1. Ingredients and Mixing: Mix PVC resin with plasticizers, stabilizers, lubricants, coloring agents, and other additives in proportion.
2. Extrusion blown film: The mixed raw materials are heated and melted by an extruder, and then blown into a cylindrical film.
3. Printing: Color printing (usually using gravure printing) is performed on a cylinder film to print the desired patterns and text.
4. Slitting: Cut the printed large roll film into small rolls of film according to the height requirements of the bottle cap.
5. Bag making (stamping): Cut and seal the sliced film using a bag making machine to produce semi-finished cylindrical bottle caps with one end sealed.
6. Packaging: After passing the inspection, the packaging is put into storage.
Heating shrinkage process during application:
Cover the bottle cap with the bottle mouth → use a heat shrink furnace (or a hot air gun) → shrink under heat (usually around 150 ° C) → tightly wrap around the bottle mouth → cool and shape.