I would also hear an expert on this but, I doubt it will ever get hot enough in there to currying ink or even gel it up.
Thank you for all the information! This was exactly the answer I was looking forHow hot is it?
I believe it is better that some materials, like some emulsion, are kept in cooler places.
If you use plastisol inks, while it won't "dry", some brands hardens more than the others. I live in a temperate climate though. Plastisol hardens a little bit(like some gel) around the outside lip of the container but most are easy to clean off before or when you open the lid. These "gel" can still be mixed but they sometimes get into the ink sort of contaminating them and this require cleaning.
And on plastisol not hardening, I got some plastisols which were kept away even from indirect sunlight and the inner part did harden within 3 or 4 months storage. You can still scrape or chisel off the "hardened" plastisol and mix them but they're pretty hard to scrape or chisel off such that I gave up after half an hour recovering probably less than 20% of the "hardened" plastisol.