[winstonbike]

I need to determine if paper used in certain packaging is metallized paper (versus a nonmetal shiny paint/print).  I have been out of chemistry a long time, but can I put something on a sample and determine from the reaction whether it has metal particles?

Thanks

Mike

[jeffrey.struss]

Is the metalized paper conductive? I would think it is atleast moderately so. If it is and the fake is not. That is an easy test.

[winstonbike]

Great idea - would I need a certain tester?  I am going to pick something basic up at the hardware store and see where I go from there.

[jeffrey.struss]

Simple digital multimeter should work. If you have a harbor freight tools near by, they usually have a cheapie one for $2-5. You don't need fluke accuracy. Set it to resistance (ohms) and see if there is continuity (some more expensive DMMs have a general continuity beep tester, where it will beep when it detects continuity).

[winstonbike]

Didn't work.  Even the sample of metallized paper I have gets me nothing.  I suspect the problem is the aluminum and the lacquer layer.

Metallized paper is a multistep/multilayer process that is typically as follows:

1.  paper substrate

2.  thin varnish layer to prepare surface for metallization

3.  aluminum vacuum metallization layer of 0.08 to 0.1 g/m2

4.  Thin lacquer layer

Any other thoughts on tests?  Essentially I want to test for the presence of aluminum.

Thanks

[jeffrey.struss]

Can you destructively test samples? If so then remove the laquer layer using steel wool or say paint thinner. The problem though being is the aluminum layer is highly fragile. Honestly, I think steel wool would work best. Grind away a bit of the laquer, should expose the metal in parts and you should be able to test that way. Unfortunately, there aren't many ways to test this without really expensive equipment (atleast not off the top of my head). Additionally, most test are going to be duped if the paint uses flakes of aluminum in the material.

[Zerm]

I like the idea of using solvents to take off the lacquer as that should leave a deposited aluminium layer intact for conductivity testing. 

Alternatively, if you wanted to perform a chemical test, you could burn the paper which would convert the aluminium layer into aluminium oxide.  Then you leach the ashes with hydrochloric acid converting the aluminium oxide into soluble aluminium chloride while leaving most of the soot behind.  After filtering and boiling off the liquid, you should be left with mostly aluminium chloride salt (if there is in fact an aluminium layer).  I'm not really sure where you would go from there but at least that gets you to a concentrated form and removes all the other garbage.  This assumes that you have a large quantity of the paper you can burn though.