Grease resistance test method for polymer coated soft packaging materials

摘要

Packaging materials for edible oils, butter, margarine and other foods containing fat have to satisfy very high requirements. Good grease resistance is one of the more important parameters in lengthening the shelf-life of the product [1,2]. Many different methods of grease resistance testing are known and applied for polymer films. Basically, they can be divided into two groups. In the first group various oils and other greases exist as a liquid medium [3,4], while in the second group there are different chemicals, e.g. turpentine or ra-alkanes [5-8]. The second group of testing methods, despite having a very short testing time, are limited by their poor correlation with trie real shelf-life of the package groups. Polymer film samples, flat or creased in two directions to form an X mark, are used for these methods. A new method for testing resistance to fat has been elaborated and tested in the Institute of Plastics Technology, Tampere University of Technology. Soft packing materials such as polymer films or paper coated with a polymer film may be tested by this method. The method allows an automatic registration of the time of failure with a camera. The results of investigation of several different packing materials are presented in this letter.