Dynamic laminating method and apparatus for ultrasonically bonding juxtaposed webs.

摘要

A method and apparatus for bonding together a plurality of juxtaposed webs which are subject to being ultrasonically bonded together to form a laminate as the webs are being driven forward at a relatively high velocity. The regions of the webs to be bonded are subjected to progressively increasing compressive forces while simultaneously being subjected to ultrasonic energy as they traverse an elongate portion of a predetermined path at a predetermined velocity. After the regions are ultrasonically bonded they may be subjected to another compression prior to the bonds becoming fully set upon cooling. The method may be practiced in an apparatus which includes an ultrasonic horn and an anvil which are configured and disposed to define a bonding passageway having an elongate convergent portion; and the apparatus may include a pressure roll biased towards the anvil adjacent the downstream end of the passageway. In a preferred apparatus embodiment: the anvil is a power-rotated cylinder having a relief-type bonding pattern disposed on its circumferential surface, and the face of the ultrasonic horn is so curved in the machine direction that the passageway has a convergent-divergent arcuate shape; the entrance to the passageway is sufficiently high to obviate web-splice induced jams; and the convergent portion of the passageway is preferably somewhat longer in the machine direction than the divergent portion.