A process for enhancing the pleatability of a meltblown web and a process for pleating a meltblown web

摘要

A process for enhancing the pleatability of a meltblown web (10) uses ultrasonic bonding wheels (18) to create bond lines (20) in the machine direction (12) as the web (10) is being produced. In addition to, or in place of, the bond lines, ribbons (30) made of the web material, a thermoplastic polymer, string saturated with a phenolic or ultraviolet curing resin, or beads of an ultraviolet curing resin may be ultrasonically bonded to the web (10) to enhance its stiffness. A heated scoring bar (25) or ultrasonic horn forms pleats in the web (10) by heating the web (10) above its glass transition temperature and deforming the web (10) into the pleated configuration. Cooling of the web (10) locks the pleats into position.