The nozzle bag is easy to pour and absorb the contents, and can be opened and closed repeatedly. In the field of liquid and semi-solid, it is more hygienic than the zipper bag and more cost-effective than the bottle. Therefore, it develops rapidly and becomes a popular bag type in the market. It is often used in the packaging of beverages, detergents, milk, chili sauce, jelly and other products.There are many problems in the actual production of the nozzle stand-up pouch, but there are two main problems: one is the leakage of liquid or air when the goods are filled, and the other is the uneven shape of the bag and the asymmetry of the bottom seal during the bag making process. . Today, I will analyze the material selection and process requirements of the nozzle bag, hoping to improve the overall quality of the nozzle bag.1. Selection of composite materialsCommon nozzle bags on the market are generally composed of three or more layers of film, including an outer layer, a middle layer and an inner layer.The outer layer is printed material. At present, the vertical package printing materials commonly used in the market are all from ordinaryOPPcut out, andPET,PAHigh-strength, high-barrier materials can be selected according to the situation. Common materials such asBOPPand dullBOPPCan be used to package dried fruit solid products. If packaging liquid products, generally usePETorPAMaterial.The middle layer generally uses high-strength, high-barrier materials, such asPET,PA,VMPET, aluminum foil, etc. andRFIDThe surface tension of the sandwich material is required to meet the composite requirements, and must have a good affinity with the adhesive.The inner layer is the heat seal layer, generally made ofPE,CPE,CPPIt is made of materials with strong low temperature heat sealing performance. It is required that the surface tension of the composite surface should meet the composite requirements, and should have good anti-pollution ability, antistatic ability and heat-sealing ability.2. Requirements of bag making processThe production of spout pouches is a relatively complicated process, including multiple processes such as compounding, heat sealing, and curing, and each process needs to be strictly controlled.1.printThe nozzle bag needs to be heat-sealed, so the ink at the nozzle position must use high-temperature resistant ink, and if necessary, a curing agent needs to be added to enhance the sealing of the nozzle position.It should be noted that matte oil printing is generally not performed on the press nozzle. Because there are differences in the temperature resistance of some domestic dumb oils, many dumb oils are prone to anti-sticking under the high temperature and high pressure state of the heat sealing position. At the same time, the heat-sealing knife of the general hand-pressed mouth does not stick high-temperature cloth, and the anti-sticking of dumb oil is easy to accumulate on the mouth-pressed knife.2.complexOrdinary glue cannot be used for compounding, and glue suitable for the high temperature of the press nozzle is required. For nozzle bags that require high-temperature cooking, the glue must choose high-temperature cooking grade glue.Once a suction nozzle is added to the bag, under the same cooking conditions, it is likely that due to unreasonable pressure relief or insufficient pressure holding at the end of the cooking process, swelling will occur at the joint between the bag body and the suction nozzle, resulting in bag breakage. Because the breaking position is mainly concentrated in the weakest position of the soft and hard joint. Therefore, for high-temperature retort bags with suction nozzles, more care needs to be taken during production.3.heat sealThe factors that need to be considered in setting the heat sealing temperature are: the characteristics of the heat sealing material; the second is the film thickness; the third is the number of times of hot stamping and the size of the heat sealing area. Generally, when the same part is hot-pressed more times, the heat-sealing temperature can be set lower.Proper pressure must be applied during the heat sealing process to promote bonding of the heat covering material. However, if the pressure is too high, the molten material will be extruded, which not only affects the analysis and elimination of the flatness of the bag, but also affects the heat sealing effect of the bag and reduces the heat sealing strength.The heat sealing time is not only related to the heat sealing temperature and pressure, but also related to the performance of the heat sealing material, heating method and other factors. The specific operation should be adjusted according to different equipment and materials in the actual debugging process.