Quality problems and solutions for the production of packaging bags
In daily life, bags can be seen everywhere, and various food packaging bags, electronic packaging, and aluminum foil packaging bags are numerous. A good bag is also tempered. What problems will you encounter in the process of making bags? How to solve it?
1. The thickness of the substrate is not uniform, and the film difference is too large.
2 The substrate is unwound and deflected.
3. When the amount of glue is too much or insufficient, interlayer sliding will occur; uneven coating will also cause local wrinkles.
4. The adhesive is not dry enough, the residual solvent is too much, the adhesion is small, and the two substrates after the composite are displaced.
5. The composite film receives the roll without cooling or cooling, and the high temperature soft composite film is easy to wrinkle.
6. The tension composite pressure is not set properly.
7. The tension is not properly controlled, and the tension of the loading and winding is not coordinated or matched.
8. Each guide roller is not parallel.
9. The surface of each guide roller is not clean, there is foreign matter sticking, or the surface of the guide roller is not flat, and there are pits, scribes, bumps, and the like.
1. Replace the qualified film.
2. The position of the film is neglected so that it does not deflect during the transfer.
3. Adjust the amount of glue applied and apply glue evenly.
4, adjust the process parameters, so that the adhesive can be fully dried, reducing the residual amount of solvent.
5, the composite film should be fully cooled before rewinding.
6. Adjust the composite pressure.
7 Adjust the unwinding and winding tension so that the tensions of the parts match each other.
8. Adjust the parallelism of each guide roller.
9. Clean the surface of each guide stick and replace the damaged guide stick to ensure that the surface of the guide roller is smooth, smooth and clean.
The bag is sticky
1. During the printing process, the drying speed of the ink is not suitable for the printing speed, so that some of the solvent remains in the printed ink layer, so that the ink layer is softened, so that the composite film is also sticky.
2, the adhesive is not completely dried, the residual solvent gradually penetrates into the ink layer, so that the ink layer is softened and sticky.
3. The plasticizer in the plastic film migrates to the ink layer, thereby softening and tackifying the film.
1. Adjust the drying speed of the ink according to the actual situation and make it fully dry.
2, adjust the process parameters to ensure that the adhesive can be fully dried, so that the amount of residual solvent is kept to a minimum.
3, replace the plastic film
The bag has "small pockmarks"
1. There are impurities in the adhesive. There is too much dust in the air in the workshop environment. There is also dust in the hot air blown out in the drying tunnel after the glue is applied. The dust adheres to the rubber layer and is sandwiched between the two base films.
2, the two-component reactive adhesive solvent is easily affected by temperature and becomes white and turbid, resulting in an increase in "small pockmark"
1. Filter the adhesive; keep the environment clean; keep the rubber bucket and glue tray clean; remove the dust from the hot air with a high mesh filter or other filter material at the air inlet of the drying tunnel.
2, "cloudy white" glue can not be used again.
Aluminized packaging bags have poor peel strength
1. The aluminum layer of the aluminized film has poor adhesion and is easy to fall off.
2. The surface tension of the aluminized film is too low.
3, the type of adhesive is not appropriate.
4, the adhesive is not dry enough, residual ethyl acetate penetrates into the ink layer, so that the printing ink softens, loosens, and even delaminates
5, the amount of glue is insufficient.
6. The purity of the diluent ethyl ester is not high, and the content of active substances such as water or alcohol is too high, and a part of the curing agent is consumed, resulting in an inappropriate ratio of the main agent to the curing agent in the adhesive.
7. The temperature of the surface of the composite steel roll is low, or the composite pressure is too small.
8. The composite film is not fully cured.
1. Replace high quality aluminized film.
2. Corona treatment of aluminized film or replacement of aluminized film.
3, select aluminum alloy film special adhesive.
4, adjust the composite process, increase the drying temperature of the drying tunnel, or reduce the speed of the composite line to ensure that the rubber boots can be fully dry.
5, appropriate increase in the amount of glue.
6. Replace the qualified thinner and strengthen the detection of the thinner.
7. Appropriately increase the surface temperature of the composite film roll or increase the composite pressure.
8. Appropriately increase the curing temperature to ensure that the composite film can be fully cured.
Aluminized bags appear spots
1. Adhesive is improperly selected. Ordinary adhesives have poor affinity for the aluminized layer and poor coating performance. If the coating is not uniform, speckle will occur.
2. There are many residual solvents in the glue. After the printing film is compounded, the ink layer is infiltrated by the residual solvent in the glue to produce speckle. 3, the ink coverage is insufficient. Especially for light-colored inks, light passes through the ink layer and is reflected back by the aluminum layer to produce spots.
4, the amount of glue is insufficient or the glue is not uniform, the composite film contains bubbles
1. Use special adhesive for aluminized film.
2. Appropriately increase the drying temperature of the drying tunnel, or reduce the speed of the composite line appropriately. Ensure that the adhesive is fully dry.
3, from the choice of strong hiding power or thick ink ink layer.
4. Appropriately increase the amount of adhesive applied to the adhesive and check the state of the rubber pressure roller to ensure uniform coating.
Dongguan Bite Packaging Materials Co., Ltd. is a large-scale company specializing in the production of food-grade composite packaging. It is a professional composite packaging bag manufacturer that uses new equipment to produce packaging bags and film rolls to provide comprehensive, environmentally friendly and safe packaging services for the market. The company produces composite bags, film, fruit bags, aluminum foil bags, nozzle bags, stand-up bags, zipper bags, anti-static bags, shaped bags, etc., suitable for food, daily chemicals, electronics, toys, medicine, cosmetics, industrial products, etc. Internal and external packaging for various industries. We adhere to the business philosophy of good faith cooperation, high quality and considerate service, and have been recognized by the industry. Our products are sold all over the world. Welcome friends from all walks of life to inquire, visit our factory for inspection and business negotiation.