Acoustic-assisted printing of composite films with patterned hollow glass microspheres for thermal insulation

Highly efficient thermal management and thermal insulation are crucial in daily life, with thermal-insulation films used as key components to protect electronic devices from thermal damage. This paper presents an approach that uses an acoustic-assisted printing method to fabricate flexible composite films with orderly patterned hollow glass microspheres (HGMs) for highly efficient thermal-insulation applications. The acoustic-assisted printing method and system setup are first described. The printing parameters were studied, including the HGM concentration and excitation voltage. Two types of composite films with HGMs arranged in line stripe and cross patterns were printed. Then, experimental tests were conducted to study the thermal-insulation performances of these composite films. The results showed that the composite films with cross-patterned HGMs required 69.9 s to reach 48°C, representing a 44.2 s increase in heating time compared to films without such patterns. Subsequently, we attached the thermal-insulation film to the surface of a drinking glass and performed application tests by pouring hot water into the glass. Compared with the non-insulated condition, the cross-patterned film achieved a maximum average temperature difference of 4.37 C, demonstrating that the printed thermal-insulation films with patterned HGMs exhibited an excellent thermal insulation performance, highlighting the significant potential of these films for advanced thermal protection in daily applications.