Numerical Analysis of Heat Transfer Characteristics in the Thermal-Transfer Printing Head under Pulse Heating Conditions

Thermal-transfer printing technology has gained widespread adoption in small-format printing devices owing to its fast printing speed, good image quality, and environmental sustainability. However, scaling this technology to large-format printing equipment remains challenging, primarily because the internal heat transfer mechanisms in the large-scale thermal-transfer printing head (TPH) are not yet fully understood. This knowledge gap limits further optimization of device design. A two-dimensional model was established to numerically investigate the internal heat transfer within the thermal-transfer printing head under pulse heating conditions. The simulations reveal that the internal temperature distribution adopts a star-like pattern, driven by the higher thermal conductivity of the bottom film, which accelerates temperature changes. The printing paper effectively filters the heat fluctuation from the heat generator due to its high specific heat capacity and low thermal conductivity. Parametric analysis demonstrates that the temperature of the heat generator reaches a maximum of 428°C at 70% of pulse width modulation and 500°C at an amplitude of 5.04 kW. These findings provide a theoretical foundation for optimizing large-scale thermal-transfer printing systems.