PURPOSE: To easily detect that the contents of a package are handled by forming a protection layer at the outer side of the container by using a coating material and forming a fragile coat on the protection layer by curing.

CONSTITUTION: An inner container 4 is contained in a package 2 and the package 2 is completely coated with an outside protection layer 6 which is formed of cyclic aliphatic epoxide for instance. The contents 5 are contained in the inner container 4. After the container gas been packaged, the layer 6 is cured by exposing the package in a band of ultraviolet rays for instance. Epoxide is excellent in the curing reaction and the viscosity characteristic and hence, easily formulated. Aryldiazonium salts and arylidonium salts can be used as appropriate optical initiator.