Screening of coated metal packaging cans using EIS

A screening method for checking the suitability of a coated metal packaging can with a product is presented. Entire cans are tested, including deformations, beads, bottom, seams, curls, etc. It is designed to provide a pass/fail criterion in two weeks, even if the available amount of cans or product is low. It can therefore be used to decrease the time to market introduction, and to lower the amount of pack tests required.The method differs from other methods in that the data is qualitatively analysed and compared to the four most likely degradation types. If it falls in one of these categories an assessment of the mechanism can be given and a model is present to extrapolate the data to longer time periods. Examples are given where the proper analysis of the data lead to a correct assessment, whereas an oversimplified analysis (based only on the low frequency data) would yield an erroneous result.