At low temperature, the activity of molecular chains in the polymer materials of flexible packaging bags decreases, and the ability to resist external deformation decreases. Macroscopically, the ability to resist impact decreases, which leads to the decrease of flexibility and increase of brittleness of flexible packaging. When subjected to external impact, the problems of bag breakage and air leakage are very easy to occur.

So how to improve the flexibility of packaging bags at low temperature and reduce the breakage rate?

Firstly, packaging materials should be selected reasonably according to content characteristics and cost control. For example, OPP/LDPE material has good moisture-proof, cold-resistant, low-temperature heat-sealing tension and cost-effective. PA/LDPE material has good cold-resistant, impact-resistant and puncture-resistant properties, which is suitable for packaging products with harder contents, but its cost is higher. In addition, PE, PET/PE, BOPP/PE, BOPP/CPP and other materials can also be selected according to actual needs.

Secondly, the cold resistance of the package was monitored. Cold resistance is an important performance index of flexible plastic packaging materials. It is also an important index for evaluating the physical properties of flexible packaging materials under low temperature. It is also a key concern index for product packaging circulating in low temperature environment. Packaging bag manufacturers such as material cold resistance can not meet the requirements, in the case of low temperature, the material can not maintain the original physical properties, resulting in packaging bag cracking and cracking, unable to meet the protection of content. The cold resistance of packaging bags can be effectively improved by choosing suitable resin raw materials, improving the processing technology of packaging materials, adding appropriate plasticizers and choosing packaging materials with good low temperature resistance, so as to prevent the increase of damage rate of packaging bags under low temperature environment.

Customized packaging film with different batches of color difference will also have an impact on product quality. When there is color difference in different batches of the same product, it will cause a phenomenon of product quality instability to customers. Post-ink also affects the printing effect of packaging bags. If the ink is not used well, then our packaging bags will certainly be a problem, too much or too little ink will affect the clarity of the design and handwriting, and then the aesthetics will be much worse.

Packaging film is a kind of packaging bag which takes plastic as raw material and is used to produce various articles in daily life. It is widely used in daily life and industrial production. However, the convenience of this time brings long-term harm. The commonly used packaging film is made of polyethylene film, which is non-toxic, so it can be used for food filling. Another kind of film is made of polyvinyl chloride, which is also non-toxic. However, additives added according to the use of the film are often harmful substances to human body and have certain toxicity. Therefore, this kind of film and the packaging film made of this film are not suitable for food filling. In daily life, in fact, the common packaging film material is divided into six kinds.