A German design team has created a durable fitted cloth baby diaper made from a waterproof cover containing a sewn pocket and washable absorbent pads. The fully biodegradable and reusable diaper system, known as Sumo, is scheduled for launch in May.

“We have spent nearly three years developing the Sumo because we are so dedicated to the vision of achieving the highest, long-lasting performance with natural fibre,” co-founder Luisa Kahlfeldt says. “Every textile and component is custom developed from the fibre up.”

In 2019, Kahlfeldt, an award winning industrial designer, along with Caspar Böhme, an entrepreneur and creative director, created a design space in Berlin, Germany dedicated to making daily products that are more beautiful and safer for both users and the environment. Finding an alternative to disposable baby diapers fit well into these goals.

“We can’t keep polluting the planet with on average 5000 disposable diapers per child. The increasing pollution requires a rapid rethinking, the use of more sustainable materials and smart solutions for parents,” Böhme says. “There are not many hygiene products on the market that combine bio-based materials and reusability—and these often lack performance.”

The Sumo diaper system—and the Ufo removable superabsorbent inlay—rely on plant-based fibers which the founders say outperform polyester and cotton—the main material in most reusable diaper systems. The absorbent pad shows about a 40% reduction in rewet value and a reduction in acquisition time by about 45% compared to polyester and 40% compared to cotton. At the same time, the product is thinner, weighs less and is air permeable.

Sumo partnered with Kelheim Fibres, a German provider of viscose fibers, to develop the core. Kelheim’s Galaxy trilobal viscose fiber forms capillary channels to enable efficient liquid distribution in the acquisition distribution layer. In the absorbent core, Kelheim’s segmented hollow fiber Bramante stores liquid not only between but also within the fibers. Bramante can absorb up to 260% of its own weight. The core also contains polylactic acid (PLA).

The core was constructed using a combination of needlepunch and thermal bonded processes. The needlepunch gives both fibers types more space to absorb liquid and higher storage volumes. Thermal bonding offers bulkiness and increases strength, allowing the nonwoven to be fully washable. The founders say the product should last through potty training and could even be passed down to younger siblings.