复合三维刺绣结构电热织物及其可视化屏显OA

Driven by the dual demands of wearable hyperthermia and real-time information interaction,a one-step embroidery-only strategy that simultaneously achieves low-voltage Joule heating and pixel-level thermochromic display is proposed to overcome the uneven heating,poor breathability and easy delamination of conventional electrothermal films or coated fabrics. With 210 D silver-plated polyester conductive yarn as both top and bottom threads,subsequently replaced by 31 ℃ pink-to-white thermochromic yarn for the display top thread,5×5,6×6 and 7×7 arrays of three-dimensional spherical bulges were embroidered on a 40 mm×40 mm non-woven substrate via computerized embroidery.A 0.065 mm copper foil was adhered to the sample's back to establish a row-column addressing circuit,and electrothermal-chromic performance was evaluated under 3-7V DC using an infrared thermal imager.The 7×7 array exhibited a resistance of 44.7 Ω and reached a steady-state temperature of(59.6±0.5)℃ after 480 s at 7 V,with a power density of 687 W/m2.The 5×5 array,with a resistance of 33.2 Ω,achieved a peak temperature of(92.6±0.5)℃ at 7 V and a power density of 923 W/m2.The 6×6 array,with a resistance of 39.4 Ω,stabilized at(70.7±0.5)℃ with a power density of 778 W/m2.Throughout the test,temperature increased linearly with the square of the applied voltage,showing no hysteresis or drift.During 4 V heating/cooling cycles,all samples reached their maximum temperature within 60 s and cooled to 23 ℃ within 70 s.Stepwise heating from 3-7V showed monotonically increasing plateau temperatures at each voltage level,with clear thermal gradients among samples of different densities.The 7×7 sample underwent five on-off cycles at 4 V,5 Vand 6 V,with the first and fifth cycles overlapping perfectly.Bending the sample along either the transverse or longitudinal direction causes only negligible resistance fluctuation,remaining close to the initial value.Infrared thermal images revealed that heat initially concentrated at the three-dimensional spherical bulges and then spread uniformly across the substrate.For display samples with copper foil attached to the back,activating single points,multiple points,or entire rows/columns caused only the intersecting protrusions to heat.At 31 ℃,the pink front surface instantly turned white,enabling controllable color switching in a 7×7 pixel matrix. The three-dimensional embroidery structure integrates conductive paths and thermochromic pixels into one,delivering uniform,cyclic electrothermal output and a visual dot-matrix display at safe voltages ≤7 V.The process is fully compatible with existing computerized embroidery production lines,offering a low-cost,scalable route for smart thermotherapy garments,rehabilitation patches and wearable dynamic signage.