At present, in people’s minds, the intuitive evaluation of commodities mainly depends on its appearance packaging. Therefore, choosing a good packaging material can not only reflect the enterprise image, but also is an important way to show the quality of products.
The performance of different plastic packaging film is different. So when we choose film, we need to consider some basic functions, mainly protection function, promotion function, the adaptability of packaging machinery and other special requirements of applications.
There are 12 reference standards we should know when we source plastic flexible packaging products.
As a packaging material, the protection of plastic film for commodities is the most important and basic function. If the plastic film does not have a reliable protective effect on the packaged product, resulting in damage or devaluation of the product, it loses its value as a packaging material. The protection function of plastic film on commodities is multifaceted. Different commodities and different packaging forms have different emphases on the protection function of plastic packaging film.
To prevent commodities leakage or external substances into package to destruct and pollute commodities. It directly reflects the mechanical performance, such as tensile strength, tear strength, falling impact strength (drop impact) and anti-puncture strength, etc.
Good Welding Strength
Welding strength is also a necessary condition for plastic film bags to protect goods reliably. If welding strength is not enough, welding will become the fatal weakness of the plastic film bag. Because of the split of welding seam, plastic bag will lose the protection function to the commodity.
Barrier refers to plastic film performance of preventing oxygen, carbon dioxide, nitrogen and other gases, like aroma, water vapor etc through. When the range is not clear, it generally refers to the barrier for oxygen, carbon dioxide, nitrogen and other non-polar gas.
Light transmittance and Haze
Light transmittance and haze are important indicators to determine the visibility and clarity of packaged goods, and have a great relationship with the display effect of goods. They are indicated by percentages (%). Higher light transmittance means better transparency of plastic film. And higher haze indicates worse clarity.
The glossiness is the reflection ability of the plastic film when it is illuminated. It is expressed as percentage relative to the reflected brightness of the standard surface.
Good Smoothness helps plastic film move smoothly on packaging line and avoids the damage due to high resistance during movement. The smoothness of the film can be described by the friction coefficient. Smaller friction coefficient means better smoothness.
High and low-temperature resistant properties are often considered. Such as refrigeration, especially for frozen food, plastic packaging needs to have good resistance performance to low temperature. For cooking food, plastic packaging needs to have a good high-temperature performance, and so on
When packaging food or medicine, the selected plastic packaging film must have good hygienic performance, in line with national health standards requirements to ensure that the plastic film will not cause commo10dity pollution.
Good air tightness can effectively block the exchange of gas inside and outside the packaging and it is necessary for most products.
Good moisture resistance is an effective means to protect goods. The moisture resistance of norma plastic film becomes better with the increase of thickness and becomes worse with lower temperature.
For oily foods, such as sausages, bacon, etc., the plastic packaging must be resistant to oil; otherwise it will affect the quality of products. Different industries have their own emphases to consider. When we source plastic packaging
products, in the premise of meeting standards, we should try to choose relatively low price packaging to save costs and improve the competitiveness