COATING A WEB

• Main Authors: JOHN ANTHONY ESPOSITO, RONALD WAYNE KOCK
• Format: Patent
• Language: English
• Published: 08.01.1987
• Edition: 4
• Subjects: APPARATUS FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TOSURFACES, IN GENERAL; APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL; BANDAGES, DRESSINGS OR ABSORBENT PADS; BRAIDING; COTTON-WOOL; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF,TUBULAR STRUCTURES OF THE BODY, E.G. STENTS; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS,NON-WOVEN FABRICS; FILTERS IMPLANTABLE INTO BLOOD VESSELS; FIRST-AID KITS; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR; FOMENTATION; HUMAN NECESSITIES; HYGIENE; KNITTING; LACE-MAKING; LAUNDERING; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARYMATERIAL; MEDICAL OR VETERINARY SCIENCE; NON-WOVEN FABRICS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; PERFORMING OPERATIONS; PROCESSES FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TOSURFACES, IN GENERAL; PROSTHESES; SPRAYING OR ATOMISING IN GENERAL; TEXTILES; TRANSPORTING; TREATING TEXTILE MATERIALS BY LIQUIDS, GASES OR VAPOURS; TREATMENT OF TEXTILES OR THE LIKE; TREATMENT OR PROTECTION OF EYES OR EARS; TRIMMINGS; WADDING

Method and apparatus for substantially uniformly distributing a layer of discrete particles (10) along a predetermined portion of the uppermost surface of a moving porous web (20) so that the particles (10) occupy less than 100% of the predetermined portion of the uppermost surface of said moving web (20). The method preferably comprises the steps of (a) entraining the particles (10) into a moving gaseous stream; (b) passing the gaseous stream through a conduit (7) oriented so as to discharge the gaseous stream containing said entrained particles (10) in a direction substantially parallel to the direction of travel of the moving porous web (20); (c) mixing the particles (10) entrained in the gaseous stream inside the conduit (7) to provide a substantially uniform distribution of the particles (10); (d) discharging the gaseous stream containing the uniformly distributed entrained particles (10) from the conduit (7) adjacent the predetermined portion of the uppermost surface of the moving porous web; and (e) maintaining the fluid pressure adjacent the lowermost surface of the moving porous web (20) at a level lower than that adjacent the uppermost surface of the web (20).