Looking for somewhat flexible metallized film

Hi,

Aluminized mylar is pretty common, not sure if it will stretch

Ebay has quite a bit:

cheers, Jamie

Mylar is tough to stretch. We could probably do it somehow but aluminum metallization can develop a fine non-conductive layer quickly and has a pretty bad surface roughness.

You're going to want to use conductive ink for that, not a metal film. The metal will crack into a zillion tiny islands. Good-grade carbon ink will stick to low surface energy substrates such as teflon or polyethylene, and is tough enough to take a hard crease without cracking.

Cheers

Phil Hobbs

That single annometer roughness is pretty tough to meet. But have you looked at the food industry? Like Lay's potato chips come in a pretty thin metallized film.

I don't think that "potato chip film" stretches. ...Jim Thompson

Some does, a little. But they mostly have the same problem as party balloons: Another non-conductive coating to make them shiny or have a "wet" look. It's all about shelf appeal. Buy me, buy me, be hungry, salivate, be hungry, now, must buy, must buy.

Good idea. Do you know where one could buy such material ready-to-go off the shelf? Price is not important unless it's really outlandish, because this is only for a materials test station.

I've looked at carbon nanotube material which could almost get there in terms of surface roughness. But it only existed on glossy print, not on a shelf with a price tag on there.

I don't know who sells it ready-coated, no. It screen-prints very well, though, and as I say is very tough, so you could put it on the balloon side of the film.

Cheers

Phil Hobbs

Isn't metallized mylar used to prevent the helium from escaping, not for the looks?

Does the film have to be metallic or just conductive ? A finnish company called Canatu manufactures carbon nanotube coated films, which might be suitable. Their main substrate is PET, but they might have something more stretchable, too.

No idea but definitely also for looks. There were shiny golden ones and silver ones.

Yes, I'll inquire if our contract company can do this. We just don't want to turn this into another science project.

Only conductive and that doesn't even have to be very good. A few hundred ohms corner to corner would be ok. I also does not matter whether it's translucent or not. But surface roughness is a key parameter. If that is more than very few nanometers the whole testing idea isn't going to work.

Aha, now we are getting somewhere. Thanks!

PET has a Young's modulus of around 2.5 GPa, and elongation at yield of > 15%.

They're really concerned about keeping the chips airtight to get long and consistent shelf life. I did some work for a company that makes the packaging materials years ago.

I am sure they do that as well. But when talking to a packaging designer I was amazed how much effort goes into the glitz factor. IIRC he was a very highly paid guy and had the freedom only real artists are afforded.

Yup. Gas diffusion in metal is many orders of magnitude slower than in plastic.

Cheers

Phil Hobbs

you're looking for a metal that can deforem 5% elastically ? if the matal can;t handle the deformation it'll come off the film.

I've seen metalised PE used in wine bladders. I don't know it if can handle 5% though.

We can go lower than 5% if needed. The main problem is surface roughness which needs to be very few nanometers. We've got a process in-house that can do this but it can't make such large films and it is very labor intense to do that just for a test station.