US 2002/0116985 A1 · Process and apparatus for testing multi-layer composites and containers produced therefrom

Abstract

The invention relates to a process and an apparatus for detecting gas-permeable damaged points in an electrically non-conductive layer which can exist as a single layer or as a multi-layer composite with at least one conductive layer. A test subject is disposed in a test chamber. On the one side of the layer which is to be examined is an electrically-conductive layer, and on its other side is a gas environment. The gas in the gas environment is ionized at a given pressure by means of an electrical discharge. A counter-electrode disposed in the test chamber forms a test current circuit, together with a voltage source and a measuring device. If the layer which is to be tested contains a damaged point, a distinct current is measured in the test current circuit, if the gas discharge is maintained, which serves as an indicator for a damaged point. The process allows the detection of damaged points which are fluid-tight, or which are only present in a non-conductive layer in the case of a multi-layer composite. The process is used in the case of containers for sensitive pharmacological preparations if rigid requirements are placed on these containers with regard to their integrity during storage times or periods of use which extend over a plurality of months.

Claims27

Dependent claims

A process for detecting gas-permeable damaged points in test subjects which comprise an electrically non-conductive layer, wherein an electrically-conductive layer lies opposite the electrically non-conductive layer on the one side and a gas environment lies opposite the electrically non-conductive layer on the other side, wherein

The disposal of at least one test subject in a test chamber which has been evacuated to, and maintained at, a given pressure, and
Ionisation of the gas by means of an electrical gas discharge in the gas environment on the other side of the electrically non-conductive layer, and
Application of an electric voltage between the electrically-conductive layer which lies on one side of the electrically non-conductive layer and a counter-electrode which is disposed in the test chamber, wherein the electrical voltage generates an electrical field strength in the area of the electrically non-conductive layer which lies below the dielectric strength of the electrically non-conductive layer without gas-permeable damaged points, and
Measurement of a current flowing though the ionized gas between the electrically-conductive layer and the counter-electrode disposed in the test chamber—in the case of a gas-permeable damaged point being present in the electrically non-conductive layer—which acts as an indicator for the gas-permeable damaged point in the electrically non-conductive layer, with the electrical gas discharge being maintained.

1 more element

An apparatus for testing test subjects made from an electrically non-conductive layer for gas-permeable damaged points, wherein

an electrically-conductive layer which is disposed on the one side of the electrically non-conductive layer, and
a gas environment which is disposed on the other side of the electrically non-conductive layer, and
means for evacuating the gas environment, and
an electrode which is provided in the gas environment, and
a counter-electrode which is provided in the gas environment, and
a test current circuit in which the counter-electrode is disposed.

3 more elements

Dependencies are inferred from the claim text.

Process and apparatus for testing multi-layer composites and containers produced therefrom

Life of this patent

Process and apparatus for testing multi-layer composites and containers produced therefrom

Life of this patent

Abstract

Claims27