| The paper summarized the development of finish foil used for surface determination of wood-based panel and waterborne coatings, analyzed the water-based technology and development trend of melamine-acrylic coatings. Solvent-based coatings used organic solvent as the dispersion medium, which not only pollute the environment, but also waste resources and energy. Water-based coatings used water as the dispersion medium, which can greatly reduce the VOC content and save cost. Finish foil is a kind of paper-based decorative coiled materials, and its surface coating should be cured quickly in a short time in order to meet process technology, and the cured film must be continuous and smooth, especially owns excellent physical and chemical properties. In view of these questions, we have a mass of experimental study so as to prepare water-based coatings used for finish foil, which includes the raw material selection, formulation design, manufacturing process and curing performance of the coatings. The main body content divides into the following parts:(1) Designed formulation. We studied the effects of all components on performance properties of coatings and analyzed the mechanism of each component before preparing the waterborne coatings. Choose the best coating type used for finish foil and various materials according to the functioning mechanisms, and designed the optimized formulation. Furthermore, taking into account environmental protection requirements, the selected components should not harm the environment and release VOC as little as possible.(2) Studied the effects of all components on performance properties of water-based coatings. First, we researched the types of film-forming resins and the results showed that when melamine resin etherified slightly with methanol and styrene-acrylic emulsion containing the appropriate contents of hydroxyl group were used as film-forming resins, the coating could be cured fast at prescriptive temperature and has favorable cure performance. Secondly, the effects of melamine/acrylic mass ratio in coatings formulation and baking temperature on performance properties of coatings were studied. Last, some various additives should be added to water-based coating so that the coating and the cured film possess some special performance and achieve functional requirements. Taking into account the impacts between the components, we carried out contrast experiments through selecting a series of additives for each additive, and determined the best additive combination and adequate amount that could make film possess superexcellent properties. Through the above experiment analysis, the best formulation of water-based coatings used for finish foil was determined. According to the national standard requirements and targets, the coating performance and properties of cured film which include dry heat resistance,wet heat resistance,pencil hardness and stain resistance were tested, and it was observed that all these properties meet the standards, especially, release of toxic substances was far below the scope of national standards.(3) Studies on cure reaction of waterborne coatings used for finish foil. In this part, cure characteristics of cured and uncured coatings water-borne melamine-acrylic coatings was studied. Through analyzing the FTIR spectra of samples, we researched semi-quantitatively the content changes of different groups before and after cure reaction, analyzed the cure mechanism of the coating and the reasons for fast curing. The range of temperature that curing reaction of the coating occurred in was studied by DSC, and further validated that water-based melamine-acrylic coatings used for finish foil could be cured fast in the range of temperature set by this study.In summary, this research has the reference value to further theoretic development and practical application of surface decorating materials used for wood-based panel and waterborne coatings.
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