Hi Chris - even I'm not aware of anything that large on a substrate other than aluminum, sorry! You'd never have the tensile strength to survive the printing process at that size, and you'd have huge issues with registration/stretch/etc.
If you do find something that works and is more cost-effective, let me know! We've been looking for years, but even polyester doesn't scale well that large (and has much poorer ink/water balance properties to boot).
Also - don't forget that although Aluminum is a large part of the cost of a plate (especially large plates in high volume), you get a significant portion of that value back in your scrap recycling. All else being equal, you're actually not going to save a lot of money with other substrates once you net out the scrap value. If you're getting less than 80% of the LME value back on your scrap, talk to your Kodak sales rep or dealer and we can put you in touch with our scrap partner for a better deal (we don't take any cut from that, but have negotiated a better group rate for our customers).
Kevin Cazabon / email@example.com
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