Abstract: Using front panel of LCD television as a model system, the high-gloss surface part injection technology was studied using Taguchi method combined with finite element (FE) analysis and data processing. Wrapage, sink index, and volumetric shrinkage were selected as the main quality indexes. It was found that the pressure at v/p switch-over point was decisive for the wrapage, which decreased rapidly, quasi-linearly with increasing pressure at v/p switch-over point at the first stage, then increased slowly after reached a peak value. Injecting and packing pressure are two main factors for sink index and volumetric shrinkage, which decreased quasi-linearly with increasing injecting and packing pressure. When injecting pressure reached to a certain peak value, it became no longer importance to sink index and volumetric shrinkage.

Key words: high-gloss surface part injection technology, Taguchi method, numerical simulation, process characteristic, warpage, shrinkage, sink index