Patent ID: 6658919
Filing Date: 2003-12-09
Classification: G01N

Abstract:
A method of measuring the permeability of a coating on a plastic wall (1) to low-molecular gases, for example oxygen, wherein the diffusion coefficient and/or solubility coefficient of the coating with respect to the low-molecular gas is approximately an order of magnitude lower than that of the plastic wall (1), in which the space (4) only on the coating side is subjected to the action of a first fluid (5) and is flushed through until substantially only said first fluid (5) is in said space (4), characterised in thatthe first fluid is a test medium (5) with at least one component which can diffuse into the plastic wall (1) and be absorbed there, after the step of subjecting the coated space (4) to the action of the fluid test medium deposited on the coated surface is removed therefrom, thereafter the coated space (4) is subjected to the action of an extraction medium (7) in which the test medium (5) is well soluble and the test medium (5) can be measured, and the concentration of the test medium (5) in the extraction medium (7) is measured.