How are plastic beverage bottle caps printed?

We now mainly have top pad printing, silk screen printing, aluminum cover flexo printing, roll printing, hot stamping, embossed positioning hot stamping, spraying.
Pad printing is aimed at the top, like a stamp, dipped in material, and then moved to the top of the lid to stamp the logo. For example Si Te top.
Screen printing, for the side, the full name is screen printing, which is a small mesh cloth with paint on it, and the cover is rolled from the bottom, and the pattern leaks on it. Generally, silk screen printing is characterized by large particles and strong three-dimensional effect.
For flexo printing, the colors are complicated, and the current Chinese aluminum cover technology can only achieve the effect of "colorful ink painting", which will be slightly distorted.
Roll printing, for the side, both plastic cover and aluminum cover. However, there is only roll printing on aluminum caps in China, and Guala, Italy, the largest bottle cap factory in the world, has roll printing on plastic caps.
Regardless of domestic or foreign countries, the automatic roll printing equipment basically comes from OMSO in Italy. Roll printing is similar to silk screen printing, in that the cover is rolled around the bottom, the only difference is that roll printing can realize large-area patterns. Hot stamping, side, top, aluminum cover, plastic cover are all available. It's just shiny paper on top, rolling around under the cover, and stamping the pattern on the top of the machine.
The world's advanced equipment manufacturer is Madag, Switzerland.
Embossed positioning hot stamping is an upgraded version of hot stamping. The top of the lid is raised, and the spot must be identified to be hot on the raised.
Spraying, top, side, aluminum cover, plastic cover are all available. The spraying machine room is very large, and the covers are lined up to go in. It is like raining in a small area in a single room, and the sauna room is dry, and sometimes it needs to be sprayed on both sides. Refer to Maopu tartary buckwheat, the spraying color is bright and uniform, and the inside of the inner cover is the original color of the plastic, which can also be used to distinguish whether to use second-hand or recycled materials.