When in doubt, Google it. The technique I learned and like the best is to prime the canvas with Kilz2 Latex Primer. This can be found at most paint, hardware, and home supplies stores. It's commonly used to seal surfaces to keep out water, and to seal in stains to prevent seepage through paint layers. It creates a great surface for alcohol ink painting. Enjoy! Let me know how you like it.
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Thanks to the wonderful alcohol ink artist, Brittainy Bolding, for sharing her secret on this topic in her YouTube video, How to Prep Your Canvas for Alcohol Inks.
Finally I came across one product that protects with a beautiful glossy coat, and doesn't spot my inks at all: Krylon "Short Cuts". Another happy side effect is that this coating enhances the color of the alcohol inks even more!
This product creates a beautiful protective surface, but it doesn't provide UV protection. UV protection is provided by various acrylic sealers, the very ones which spotted my inks. Therefore sealing my paintings is a 2-step process. Once the painting has been sealed with the Krylon Short Cuts, it has an enamel finish to which any UV protective medium can be applied with no problem.
One last word of advice: Dust particles love to get stuck in your paintings when these sealers are drying. A very effective way I've found to minimize this is to create a little cover to place over your painting immediately after spraying, and while it dries. I use two small shoeboxes, with a spare piece of mat board over them. This builds a little "bridge" for the artwork to sit under. It lets air circulate, but most of the dust stays out. Good luck!
Where to Buy:
Both the Krylon and the Golden products are widely available. I buy mine at Joann's, Michael's, or on Amazon.com
I hope this is helpful. I would love to hear your comments on what works for you. Happy painting!
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