The process of heat transfer printing is to transfer the decorative patterns on the surface of the decorative materials  applied in the surface of the decorative building materials by heating the heat transfer film once.In the process of heat transfer printing, the protective layer and pattern layer are separated from the polyester substrate by the combined action of heat and pressure, and the whole decorative layer is permanently glued to the substrate by hot melt adhesive.The heat transfer film is made of polyethylene film, and the decorative layer of wood grain is printed on the paper.The surface is coated with a protective layer, a bottom color layer, a stripping layer and a hot-melt adhesive layer. By heating the high-temperature silicon roller and applying temperature and pressure on the transfer foil, the transfer layer composed of decorative wood grain printing layer, surface protective layer and bottom color layer is separated from polyethylene and transferred to the surface of wood-based panel or furniture parts, thus forming decorative surface graphics, which have excellent performance of wear resistance, heat resistance and light resistance, novel and beautiful patterns and stable tone, It is a kind of widely used decorative material.