All the examples I've seen are chips that are bleeding color anyway. They will transfer color to whatever is next to them, including other chips in a stack . When you see it on a clear plastic holder, it's more obvious. The color does seem to penetrate the plastic filps; mylar windows in cardboard holders don't seem to absorb the color so you don't see it.

Worst bleeders are old red chips, like the one you show, and earlier Chipcos where the color doesn't stick well to the substrate.

I have thousands of chips in 30 pocket pages, some for over 20 years. Except for the fact they fall out when the new, smaller pages tear, I am happy with them.

I agree with David on the plasticizers. PVC is hard and brittle. Manufacturers add plasticizers to make it softer. If you put silver or copper coins in one that has been made pliable, the plasticizer will affect the metal in the coin. That's why coin collectors don't put their coins in the soft ones. They tend to turn green .