Preserving Receipts?!

[Texas Fire]

Hello everyone! First, I didn't really know where to put this topic. I figured it would go here or possibly off topic, but eh, idk. Anywho, I was wondering if anyone knew of a good way to preserve receipts? By that, I mean keeping the ink on them from fading out over time. Anything and everything gaming related, I hold on to the receipt for each item. However it's safe to say that some have faded over the decades. Any ideas on how to prevent this? I keep mine in a dark area, free from moisture or anything...Still no luck on soooooome...
Thanks guys!

TF