Research into Protective Coatings For Artwork

A final protective coat is so important for the longevity of artworks. There are so many options these days for works on paper, as well as works on canvas, wood, or other surfaces where vulnerable mediums like water-based, chalk-based, mixed media, charcoal, etc have been used.

Choosing your finish is pretty technical … use the wrong one and you may smudge the charcoal or the water-based medium may bleed… a disaster on a piece that was finished and looking beautiful before you applied the protective coat!

I used to work with only acrylic paint, sometimes some spray paint or collage. I had good finishing mediums for those. But these days I’m working in a wide variety of mediums, including more vulnerable ones like watercolour inks, soft pastels, etc, so I’ve been experimenting with these finishes in order to learn their strengths and limitations so I can choose wisely for the final stage of completing the art I’m making these days.

The verdict

Overall Favourite and for dry media that tends to smudge: The satin acrylic spray varnish.

• It’s great for mediums that smudge or bleed if you brush a liquid varnish onto your artwork (think soft pastels, charcoal, watercolours).
• It works well on paper, canvas, or wood panels and most all art mediums.
• It’s easy to apply onto small and medium artworks. It’s trickier on a large artwork because you need to get the movement of your arm right for a smooth finish.
• No messy brush cleanup!
• Be sure to apply it outdoors where you have good ventilation and with a mask, and dispose of your empty can safely.
• Lascaux fixitive is another good alternative, though I find the smell incredibly toxic.

Watercolour artworks: Dorland’s Cold Wax

• I was surprised to find that Dorland’s cold wax can be applied on paper and it doesn’t make the paper greasy or alter the colour of the paper.
• It’s a wonderful sealant for watercolours and other water-based mediums. They won’t smudge or bleed when you rub the cold wax onto it.
• Leaves a lovely soft, smooth sheen.
• Easy to apply.
• Has a nice smell.
• No messy cleanup of brushes required!
• You can also apply Dorlands Cold Wax onto acrylic paintings for a lovely finish.

Works on Paper: Liquitex ultra matt medium

• This is a non-greasy water-based liquid varnish that can be applied on paper without discolouring the paper.
• If you like a matt finish, a thin coat of this will get you a lovely matt finish without altering the colours.
• Doesn’t have a nasty smell.
• Easy cleanup of brushes with water!
• Can also be used as an undercoat to make your surface more absobent – better for inks, watercolours, and soft pastels!
• Be careful to not apply it too thickly or else it will dull your colours.
• Dorland’s Cold Wax and Amsterdam Satin Spray are other good options for works on paper if you prefer a satin finish.

Large acrylic paintings on canvas and wood panels: I really like the Gamvar gloss and Gamvar Satin liquid varnishes for large paintings.

• I like the non-sticky consistency, it’s got a good self-leveling capacity, and it doesn’t tend to easily streak, so you don’t have the pressure to work quickly.
• It doesn’t smell as much as many varnishes do.
• Brush clean-up is relatively easy with Gamsol.
• Dorland’s cold wax is a close second for large acrylic paintings.