I use 'unfold' as meaning 'emerge' or 'come into existence'. Here I want to emphasize the PROCESS leading to the emergence of ironic implicature in conversation. I have met things like 'as conversation unfolds' (meaning 'in the process of/during the conversation') in technical writing. This is the structure I was trying to adopt in my original sentence.
Okay, trying to ignore everything else (what is "implicature," anyway?) and just concentrating on these two phrases:
as ironic conversation develops/as an ironic conversation develops?
I would interpret the phrase with "an" to mean a specific conversation between two people. The phrase without "an" suggests the possibility of overlapping conversations, or convers