Inkjet Cover Film can be used in many applications. Some printable transparent film products have transparent overlay, transparent film and separation effects. Other ink-jet transparent films have a stronger, more fog-like surface coating that can accommodate the high black ink density required to reproduce the positive and negative images required for other screen printing and other types of printing processes. Inkjet Cover Film with removable/relocatable adhesives.
The processing procedure of Inkjet Cover Film is one of the special processes of flexible printed board manufacturing. Covering layer processing methods include Inkjet Cover film, screen leakage of covering layer and photosensitive coating layer. Recently, newer technologies have been introduced to expand the selection range.
Inkjet Cover Film is the earliest and most widely used technology for flexible PCB cladding. It is coated with the same adhesive on the same film as the base film of copper foil laminate to make it into a semi-cured sticky conjunctiva, which is sold and supplied by the manufacturer of copper foil laminate. When supplying, a release film (or paper) is attached to the adhesive film. Epoxy resin adhesives in the semi-curing state will gradually solidify at room temperature, so they should be kept in low temperature and refrigerated. The manufacturer of printed circuit should always keep them in a refrigerated warehouse around 5℃ or send them to the manufacturer before use. The general material manufacturer guarantees 3 to 4 months of use, or 6 months if refrigerated. Acrylic adhesives can hardly cure at room temperature. Even if they are not kept in cold storage, they can be used for more than half a year. Of course, the laminating temperature of the adhesives must be very high.
One of the most important issues in the processing of Inkjet Cover film is the flow management of the adhesive. Before the inkjet Cover Film leaves factory, the material manufacturer adjusts the fluidity of the adhesive within a specific range. Under appropriate refrigerated storage conditions, the service life of the adhesive can be guaranteed for 3 to 4 months. However, within the validity period, the fluidity of the adhesive is not fixed, but gradually decreases with time. Generally, the covering film just out of the factory has a great fluidity of adhesive, and the adhesive is easy to flow out and contaminate the terminal part and the connecting plate during lamination. At the end of its service life, the flow of the adhesive is minimal or even non-existent. If the lamination temperature and pressure are not high, the Inkjet Cover film cannot be filled with graphic voids and high bonding strength.