一模四腔分区加热IMD膜高压成型研究

Study on IMD Film by High Pressure Forming of One-Mold with Four-Cavities Partition Heating

针对模内装饰(IMD)膜片一模四腔高压成型中膜片表面温度分布均匀性的问题,提出IMD膜片分区加热高压成型工艺。通过IMD膜片的热多向拉伸试验获取聚对苯二甲酸乙二醇酯(PET)膜片材料在不同温度下的黏弹塑性模型的材料参数,在ABAQUS软件中进行一模四腔PET膜片的分区加热高压成型有限元模拟分析,在此基础上,在高压成型机上进行了工艺实验。结果表明,在一定温度组合下的分区加热方式可以改善PET膜片局部区域厚度减薄率过高、成型膜片侧壁区域厚度极薄的现象发生,可防止膜片油墨被拉开、图案失真等问题。

Aiming at the problem of uniform temperature distribution on the surface of in-mold decoration （IMD） films by one-mold four-chamber partition heating high-pressure forming, the partition heating high pressure molding process of IMD film was proposed. The material parameters of the viscoelastic-plastic model of the PET film material at different temperatures were obtained by thermal muhiaxial tensile test of the IMD film. The ABAQUS software was used to perform the partition heating and high pressure forming of a four- chamber PET film by finite element simulation. On this basis, a process experiment was conducted on a high- pressure molding machine. The results show that the partition heating method at a certain temperature combination can improve the high thickness thinning rate of the local area of PET film and the thin thickness of the molded film side wall area, and also can prevent the diaphragm ink from being pulled open and avoid pattern distortion.