Abstract: Polymer-coated steel is a new type of metal packaging material under development, which has better performance in saving resources, energy, and environmental protection. It can replace packaging materials such as tinplate. In response to the research and development needs of domestic polymer-coated steel products, the research progress of the theory and technology of polymer-coated steel is analyzed and summarized. The trend of theory and technology development is studied from the laminating process, the combined mechanism of film and steel, the evaluation of laminating quality, the quality control of the film and the strip steel, the surface pretreatment and the surface modification of polymer film. It suggests that the temperature field of the contact zone between the film and steel is the key factor to determine the interface hydrogen bonding connection and even the film quality and film laminating speed. The temperature field stability of the film area and the controlling of interface cavity defect are studied. Intra-membrane recrystallization defects, reducing lateral and longitudinal film thickness fluctuations are the key to improving film quality and efficiency. We pointed out that the film quality should evaluated in different field such as bonding strength, film thickness uniformity, crystallization rate and plastic forming processing performance. The thermal behavior in the contact zone and the melting and solidification process of the polymer film should be studied. The flow, spreading, wetting and filling behaviors of the molten film under the action of roller on the rough surface of the substrate should be studied from the microscopic scale. The control theory and technology of the shape and thickness of the plate and the research methods be introduced, including the study of the dynamic characteristics of the coated roller system, and the lateral and longitudinal film thickness control methods and techniques are studied. In addition, several research proposals for improving film quality and efficiency are proposed, which may be helpful to the innovative research of current laminating theory and technology.

Key words: laminating quality, metal packaging, polymer-coated steel, thermal melting laminating