As demand for thinner, softer and more sustainable designs continues to grow in the absorbent hygiene products market, ultrasonic technology is increasingly being used as an alternative to traditional bonding processes.

In general terms, ultrasonic bonding uses high-frequency sound to generate localized heat through vibration and causes thermoplastic fibers to bond together.

Typical applications in the absorbent hygiene category include ADL fixation, leg cuffs, side seams, lamination of nonwoven and film, and elastic thread anchoring, according to Torsten Eifler, global sales director, Nonwovens, at Herrmann Ultraschall. “The result: soft, skin-friendly products, high flexibility for manufacturers and a sustainable process that eliminates glue and reduces downtime,” he says.

Compared with conventional bonding methods such as hotmelt gluing, thermal calendering or sewing, ultrasonic technology offers several advantages, says Christian Unser, head of sales nonwovens at MS Ultrasonic. Because the process requires no consumables—such as adhesives, solvents or stitching thread—manufacturers can reduce material costs along with the associated logistics, storage and scrap.

Ultrasonics also lowers energy usage and CO emissions by introducing energy only at the weld zone instead of heating large rollers or ovens. Meanwhile, short process times and cold-welding tools allow high web speeds, fast start/stop and stable, reproducible weld quality, which are ideal for high-volume hygiene products. At the same time, because the tools remain relatively cool and the joining zone is finely controlled, delicate nonwovens and films are bonded without burning, discoloration or stiffness, which is critical for wearer comfort, Unser says.

In addition, the absence of hot glue, fumes and glue stringing creates a cleaner production environment with fewer unplanned stops for cleaning. Ultrasonic systems are also compatible with modern closed-loop control and Industry 4.0 concepts, supporting higher overall equipment effectiveness (OEE). “Overall, this combination reduces unit cost per article (materials, energy, maintenance, waste) while improving product quality and process reliability,” Unser adds.

Guy Gil, president of Chase Machine and Engineering, describes ultrasonics as a clean and efficient method of embossing, laminating or slitting synthetic materials. “While the initial investment in equipment is more, the long-term benefits more than pay for itself,” he says.

Thermal methods such as hot oil or electrically heated systems require an initial preheat cycle in order to bring the tooling to operating temperature. Then, while running, there is a significant amount of heat loss. “Ultrasonics is instantaneous,” Gil explains. “The operator can start and stop the equipment without the concern of overmelting the materials being processed. It is also a very clean method of laminating, as hoses or rotary unions that may leak over time are no longer needed. From a quality standpoint, the consistency of the bond or pattern is unmatched.”

What customers appreciate most is how much simpler and faster ultrasonic bonding is compared with sewing or adhesive methods, says Sara Karmilowicz, business development representative, Sonobond Ultrasonics. “Because there is no thread or adhesive involved, manufacturers immediately cut out the ongoing costs of consumables,” she explains. “The process itself is also very fast; ultrasonics can run several times faster than sewing and avoid the delays that come with glue application and drying.”

Seam quality is another key advantage, Karmilowicz points out. “Ultrasonic seams are completely sealed and uniform, with no needle holes and no risk of adhesive inconsistencies, which is essential for leak-resistant hygiene products,” she says. “And since there is no glue buildup or residue to manage, maintenance is lighter and downtime is reduced. All of these factors lead to higher productivity and lower operating costs over time.”

Thinner, Softer, Sustainable

As product demands rise, ultrasonic bonding is becoming a cornerstone of the next wave of hygiene innovation, according to Justin Lafferty, global product development manager, Dukane. Hygiene brands are pushing for thinner materials, better discretion, improved comfort and more sustainable designs, and ultrasonic technology is evolving rapidly to meet these expectations. 

Key advancements include the use of localized, precision energy that protects softness and breathability in ultra-thin materials, support for mono-material and recyclable constructions and the development of next-generation bond patterns, including curved seams and engineered stretch zones optimized for comfort and fit. Additionally, digitally accelerated development is enabling faster line setup and smoother global rollouts for hygiene manufacturers, he adds.

Similarly, Karmilowicz of Sonobond sees the hygiene market shifting toward lighter, softer and more breathable nonwoven materials. “Ultrasonic bonding fits that shift extremely well. Because it’s a precise, low-stress process, it bonds thin or delicate substrates without damaging them, which is important for today’s comfort-focused designs.”

Sustainability is also reshaping the landscape. By eliminating adhesives, ultrasonics naturally supports cleaner manufacturing and can help simplify recycling when the materials are compatible. “As new eco-oriented materials and multi-layer structures appear, we continue to refine our tooling and process controls so the manufacturers can confidently use them with our ultrasonic bonding equipment,” Karmilowicz adds.

From a sustainability standpoint, Eifler of Herrmann Ultraschall says manufacturers face increasing pressure from global regulations and corporate ESG goals to reduce their environmental footprint. Ultrasonic bonding supports these objectives by eliminating adhesives, which reduces chemical waste; cutting energy consumption by 60 to 70% compared to adhesive-based processes; and helping companies meet carbon reduction targets and comply with sustainability standards.

As nonwoven materials continue to advance, more opportunities within the absorbent industry become available, according to Gil of Chase Machine and Engineering. “Thinner, lightweight materials can often be bonded much faster, which helps drive down the cost of manufacturing as well as improve the breathability and flexibility of the end product,” he explains. “When using adhesives, factors such as breathability, delamination due to heat or fluid penetration, flexibility and softness (hand) must all be considered. When designing new products that can be manufactured with ultrasonic technology, these issues are of less concern. Ultrasonic bond patterns may be selected that provide not only adequate weld strength but the desired flexibility, breathability and appearance, as well as creating a superior product.”

Unser, of MS Ultrasonic, adds that ultrasonic technology offers compatibility with sustainable and mono-material concepts. Because ultrasonic welding works purely via frictional energy in thermoplastic materials, no foreign substances are added. “This is ideal when brand owners move toward glue-free, mono-material products and improved recyclability, since adhesives and other additives can negatively impact recycling streams,” he says.

The company’s new adhesive-free solutions for closure systems are an example of this. In April 2025, Gottlieb Binder and MS Ultrasonic introduced this new generation of in-line welding for the personal care industry. It enables a completely adhesive-free diaper closure system, delivering a very soft closure, lower production costs and simplified processing. 

Hook tapes are welded directly to the nonwoven or film chassis instead of being glued, creating a particularly soft and comfortable closure while eliminating adhesives and their associated costs and complexities. Additionally, the process is designed to be integrated directly into the primary hygiene line, not as a separate offline step. This opens up new process layouts, reduces handling steps and logistics and increases overall line efficiency.

Further, by removing glue, manufacturers reduce direct glue and adhesive tape costs, waste from expired or partially used adhesive components and cleaning and disposal needs for glue residues. At the same time, they gain a solution fully aligned with sustainable, recyclable product concepts. 

“This cooperation with Gottlieb Binder creates new application possibilities not just in baby care, but also across personal care, medical and technical nonwovens wherever hook-and-loop closures are used,” Unser says.

Other ultrasonic equipment suppliers are also advancing their technologies to better support end-product manufacturers.

Along with its standard line of ultrasonic sewing machines (FS-90 and FS-180), Chase Machine and Engineering has recently developed an Ultrasonic Sewing machine used to sew around the perimeter of a tube or sleeve. It has a cantilevered anvil and ultrasonic welder that provides the operator with the ability to weld contoured shapes. This type of manual ultrasonic sewing machine may be used to help make any type of contoured or hard-to-manipulate products, according to Gil.

Dukane’s range of ultrasonic technology is structured in performance tiers, allowing manufacturers to select solutions tailored to their specific process requirements—from mid-tier systems such as 30 kHz blade and 40 kHz rotary units used for elastic attachment, construction bonding and lamination, to top-tier offerings including 20 kHz blade, 30 kHz rotary, OptiBonder and RAM (Rigid Acoustical Mount) technologies designed for higher precision and more demanding materials. OptiBonder is tailored for intermittent bonding, while RAM (Rigid Acoustical Mount) delivers continuous-contact anvil bonding without the closed-loop complexity used in intermittent systems. Dukane’s ultra top-tier solutions, such as Quadro and 20 kHz rotary solutions, support the highest line speeds and the most demanding continuous bonding environments.

“Instead of locking manufacturers into a single bonding approach, we offer a full toolkit—from intermittent to continuous, from blade to rotary to Quadro—so they can match equipment to product design, speed requirements and long-term cost goals,” says Lafferty.

For Dukane, several initiatives are advancing quickly, including commercial deployment of adhesive-free elastic attachment, the introduction of curved leg elastic solutions for improved fit and reduced waste and expansion of the Kimberly Center of Excellence for pilot-scale development and validation. 

Opportunities Ahead

According to Sonobond, hygiene applications remain one of the strongest growth drivers. In these products, Karmilowicz says there is a real need for soft, reliable, leak-proof seams, and ultrasonic bonding delivers that consistently. Medical and protective apparel is another area of steady growth, especially as manufacturers focus on dependable barrier seams. Filtration is also expanding quickly, she adds, with ultrasonic bonding allowing filter media to be sealed without punctures or adhesive contamination. 

MS Ultrasonic is seeing similar patterns. Strong growth in hygiene is driven by baby diapers and pants—especially premium and ultra-thin concepts where soft, breathable and glue-free constructions are in demand—as well as adult incontinence and feminine care products, where discretion, comfort and reliability are crucial. Outside of hygiene, growth is occurring in medical and PPE (personal protective equipment) nonwovens, as well as technical nonwovens, including filtration, wipes and industrial fabrics, where continuous ultrasonic bonding and cutting improve productivity and edge quality.

“Across all of these segments, sustainability (less glue, less waste, lower energy) and comfort (soft, flexible seams and closures) are key trends that favor ultrasonic processes,” Unser says.

Dukane reports that growth is strongest in categories where fit, comfort, absorbency and discretion matter most, including adult protective underwear, adult briefs, premium baby diapers and training pants, and medical disposables and PPE. Beyond these core markets, the company is finding new opportunities through adhesive-free retrofits that boost uptime and eliminate glue-related maintenance, engineered bond patterns that enhance comfort, edge softness and brand identity, and innovative bonding architectures made possible by systems like Quadro, RAM and OptiBonder. 

“Our philosophy is to work closely with manufacturers, understand their unmet needs, and develop solutions that give them a competitive advantage,” Lafferty says. “When those solutions deliver measurable performance gains, OEMs naturally adopt and integrate them into new machine platforms.”

While hygiene remains a core market for Herrmann, the company is focusing on new ultrasonic applications in non-hygiene sectors where bonding challenges are similar, but solutions are less established, including filtration, medical and healthcare.

Ultrasonic bonding offers a clean, precise alternative to sewing, gluing or thermal processes in filter production. “This is especially relevant for automotive and industrial filters, where manufacturers seek stronger, particle-free seams and improved sustainability,” says Eifler. “The market currently relies heavily on adhesives and stitching, creating a significant opportunity for our ultrasonic bonding technology.”

In medical and healthcare, applications include lamination of multi-layer wound dressings, surgical drapes and protective covers. “Ultrasonic bonding ensures sterile, adhesive-free seams that maintain softness and skin compatibility, critical for patient comfort and regulatory compliance,” he says.