PURPOSE: To maintain freshness and marketability by airtightly providing an air-permeable lid on a protective plastic closed container having an opening and providing, on the air-permeable lid, a porous support layer such as a paper base, a first intermediate layer of a porous non-linear fiber material and an internal layer of a selectively permeable material.
CONSTITUTION: A package 10 comprises a relatively rigid protective plastic closed container 1, wherein a layer 60 in its lid 60 is a thin film of an adhesive air-permeable material serving as coupling agent or adhesive agent for a first intermediate layer 46 and a support layer 50, and the air-permeable material for a layer 48 is formed of aqueous solution of polysaccharide. The layers 46, 48 are laminated on the support layer 50 and formed by knifing of the layer 50 by aqueous solution or mixture of a porous material and a coupling material. As a result, the lid may be as thin as possible to minimize a drop in total permeability of the lid or may be thick enough to prevent the support layer 50 from being in contact with an internal layer 40.
CHIYAARUZU ERU MOTSUTO
RONARUDO JIEI UIIKUSU
