Discussion on Screen Printing Quality of High-grade Wrinkle Ink (I)

At present, with the rapid growth of commodity economy and the diversified development of printing technology, packaging and decoration printing products have entered a new development realm in China. In the past 20 years, the share of packaging and decoration printing in total printing output has increased from about 20% to about 70%, which is the highest in China's printing industry. Although lithography, letterpress, and gravure printing are the main printing technologies for packaging, decorating, and printing products, due to the complexity of the technical process of packaging and decorating printing products and special quality specifications, special printing processes must be used. This process accounts for the output value of packaging and decoration printing. 5% to 10%, while the application of screen printing is to meet this trend, to fill the blank packaging and decoration printing.

From the market division, screen printing is not a major printing process in the field of packaging and trademark anti-counterfeit printing. However, according to the recent development of the domestic and international packaging market, it can be seen that screen printing has appeared in the field of anti-counterfeiting packaging printing. With steady growth, screen printing has occupied an extremely important position in the packaging and printing market with its own characteristics. Wrinkle ink is born in this trend. The ink is printed on substrates such as gold cardboard and silver cardboard. After being wrinkled and dried by UV, it will produce a special wrinkle effect on the surface due to UV wrinkle ink. With three-dimensional strong, luxurious and elegant, ink film full and good visual effects and other characteristics, its application has expanded to print high-grade tobacco packets, wine boxes, gift boxes, health products packaging boxes and other fields. However, in the actual printing process, due to the short time available for this ink, the widespread application and lack of research and discussion, UV-wrinkle ink printing quality will be affected by many factors, such as the number of screens, Stretching angle, printing pressure, squeegee angle, printing speed, drying speed, etc., if these factors are not well controlled, will inevitably affect the quality of the final product.

In addition, U V wrinkle inks are difficult to get the desired wrinkle effect after printing. This is the biggest problem in U V wrinkle ink printing. Any change in the parameters during the printing process may cause printing failure, which requires a lot of experimentation. Determine the printing conditions required for good prints.

1. experimental method

In the preliminary analysis of the factors influencing the printing quality of U V wrinkle inks (screen mesh number, stretch tension, stretch angle, sensitized film thickness, printing pressure, printing speed, squeegee angle, mesh distance and drying speed), First, conduct rough experiments, preliminary determine the most important impacts and determine its general scope; then optimize the design, determine the 16 sets of printing program; the final fine test to get the printed matter, through the analysis and evaluation of prints to draw conclusions.

2. experiment procedure

2.1 Coarse experiment

2.1.1 Specific Experiments

The main purpose of the crude experiment was to screen major factors and determine the general scope of the main factors.

The mesh parameter is set to 150 mesh;

The maximum pressure of the air pump used in the experiment was 1 Mpa, and the empirical value range during use was 0.6-0.8 MPa, so the experiment was selected to be 0.7 MPa;

At present, the commonly used methods for coating photosensitive adhesives in screen printing enterprises are three-time printing on the printing surface and one-time coating on the backside. Therefore, the printing surface coating is set to 3 times.

Coarse experiment (1); fixed wrinkle speed range fixed stretch net tension, scraper angle, printing pressure, printing speed and net distance, through the experimental determination of wrinkling speed range (see Table 1).

Coarse experiment (2): Determine the range of the fixed net length, the angle of the spatula, the printing pressure, the printing speed, and the speed of wrinkling, and determine the range of the net distance by experiment (see Table 2).

(to be continued)