Plasma display panels (PDPs) with an MgCaO protective layer and a new manufacturing process were achieved, with discharge voltage decreased while productivity was maintained. The evaporation rate of MgCaO became lower with the increasing Ca content, decreased by 20% at Ca 8 wt%. However, by changing several settings of evaporation, the evaporation rate of the Ca 8 wt% was improved to be comparable to that of MgO. The PDP with the Ca 8 wt% MgCaO protective layer decreased the discharge voltage by 12 V compared to that with the MgO protective layer. The life characteristics of the PDP with the MgCaO protective layer were the same as those with the MgO protective layer.