The difference between offset printing and silk printing? Why do plastic tubes need silk printing? Why offset printing?

Screen printing is the process of printing the positive ink through the mesh on the screen cloth to the substrate under the screen cloth.
Offset printing is a flat plate, with ink on the graphic part, and then transferred to the rubber cloth. The printing material contacts with the rubber cloth, and finally there are pictures and texts on the printing material.

The ink layer of screen printing is thicker, the color concentration is very strong, the color block of printing is thicker, and the dots are only on-line poor. It is suitable for printing panel and other products.
Offset products are bright in color and strong in dot reproduction. They are suitable for printing colorful products with rich common colors and brilliant colors.