All the products sold on the market with outer packaging, in addition to the need to display product information, in order to improve the consumer's desire to buy generally in the outer packaging to print physical patterns, etc., different printing packaging materials use different printing methods, printing methods are the following:

1. Letterpress Printing

Letterpress printing is also called embossing. The characters and patterns on the printing plate are protruding. When printing, ink is brushed on the printing plate, and then the ink on the characters and patterns is pressed onto the printed matter by pressure. Lead 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 flexo printing.Although letterpress printing is not as fine as the pattern level printed by intaglio printing, it has many advantages such as small footprint of printing equipment, fast printing speed, low plate making cost, less ink consumption, no benzene residue, etc., and the alcohol-soluble ink and water-soluble ink used in letterpress printing have less environmental pollution.

2. Gravure printing

Gravure printing means that all printed patterns and characters are recessed on the printing plate. When printing, ink should be poured, impregnated or delivered on the printing plate first, then the excess ink on the printing plate should be scraped clean with a scraper, and then the printed matter (paper or plastic film) between the embossing roller and the printing plate should be given appropriate pressure through the embossing roller to squeeze the ink in the intaglio of the printing plate onto the printed matter, thus achieving the printing purpose. It is customarily called gravure printing.

3. Flat panel (pad printing or offset printing) printing

The graphic and blank parts of the flat printing on the PS printing plate are almost on the same side. Because of the different plate-making process, there are Yang plate, Yin plate. It uses the principle of oil and water phase rejection to inject glue into the blank of the printing plate, and then print indirectly with a blanket, so it is also called pad printing. Also because of the paper and film on the text, patterns from the blanket, also known as offset printing. At present, offset printing is only carried out on PP sheets of 0.014 to 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 to form pictures and texts, so it is also called missing printing. This kind of printing three-dimensional sense is very strong, can be printed on the special-shaped surface, the range of printed matter is very wide.

At present, flexible packaging materials are mostly used for intaglio printing. Such printed products have the advantages of bright color, full color and lifelike objects. Yi Hai Packaging has accumulated experience in flexible packaging printing and is constantly studying. It is developing the use of water-based ink for intaglio printing. Compared with traditional oil-based ink, Yi Hai Packaging advocates the concept of "green, environmental protection and health" to provide customers with high-quality packaging products.