Matrix Channel Width Calibration for Matte Co-Extruded Film Converting
Calibrating matrix channel width to rule thickness plus 1.6 times composite caliper prevents matte skin fracture on co-extruded film laminated paperboard.
Polyolefin Skin Layer
Functional Barrier
Protective application of polyethylene or polypropylene onto a paper or film substrate provides resistance to moisture and grease. In the packaging industry, a polyolefin skin layer is often applied through extrusion coating to create a heat sealable surface for bags and cartons. This layer prevents the contents of the package from leaking and protects the underlying fibers from environmental damage.
Material Properties
The polymer is melted and spread across the moving web of paper or board to form a continuous and pinhole free film. Because it is chemically inert, it is safe for direct contact with food products and does not affect the flavor or aroma of the contents. The thickness of the layer is measured in microns and is chosen based on the required barrier performance.
It also adds a level of gloss and durability to the exterior of the package. Some formulations are designed to be easily removed during the recycling process to recover the high quality cellulose fibers underneath.
Bonding Capability
This surface allows for the use of hot melt adhesives or ultrasonic welding during the final assembly of the container. It is a fundamental component of liquid packaging board used for milk and juice.