In the process of production, transportation and storage, plastic packaging bags often burst edges and are damaged, which seriously affects the product quality of enterprises. How can we solve the problem of burst edges and damage of plastic packaging bags? Next, xinhaoye packaging will interpret the methods to prevent plastic packaging bags from bursting and damage based on its own experience in producing high-quality plastic packaging bags.

1、 Common situations of burst edges and damage of plastic packaging bags

Edge burst and damage caused by automatic packaging: during automatic packaging, the filled contents have a strong impact on the bottom of the bag. If the bottom of the bag cannot withstand the impact, the bottom will crack and the side will crack.

Edge burst and damage during transportation and product stacking: the flexible packaging bag cannot withstand the internal pressure increase caused by commodity stacking pressure and friction during transportation, and the bag edge burst and damage.

Damage caused by the vacuum pumping process of the packaging bag: the thickness of the packaging bag is too thin, the packaging bag shrinks during vacuum pumping, and the contents have hard objects, needle corners, or hard objects (dirt) of the vacuum pumping machine pierce the packaging bag, resulting in edge explosion and damage.

When the high-temperature cooking bag is vacuumized or sterilized under high temperature and high pressure, the edge explosion and damage occur due to insufficient pressure resistance and high temperature resistance of the material.

Due to the low temperature, the frozen packaging bag becomes hard and brittle, and the poor freeze fragmentation resistance and puncture resistance cause the edge explosion and damage of the packaging bag.

2、 Reasons for edge explosion and damage of plastic packaging bags

1. Reasons for edge explosion and damage of packaging bags in the process of automatic packaging

Generally, the heat sealing strength refers to the bonding strength of two films bonded together by heat sealing and completely cooled. However, in the automatic packaging production line, the two-layer packaging material has not received sufficient cooling time, so the heat sealing strength of the packaging material is not suitable for use here.

There is a most suitable temperature point to achieve the best thermal viscosity of thin film materials, and when the heat sealing temperature exceeds this temperature point, the thermal viscosity will show a downward trend. In the automatic packaging production line, the heat sealing of the flexible packaging bag is almost synchronized with the filling of the contents. Therefore, when filling the contents, the heat sealing part of the bag is not completely cooled, and the impact it can withstand will be greatly reduced.

For the impact force of flexible packaging bags during content filling, the thermal viscosity tensile tester can be used to draw the thermal viscosity curve by adjusting the heat sealing temperature, heat sealing pressure and heat sealing time, and the best combination of heat sealing parameters can be selected for the production line.

2. Causes of edge explosion and damage during storage and transportation

Items packed in plastic bags will increase the gas pressure in the bag due to the stacking of items during storage and transportation, and then cause the edge explosion and damage of the flexible packaging bag. As the positions of edge explosion and damage are mostly concentrated in the heat sealing position between materials, that is, the weakest part of the heat sealing of flexible packaging bags, plastic packaging bags can be avoided by detecting the heat sealing strength of packaging heat sealing edges, and then changing materials or adjusting heat sealing process parameters.

The heat sealing strength of materials can be roughly divided into tensile heat sealing strength and expansion heat sealing strength according to the test method. What can be tested by the tensile machine is the tensile heat sealing strength, which is the ability of the packaging material to resist separation under the condition of consistent stress direction and uniform force value. It is especially suitable for evaluating the opening of the flexible packaging bag, but it is not suitable for solving the problem of breaking the flexible packaging bag, because the direction and size of the pressure in the bag causing the breaking of the bag are uncertain, and the materials near the heat sealing place may deform due to bearing part of the pressure, Pressure damage of flexible packaging bag.

The detection of expansion heat sealing strength requires the use of leakage and sealing strength tester, which needs to pressurize the soft packaging bag, and can detect the position with the worst and weakest strength in the whole package (not limited to the heat sealing position). Since the expansion heat seal strength cannot represent the average strength of the heat seal, there is no correlation between the expansion heat seal strength and the tensile heat seal strength. The expansion heat sealing strength is related to the size, geometric shape and material of the flexible packaging bag.

3. Reasons for edge explosion and damage of vacuum food packaging

Mainly for food vacuum packaging design and external vacuum packaging materials:

In terms of food vacuum packaging design, if the net content or volume of the contents exceeds the bearing range of the soft packaging materials used, the bags will be broken and cracked under a slight external force in the process of transportation or sales circulation. Generally, as the heat sealing layer of vacuum packaging bag, the material thickness shall not be less than 50um.

The above is the common edge burst, damage and causes of plastic packaging bags. The professional flexible packaging manufacturer xinhaoye packaging can select materials reasonably, has rich experience in heat sealing, and all bags will be fully inspected before leaving the factory, so that the packaging bags delivered to you will not only be beautifully printed, but also have quality assurance.