1. Heat transfer printing head

The Heat transfer printing head is mainly composed of a surface film protective layer, a bottom film protective layer and a heating element. The heating element is a conductive silk screen. With the help of the heat generated by the voltage pulse, the coarse particles of the ink layer in the graphic part are raised and melted to complete the ink transfer by thermal diffusion.

The printing speed of heat transfer depends on the time required for each line of graphics. Therefore, the transfer head and the transfer paper should have good heat transfer properties, so that the heat generated by the heating element can quickly pass through the protective layer, the transfer paper substrate and the gap and finally transfer to the surface of the substrate to ensure that the ink has sufficient transfer time.

2. Ink

The composition of heat transfer ink is generally three parts: pigment (pigment or dye), wax and oil. Among them, wax is the main component of heat transfer ink.

During printing, the viscosity of different inks has a direct relationship with the heating temperature, and the heating temperature and the viscosity of the ink should be strictly controlled. Practice has proved that when the heating temperature is 60-100 ℃, when the ink is melted, the viscosity value of the ink is stable at about 0.6pa·s, which is the most ideal. Generally speaking, the closer the ink is to this state, the better the transfer performance.

3. Transfer medium

Chemical properties: Making the ink adhere well and evenly is two important performances of the chemical properties of the transfer paper substrate. The chemical properties of transfer paper in production directly affect the quality of printing.

Good thermal performance: Since the transfer process is achieved by means of high temperature, the material of the transfer paper must be able to withstand the influence of the transfer temperature and keep the properties unchanged.

4. Substrates

Experience has shown that substrates with a slightly rough surface produce better quality prints, which is a characteristic of heat transfer printing. Because the rough surface of the substrate indicates that the substrate has a large surface energy, the ink on the transfer paper can be transferred to the substrate well, and the ideal level and tone can be obtained, but too rough will affect the normal operation of the ink. Transfer is not conducive to the realization of the printing process.