What is the best way to achieve a matte finish out of the mold?
Can one use a glossy plug and pull a glossy mold and use a flat/matte semiperm to get the matte look right out of the mold? Or should the glossy plug be matted with the semiperm before the mold is made so the mold has the matted finish?
Anyone have any tricks?
The best way is to have a matted finished mold.
Depends on how much texture you want to have, but a mist coat of PVA works wonderful.
Clearcoat with a Matte or Semigloss automotive clearcoat.
I was hoping to use 2k automotive as an IMC and get the finish right when I pull the part.
Sometimes I wet sand parts with 1200 paper then apply furniture type waxes like beeswax or other. This way any part can be matt or satin with some light hand rubbing regardless of the mould finish.
Hi
I use 2k imc everyday , but my objective is to get gloss Finnish. BUT I use flouro paints , SEM from colour horizons. These Are concentrates that you mix with clear.
If painted just like that you get a dull Finnish , so I clear in mould first , then flouro , then back it up with white and then undercoat so the laminate stick to it.
Although that doesn’t directly help you , I think the process does. My moulds are shinny and with out clear it a little dull/Matt type Finnish.
So I’m sure a Matt black paint , backed up with undercoat would do the job fine.
Only one way to find out 
Maybe try a test on a piece of window glass first to see it it works and from a shinny surface it give you the desired result.
Tim
Matt paint on a shiney mold comes out as gloss
I have used PVA with good results, just run a thin coat with low pressure. If you think about it, you are basically applying a light texture to the mold, which will make the finished part less reflective.
Matt PVA will most likely give you your desired finish. Alternatively scotchbrite the mould. When we require matt parts we simply use a matt mould
Or wetsand the mold with 2000 or 2500