Membrane bonding is a special way of creating a tamper-evident closure for jars. To this end, a membrane made from coated paper or aluminum foil, for example, is bonded to the glass rim. When the jar is opened, the bonding is broken, leaving an obvious visual indication that the jar has indeed been opened. The adhesives are derived from EVA copolymer dispersions mixed with polyvinyl alcohol solutions that allow their viscosity and open time to be adjusted, respectively. The jars are conveyed under topside gluing systems that coat the rim with adhesive. By screwing on the lid, the membrane, which has usually been placed into the lid, is pressed against the adhesive on the rim. Another option is to coat the membrane with hot-melt adhesive that is activated by infrared irradiation following closure of the jars. After cooling, the membranes securely adhere to the rims.
Membrane Bonding
2 декабря, 2015 
Pokraskin 
Опубликовано в рубрике Adhesive Bonding