1.Hot Foiling
Hot foiling is the process of transferring metallic foil to paper or other materials using heat and pressure. This technique uses high temperatures and pressure to adhere a thin layer of metal foil to the packaging surface, creating exquisite metallic texture patterns or text.
2.Flat Foiling
Flat foiling is the most commonly used foiling technique where only the content to be foiled is metallic, leaving other areas blank or printed. The aim of flat foiling is to highlight the foiled areas, typically important information in gold. Compared to other processes, flat foiling is less challenging and has fewer chances of errors. Additionally, being the simplest foiling technique, it causes less damage to the paper.
3.Reverse Foiling
Reverse foiling is the opposite of flat foiling, using metal to highlight the white space. The usual practice is to surround the graphics and text meant to be highlighted with a large, foil-stamped shape, leaving the highlighted graphics and text as a void. This creates the reverse foiling effect. For reverse foiling, the lines of the graphics to be highlighted should not be too fine, or the final product might not turn out as desired.
4.Speed Control in Lamination
Lamination of printed paper with plastic film (BOPP) occurs on a conveyor belt. The speed of the lamination machine determines the dwell time of the paper and film at the heat pressing interface. When temperature and pressure are fixed, changes in conveyor speed can affect the lamination outcome.
Too fast a speed can result in weak adhesion between the paper and film, potentially causing a foggy appearance. Too slow a speed reduces efficiency and increases the likelihood of bubbling. Based on practical experience, lamination speed is generally kept between 20 to 39 feet per minute, roughly equivalent to about 20 sheets of paper.