新闻中心
Many operators find that the BOPP film surface cannot stick, and their first reaction is to add glue. In fact, increasing the adhesive amount from 40g/m ² to 80g/m ² does not increase the bonding strength by less than 20%, but instead causes overflow, waste, and slow curing. The fundamental reason is that the surface energy of BOPP film is only 30-34mN/m,hot melt adhesiveUnable to infiltrate – it’s not a lack of glue, it’s glue that can’t hold on.
The correct approachReplace with low surface energy specialized hot melt adhesive particles containing thickening resin and polar modifier, which can increase the adhesion of BOPP film by more than 3 times.
When the coating temperature was increased from 170 ° C to 200 ° C, the BOPP film wrinkled and deformed, and the adhesive liquid penetrated the film layer, causing delamination. High temperature does not equal high viscosity, exceeding the upper limit of material temperature resistance can have the opposite effect.
The correct approachThe coating temperature should be controlled at 170-180 ° C, and the opening time should be 3-5 seconds for the model to allow sufficient time for the adhesive to wet the film surface.
Some factories use universal hot melt adhesive particles to simultaneously bond kraft paper, copperplate paper, and BOPP film, resulting in only the BOPP surface being opened. The surface energy of different materials varies greatly, and targeted selection is necessary.
The correct approachBOPP film surface is individually coated with adhesive. Sunlife hot melt adhesive has BOPP specific models, and Guangzhou Sunlife Trading provides free comparative testing services. One set of samples can verify the difference in effectiveness.
Nowadays, more and more books are using EVA hot melt adhesive particles for wireless binding, and almost all large, medium, and small processing factories in China have put this technology into use. This is because the use of this book binding adhesive has the characteristics of fast binding, short operation cycle, good appearance of finished […]
Conclusion The amount of glue used is small, and there are many varieties (books, packaging, and quick printing require a little each). Buying each item alone cannot meet the minimum order quantity, and the unit price is high. Using “mixed batch and combined order” – combining multiple categories of orders from the same supplier, or […]
The quality of book binding often depends not only on the equipment and paper, but also on the binding adhesive. If a book experiences problems such as page dropping, glue peeling, stiff spine, uneven flipping, and low-temperature brittleness, it is often related to the choice of binding glue, glue temperature, paper type, and process compatibility. […]
Both new and existing users of hot melt packaging adhesive need to consider many factors when solving problems on the production line. The problem usually occurs in one of the following three aspects: equipment, adhesive, or environment. Any one or combination of these three variables could be the root cause of the problem. Some common […]
