How to Protect Natural Colors
I have been painting with natural colors for several years. Throughout these years, fugitive colors like those derived from saffron, hibiscus, safflowers and other wildflower and plants have been my favorite part of the work. So, the question of preserving natural fugitive colors has always been on my mind. I have also noticed that this is a common question for a majority of natural colors lovers.
For a while, my protection system was synthetic UV sprays that provided up to 90% protection to the colors. However, for long time I wanted to change the sprays with a substitute solution that used natural materials instead.
My findings, which I am happy to share below, are based on testings conducted over the last couple of years. Even though the protection results are not the same as when synthetic solutions are used, I am glad to say it has a very similar result. With just a couple of more additional steps, as seen below, your art pieces can be protected.
Please note that this is an ongoing and open subject that all natural color painters and lovers should contribute as it is an important subject.
Before applying the following process, please do a small preliminary test on the all colors and materials used in your artwork. After making sure that there are no changes to the colors or damages caused, then apply to the actual piece. Since these are all natural elements, results will vary depending on the natural resources you use to create colors.
Red Raspberry Seed Oil (Optional)
or Carrot Seed Oil (Optional)
What is Shellac:
Shellac is a versatile, non-toxic natural resin that is secreted by the female lac bug (Kerria lacca). These insects are found in the forests of India and Thailand. Shellac is usually scraped from a tree’s bark where the female lac bug creates tunnel-like tubes as it goes across the branches of the tree.
There are many colors of shellac. It typically comes in warm colors ranging from a very light blonde ("platina") to a very dark brown ("garnet"), with many varieties of browns, yellows, oranges, and reds in between. The color is determined by the sap of the tree where the lac bug lives as well as by the time of harvest. I tend to use platina (light blonde) colored shellac.
Shellac is processed and sold as dry flakes. It can also be dissolved in alcohol to make liquid shellac, which is can be used as a brush-on colorant, food glaze, or wood finish. The thickness or concentration of shellac is measured by the unit "pound cut." This refers to the amount of shellac flakes, in pounds, that is dissolved in a gallon of denatured alcohol.
Please note that shellac naturally contains a small amount of wax (3%–5% by volume) that comes from the lac bug. In some preparations, this wax is removed which results in "dewaxed shellac". This type of shellac is used in situations where the shellac will be coated with something else, such as paint or varnish, so the topcoat will adhere. Waxy, non-dewaxed, shellac has a milky appearance when liquid but dries clear.
I use premium dewaxed blonde shellac flakes as I usually need to cover them with oils.
Additional materials needed:
Scale or measuring cups
Premium Dewaxed Blonde Shellac (can be found online or in hardwood stores)
Denatured Alcohol (can be found in hardwood or paint stores or online)
Mortar and Pestle
I use the ration of 1: 9 or 1.5: 8
I suggest 1:9 for starting and later you can adjust.
This means that for 1 Ounce of Shellac flake (28.3 gram or 2 Tablespoons) I use 9 Ounces of Denatured Alcohol (0.26 liter or 266 Milliliter or 1.10 Cup or 18 Tablespoons)
Or for 1.5 Ounce of Shellac flake (42 grams or 3 tablespoons) I use 8 ounces of Denatured Alcohol ( 0.23 liter, 230 Milliliter, or 0.8 cup or 16 Tablespoons)
1. Grind the flakes to a powder
2. Add it to glass jar
3. Measure your Denature Alcohol based on the ratio given above, then add it to the flake powder and shake
4.-Leave the mixture to sit for 24 hours. You can occasionally shake the mixture during this time
5. The mixture is ready once your liquid has light orange colors
6.- Shake the mixture before use. There shouldn’t be any unmixed powder.
IMPORTANT NOTE: before applying to your art, I suggest you do a test sheet with the colors used to make sure it won’t damage your piece. Even though shellac is not supposed to interact with other natural colors, it is much safer to test before adding it to your entire piece.
7.- Use a large brush to apply your first layer to completely dried color
8.- Wait a couple hours for the layer to dry (can take up to 24 hours). Repeat process to apply a total of three layers.
9.- This step is optional. Adding Red Raspberry or Carrot Seeds Oil will improve the coverage. However, it may add a little tint to colors or white areas. Test it before adding it. If decide to avoid it, you can add extra layer of shellac instead.
To add the Raspberry Seed Oil:
After all layers dry, add a thin coat of Red Raspberry Seed Oil or Carrot Seed Oil (I prefer Red Raspberry since has higher coverage). Before this step, make sure that the shellac was properly coated all throughout so the oil won’t leak onto your paper.
11- After everything dries, cover your painting with a UV protected glass frame.
12- Please note that any artwork including natural colors should NOT be placed in front of the direct sunlight.
Examples of process:
These experiments were done with Saffron, Safflower and Hibiscus ink with Shellac, Dammar, Carrol Seed Oil on150 lbs watercolor paper. Samples were exposed to direct sunlight for 20 days.