When solvent-free compounding, there are many main reasons for the longitudinal dead folds of solvent-free composite films, and solvent-free equipment has strict requirements for substrates. During the compounding process, it is recommended to do some treatment.
Reasons for longitudinal dead folds of solvent-free composite membranes :
l  The thickness of the film is uneven, and the curl is wrinkled. High-quality films should be used.
l  Sagging caused by dampness of the film or different ink on the printed surface. Take moisture-proof measures for films that are susceptible to moisture; adjust the winding tension for films with large printing sags.
l  Too much coating.
l  Printing substrate, adhesive layer and composite substrate expansion and contraction deviation.
l  Improper tension control.
Responses:
1. Increase the unwinding and winding tension, the two should cooperate with each other to prevent shrinkage.
2. Open the pre-heating film at the main unwinding position and the auxiliary unwinding position to make the two films soft, so as to reduce the stress of the combined film.
3. Increase vehicle speed. In order to meet the needs of high-speed production when the solvent-free equipment is designed, each guide roller has a guide groove, and the guides of the two adjacent rollers are exactly opposite. This is for better flattening during high-speed compounding. In addition to this, high-speed coating can also be taken up before the film is wrinkled. At this time, it should be noted that in order to prevent poor coating effect at high speed, the temperature of the rubber roller should be increased to ensure quality.
Guangzhou serika Technology Co., Ltd. , https://www.serikamedical.com