According to different products, the coating method is also different. At present, the coating methods of release film are roughly divided into: roller coating, mesh coating, scraper coating, and non-contact coating. Let's follow the editor of the release film manufacturer to see the characteristics of each of these release film coating methods.

Release film coating method 1: scraper coating

Scraper type coating often results in uneven gluing, which is mainly related to the processing accuracy of the scraper, the installation method of the scraper, the angle of the scraper to the back glue wheel during coating, and the viscosity of the coating. The precision requirement for the flatness of the scraper is high, which means that the scraper does not warp, deform, or have gaps, otherwise the coating amount error will be large. It is understood that during coating, the angle between the scraper and the tangent line of the upper rubber wheel is generally between 15o and 30o. If it is too large, it will almost touch the back rubber wheel. When the back rubber wheel is running at high speed, the scraper is prone to vibration, causing uneven coating and large differences in coating amount. In addition, it will also cause the coated film surface to be uneven and have scratches, and it is also easy to cause damage to the blade of the scraper.

Release film coating method 2: smooth roller coating

This type of coating adopts two or more roller transfer coating methods, adjusting the gap and speed ratio between each roller to adjust the size of the coating amount. The structure of the whole coating head is relatively complex, requiring high processing and assembly accuracy of the gluing roller, coating roller, traction roller, and scraper, and high cost. Due to the use of high-precision single sticks for coating and gluing in this coating machine, the coating effect is good. In addition to adjusting the coating amount through the gap between the gluing roller and the coating roller, it can also be flexibly controlled through micro adjustment of the coating scraper, resulting in high coating accuracy.

Release film coating method 3: web roller coating

This type of coating equipment mainly uses a mesh coating stick for gluing, which has good coating uniformity and accurate coating amount. However, the disadvantage is that the coating amount is difficult to adjust. When coating with Anilox, the coating amount is related to the concave hole depth of the Anilox and the characteristics of the glue itself.

Release film coating method 4: non-contact coating - spray coating and curtain coating

Curtain coating and spray coating are two non-contact coating technologies used in paper industry, both of which belong to new coating methods.