NUMERICAL PREDICTION OF PRODUCT DEFORMATION AND IDENTIFICATION OF MAJOR CONTROLLING FACTORS DURING THE IML PROCESS INCLUDING THERMAL IMPACT

Abstract

The in-mold labeling (IML) process has become a popular choice for the exterior decoration of many mobile devices due to its capability of rich color representation with a relatively easy manufacturing procedure. A molten polymer is injected into a cavity where pre-decorated film has been initially inserted. A heterogeneous characteristic of involved material coupled with various processing parameters can induce defects of the final product such as film delamination, wash-out, and flow-mark. In this study, major controlling parameters for the deformation of the final product have been identified with the design of experiment (DOE) method using several nondimensional quantities of temperature, material property, and thickness ratio. MOLDFLOW and ABAQUS software has been simultaneously used to simulate the injection process and thermal impact process, respectively. We found that the thickness ratio is a critical factor on final deformation, and the material property ratio has a relatively minor effect.