A startup originating from Gifu University, FiberCraze (Gifu City), has demonstrated that the moisturizing ingredient silk sericin, embedded within its newly developed nano‑porous fiber material “Craze‑tex,” is gradually released by perspiration and transfers to the skin. Daily News displays the article up to this point.
Conventional functional fabrics often rely on coating or microcapsules to apply active ingredients to the surface. However, these methods have been criticized for issues such as an initial burst release that lacks long‑term effectiveness, poor wash durability, and insufficient evidence showing whether the ingredients actually migrate to the skin. To address this, the company conducted verification tests using Craze‑tex. The material features a unique structure with countless pores ranging from the nano to submicron scale, allowing active ingredients to be stored inside the fibers while also offering excellent wash durability.
It was developed by leveraging the “crazing” phenomenon—an early‑stage fracture process in plastics in which fine cracks and microscopic voids form just before the material breaks. For the test, a 3‑cm square piece of the material containing sericin was used. After moistening it with artificial sweat and applying it to the skin for two minutes, the researchers observed the results and compared them with a non‑Craze‑tex fabric. The findings showed that Craze‑tex gradually released sericin, which remained on the skin.
According to the company, sericin transfers to the skin because its elements react with sweat, effectively pulling it out of the fabric. Even if all the sericin is released through sustained diffusion, the function can be restored by applying it again via spray or other methods. The company plans to commercialize the material for products such as supporters and innerwear. President Shunya Nagasokabe commented, “The original idea came from wanting to create something gentle on the skin for people with atopic dermatitis or eczema.
For those with severe symptoms, applying ointment and wrapping the area with plastic film or bandages is extremely burdensome, so we hope this can help ease that process.” Based on the results, the company also aims to promote Craze‑tex as a “functional ingredient platform.” While sericin was used in this case, incorporating different ingredients could provide additional functions and benefits. Nagasokabe added, “We hope to collaborate with various companies.”