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For the Love of Phthalocyanine

Those of us who remember September 11, 2001 can never forget the intense blue skies of that infamous morning. InSide the Back Mountain and beyond, that September sky was so clear, so deep blue, it seemed to reach into forever. Then, in a matter of an hour or so, the pain of 9/11 gouged its way deep into our hearts and souls. My artist’s eye remembers those skies as even more deep blue, cloud free, clear and intense, especially after all airplanes were grounded and jet trails disappeared.

To paint those skies in oil, acrylic, or watercolor, we would have had to use plenty of Thalo pigment. Phthalo or Thalo is an abbreviated name for phthalocyanine, a family of blue and green synthetic pigments based on variants of copper phthalocyanine, a deep blue compound used for automotive parts, printing inks, and blue/cyan dyes for textiles, writing paper, toilet paper, paper towels, and even toothpaste colorant. Phthalocyanine was first marketed as a pigment in 1935 under the name Monastral Blue, a name still used by some manufacturers. In artists’ pigments, it's known as a powerful pigment with a strong personality. Thalo is a strong deep blue which visually outweighs the more subdued blues such as Cobalt, Cerulean, Manganese, or even dark Ultramarine.

When I created the three paintings featured this month, I used four blue acrylic pigments in each of the skies: Thalo Blue, Ultramarine Blue, Cerulean Blue and Light Blue Permanent. Ultramarine is a blue toward purple. Cerulean is similar to Thalo but much lighter and weaker. Light Blue Permanent is a gentle blue with a lot of white added in its factory production which eases blending and mixing for the artist. Each sky has four or more layers of paint, each one laid on after the previous layer was completely dry. The horizons closer to the ground are much lighter, while the zenith of each sky is much deeper, darker, and more clear.

Some of my artist friends refuse to use Thalo Blue because it's so strong, staining, and possibly overpowering, but that's exactly why I LOVE THALO! I tend to use it a great deal in skies, shadows, deep green for foliage and reflections in water. Because it is a blue-green on the color wheel, its complement is red-orange, and the two mixed together make an incredible chromatic dark (instead of black) which I love to use for accents in a strong landscape. In all three of these paintings, I mixed Thalo with other blues, greens, and, yes, red and orange to achieve the various shades of deep September greens.

Since water, which is colorless, gets its “color” from what is above it, under it, around it, or in it (such as mud!) I used the same blues to paint the water in each composition that I used in each corresponding sky. Then I painted the reflections of the overhanging trees, knotweed, and mountains. The most fun of all was putting the “life” into each painting. In “The Orange Tree,” the paddlers create the “V” of disturbed current, and the light, bright yellow around the bend creates a compositional arrow pointing straight at the perpetrators! In “The Heron,” the highlights of whitewater in the distance suggest excitement ahead while the backlighting through the large tree on the left marks the time as later afternoon. The painting “River Wall” depicts the dirt bank carved by previous high water. The paddlers have just emerged into sunshine from the dark shadows where deeper water flowed, that darkness obscuring the edge between earth and water.

The color blue has a 6,000 year old history in the world of art, and is known as the color most favored by both men and women. Although Picasso had his famous somber blue period, his choice wasn't Thalo, which had not yet been invented. The same is true for the popular Post-Impressionist Van Gogh and the well-known Impressionist Berthe Morisot, both famous for their use of blues. However, the Thalo colors figure prominently in the work of modern artists like Kandinsky, Lichtenstein, Pollock, and Rothko.

Blue is the rarest of colors in the plant, mineral, and animal kingdoms in nature. Blue gemstones stones…blue butterflies… blue flowers…blue frogs…there aren't as many as there are in other colors. In the non-verbal world of art, blue symbolizes calmness, tranquility, trust, dependability and reliability. What’s your favorite variation of the color blue? I cheer for them all, but I truly love Phthalocyanine!


This article originally appeared in the September 2023 publication of InSide the Back Mountain.

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