Converting Magazine

Eldridge M. Mount

Substrate secrets
October 15, 2007

Welcome to the Substrate Secrets Blog.  We will be focusing on the secrets of the various substrates, for like a cat, substrates have three names.  The cats three names are one, the name its mother gave it, two the name its friends call it and third its secret name only it knows.  With substrates, their first name is the trade names and product names such as Melinex 850,  MET-HB, while the second name is the film class, such as, cast polypropylene, oriented polyester, biaxially oriented polypropylene or barrier cast film.  These are the names by which we will know them and how they are called.  But the substrates have a deeper hidden name where the real information about the substrate lies. 

Take the barrier cast film example, what does this name really tell us?  Not much what we really want to know is the secret name of the film which will reveal its true identity, such as a seven layer  coextruded film with a nylon EVOH Nylon core and polyolefin skin layers.  While this is incomplete it permits us to establish the approximate structure for the 7 layer film as:

Polyolefin/tie layer/nylon/EVOH/nylon/tie/layer/polyolefin

But this name is still incomplete, because we don’t know the polyolefins used for the surface, are they the same?  Are they different?  Do they contain additives to help with packaging machine performance? Is it an oriented film for heat shrinking or is it dimensionally stable?  So many questions

These are the types of questions we will be looking at in this Blog, as well as ways to determine the answer to the questions and what substrate technologies can be used to improve their performance or technologies to modify their properties, such as coating, metalizing or laminating etc.  In short we will be on a search to discover the hidden name that the substrate calls itself.

Posted by Eldridge M. Mount on October 15, 2007 | Comments (0)