Spout pouch has the characteristics of easy pouring and absorbing the contents inside, and can be opened and closed repeatedly. In the field of liquid and semi-solid, it is more hygienic than zipper bags and more cost-effective than bottled bags, so it has developed rapidly and is very popular in the international market. Commonly used It is suitable for the packaging of beverages, detergents, milk, chili sauce, jelly and other products.
There are many problems in the actual production of stand up spout pouch, but there are mainly two prominent problems: one is the leakage of liquid or air when the product is packed, and the other is the uneven bag shape and asymmetric bottom seal during the bag making process. . Therefore, the correct choice of Spout pouch material selection and process requirements can improve the characteristics of the product and attract more consumers to rely on it.
1. How to choose the composite material of Spout pouch？
The common spout pouch on the market is generally composed of three or more layers of films, including an outer layer, a middle layer and an inner layer.
The outer layer is the printed material. At present, the commonly used vertical package printing materials on the market are cut from ordinary OPP. This material is usually polyethylene terephthalate (PET), and PA and other high-strength and high-barrier materials. choose. Common materials such as BOPP and dull BOPP can be used to package dry fruit solid products. If packaging liquid products, PET or PA materials are generally used.
The middle layer is generally made of high-strength, high-barrier materials, such as PET, PA, VMPET, aluminum foil, etc. The middle layer is the material for the barrier protection, which is usually nylon or contains metallized nylon. The most commonly used material for this layer is metallized PA film (MET-PA), and RFID requires the surface tension of the interlayer material to meet the composite requirements and must have a good affinity with the adhesive.
The inner layer is the heat-sealing layer, which is generally made of materials with strong low-temperature heat-sealing properties such as polyethylene PE or polypropylene PP and CPE. It is required that the surface tension of the composite surface should meet the composite requirements, and should have good anti-pollution ability, anti-static ability and heat-sealing ability.
Besides PET, MET-PA and PE, other materials like aluminum and nylon are also good materials for making Spout pouch. Common materials used to make Spout pouch: PET, PA, MET-PA, MET-PET, Aluminium Foil, CPP, PE, VMPET, etc. These materials have multiple functions depending on the product you want to pack with Spout pouch.
Spout pouch 4 layers material structure: PET/AL/BOPA/RCPP, this bag is a Spout pouch of aluminum foil cooking type
Spout pouch 3-layer material structure: PET/MET-BOPA/LLDPE, this transparent high-barrier bag is generally used for jam bags
Spout pouch 2 layer material structure: BOPA/LLDPE This BIB transparent bag is mainly used for liquid bag
2. What are the technological processes of manufacturing Spout pouch？
Spout pouch production is a relatively complex process, including multiple processes such as compounding, heat sealing, and curing, and each process needs to be strictly controlled.
（1） Printing
Spout pouch 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 the nozzle part is generally not printed with matte oil. Because of the differences in the temperature resistance of some domestic dumb oils, many dumb oils are easy to reverse stick under the high temperature and high pressure state of the heat sealing position. At the same time, the heat sealing knife of the general manual pressure nozzle does not stick to the high temperature cloth, and the anti-stickiness of the dumb oil is easy to accumulate on the pressure nozzle sealing knife.
（2）Compounding
Common glue cannot be used for compounding, and glue suitable for high temperature of the nozzle is required. For Spout pouch that needs high temperature cooking, the glue must be high temperature cooking grade glue.
Once the spout is added to the bag, under the same cooking conditions, it is likely that the final pressure relief during the cooking process is unreasonable or the pressure retention is insufficient, and the bag body and the spout will be swelled at the joint position, resulting in bag breakage. The package position is mainly concentrated in the weakest position of the soft and hard binding position. Therefore, for high-temperature cooking bags with Spout, more caution is required during production.
（3） Heat sealing
The 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 hot stamping and the size of the heat sealing area. In general, when the same part is hot pressed more times, the heat sealing temperature can be set lower.
Appropriate pressure must be applied during the heat sealing process to promote adhesion of the heat cover material. However, if the pressure is too high, the molten material will be squeezed out, which not only affects the analysis and elimination of bag flatness faults, 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 to the performance of the heat sealing material, the heating method and other factors. The specific operation should be adjusted according to the different equipment and materials in the actual debugging process.
Post time: Sep-03-2022