Patent ID: 6834532
Filing Date: 2004-12-28
Classification: G01N

Abstract:
A method of measuring a gas transmission rate of a plastic film, comprising:sealing a gas X into a test film bag which is formed by processing a test plastic film into a bag and has known mass and surface area; measuring a mass of the test film bag in which the gas is sealed, a plurality of numbers of times on the time series, while keeping a temperature constant in a temperature-controlled airtight vessel which is filled with a gas Y different from the gas X so as to make a pressure in the vessel equal to an internal pressure of the test film bag; and obtaining a transmission rate (a value representing the number of moles of a gas transmitted through a test piece with a unit area in a unit time at a unit partial pressure difference) associated with the gas X from a relationship between the measurement results, the mass of the test film bag alone, and the surface area.