The vast majority of books, catalogs and packaging color boxes are offset products. Offset lithography is a very simple, means of speaking that is offset rubber (Pib) will plate transfer to the substrate of printing, namely three roller (printing, lithographic printing and embossing of Pib), in the south of our country to the printing mode called Ke printing.
Plastic bag products are generally gravure printing. Gravure printing full color stereoscopic graphics, has the sense of convex, and rich layers, clear lines, high quality printing plate, long service life, suitable for mass printing. Gravure printing of very thin materials, such as plastic films.
The main disadvantages are: gravure printing prepress technology complex, long cycle and high cost because of the plate; volatile solvent, high content of harmful gas workshop, serious damage to the health of workers; gravure printing practitioners required treatment is relatively high.
Gravure printing complex, high prices, ink pollution environment. These two problems affect the development of gravure printing. In particular, a large number of printed matter reduction, short version requires a large number of low-priced printing pieces, gravure printing constantly lost market.
The most common logistics packaging corrugated cardboard boxes are flexo printing products. Flexo printing is the evolution of letterpress printing, flexo printing is a direct printing method, because of the use of elastic, convex image plate known as flexo printing. The flexographic plate is glued to the plate cylinder, and the plate is supplied by a carved metal anilox roller. Flexo direct printing has the following characteristics: (1) large format.
The maximum width of the wide flexo press reaches 2.5m~2.8m. (2) low price. Flexo printing is very high, can be reused; ink prices are also low. (3) linkage production, such as printing, slotting, indentation, ordering (sticky) box, bundling and other machines can be completed. (4) the carton strength is reduced less.
Because flexo printing is light pressure printing, it has little effect on the strength of corrugated paperboard. (5) the printing accuracy is not high, the conventional offset printing screen line number to 175 lines per inch, while conventional screen digital flexo carton 35 lines per inch ~65 lines per inch, which belongs to the low precision of printing, the most suitable for printing text line is printed four-color image quality in recent years has increased, but there are still limitations.
Screen printing is the closest way to print our lives. Common local UV is screen printing, according to the thickness of the screen can form ink accumulation, there is a very good three-dimensional feeling; screen printing is also widely used for self-adhesive label printing.
When I was young, our examination papers is Roneo mimeographed, teacher put the cushion in netted plate, with the sharp pen lettering lettering, and mimeograph printing.
This printing method is the same as our screen printing principle: the screen has a hollow part, the ink through the hole transfer to the substrate (paper, ceramic, etc.), to form images or text. In addition to air and water, screen printing can be printed on anything! It is said that the objects of screen printing are extensive, and the patterns on the electrical appliances are also printed on the screen.