Driving the Future of Core Design in Disposable Hygiene Products

Keeping an eye on emerging trends for core materials is an important part of your job—and ours. The team at Bostik has our sights set on what’s being done in the disposable hygiene industry to support thinner core designs, increase softness, and create a more comfortable and natural fit. Take an inside look at what we see trending:

Topsheet

The use of thinner, nonwoven topsheets is helping to lower costs in some instances while enabling the development of products that have:

• Swirled fiber structures, softer polymers and silky spin finishes for softer, fluffy feel
• A thicker appearance as the result of manufacturing technologies but using less material 
• Better liquid acquisition while promoting dry skin and optimizing core utilization

Acquisition Distribution Layer (ADL)

Unlike thinner topsheets, ADLs are getting thicker in some core designs. A multi-layer construction, where each layer serves a different function, can help with:

• Quick acquisition
• Distribution across the whole core area
• Intermediate liquid storage before absorption into the core matrix 

Core Wraps

Core wraps—made with tissue or nonwoven materials—are being used more often. They help keep the fluff/SAP core matrix contained. The core wrap is especially needed to hold the SAP granules in place when manufacturers reduce fluff. As a result, the adhesive used with the core wrap also plays a key role in the overall core integrity and performance. 

Odour Control

Manufacturers are exploring a variety of options for core matrix materials to improve odour and bacteria control. This includes chemically modified fluff and SAP to help lower pH levels. At the same time, it neutralizes ammonia after urine makes contact with skin bacteria. Odour control and skin wellness are also improved because the environment does not support bacteria. 

The use of tea extracts and aloe vera, versus synthetic perfumes, are also emerging trends to mask odours.

Core Matrix

Core matrix trends include the use of synthetic nonwoven fibers instead of cellulose fluff. The fibers create an entanglement that prevents SAP clumping and helps keep the loose powder in place while also providing a cushion. This prevents product wearers from feeling the SAP powder when pressure is applied to the core. 

Fluff that is easily compressible is another emerging trend. This supports thinner cores and products that are more like underwear while having adequate absorption and good core integrity.

Core Adhesive

From thick to thin and every other material trend in between, the core adhesive is always the enabler that brings the system together. Components change. Trends come and go. Through it all, Bostik is at the forefront in understanding the makeup of the new materials so we can help you pursue trends that are the best fit for your products.

Two emerging core designs

In addition to these material updates to traditional core designs, two innovative designs have recently emerged:

• Compound core
• Channel core

In both cases, core adhesives play an important role in making them possible.

Compound Core

Primarily found in disposable hygiene products produced in China, compound cores do not use cellulose fluff. Instead, they are made by “sprinkling” SAP on a layer of high-loft nonwoven and enclosing this composite with a core wrap made of tissue or nonwoven. Compound cores are often constructed offline and transported to the hygiene production line. While poor wicking and SAP loss due to manipulation prior to final construction can be a problem with compound cores, the right core adhesive can help mitigate these concerns.

Channel Core

A channel core has longitudinal zones (channels) in the crotch area that are free of any absorbent materials. Instead, the upper and lower wrap are directly in contact and laminated with adhesive. Creating channels typically will help ensure:

• Better core integrity
• Better fluid and air circulation
• Less bulking and sagging
• Drier skin