Choosing the Right Pigments and Paints
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Choosing the right paints can be tricky because of so much variability across manufacturers. Lightfastness is not the only metric to look at when evaluating paint performance outdoors. Murals challenge paint films with more extreme conditions, many which would rarely be present for an indoor easel painting at a given time. Paint films will often experience high temperatures, exposure to moisture and humidity, moss, bacteria and fungi, while also gradually accumulating carbon monoxide and other chemical pollution in the air. Murals can be exposed to caustic materials, harsh solvents, and purposeful damage, which is why choosing the right pigments also require artists to properly prepare walls, and consolidate thoroughly.
When an artist can document their paint palette, it is important to include the manufacturing date of the paint, the maker, and any pigment information included on the packaging. For situations where the mural must absolutely last, use a reputable brand like Golden Artist Acrylics.
Economical paints often include opacifiers, formaldehyde and other harsh preservatives, and can even include inconsistent paint manufacturing, which can affect the longevity of paint binders.
Muralists will struggle to find a balanced Titanium White that has high tinting strength and is also well manufactured. It might be a surprise to some muralists that the manufacturing process of Titanium Dioxide as a paint pigment varies by source and the differences can dramatically impact the longevity of a mural.
Finding substitutes for Cadmium paints, which were historically thought to be lightfast for outdoor murals, can be a challenging task but not impossible with modern synthetic pigments. Artists will find small variations in temperature, but often the biggest difference is in the opacity of a paint. Depending on your painting style, this can be an advantage or disadvantage.
A reputable paint manufacturer will test the longevity of their pigments by conducting long term exposure tests. These tests are often available online.
SPARC's Recommended Paint Manufacturers
The following list is in order of quality and expense. Yes it is the case that high-purity high-density pigments and quality binders often translate to a higher prices. This also translates to high coverage. Not all heavy body or full bodied paints are equal either. Some economical paints made by Blick or Utrecht contain thickeners and opacifiers that emulate high pigment paints like those made by Golden or Liquitex. If you have the budget capacity and your mural absolutely has to last, choose a reputable paint manufacturer. If you need an economic solution, the paints in this list all perform well. With a MuralShield finish, no matter the paint choice you make, you will have a highly durable mural. A final note on pigments–the second table below lists colors by pigments because while colors may appear similar, not all pigments are suitable for outdoor mural use.
Golden Artist Colors - Used exclusively on SPARC Projects
Golden is the top tier paint manufacturer for murals. Their extensive pigment information and high quality materials make for the most durable murals. This paint is thick and requires extension with gloss medium. A little goes a long way, which despite its high price, once extended is comparable to other studio acrylic brands.
Choose the Heavy Body Paints line. Avoid using Fluid, High Flow or Open paint lines as they contain modifiers that may not be suitable for long term durability.
Choose Gloss Medium (Item #3510) for glazes and extending colors without affecting the paint binder. Do not use mediums that contain UV or UVLS.
Gallon containers are available. Heavy Body Paints are incredibly thick (we often invert whole open gallon containers of their paint to impress onlookers). Mix Heavy Body Paints to create a cream consistency, no more than 1:1. Our process involves scooping pure colors into separate containers to which we add medium to. Mix by hand or shake. Do not use a drill mixer. Aerating paint will cause it to cure prematurely in the container. Aerated paints will have a shorter shelf life when stored.
Liquitex
Choose their Heavy Body Acrylic Paints line. Liquitex is a reputable company with excellent pigments.
For extending and glazing, use Liquitex Gloss Varnish. Do not use mediums that contain UV or UVLS. Large quantities and bulk discounts are available from the manufacturer.
Blick Artist Acrylics
Blick similarly has several lines of paint. Choose "Blick Artists' Paint" which is a heavy bodied paint. Contact the supplier for larger quantities and bulk discounts. This is an economical solution suitable for outdoor murals.
Utrecht Artists' Acrylic Colors
Use Utrecht's heavy body acrylic paints. Similarly, contact the supplier for larger quantities and bulk discounts. This is an economical solution for murals.
Nova Color Paints
This might be controversial because so many muralists have great confidence in Nova Color Paints. Unfortunately the quality of their pigments and binders are questionable. They have unlisted additives and provide little transparency into their manufacturing processes. They have been known to recommend paints and mediums that are not suitable for long term outdoor durability. Their gloss mediums have not performed as well as previous years, which has led to some destructive surprises! Yes their paints come in a decent consistency for mural painting, and they do sell 1 and 5 gallon containers. Again, it all comes down to your budget and the expected durability of your mural. If you are going to choose Nova Color Paints, be sure to choose your colors based on durable pigments. Avoid using their gels and mediums as top coats as they will yellow outdoors.
Behr House Paints (Or any other outdoor paint bought at a home improvement or paint store)
Behr in particular should not be used as a mural paint. While it is amazing how far matched colors have come, and they are on their own durable for painting outdoor structures, the physical process of painting murals sets these paints at a disadvantage. Any water that gets into your paint will affect the durability of that paint film in the short term. This is incredibly difficult to avoid when using brushes. House paints use special chemicals to modify their opacity, consistency, and they self-shed to maintain a clean appearance. These characteristics are not suitable for fine art murals even though you get great coverage. We've all been there–whether it's a large color field or background, or even a dedication panel–try to avoid the temptation!
If your mural was painted with Behr or other house paint brands, you may see a yellow resin surface when applying too much MuralShield in one coat. Paint chemistry is wide and diverse, always test! If you see a transparent yellow dye appear, reduce the amount of MuralShield being sprayed and avoid drips. If spraying, add an extra 2 feet between the tip of the sprayer and the wall and move the wand faster over the surface to "fog coat" the mural.
Additionally, be careful to not mix house paint brands as they can have dangerous or adverse chemical reactions.
Aerosol Paints i.e. Montana, MTN, and Liquitex
Spray Paint is magical and all artist grade spray paints that we have used are compatible with MuralShield. So long as the spray paint lists their pigments, and you can follow the recommended pigments below, your mural will be more resistant to environmental stresses. These paint films are incredibly thin and will not match the performance of acrylic paints, but don't let it stop you from using them.
Spray paint is responsible for incredible advances in murals and ongoing experimentation will only further improve this amazing medium. We have to consider the environment when using spray paints and aerosols. It is a wasteful medium and manufacturers need to be responsible and responsive to the impact their product is having in landfills and ecosystems. If only there was a reusable way of atomizing paint...
Airbrush Paints
Airbrush paints are acrylic paints that have been modified with fluid mediums that can be atomized by air compression. Most of the paint manufacturers listed above also make airbrush equivalents. Thinning mediums can also be used to create your own airbrushing paints. The same information for spray paints apply here. Thin films make for reduced durability. When choosing airbrush acrylics, choose your colors based their pigments.
1 Shot or other Oil Based Paints
We do not recommend using 1 Shot for murals that require durability. These paints excel for sign painting and pinstriping. Advertising companies use oil based paints because of their long dry times that lend themselves to creating fluid blends and techniques that acrylic paints cannot accomplish straight out of the can. Oil based binders do not cure to form a chemically stable polymer. Heat can reactivate oil-based binders even after murals have been outdoors for years after they have been painted. This can create havoc should you need to restore an oil-based mural.
Please note that MuralShield is not designed for use over oil based paints. While it can serve as a UV protectant, the sacrificial coatings used with MuralShield is unable to protect oil based murals from tagging or other forms of vandalism.
SPARC's Recommended Pigment List
Recommended Paint/Pigment | Replacement of... |
Hansa Yellow Opaque | Cadmium Yellow Medium |
Diarylide Yellow | Cadmium Yellow Dark |
Bismuth Vanadate Yellow | Cadmium Yellow Light |
Light Bismuth Yellow | Cadmium Yellow Primrose |
Pyrrole Orange | Vat Orange or Cadmium Orange |
Pyrrole Red | Cadmium Red Medium |
Quinacridone Red | |
Pyrrole Red Light | Cadmium Red Light |
Naphthol Red Medium | |
Quin Magenta | |
Permanent Violet Dark | |
Dioxazine Purple | |
Quinacridone Violet | |
Quinacridone Burnt Orange | |
Phthalo Blue Red Shade | |
Phthalo Blue Green Shade | |
Ultramarine Blue | |
Phthalo Turquois | |
Phthalo Green Blue Shade | |
Jenkins Green | |
Cobalt Teal | |
Chromium Oxide Green | |
Mars Yellow | |
Yellow Oxide | |
Red Oxide | |
Burnt Umber | |
Yellow Ochre | |
Raw Sienna | |
Raw Umber | |
Burnt Sienna | |
Mars Black | |
Titanium White | |
New Suitable Colors for Murals | |
Benzimidazolone Yellow Medium | |
Benzimidazolone Yellow Light | |
Contact
SOCIAL AND PUBLIC ART RESOURCE CENTER
685 Venice Blvd,
Venice, CA 90291
(310) 822-9560
sales@sparcinla.org