To provide a dielectric for a transparent plasma display panel without bubbles which is a composition without PbO, has low dielectric constant and thickness of 10 [mu]m or more even at a burning temperature of 200[deg.]C or less, and to provide a composition for a partition.The dielectric for the PDP containing a compound 1 expressed by the formula (1) or at least one or more kinds of compounds belonging to polyhedral origosilsesquioxane (compound 2) with R 6 SiO1.5as a repeating unit, or containing an inorganic-organic composite material using these compounds as a monomer, and the composition for the partition are provided. (Inorganic-organic composite material is a material consisting of expanded matrix containing silicon and an oxygen atom or a nitrogen atom, and at least one fraction of silicon is directly coupled to a substituted or non-substituted hydrocarbon atom).