Thermal Transfer Printing Strategy for Mechanically Robust Wash‐Durable Electronic Textiles via Dual Cross‐Linking and Mechanical Interlocking

Thermal transfer printing (TTP) offers scalable patterning for electronic textiles, but poor mechanical compatibility and weak adhesion at the conductor–fabric interface often cause failure during deformation and washing. Here we report a TTP strategy that produces mechanically robust and wash‑durable textile electrodes using a dual‑crosslinked conductive composite (DCCC). The composite integrates PEDOT:PSS with sorbitol as a dopant/plasticizer, thermoplastic polyurethane (TPU) as a viscoelastic binder, and (3‐glycidoxypropyl) trimethoxysilane (GOPS) as a coupling crosslinker. GOPS covalently stabilizes the PEDOT:PSS network and chemically links it to TPU, while TPU chains interdiffuse with a hot‑melt adhesive (HMA) during transfer. Simultaneously, molten HMA penetrates textile pores to form mechanical interlocking, enabling strong bonding on diverse fabrics. The resulting electrodes exhibit high adhesion, with peel strength above 900 N/m and lap‐shear strength above 7.85 MPa. During machine washing, the sheet resistance initially decreases because of washing‐induced surface conditioning and then stabilizes, allowing the electrodes to retain electrical performance after 50 standard washing cycles. They also remain stable after 240 days of water immersion and 100 h at 85°C/85% RH, and tolerate repeated bending and abrasion. We demonstrate practical use in motion‑robust wearable ECG monitoring and low‐voltage Joule‑heating textiles for automatic thermal regulation. This work provides a general interface design for reliable, mass‑producible electronic textiles.