In the current market, packaging bags have become one of the necessities for sale. Aluminum foil bags are widely used in food, medicine, cosmetics and other fields because of the advantages of avoiding light and retaining fragrance. But the aluminum foil bag may face the problem of cracking, affecting the use effect. Today giant packaging for you to analyze the influence factors of aluminum foil packaging bag heat sealing strength. I hope this will give you more to think about.
There are 6 factors affecting the heat sealing strength of aluminum foil bag.
1. Raw and auxiliary materials -- the original aluminum foil is the carrier of the adhesive layer, and its quality has a deep impact on the heat sealing strength of the product. On the one hand, the oil on the surface of the original aluminum foil will weaken the adhesive between the original aluminum foil. On the other hand, the heat sealing strength is also affected by the metal composition and surface luminosity of the original aluminum foil. So we should strictly put the quality of the original aluminum foil.
2. Adhesive -- adhesive is a special substance containing solvent. It is coated on the dark side of the original aluminum foil under certain technological conditions, and forms an adhesive layer after drying, which plays a decisive role in the heat sealing strength of the product.
3. In terms of production technology -- under the control of certain process parameters, the adhesive is coated on the surface of the original aluminum foil to form a film. The quality of the film will directly affect the heat sealing strength of the product. The more important parameter is coating speed. If the coating speed is too fast and the temperature of the drying channel is too high, the solvent on the surface of the coating will volatilize too fast, resulting in residual solvent in the film, and the drying of the coating film will not be sufficient, which will affect the heat sealing strength of the product.
4. Heat sealing temperature -- heat sealing temperature is an important factor affecting heat sealing strength. If the temperature is too high, the bonding between the adhesive layer and the pvc film is not strong. If the temperature is too high, the medicine will be affected. Therefore, the reasonable heat sealing temperature is generally between 150℃ and 160℃.
5, heat sealing pressure - to achieve the ideal heat sealing strength, it is necessary to set a certain heat sealing pressure. If the pressure is insufficient, it can not make the adhesive layer of aluminum foil bag products and pvc film fully fit heat sealing, so it can not achieve good heat sealing effect. Therefore, the national standard stipulates that the heat seal pressure is 0.20.2×10Pa.
6, heat sealing time - heat sealing time will also affect the heat sealing strength. Under normal circumstances, under the same heat sealing temperature and pressure, a longer heat sealing time can make the heat sealing part sealed more firmly and perfect. It can better achieve the expected heat sealing strength. If the heat sealing time is too short, it will make the heat sealing between the bonding layer and pvc film is insufficient. For this reason, the national standard sets the scientific heat sealing time as 1s.
Therefore, different packaging materials used in the production of aluminum foil bags need different heat sealing parameters in actual production, so it is necessary to adjust the heat sealing parameters reliably according to the actual production needs and product packaging performance requirements. It should also be noted that under different heat sealing pressure, time and temperature, other heat sealing parameters that can meet the standard are not the same, and should be adjusted according to the actual situation to ensure the heat sealing strength and quality of aluminum foil bag.
Attention should also be paid to the cooling process of the aluminum foil bag after heat sealing. When the weld that has just been melted and heat-sealed is formed at a low temperature, the heat-sealing strength of the aluminum foil bag may be reduced due to poor cooling, and the appearance of the weld will be affected, resulting in unqualified products. Generally, poor cooling of aluminum foil bag may be caused by insufficient heat sealing pressure, poor cooling water circulation, high water temperature or timely cooling.
In addition, the products to be contained in the aluminum foil bag will also affect the heat sealing strength of the aluminum foil bag. For example, when using aluminum foil bag to pack fine powder products, it is easy to stick the sealing of aluminum foil bag. At this point, it is necessary to reasonably adjust the thickness of packaging materials and inner materials of aluminum foil bag according to the products to be packaged, so as to ensure and improve the heat sealing strength of aluminum foil bag.
