In addition to displaying the product information, all products with outer packaging sold on the market generally need to print physical patterns on the outer packaging in order to improve consumers' purchase desire. Different printing methods are also used for different printing packaging materials. The printing methods are as follows:

1. Relief printing

Relief printing is also known as embossing. The words and patterns on the printing plate are convex. When printing, ink is brushed on the printing plate, and then the ink on the words and patterns is pressed onto the printed object by pressure. Type printing plate, zinc printing plate and copper printing plate are hard relief plates; Rubber plate, plastic plate and resin plate are flexible relief plates, so flexible relief printing is also called flexographic printing. Although relief printing is not as delicate as the pattern printed by gravure printing, it has many advantages, such as small land occupation of printing equipment, fast printing speed, low plate making cost, low ink consumption, no benzene residue, and the environmental pollution of alcohol-soluble ink and water-soluble ink used in relief printing is also small.

2. Gravure printing

Gravure printing is that all printed patterns and words are concave on the printing plate. During printing, it is necessary to pour ink, dip ink or transfer ink on the printing plate, then scrape the excess ink on the printing plate with a scraper, and then apply appropriate pressure to the printed object (paper or plastic film) between the embossing roller and the printing plate through the embossing roller, so as to squeeze the ink in the concave surface of the printing plate onto the printed object, so as to achieve the purpose of printing, Traditionally, it is called gravure printing.

3. Lithography (pad printing or offset printing)

The graphic and blank parts of lithography on PS plate are almost on the same side. Because of the different plate making processes, there are positive and negative plates. It uses the principle of oil and water phase exclusion to inject glue into the blank of the printing plate, and then print indirectly with blanket, so it is also called pad printing. It is also called offset printing because the words and patterns on paper and film come from blanket. At present, offset printing is only implemented on PP sheets of 0.014 ~ 0.04mm.

4. Screen printing

Screen printing is referred to as screen printing. The patterns and characters on the printing plate are hollowed out, that is, the ink leaks from the hollowed out place to form graphics and text, so it is also called missing printing. This kind of printing has a strong three-dimensional sense and can be printed on special-shaped surfaces. The range of printed objects is very wide.

At present, flexible packaging materials are mostly used for intaglio printing. Such printing products have the advantages of gorgeous color, full color and realistic physical objects. Yihai packaging has accumulated experience in flexible packaging printing and is constantly studying. It is developing the use of water-based ink for intaglio printing, which has been improved in environmental protection compared with the traditional oily ink. Yihai packaging advocates the concept of "green, environmental protection and health", Provide customers with high-quality packaging products.