PACKAGING MATERIAL FOR RETAINING FRESHNESS OF VEGETABLE/ FRUIT

摘要

PROBLEM TO BE SOLVED: To obtain a packaging material in the form of multilayer film with the innermost layer consisting of a specific thermofusible resin layer and provided with fine (un)penetrated holes so as to control oxygen permeability, thus capable of retaining the freshness of vegetables/fruits packaged therein over a long period. ;SOLUTION: This packaging material is obtained by forming numerous fine penetrated holes 4 or unpenetrated holes 5 each having a diameter of several to several tenth μm on a multilayer film 1 with at least the innermost layer consisting of an antifogging thermofusible resin layer 3 such as low-density polyethylene so as to control the oxygen permeability of the multilayer film 1. Formation of the fine holes 4, 5 on the multilayer film 1 is conducted in such a way that the oxygen permeability of the film 1 just after forming the holes 4, 5 fall within the range of 5-10 times that, i.e., 3,000-30,000cc/m².day.atm needed for retaining the freshness of the vegetables/fruits to be packaged (pref. 15,000-300,000cc/m².day.atm).;COPYRIGHT: (C)1997,JPO