Differences between multi-layer and one layer (mono) Polyethylene film

Process of co-extrusion (extrusion of multi-layer film) with the selection of special materials enables for buyer remarkable financial savings the same time the product gets better mechanical characteristics and better optical look.

Advantages of multi-layer Polyethylene film

With the proper selection of raw materials three-layer Polyethylene film gives better optical (transparency, shininess…) and mechanical (toughness) characteristics with the reduced thickness (20-30 % less thickness then mono layer film). The Polyethylene film is been sold by it weight and been used by its length and that means significant financial saving. Plus because of the reduced thickness in process of packaging buyers get more film in a roll which means fewer roll changes, less needs for storage space and less packaging waste

The process of image print on Polyethylene film

For image print on the Polyethylene film a process called flexographic printing is being used. There are 4 basic operations in the flexographic printing operation
Image Preparation.
1-Image, picture or illustration is made or transferred to digital image. Image is additionally processed and printed on special paper. Because of the simulation of print, if the customer finds that the quality of the cool poof is satisfactorily the customer gives the approval for Flexographic Plate Making
2- Flexographic Plate Making
Flexographic printing uses special made Flexographic Plate – plates with raised images (relief) made of flexible material, such as plastic and rubber. For each color one Flexographic Plate is made.
3- Flexographic Print
Flexographic Plate is attached to a special roller and trough 4 or more roller system ink (image) is transferred to the Polyethylene film.
4-Finishing
Printed Polyethylene film may run through the additional processes like cutting, folding and binding and it’s ready for transport.
For getting colored Polyethylene film (white, black, blue…), in the extrusion process the ink in the shape of granulates (master batch) is added and that film doesn’t require additional printing. Problem colors in flexo are: violet, purple, reflex blue and etc.

Corona process
Unprocessed Polyethylene have low surface energy and as such represents essentially “non- stick” plastics and isn’t good for merging (gluing) with other materials. Corona process is a process that raises the surface energy of Polyethylene film. It raises the surface energy level to approximate 38-42 dynes/cm and enables processes like printing and lamination of Polyethylene film.
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