Thermal paper consists of a substrate and a coating containing a thermal dye. The substrate is usually made of cellulose, while the thermosensitive layer is composed of pearlite star shaped particles or nanoscale particles. The basic principle of this substance is that after local heating, the microscopic particles in the coating will approach the critical temperature, leading to chemical reactions and the formation of colors or images. In a sense, the printing process of thermal paper records information through "burning".

Thermal paper has multiple advantages compared to traditional inkjet or laser printers. Firstly, it uses thermal energy as an activator instead of ink or powder, which makes the cost lower and more energy-efficient. Secondly, due to the absence of ink or powder spray, the printing process is cleaner, reducing environmental pollution and avoiding the problem of printer head clogging. In addition, thermal paper has faster printing speed and a compact and lightweight printer, making it suitable for mobile printing and portable devices.

However, thermal paper still has some drawbacks. Due to its use of chemical reactions to record information, its printing quality is affected by many factors, such as temperature, humidity, and other environmental factors. It is susceptible to UV radiation and oxidation, which can affect storage time and long-term preservation. In addition, the images generated by thermal paper may fade or distort, making it unsuitable for scenarios that require high fidelity images, such as photography and art printing. Finally, due to the limited applicability of thermal paper, it is usually used to print specific types of labels, receipts, invoices, and other temporarily saved files, and is not suitable for printing long-term saved or high fidelity documents.

Overall, thermal paper is a low-cost, energy-saving, and clean printing method, but it also has its scope of application and drawbacks. When choosing a printing method, it is necessary to consider comprehensively based on actual needs.