ASO Co., Ltd.

 In some cases, customers are told that the inner surface of plastic bags is ‘almost free of micro-organisms because the resin is melted at a high temperature (180 °C) in the inflation process’.
  This is completely unfounded.

 

 This is because polyethylene tubes are heated to approximately 180 °C, but the molten resin is blown up by air in the inflation process.
Therefore, the initial bubble in which the tube is formed is filled with atmospheric air in the factory, while the air for adjusting the bubble is supplied by a compressor.
  The temperature in the bubble is not high enough to kill micro-organisms. In short, the uncontrolled air is no different from that of products in the general environment.

 Air used for normal inflation rarely has a sterilizable filter, which allows relatively large particles (5 µm, 10 µm) to enter the air.
  It is therefore essential for pharmaceutical packaging that the inflation air must be filtered by a filter of at least 0.3 µm or smaller.

 The surface of the bag is also contaminated by contact with various rolls such as nip rolls and tension rolls in several processes, including inflation, bag-making, and printing. These rolls are also significantly contaminated depending on the working atmosphere and cleaning standards of each process.

Especially in the following situations, the risk of microbial or foreign matter contamination increases:

 To manufacture polyethylene bags suitable for pharmaceutical packaging, the following management is important:

 By implementing these measures, the quality and safety of polyethylene bags for pharmaceutical packaging can be ensured.