Due to cost and property of flexible package, thickness should be seriously confirmed. Generally, heatsealing layer should follow market standard,support strength layer should follow product package weight, function layer depends on shelf life request.
Here are the test methods to confirm lamination structurer thickness:
1.According to the maximum allowable water absorption of the packaged product or the maximum allowable dehydration of the product, this method mainly adapts to the moisture-proof packaging design of the product
2. According to the maximum allowable oxygen absorption of the packaged product, this method is mainly suitable for the barrier packaging of the product which is very sensitive to oxygen, and the key is to calculate the oxygen permeability coefficient of the soft packaging composite material.
3. According to the maximum number of microorganisms per unit volume or per unit surface area, the method is mainly suitable for anti-mildew packaging of products which are very sensitive to microorganisms, the key is to determine the types of product microorganisms and the rules of their propagation and growth
4. Based on the maximum amount of carbon dioxide or oxygen permeation allowed by the packaging container, the method is mainly applied to the inflatable insurance packaging of the product. Products with declarative activity both require oxygen insurance or maintain bright color, high concentration of carbon dioxide is needed to inhibit the growth and reproduction of microorganisms. The key is to calculate the permeability coefficient of oxygen and carbon dioxide.
The key is to calculate the permeability coefficient of oxygen and carbon dioxide. Product packaging, sometimes not only to achieve moisture-proof packaging purposes, but also to achieve oxygen-resistant packaging or mildew-proof packaging purposes. Therefore, the thickness of composite packaging material is usually determined by one of the main packaging purposes and the shelf life of the product, and then the theoretical shelf life of the designed packaging is estimated according to the thickness of the material and another packaging purpose, to verify the rationality of the design of packaging.