How to check the quality of wrapping film?

 

How to detect the quality of wrapping film?

Wrapping film is widely used in the packaging and transportation of various products. Wrapping film is also called stretch film. Toughness and shrinkage are the criteria for measuring the quality of stretch film. If the quality is not good, then you will not accept it after the packaging is completed. , Can not play the role of protection as it should be. So how to check the quality of stretch film?

1. A micrometer can be used to detect stretched film. It is not easy to grasp accurately by visual inspection. Because the diameter of a hair is about 7 filaments, the sensitivity of the hand feel is unattainable. Someone uses a scale to weigh the weight of each roll. In fact, the film is maintained. The thickness of the bottom paper and the glue are different, so it is difficult to accurately grasp. The thickness of the 9-thread mask is also coated with a layer of glue, so it should reach 11 threads instead of the total amount of stretch film plus glue 9 wire.

2. Peel the PVC plastic mask of the stretched film and the release test with silicone coating, knead the glue-coated side of the mask hardly to make the glue and the glue tightly bond together, and then pull it away, pay attention The longest glue filament between glue and glue cannot exceed 0.2 mm, so the possibility of degumming of the stretched film during use is extremely small.

3. The thickness of the PVC film is also very important, because it is related to the impact force received by the maintenance film, usually the thickness of the stretched stretch film is about 9 filaments. If deep carving is required, the thickness of the stretch film should be corresponding The increase of, otherwise it will be penetrated and damage the processed object.

Customers and friends should conduct a series of tests on the quality of the stretch film when buying stretch film. Stretch film is very important for packaging products, and its quality directly affects its role. Therefore, when selecting a stretch film, it is necessary to conduct quality inspections through professional methods.

What factors affect the stretch rate of stretch film?

Stretch film is a kind of transparent, flexible, high-strength, non-toxic and harmless polyethylene plastic film, which meets international environmental protection and health standards. Stretch film has the advantages of toughness, impact resistance, transparency and self-adhesiveness.

Influencing factors

1. The stretch film is rapidly cooled by a cooling roller, and then stretched longitudinally, and then stretched longitudinally to a greater degree, so that the polymer and the filled mineral particles can be separated to achieve the effect of opening the vent.

2. PP stretch rate can reach 8:1, stretch film generally does not use longitudinal stretch, stretch rate is limited by polymer through the use of copolymers or mixed with some metallocene PE, because the wide molecular weight distribution makes it resistant The tensile strength is relatively poor.

3. The structure of the polymer will change. Under such a limit stretching rate, the performance of the stretch film will be enhanced. Longitudinal stretching can open the pores that give the product breathability. These stretch films are filled with calcium carbonate and other minerals.