In the process of producing ziplock bags, some processes will affect the shrinkage rate of ziplock bags. Special attention should be paid to the processing and production to avoid the unqualified ziplock bags. Here are some common effects on the shrinkage of ziplock bags the elements of.
1. The influence of the self-sealing bag's own structure:
In the same ziplock bag, the shrinkage rate of the part with smaller wall thickness is smaller than that of the wall thickness, the shrinkage rate of the part away from the insert is greater than the shrinkage rate of the part near the insert, the shrinkage rate perpendicular to the flow direction and the flow direction There is also a difference. In general, the shrinkage in the flow direction is greater than the shrinkage in the direction perpendicular to the flow. The shrinkage in the blocked direction of the ziplock bag is smaller than that in the unobstructed direction.
2. The effect of raw materials on the shrinkage of ziplock bags:
The shrinkage rate of ziplock bags produced with different raw materials is also different, but the shrinkage rate of different batches of ziplock bags produced with the same material is also different. This is mainly affected by the processing and production process. The shrinkage rate of crystalline plastics It is larger than amorphous plastics, plastics with poor fluidity have large molding shrinkage, and plastics with good fluidity have low molding shrinkage. If fillers are added to plastics, the shrinkage of molded plastics will be significantly reduced. Plastics without fillers will be produced. The shrinkage after molding is better.
3. The influence of pressure and temperature on the shrinkage of ziplock bags:
If the pressure is too high, the sealing of the ziplock bag will increase and the shrinkage rate will decrease. If the temperature of the raw materials used to produce the ziplock bag is increased, the volume of the ziplock bag will expand. However, the increase in the temperature of the raw material will make the viscosity lower, and the lower the viscosity will increase the pressure in the cavity, which reduces the shrinkage of the self-sealing bag. Therefore, the factors that ultimately affect the shrinkage of the self-sealing bag depend on the pressure and the temperature of the raw material. The comprehensive impact of the author.
1. The influence of the self-sealing bag's own structure:
In the same ziplock bag, the shrinkage rate of the part with smaller wall thickness is smaller than that of the wall thickness, the shrinkage rate of the part away from the insert is greater than the shrinkage rate of the part near the insert, the shrinkage rate perpendicular to the flow direction and the flow direction There is also a difference. In general, the shrinkage in the flow direction is greater than the shrinkage in the direction perpendicular to the flow. The shrinkage in the blocked direction of the ziplock bag is smaller than that in the unobstructed direction.
2. The effect of raw materials on the shrinkage of ziplock bags:
The shrinkage rate of ziplock bags produced with different raw materials is also different, but the shrinkage rate of different batches of ziplock bags produced with the same material is also different. This is mainly affected by the processing and production process. The shrinkage rate of crystalline plastics It is larger than amorphous plastics, plastics with poor fluidity have large molding shrinkage, and plastics with good fluidity have low molding shrinkage. If fillers are added to plastics, the shrinkage of molded plastics will be significantly reduced. Plastics without fillers will be produced. The shrinkage after molding is better.
3. The influence of pressure and temperature on the shrinkage of ziplock bags:
If the pressure is too high, the sealing of the ziplock bag will increase and the shrinkage rate will decrease. If the temperature of the raw materials used to produce the ziplock bag is increased, the volume of the ziplock bag will expand. However, the increase in the temperature of the raw material will make the viscosity lower, and the lower the viscosity will increase the pressure in the cavity, which reduces the shrinkage of the self-sealing bag. Therefore, the factors that ultimately affect the shrinkage of the self-sealing bag depend on the pressure and the temperature of the raw material. The comprehensive impact of the author.