Here is the Preparation Instructions Coating Solution given in Sigma Aldrich. – prepare a solution containing ~3.4 wt.% PVP and 1.1 wt.% poly(melamine-coformaldehyde) (Catalog Number 418560) in PGMEA solvent (Catalog Number 484431) Semiconductor Solution – prepare a solution consisting of 2 wt.% TIPS-Pentacene (Catalog Number 716006) dissolved in a solvent blend consisting of 91% anisole (Catalog Number 296295) and 9% decane (Catalog Number 457116) by weight.
I have mentioned a few solvents that can be recommended for poly(methyl methacrylate), i.e. PMMA, elsewhere at this forum – please note that anisole is included: https://www.researchgate.net/post/With_PMMA_which_solvent_to_use