Evaluation of acrylate penetration into printing blanket by IR imaging

In order to illuminate the penetration of UV curable ink vehicle into press blanket, IR imaging system was used as a new technique. Cross sections of blanket were prepared for IR imaging. Spectra data for imaging were collected by moving the sample stage automatically. Acrylate and UV curable ink into blanket could be characterized as a single wave-number map. In addition, each component in the UV curable ink could be characterized with a Principal Component Analysis (PCA). The penetration rate of low-viscosity acrylate was the same as that of UV curable ink with high viscosity. Moreover, the penetration rate of vehicle into the blanket was in order of acrylate monomer > acrylate oligomer > pre-polymer. This meant that the penetration of the acrylate monomer was affected that of UV curable ink into blanket. In addition, the photo initiator transferred together with acrylate monomer in the blanket.