIC STATE; SEPARATION; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; SPRAYING OR ATOMISING IN GENERAL; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

1280068 Semi-permeable membrane tube KALLE AG 8 June 1970 [9 June 1969] 27537/70 Headings B1X and B2E [Also in Division F2] A reinforced semi permeable membrane tube is made by a process comprising conveying a coherent web 1 of permeable material downwardly and simultaneously continuously forming it into a tube with a longitudinal seam, for example by means of folding devices 3 which fold the material around the outside of die tube 5b, applying a layer of a solution of a film-forming substance to the inside of the formed tube, for example through annular die 5, evaporating part of the solvent from the layer and precipitating the film forming substance from the remaining solution in the layer. Evaporation of solvent from the film may be controlled by introducing air or solvent-containing air into the tube through pipe 8. The precipitating agent 12 for the filmformer may be both inside and outside the tube. In the embodiment shown, web 1 is of paper, the coating solution comprise cellulose acetate and the precipitating liquid is water. The finished tube is collapsed as it passes over pulley 15 and is reeled at 16. Other web materials mentioned are fibre fleece, natural or synthetic fibre fabric or perforated plastics film. There is a reference to using the finished tube in perforated sheet metal vessels.