In article ,
ss writes:
I am about to paint a wall (emulsion) that has a couple of grease stains
on it, would PVA act as a sealer? The 2 spots of grease are about 4 cm
in diameter.

It might work, but OTOH, if it's sufficiently greasy on the surface
to prevent wetting and some moisture penetration, the PVA might not
stick.

You might also find the emulsion won't stick to the PVA - some won't.

You can get stain sealer, which is probably a better bet. Undercoat
gloss paint used to work very well for this too, but I haven't tried
it since the volatile solvents were largely removed from them.

--
Andrew Gabriel
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