How to observe the heat sealing test of flexible packaging films?

In the field of flexible packaging, the heat sealing process of films plays an important role. It not only affects the formula structure of film products, but also affects the production process before and after production. Generally speaking, there are several important factors that affect heat sealing. Heat seal temperature, heat seal strength and heat seal layer thickness are interrelated. Heat seal temperature affects heat seal strength. The thickness of the heat-sealing film in the heat-sealing layer plays an important role in the heat-sealing effect.

Heat sealing performance is an important performance of plastic packaging film. GBB-A1 electronic heat seal Tester can accurately measure the suitable heat sealing temperature range, heat sealing speed and heat sealing pressure of heat sealing compounds such as plastic film substrates, flexible packaging composite films, coated paper, and aluminum foil.

Film heat sealability test:

(1) The heat-sealing strength index of heat-sealing BOPP film in GB/T10003-2008 is ≥2.0N/15mm.

The test method is as follows: cut 5 samples evenly along the width direction of the film roll, the sample width is (15 ± 0.1) mm, and the length is 150 mm. During the test, the sample is folded in half, and the two are aligned and placed on the welding surface of the heat sealing machine for heat sealing. The heat sealing conditions are temperature 135 ℃, time 18, pressure 1.810 °Pa, aluminum-gold-gold. Place the sample straight with the heat-sealed part as the center line, and clamp the two ends of the sample on the two fixtures of the testing machine . The longitudinal axis of the sample should coincide with the centerline of the upper and lower grips and should be tight enough to prevent the sample from slipping and breaking in the grips. The distance between the clamps is 100mm, the test speed of the tensile machine is (100 ± 10) mm/min, and the maximum load when the sample breaks at the heat seal is read. If the sample is not broken at the heat seal, the sample is invalid and another sample should be taken for replacement. The result is the arithmetic mean of 5 samples, expressed in N/15mm.

(2) B/T000-2008 heat-sealing pearlescent film heat-sealing strength index ≥ 1.8N / 15mm, heat-sealing conditions 130-140 ℃, time 1, pressure 0.18MPa, tensile speed (100 ± 20) m/min.

(3) CB/T19787-2008 packaging material polyolefin heat shrinkable film heat seal strength index ≥ 9.0N /15mm.

The test method is as follows: longitudinal and transverse samples are heat-sealed. The heat sealing conditions are temperature (140 ± 5) ℃, pressure 0.18MPa, time 19. According to the QB/T2358 standard, the heat seal strength test adopts a long strip sample. The sample width is (15 ± 0m), and the tensile speed is (25050) mm/min. The results are averaged with one decimal place.

(4) Heat sealability test of PE and PP inner layer heat seal materials.

Generally, according to the customer's requirements, the initial heat-sealing temperature of the purchased inner layer materials PE and P, which are commonly referred to as low-temperature heat-sealing materials, will be put forward. The heat-sealing test of the inner layer material can be carried out by gradually increasing the heat-sealing temperature (for example, 3 ℃ each time), and using a tensile machine to test the strength of the heat-sealing temperature at different heat-sealing temperatures, according to the change of heat-sealing strength Determine the initial temperature of the material, and directly observe the relationship curve between heat-sealing temperature and heat-sealing strength if necessary.