METHOD FOR OBTAINING RETAINING EDGE OF DUCK FABRICS Russian patent published in 1997 - IPC

FIELD: production of drying netted webs with retaining edge used in paper and cardboard making machines. SUBSTANCE: method involves cutting off web edge; continuously applying polymeric material to web edge. Polymeric material used in the process is melt of thermoplastic polyurethane based on ester or ether, 1,4-butanediol and 4,4-diphenyl methane diisocyanate. Admixture used in the process is fluorinated oligoester based on methanetricarboxylic acid. Melt is applied under pressure simultaneously to upper, lower and side surfaces of web so that rounded hollow polymeric chamfer is formed on side surface of web edge. Polymeric material penetrates deep into web edge material. Polymeric material is applied per unit of length of web in an amount, Q, kg/m, determined by formula recited in Specifications. EFFECT: increased efficiency, improved wear-resistance, resistance to relax and tangling of web edge. 6 cl, 4 dwg, 3 tbl