Soft mechanical treatments of recycled fibers using a high-shear homogenizer for tissue and hygiene products

This study introduces an innovative approach for developing high strength-high softness recycled fibers through soft mechanical treatment. Recycled fibers from old corrugated containers were treated using a homogenizer, a refiner, and in tandem. The recycled fibers and tissue paper sheets after the treatments were evaluated for the effect on critical properties such as fiber morphologies, freeness, water retention, hard-to-remove water, bulk, softness, tensile strength, and water absorption. High softness and tensile strength were achieved with mechanical treatment by utilizing a homogenizer alone or in tandem with a refiner. Overall, the homogenized recycled fibers and tissue paper sheets provided higher bulk, water absorption, and tensile strength while maintaining the softness and drainage (freeness) behavior similar to unrefined paper sheets. It was found that homogenization helps in deflocculating the recycled fibers without negatively affecting the fiber quality, such as fines generation.

Automated summary

This study introduces an innovative approach for developing high strength-high softness recycled fibers through soft mechanical treatment, achieving high softness and tensile strength by utilizing a homogenizer alone or in tandem with a refiner. The homogenized recycled fibers and tissue paper sheets provided higher bulk, water absorption, and tensile strength while maintaining the softness and drainage behavior similar to unrefined paper sheets. Homogenization helps in deflocculating the recycled fibers without negatively affecting the fiber quality, such as fines generation.