PROCESS FOR DETERMINING OXIDATION-DEPENDENT CHARACTERISTICS OF SIMILAR PLASTIC ARTICLES, AS WELL AS USES OF THE PROCESS AND APPARATUS FOR PERFORMING THE PROCESS ON LARGE INJECTION MOULDED PRODUCTS, PARTICULARLY BOTTLE CRATES

摘要

ABSTRACTThe invention relates to a process formeasuring the characteristics of test articles made fromplastics particularly polyethylene or polypropylene, toestablish whether they are made from non-regenerated,regenerated or optionally a similar plastic which hasbeen regenerated to a certain extent by the infrared spectro-metric measurement of the transmission - absorption in thecarbonyl group band range of the plastic. According tothe invention, the transmission - absorption is measuredin the carbonyl group band range at at least two differentthicknesses of the same plastic and the thickness dependenceof these measurements is used as a measurement criterion.The invention is more particularly used on bottle cratesor other large injection moulded articles and can be usedfor classification preferably with sorting according toageing criteria, also in the case of test articles madefrom regenerated material, as well as for the selectionof old crates suitable for producing regenerated material.The invention also relates to infrared spectrometric meanssuitable for performing this process.