Common Problems and Solutions in Clothing Packaging Bag Production

Consumers often focus on the aesthetics of garment packaging and the information on it. However, professional flexible packaging manufacturers, such as Shunxingyuan Packaging, pay more attention to packaging materials and production processes, and may unintentionally look for printing defects, such as the accuracy of overprinting, whether small text and lines can be clearly seen at the edges, etc.

For Garment Packaging Bags Common problems and solutions summarized by Shunxingyuan Packaging, a professional flexible packaging manufacturer, are as follows:

1. Inaccurate Overprinting

⑴ Equipment reasons: During long-term production, some major parts of the equipment wear out, such as the wrong installation of the head, bending of the printing shaft, wear of the gear teeth, damage caused by lack of lubrication of the sleeve shaft, and unevenness of the traction roller, which can affect the accuracy of overprinting.

⑵ Uneven pressure of each color on the printing plate roller, uneven pressure on the left and right ends of the printing plate roller, and looseness of the printing roller can cause inaccurate overprinting.

⑶ Process technology aspects: Imbalance in the control of unwinding and rewinding tension, operational errors, and inappropriate wind and heat. Tension imbalance affects the accuracy of overprinting.

⑷ The specifications of each set of plates do not match (exceeding the normal error range), causing inaccurate overprinting.

⑸ High ink viscosity affects the accuracy of overprinting.

⑹ Changes in film properties (uneven thickness) affect constant tension, causing inaccurate overprinting.

⑺ Subjective factors: Printing operators must be responsible, focused, and operate carefully during normal production, inspect product quality, and promptly identify and solve problems.

2. Ink Adhesion

⑴ Solvent problems: Due to improper solvent ratio, slow volatilization, the presence of small amounts of high-boiling substances such as cyclohexanone and butanol in the solvent, and poor resin release from the solvent.

⑵ Equipment aspects: Insufficient hot air volume of the drying device, improper use of hot and cold air, and too high speed.

⑶ Plate making aspects: The depth of the printing gravure roller is too deep.

⑷ Ink aspects: The ink is too thick, and the plasticizer content in the ink is too high.

⑸ The traction roller is pulled too tight, and the rewinding tension is too high.

⑹ Film aspects: Additives in the film are soluble in the solvent, affecting solvent release, and corona treatment is not performed or does not reach the required surface tension index.

⑺ High temperature, high humidity, and high pressure environmental factors cause ink adhesion.

3. Incomplete Pattern Lines

⑴ The ink dries too quickly, causing the plate to dry out.

⑵ Excessive wind and heat affect the drying of the concave surface of the printing roller.

⑶ The plate making etching is too shallow, and the ink adhesion is low.

⑷ The pressure between the printing roller and the embossing roller is too light.

⑸ The distance between the doctor blade on the printing roller and the printing point is too far (the reverse doctor blade of the drum machine is prone to drying out the plate).

⑹ The speed is too slow.

4. Line Scratches

⑴ There are hard particles and impurities at the place where the doctor blade is close to the surface of the printing roller. They must be removed in time. For non-fixed line scratches, simply sharpening or replacing the blade is sufficient.

⑵ If the lines are fixed, there may be hard impurities embedded in the dots of the printing roller, and the machine must be stopped to remove them.

⑶ When a new plate roller starts printing, fixed line scratches are generally caused by the unpolished surface or repair pinholes after chrome plating of the printing roller.

⑷ If the resin and pigment in the ink are not finely ground, it will also cause line scratches. The impurities in the dots must be removed with a copper wire brush, filtered with a 120-mesh copper wire mesh, and then printed.

⑸ The angle, position, hardness, and thickness of the doctor blade must be adjusted appropriately.

There are many other factors that affect product quality during plastic gravure rotary printing. Only by combining the actual situation of on-site equipment and raw and auxiliary materials in printing practice can solutions be found.

Long press the QR code to follow, Customize your exclusive packaging

www.dgsunpak.cn Garment Packaging Bags