Gravure Type Hot Melt Coating Machine

Application Range: Selective Coating, Dot coating, Pattern Coating on Film, Fabric, Textile, Paper & Lamination ...etc.

This coating can be done with various methods. Commonly it was done with reverse roller coating or gravure coating.  Gravure coating gives uniform coating but the disadvantage of this coating type is every time you have to change the engraved roller for different grammage of coating. In roller coating the challenge was to achieve thin coating and high speeds. The rotating roll churns the Hot melt and forms bubbles. This results in spotted coating.

In both these processes the molten adhesive is exposed to the air and loses its heat so the hot melt adhesive changes its viscosity and this results in variation of coating thickness. Normally the ends of the coating roll lose heat compared to the centre of the roll hence the coats more grammage at the sides and less at the centre of the web.  Sometimes the coating roller gives fumes due to high temperatures of the roller and thin layer of the adhesive on the roller hence the hot melt degrades due to high temperatures and loses its sticking property.