DUKANE // Ultrasonic Welding and Cutting // Film&Fabric

Processing Techniques

Ultrasonic Bonding

Ultrasonic bonding assembles two or more layers of materials by passing them between a vibrating horn and a rotary drum (often referred to as ananvil). The rotary drum is usually made from hardened steel and has a pattern of raised areas machined into it.  The high frequency mechanical motion of the vibrating horn and the compressive force between the horn and the rotary drum create frictional heat at the point where the horn contacts the material(s). The frictional heat bonds the material together only at the horn/material contact points. This gives the bonded material a high degree of softness, breathability and absorption. These are the exact same properties which are critical for hospital gowns, sterile garments, diapers and other applications used in the medical industry and clean room environments.

Ultrasonic bonding requires far less energy than thermal bonding which uses heated rotary drums to bond materials together. As a result, ultrasonic bonding is economical and requires no consumables, adhesives or mechanical fasteners.


Ultrasonic Slitting

When a thermoplastic material is slit ultrasonically, its edges are also sealed. Sealing the edges of a woven fabric is beneficial because the yarns are prevented from unraveling and the smooth, beveled edges prevent buildup of the roll material. When two or more layers are ultrasonically slit together, the layers will become joined. The strength of the bond is determined by the material and anvil geometry.

Many factors influence the speed at which fabric can be ultrasonically slit. Some of the parameters are the geometry of the cutting wheel (anvil), the material composition, material weight and thickness.

Ultrasonic Plunge

In the plunge method, the material remains in a fixed location and is periodically contacted by the horn. The horn operates perpendicular to the material that is on the anvil. The horn can also be used to cut and seal. Typical plunge applications include but are not limited to: Filters | Strapping | Vertical Blinds | Bra Straps | Belt Loops | Buckles | Embossing | Hook and Loop.

Rotary Sealing

Dukane's Rotary 30kHz Ultrasonic Sonotrode (Horn) is ideal for sealing thin films and non woven materials. The unit can be easily integrated into automation. The Rotary horn design eliminates drag issues associated with conventional static ultrasonic sonotrodes. Ultrasonic bonding is a greener solution than conventional heat sealing as power consumption is greatly reduced, requires no adhesives and produces no smoke or fumes. Applications for the rotary horn include film sealing for packaging machines, bonding of nonwoven materials and many others.



Film & Fabric bonding, slitting and sealing

Fabric & film processing is the bonding, slitting, or sealing of fabrics and films containing thermoplastic material(s). Typical thermoplastic materials found in fabrics and films include acrylics, nylon, polyester, polyethylene, polypropylene, polyvinylchloride, and urethane. Products from the textile, apparel, nonwovens, packaging, medical and automotive industries all benefit from the fast, clean, and economical fabric & film processing techniques. 


You may not realize it, but ultrasonic film applications are all around you everyday.
  • mattress pads
  • seat belts
  • rainwear
  • tamper-proof seals
  • carpet backing
  • blister packs
  • disposable medical garments
  • juice cartons
  • outdoor furniture
  • bottle cap liners
  • automotive applications

Fabrics and films used in the nonwoven, medical, filtration, textile and packaging industries can be processed using ultrasonic energy. Several of the common techniques applied are ultrasonic rotary/continuous bonding, ultrasonic slitting, plunge and traversing.


Ultrasonic Welding - Film & Fabric




Many factors influence the weldability of the various fabric and film types.


Fabrics - Woven

Formed by the regular interleaving of filaments or yarns, in two directions perpendicular to one another

Factors Influencing Weldability
Thread density, tightness of weave and uniformity of material thickness. Weld strength may vary due to the perpendicular orientation of filaments or yarns.


Fabrics - Nonwovens

Formed by bonding and/or interlocking fibers, yarns or filaments by mechanical, thermal or solvent means.

Factors Influencing Weldability
Uniformity of material thickness and thermoplastic content. The random orientation of fibers gives nonwovens excellent strength.


Fabrics - Knits

Formed by interconnecting continuous loops of filaments or yarns

Factors Influencing Weldability
Thermoplastic content, style of knit and elasticity of material. Elasticity of knits may affect the trueness of the weld in continuous processing resulting in a scalloped effect.


Fabrics - Coated Materials

Fabrics and films covered with a layer of thermoplastic such as polyethylene or urethane. The base material need not be thermoplastic (e.g. coated cardboard)

Factors Influencing Weldability
Coating material and its thickness


Fabrics - Laminates

Fabrics and films consisting of two or more dissimilar layers in a sandwich form.

Factors Influencing Weldability
The mating surface should have a lower melting temperature than the other layers.



Formed from the thermoplastic material which has been cast, extruded or blown into a film, generally under 0.01 inch (0.25mm) thick.

Factors Influencing Weldability
Film thickness, density and thermoplastic material characteristics.