Do you or don’t you? Does an acrylic painting need to be varnished? Judging from the calls and comments that we get on a daily basis, most artists think not. And those that think ‘yes’ are confused about the best technique or timing for varnishing. Since varnishing questions repeatedly come up as number one on our hit-parade of technical topics, it’s time to clear up a few misconceptions. Why varnish? It makes sense why most artists don’t varnish their acrylic paintings. After all, the surface dries quickly to a durable surface. It’s flexible. It can be wiped clean. So, acrylics don’t need that extra protection like oil paintings, right? Wrong.
While it’s true that acrylics dry fast to a durable and flexible film, there a number of compelling and irresistible reasons for varnishing. First and foremost is that acrylic paint films, even when fully dry, remain porous. This means that any cigarette smoke, atmospheric pollution, grubby fingerprints, and everyday dirt and dust that comes in contact with your painting surface is subject to becoming part of the paint film. While it may not seem like much over a week or a month, the accumulation of grime within the paint film adds up over the course of years. Varnishing is one way to thwart the build up of that environmental grime. Here are some other great reasons to varnish: • Protection against surface abrasion during shipping or exhibition • Boost the brightness and color saturation • Adjust and unify the surface sheen to gloss, matte or semi-gloss. • Protect colors from ultraviolet light. Any varnish will afford some protection but those with UV inhibitors offer extended protection from color fading. • Allow for easy cleaning without fear of removing the paint film What Varnish? For acrylics, varnishes fit within a variety of categories. The first consideration is flexibility. Flexible Varnishes will not crack as the painting surface expands and contracts with temperature and humidity changes. They can be used on all surfaces, such as canvas, paper and wood. Rigid Varnishes are harder and therefore can be used only on inflexible supports like wood panel. They are more durable and provide greater protection against abrasion. They’re great for sealing craft projects on wood like decoupage where surface durability is required. The second consideration is removability or permanence. Listed below is the lowdown on Permanent varnishes for acrylics. They are: • Water-resistant • clear, non-tacky, flexible with a hard surface that resists dirt retention when dry • Non-yellowing, with good UV resistance • Breathable, allowing moisture to pass through • Non-sealing, and unsuited for exterior applications, and; • They are Not removable Liquitex produces four Permanent Varnishes: 1. Gloss Medium & Varnish – Flexible Surface 2. Matte Varnish - Flexible Surface 3. High Gloss Varnish – Rigid Surface 4. Satin Varnish – Rigid Surface Removable Varnishes are generally preferred by conservators because of their, well, removability. Why? Because -- at some point down the road, once your painting has achieved museum status -- there may come a time to roll your artwork into the conservation shop and give it a tune-up for the ages. If the varnish is removable, the conservation-types can strip the painting completely clean, and ‘get under the hood’ to work directly and safely on the paint film. Liquitex produces two conservation-grade, removable varnishes: 1. Soluvar Gloss Varnish 2. Soluvar Matte Varnish Below is a list of what you can expect from the Soluvar twins. They are: • Removable with mineral spirits or turpentine to allow cleaning of the surface without damaging the paint. Once the surface is clean, a new coat of varnish may be applied. • Suited for use on acrylic and oil paintings, both • Made from of a solution of acrylic dissolved in mineral spirits. Other Liquitex varnishes, mediums and paints are an emulsion of acrylic suspended in water. • Suited for thinning up to 25% with mineral spirits (not "Odorless") or turpentine • Clear, non-tacky, water resistant, flexible, "non-breathable" when dry. The dry film is resistant to dirt and prevents water from penetrating the paint surface • Suited for use as a Sealer varnish, and ideal for outdoor use • Self-leveling, and do not hold brushstrokes • Non-yellowing over time • Non-fogging in application or in high humidity conditions • Formulated with ultraviolet light inhibitors that help prevent fading • Formulated to reduce the surface "tack" and pressure sensitivity of acrylic paintings that occur in hot, humid weather • Formulated to reduce the static electric charge that acrylic paintings can build up in cold weather • Ideal for murals (indoor and outdoor) and public access installation, where there is industrial pollution, cigarette smoke, dirt or chance of vandalism NOTE: Soluvar Matte Varnish must be stirred before use to make certain that the matting agent is adequately dispersed. How Varnish? Working with any brand of water emulsion varnish (this excludes Soluvar) can be tricky, which is why, on the label, you’ll read: "When varnish begins to dry do not continue brushing or cloudiness will result." The cloudiness comes from microbubbles that are introduced into the varnish film when working or brushing the varnish layer too long. Those bubbles dry within the film and show up as fog over dark colors. All water emulsion products are prone to microbubbles if overworked. Which is why so many questions come in on our technical help line about varnishing, and why writing this is a good investment for us, and reading it will be for you, too. Here’s the lowdown perfect varnishing technique: Point number one… the surface must be completely dry and cured. That means for acrylic color - three days drying time. Oil colors require six months to one year. The thickness of application will determine exact length of time needed for drying. Also, remember that your environment should be clean, and free of dirt and dust. Brush or Pad Application Brush Application: Use a 1"- 4" flat wide, soft, tightly packed, varnishing brush. Keep it clean and use it only for varnishing. Paint Pad Application: Use a Shur-Line 9" Pad Painter for a brush stroke free look. Vacuum the pad well prior to use to remove lint, wash under water and dry. Pour varnish into a roller pan or cookie sheet lined with foil. Saturate pad and begin. 1. Apply in 1-3 thin coats, rather than 1 thick coat. A thick coat will take longer to dry, may dry cloudy, drip or sag during application and has a greater chance of showing brush strokes when dry. 2. Place the work to be varnished flat on a table - do not varnish vertically. 3. Thinned varnish is more susceptible to producing bubbles. Do not be vigorous in your application. 4. Apply in long even strokes to cover the surface top to bottom while moving from one side to the other. While working, inspect the varnish layer at all angles for bubbles.Even them out immediately. 5. Once you leave an area, do not go back over areas that you have done. If you do, you risk dragging partially dry resin into wet, which will dry cloudy over dark colors. If any areas were missed, allow to dry completely and re-varnish. 6. After varnishing, we recommend that the surface should be shielded from dust with a protective plastic film "tent". When applying Liquitex Matte or Satin Varnish, apply no more than 1-2 thin coats as thick applications may result in cloudiness when dry. If more than 2 coats are desired, first varnish with Gloss Medium & Varnish to desired thickness and apply Matte or Satin Varnish as the last coat. When using SOLUVAR 1. Apply 1-2 layers of Gloss Medium & Varnish as an isolation barrier before applying. Let dry 1-3 hours between coats. Allow to dry 48 hours after final coat. 2. Clean the surface with a lint free rag dampened with mineral spirits. 3. Apply 1-2 layers of Soluvar Varnish. Allow 24 hours drying time between coats |