Interesting. I detect specification conflicts.
I do know that any film containing a foil layer (i.e.: Capri/Sun) cannot be transparent in any way, as is the TCBG package. A foil layer, however thin, completely blocks light. RF sputtered metallization, at the atomic thickness level, will permit some light transmission, but this would transmit laser energy too, defeating the purpose of the mirror. Ain't no way sputtering can be afforded here, anyway.
Also, I can't see where the alternative method of selective foil placement during film creation is economically possible for this budget-conscious product. I can see where a discrete foil triangle might be inserted at the rip-it score line during final pouch closure, prior to laser perforation, probably by the Volpak. This would answer my main technical curiosity of how TCBG laser scores without puncturing the hermetic package. I will have to wait for someone on SI to give a tech analysis of the score line, or I will need to see a package and do some amateur-grade checking of my own.
Basically, I believe the film spec from Combibloc is different from TCBG's spec. Also, the different spec published by Packaging Digest is also incorrect. Did I mention I suspect the whole world may be incorrect on this one? Sorry, I'm prone to tangents, sometimes.
Besides, the very high tech Combibloc 7 or 8 layer film which is described contains a paperboard layer, which is reaching as far as any potential TCBG application goes.
As I understand it, TCBG is not using foil to protect the product from oxygen degradation. TCBG is, as I understand it, using a very simple and cheap 2 layer film consisting of a primary polyester layer and a very thin LD polyethylene layer to allow the package to be welded. If the selected polyester resin is something like Amosorb 3000 copolyester from Amoco Chemicals in Chicago (Chicago??? Now where's TCBG located again???), it would provide an oxygen-scavenger function for the protection. By specification, it offers oxygen protection equivalent (Amoco claims 'better' but I don't believe them, either) to glass and metal, and is rated for tomato and fruit juices and more.
Naw, I'm not even going to believe my 'foil insert' suggestion, as it's just a major cost adder (and I haven't heard anybody on SI remark about it yet). TCBG is depending on film thickness and laser focal-length defocusing to prevent cutting through the package. Just my humble guess. I'm not well enough versed on film packaging technology to know. But I will figure it out.
Shoe. |
