Foiling trouble on black pvc coated paper

[mulo_g]

We are binding books for a client with pvc (black) coated cover (purchased by us). We tried silver foiling the logo on cover. Cover is plain semi gloss without any texture. However, the logos approximately 12mm x 12mm patch (reverse) cannot be foiled. It leaves several unfoiled spots. We have used copper plate blocks/dies. Used foils from kurz, Astral. Used letterpress type platen, and pneumatic press without any success. My foiling guy is suspecting covering material since foiling comes ok on paper and bopp laminated paper. Having said so are there any suggestions from anyone since time is limited and we have already bought cover material? Any ways to reduce surface tension of cover with some chemical or primer. Covering material is not corona treated. We already tried aqueous coating. Help will be highly appreciated.

 

[lfelton]

If you’ve tried all the normal things (heat, dwell time, pressure, change foil to suit substrate), then there are a couple of things you can try to get you out of a jam. Assuming you have perfect registration, double hit the covers. This generally works for pin holing. Second suggestion. Hit #1 using a foil that will work. On book covers Kurz Colorit V900 is specifically for book covers and we’ve found it sticks well to most things. Then hit the cover again with the foil you really want. This relies on perfect registration of course, so if you don’t have this, find someone with a Kluge. Final suggestion. You don’t say what kind of covers. Assuming it is embossed and on a 3 part cover, it can be almost impossible to get enough pressure to avoid pin holes if the covers are already made. Your best bet is to foil them before they go on the casemaker that way you can alter the packing (probably epoxy board) so that you can maximise the pressure.

 

[mulo_g]

I will try. The cases are not made yet. And, can you please elaborate on epoxy board? What is it?

 

[mulo_g]

Thanks Ifelton
Another foiling person told me that cylinder foiling machines like converted Heidelberg are more forgiving than flat bed because contact area between die and substrate is less at any given moment. Anyone having this experience?
​​​​​​I am waiting for more foils.

 

[lfelton]

We don't have a cylinder, we have a Kluge EHD, so can't help you on that question. If you have sufficient impression strength and good even heating, I can't really see why using a cylinder would make much difference. Have you tried wiping the cover with alcohol before foiling to eliminate contamination? That's a long shot, my money would be on you needing a foil where the adhesive is matched better to the substrate.

This is epoxy board, AKA glass board:

http://www.foilco.co.uk/products/epoxy-glass-board/

 

[mulo_g]

Ifelton, you are genius. I have now ordered some foils for trials. Meanwhile, I got my job with another foiling person. He successfully did it, though I don't know how. Thanks for guidance.