Characterization of In-Mold Coatings on RIM Encapsulated Modular Windows

In-mold coating (IMC) is used to provide protection against ultraviolet (UV) degradation of reaction injection molded (RIM) polyurethane encapsulated modular windows. IMC is a cost-effective method of producing weatherable RIM encapsulated windows. Coating thickness along with intrinsic UV absorbance plays an important role in providing the needed protection from UV degradation. The effectiveness of various thicknesses of in-mold coatings was measured using a spectrophotometer. The thickness of the in-mold coatings was measured using a scanning electron microscope (SEM). Experiments were conducted to determine the desired coating thickness for the IMC process. A statistical analysis was performed on the coating thickness of in-mold coated windows produced under experimental conditions in order to determine the process capability to provide the desired coating thickness. This data was used to establish a lower limit on mean thickness to enable statistical process control.