How many layers can have a multilayer film? The answer is clear to all, as the title you can see that the film may have two or even more layers. The extrusion process - the application layer, is very complicated and requires a lot of costs (expensive equipment), but even more investment requires a process such as co-extrusion - the simultaneous imposition on the basis of several layers. Installation of equipment for these processes requires a very large investment on the part of the owner, but soon it pays off and makes a pretty good income. However, a large number of manufacturers to easily cope without professional equipment.

There are two methods of applying layers on the basis of the film "direct method" and the "primary coating method."

"Direct method" is applied to the glue layer directly on the substrate material. It is used in the manufacture of a cheap film, and a thin film which has poor adhesive ability and breaks under the action of its power of 2 kg/cm2. The only advantage is the low cost.

By "primary coating method" is executed application on the base material at the same time the "primary coating" (intermediate layer) and an adhesive layer. This process is quite complex, but manufactured product has very good adhesive capacity and decreases the likelihood that the film may peel off. The strength at break equal to 4 kg/cm2. The only drawback of this film - the high cost, but as they say, avaricious pays twice.

Do not forget that when choosing a multi-layer film is better to buy the one in which the foundation is thicker adhesive layer, because the larger the ratio, the better it will be.