Characteristics Research And Optimization Design About Coating System Of Solventless Laminator

At present, the laminating process of flexible plastic packaging mainly uses the solvent adhesive for laminating. But the problems of solvent residues and emissions have brought some hidden perils for food packaging safety and environmental protection, which are restricting the development of flexible plastic packaging industries. The solventless laminating process uses the solventless adhesive whose solid content is 100% for laminating production, no solvent emission and environmental protection, health, safety, and high efficient, which has attached great importance of the industry experts and scholars.The precise control of coating weight is the direct factor in the solventless laminating process, which can make production achieve the best. Because the solventless coating weight is little and affected by a number of factors, it is difficult to control the coating weight accurately, which causes some quality problems and is the key problem that restricts the development of solventless laminating technology. Therefore, dedicating to the research about characteristics of solventless laminator coating system and transfer law of coating weight is very important. Through comparing with the traditional solvent dry laminating process, the characteristics and the advantages of solventless laminating process were introduced systematically. The coating system is the core part of whole equipment. The structure principle and transfer characteristics about coating system were explained. The speed ratio between transfer steel roller and coating steel roller, as well as the clearance between metering roller and transfer steel roller, is the decisive factor which affects the coating weight, while the host speed and adhesive viscosity also cause some certain error influence to coating weight. In view of each effect factor about coating weight, laminating experiments were made based on the orthogonal experiment table, which was designed through scientific orthogonal design method. The changing laws on the coating weight with the speed ratio between transfer steel roller and coating steel roller, the clearance between metering roller and transfer steel roller, the host speed or adhesive viscosity were analyzed through the intuitive analysis and the effect curve analysis of orthogonal table. According to these changing laws, the test data of coating weight were fitted and optimized by using the mathematical analysis software of MATLAB and least-square method, the mathematical models about coating weight with these affecting factors were created and the best production plans were pointed out. The user interface (GUI) design platform was developed to improve the man-machine communication and master the coating weight accurately. Finally some improvement suggestions were put forward to improve the coating quality. This paper provides the basis for identifying the quality of laminating products and mastering the coating weight accurately.