Process for preparing a soft and tenacious nonwoven fabric

Abstract

Abstract A PROCESS FOR PREPARING A NONWOVEN FABRIC COMPRISING FORMING A UNIFORM MAT OF FIBERS FROM 1/2 TO 5 INCHES IN LENGTH AND FROM 0.5 TO 10 IN DENIER, NEEDLE-PUNCHING SAID MAT FROM 600 TO 6000 TIMES PER SQUARE INCH BY MEANS OF A NEEDLE LOOM PROVIDED WITH FELTING NEEDLES OF FROM NUMBER 30 TO NUMBER 46 TO THEREBY FORM A FIBER SHEET HAVING A WEIGHT OF AT LEAST 150 G./M.2 AND AN APPARENT DENSITY OF AT LEAST 0.15, IMPREGNATING SAID SHEET WITH A BONDING AGENT LIQUID COMPRISING AN ANIONIC LATEX OF A HIGH MOLECULAR WEIGHT ELASTIC MATERIAL, A NONIONIC SURFACE ACTIVE AGENT HAVING A HLB OF AT LEAST 11 AND A CLOUD POINT OF FROM 30 TO 85*C., AND, AS AN INDISPENSABLE COMPONENT, IF THERE IS NO PROTECTING EFFECT OF SAID SURFACE ACTIVE AGENT, AN IONIZABLE ORGANIC OR INORGANIC METALLIC SALT TO COAGULATE SAID LATEX, WHEREIN THE CONTENT OF SAID HIGH MOLECULAR WEIGHT ELASTIC MATERIAL IS AT LEAST 10% BY WEIGHT OF THE TOTAL WEIGHT OF SAID BONDING AGENT LIQUID, WHEREIN THE CONTENT OF SAID NONIONIC SURFACE ACTIVE AGENT IS FROM 5 TO 30 PARTS BY WEIGHT, PER 100 PARTS BY WEIGHT OF SAID HIGH MOLECULAR WEIGH ELASTIC MATERIAL, AND WHEREIN THE AMOUNT OF SAID METALLIC SALT IS SUFFICIENT TO COAGULATE SAID HIGH MOLECULAR WEIGHT MATERIAL, SO AS TO DEPOSIT FROM 20 TO 50 PARTS BY WEIGHT OF SAID HIGH MOLECULAR WEIGHT MATERIAL PER 100 PARTS BY WEIGHT OF FIBER COMPONENT; ELEVATING THE TEMPERATURE OF SAID IMPREGNATED BONDING AGENT LIQUID TO A TEMPERATURE ABOVE ITS COAGULATION TEMPERATURE TO THEREBY COAGULATE SUBSTANTIALLY ALL OF SAID HIGH MOLECULAR WEIGHT MATERIAL WITHOUT MIGRATION IN THE DIRECTION OF THE SHEET THICKNESS.

Inventors

• 👤 Tadashi Yokota
• 👤 Taizo Asai

Bibliographic Details