A product provided includes a packaging material, and the packaging material includes a multilayer structure. The multilayer structure includes at least one base (X), at least one layer (Y), and at least one layer (Z). The layer (Y) contains an aluminum atom. The layer (Z) contains a polymer (E) containing a monomer unit having a phosphorus atom. The multilayer structure includes at least one pair of the layer (Y) and the layer (Z) that are contiguously stacked. This product is excellent in gas barrier properties, and adapted to maintain the gas barrier properties at a high level even when subjected to physical stresses such as deformation and impact.