The thermal transfer film is usually made of polyethylene film as the bottom layer, the surface is printed with decorative layer, the surface is coated with protective layer, printing layer, release layer and adhesive layer, this multi-layer structure makes the thermal transfer film can be heated and pressurized by the thermal transfer machine, the exquisite and beautiful pattern texture of the surface of the thermal transfer film can be completely transferred to the substrate surface. After the transfer, the substrate surface presents a decorative effect of novel color and stable tone, so that the substrate surface has good performance such as heat resistance and light resistance.

The material of thermal transfer film includes substrate, protective layer, printing layer, release layer and adhesive layer. The substrate layer is usually made of PET (polyethylene terephthalate) material; Printing layer can use ink, resin and other materials; The protective layer is overlaid on top of the decorative layer to protect the pattern texture from damage while improving the wear and weather resistance of the thermal transfer film; In the process of thermal transfer, the release layer separates the decorative layer from the polyethylene film, ensuring that the pattern and text can be transferred to the substrate smoothly; The adhesive layer is located at the bottom of the thermal transfer film, and by heating and pressurizing, the decorative layer forms a chemical bond with the substrate surface to achieve the transfer of the pattern. Different combinations of materials can achieve different results, for example, high definition pattern transfer can be achieved with thermal inks, and better durability can be achieved with thermal resins.

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The surface of these thermal transfer films has a metallic luster, and the color is copper, gold, silver, blue and dark brown from left to right. Thermal transfer film is usually used to decorate metal products such as aluminum alloy picture frames, and the pattern and color on the film are transferred to the surface of the photo frame that needs to be transferred by heating, so as to achieve the decorative effect.