To preserve initial freshness of a packaged object such as perishable food which cannot be sold as product if freshness is lost by applying preserving agent comprising mineral, enzyme, carbon or the like on one of faces of an intermediate material.

A housing is formed by laminating a surface material 3, an intermediate material 4 and an internal material 5, and an object to be packaged is received in the housing 1c. The surface material 3, the intermediate material 4 and the internal material 5 are adhered via adhesive or the like, wherein preserving agent 6 having function for preserving freshness, humidity, temperature or the like of the object 7 received in the housing 1c is applied on a face of the material 4 facing the internal material 5. The preserving agent 6 comprises mineral, enzyme, fine-powdered carbon or the like, wherein the mineral is manufactured by mixing rock mineral extracted from rocks and sea water mineral extracted from the sea water.