I Googled this, but didn't come up with much of use.
Got a project that uses a BUNCH (10,000+) of short pieces of white PVC pipe. Just your regular run-of-the-mill potable water PVC. Problem is there are 2 different sizes, and getting them mixed up is an issue. Should have made one size out of gray PVC electrical conduit---my hindsight is still 20-20.
SO----I want to dye one size a different color. ANY color. Around 4,000 pcs, 2.5" long. Just a dunk and stir, cold process if possible.
What's out there in a permanent, cheap, safe, easy to find and easy to use dye that will color rigid PVC?