[China Packaging Network News] Standing bag delivery product information more eye-catching and faster, so stand out in a variety of packaging forms. The most commonly used film for pasteurization stand-up pouches is PET-NY, and what are the ingenious aspects of the two-material printing process?
PET thin film, easy to wrinkle
The PET film can easily generate large static electricity, resulting in blockage, ink dot, knife line and other quality problems during printing. In addition to the conventional method of removing static electricity, it is an effective method to strengthen the temperature and humidity control of the workshop.
When printing, a large tension is required, and a special ink resistant to high temperature cooking is selected, and it is necessary to always pay attention to whether the film is electrostatically charged.
NY easy to absorb moisture deformation, tension is extremely unstable
When the film is not printed, the packaging film must not be damaged. Before the printing, the humidity of the test environment should be taken into consideration. The dehumidification measures should be taken. After opening the packaging film, it must be printed immediately. At the same time, one process can not be ignored - preheating, and the preheating temperature is controlled at 50~ 80 °C, no preheating equipment can be flexibly used in printing equipment, the first color group can be vacated as preheating device; the tension during the printing process should be properly reduced; after printing, it must be sealed and put into curing room for aging 2～3. Days, compounded as soon as possible.
The focus of control is ink
Whether printing PET or printing NY, the focus of control is ink. It mainly includes the following two aspects:
1. Adjustment of ink printability. Including viscosity, color concentration adjustment. Viscosity automatic regulator can be used to adjust to improve work efficiency. The regulator can add the solvent according to the preset value to keep the viscosity of the ink unchanged. However, the color concentration of the ink should not be diluted with a solvent, use a special diluting agent to adjust.
2, closely monitor the impact of active particles. After a certain time of printing, the ink will produce many active groups, these groups will be combined with the chromium ion of the gravure cylinder. When these binders appear in the shallow part of the graded version, their binding force will hinder the transfer of the ink. Causes blockage and flowering. Therefore, the manufacturer must not worry about the cost at this time, and an appropriate amount of the activity-reducing agent CHY-1 adjuvant can be added.