Previous faceup left stains. How do I prevent in the future?

New faceup artist here. I've been painting my own Dollfie Dream heads recently. Specifically, one DDH-09 head that I have wiped. I haven't gotten back to painting it though as I am now in the long and torturous process of stain removal, as the previous faceup stained it! I couldn't find any other discussions of this happening, so I have no idea how other faceup artists prevent this or deal with it.

Before painting I sprayed two coats of Zoukei Mura finishing powder, leaving 15 minutes between each coat. I then waited about an hour or so before I went into painting it. I used Liquitex Acrylic Paint that I had thinned down with water, and I manage to paint one layer before I had to put it off for a while. I did not seal it before putting it off. When I was able to come back to it, I decided I could do better and wiped my work. And that was when I encountered staining in place of where painted on eyelashes and brows used to be.

Were my base coats too thin? Should I have used medium to thin my paints instead? Or perhaps the humidity in the air caused the unsealed layer of paints to soak through my base coats?

I dare not paint nor buy any more heads until I find answers, and I have one body in desperate need of a head, so I really want to know what I did wrong. Please share with me your process and materials if you don't have this problem!

I don't have much advice to give as I’m pretty much new to the vinyl side of the doll hobby. However, I have painted DD heads and I’ve also run into issues with staining.

Certain pigments will seep right through the sealant no matter what. I’ve had almost 6-7 layers of sealant on a head, and this specific type of paint managed to stain it pretty bad.

I do let the sealant layers take more time to cure so it’s guaranteed to be solid by the time I’m handling the head. My base layers are at least 3 coats thick, and I leave it overnight to dry. For my in between layers I wait 30 minutes before painting/blushing. 

FWIW I also use ZM Powder Finish and the only staining issues I’ve run into are that paint and a Caran d’Ache Watercolor pencil in Burnt Sienna.

Edited September 2, 2020 by engelinvitro

@engelinvitro

Thank you so much, I'll keep what you've said about the extra layers and cure time in mind! Sienna does seem to be a particularly strong pigment—that was what stained my head. I'm just relieved I don't have to drop ZM Powder because I really like the smoother results.