The insertion of elastic threads can be complex and costly in the manufacture of hygiene products. Herrmann Ultraschalltechnik has developed a novel patented method for fixing elastic threads that, among other things, simplifies handling and reduces the risk of breakage.
The innovative process creates a tunnel between the 2 layers of nonwovens in which the stretched elastic thread is guided. By using ultrasonics specific bonding areas are created in which the thread is partially anchored, and after cutting the product the thread relaxes and is clamped by the weld spots. Easy positioning of multiple threads is another advantage of this development.
This new anchoring process from Herrmann Ultraschalltechnik GmbH & Co.KG, Karlsbad/Germany, can be executed intermittently or continuously. Further innovations in controlling the signal of the ultrasonic generator Ultrabond allow for “triggering” the ultrasonic energy very fast in the right places. Thus format-dependent tools are no longer needed. The standardized ultrasonic tools (sonotrodes) in the Microbond CSI system offer proven Microgap technology. Multi-dimensional process monitoring is possible by combining it with the generator signal.
This new fixation process called Anchoring, offers multiple advantages over gluing, e.g. softer touch, controlled and repeatable process with high production speeds and wide web widths, very good creep performance and splice processing, and better stretch performance of threads as they are not exposed to any heat during the process.