Using the principle of high-frequency welding by high frequency heating the mold parts, plastic welding reach with plastic, plastic with paper cards, paper or plastic cards with paper card access.
simply put
Heat is a kind of connection with the blister paper card, paper cards usually are welded in the printing surface is coated with PVC or APET, PETG glue under the effect of high-frequency melt into one. Commonly known as the oil, according to the type of oil on the material of the blister. More typical is the battery packaging.