“What is Gouache?” Gouache is pronounced “goo wash” and rhymes with squash.
True Art Story
The first time I heard the word ‘gouache’ mispronounced was by a student reading from her notes. Her teacher recommended she get a tube of white wash. Back then, I was a new employee at The Paint Spot. I searched the shelves and then ask my coworkers what it was. Most of us could only recall ‘white wash’ from back in Tom Sawyer’s fence painting days. After deducing this was for a watercolour class, I realized that white wash sounded just like white gouache when said out loud. The customer and I bonded over the hilarious similarity of the two phrases.
Since then, I’ve sold a lot of white gouache to watercolourists. White gouache has many uses: it is good for adding back white highlights; it can be spritzed over a dark areas to create stars or snow. Gouache also comes in a wide range of colours. Design students may seek a primary-colour mixing set for their classes. But compared to other water-based paints, gouache seems to have remained overlooked. Not so now. There is a trend a-brewing as more artists discover the potential of this medium for mixed media, plein-air, illustration, and figurative works.
Gouache is not a new medium. It has been around for a very long time. Albrecht Durer and Henri Matisse used gouache to create some of their most recognizable works.
All paints are made using coloured pigment mixed with a binding medium. The medium is used to help the paint hold together and adhere to a surface. To make gouache paints, pigments are mixed with gum arabic, a type of plant-derived sap, natural thickening agent, and binder that helps hold ingredients together. You can think of it as an edible ‘glue.’ It is often found in foods like candies, ice cream, and soft drinks as well as herbal medicines, pills and lozenges, stamps and envelopes; body creams and cosmetics. Gum arabic is an all-natural medium ideal for artists seeking organic and natural paint alternatives.
Speaking of safe – there is no need for solvents with gouache. Gum arabic is also used as a binder for watercolours inks, photography and printing materials. It is a water-soluble, which means it can be thinned with water and it is resoluble with water. Paints made with gum arabic may be squeezed out onto a palette to be used wet, then left to dry and used again by reworking with a wet brush. There is no wasted paint; just add more water and use the paint again.
Gouache is workable and reworkable unlike any other paint. Because it is water-soluble, a wet brush can go back to soften edges or lift colour even after the paint dries .
It is important to note that new layers reactivate previous layers of paint. To avoid overworking, leave half-dry passages alone! Let them get really dry before you add another stroke. Think before you lay down a stroke; commit to it and leave it. Paint the large, wet areas first, and use drier and drier paint as you build details.
I discovered the unique combination of Holbein Mat Acrylics and Holbein Artist Gouache. I painted expressive backgrounds using three colours of the Mat Acrylic then used gouache on top of them. The acrylic was waterproof and provided a permanent and colourful base. Painting the gouache on top of acrylic presented infinite possibilities for moving and blending and even lifting and correcting colours. The acrylic surface held up much better than paper alone would have. My underpainting could be retrieved, and I avoided overworking the painting.
Colour blending was so much easier for portrait work. The paint dried quickly but could be reworked: colours could be re-blended; edges could be softened; shapes could be removed; and yet highlights could be painted back in again.
The pigments used for making gouache are more coarsely ground than for watercolour. The larger particle size of pigments makes gouache very different from watercolour in opacity, matte finish, tooth, thickness, and drying time.
Let’s look at each more closely.
Opacity means that the colour is not see-through and therefore said to have covering power. In student-quality paint, opacity may come from white pigment or fillers but in artist-quality gouache like Holbein Gouache and Schmincke Calligraphy Gouache it is all pigment.
Did we learned the definitions of transparent, opaque, semi-opaque, and translucent in primary school? Here is a quick way to teach it, visit this resource.
Transparency can be used to great effect to create glazes in other paints. A glaze is a diluted layer of colour that allows the white of the paper or a previous painted area to show through. However, it takes discipline and planning to use transparent colour effectively. Create too many layers or use wrong colours, and the art may end up looking overworked and muddy. Here is a link to a Transparent Watercolour Project from our growing resource of projects for school teachers on our website.
If you have relied on transparent washes in the past, it can take a little adjustment to work opaquely. The opaque paint will cover up the underdrawing but is also allows the artist to paint on top of painted or printed areas to make corrections or create new shapes without a ghost of the previous image appearing from underneath. Gouache is an ideal option for collage artists or visual journalists creating images on coloured or decorative papers.
Calligraphers like using it for lettering especially over coloured or dark papers where traditional inks or watercolour may be too transparent. See our November Class
Transparent colours like watercolours and many acrylic inks will appear invisible on black papers. Gouache glows on dark surfaces, even when painted thinly. Highlights and bright colours can be layered and it is easy to build forms in a chiaroscuro method.
The image below was painted using Holbein Gouache on the new Stonehenge Aqua Coldpress Black Watercolour paper. It is a unique, dramatic look for a water-media painting. This step-by-step image illustrates that gouache may be used effectively with watercolour masking fluid.
The rise of resins and pouring mediums have made high gloss acrylics fashionable. But if you have tried to photograph your work, you probably found the glare of the highlights makes it tricky to photograph. Matte paintings may be photographed easily for digital printing and social media sharing.
Gouache is very matte, non-shiny, and non-reflective. The surface of dry paint looks almost velvety to the touch. Darks have a mysterious depth and seem to absorb the light and draw the viewer in. Bright colours look almost luxurious. Ultra-matte may become the new vogue.
Warning: the matte surface is fragile and may be easily marred. It is best to paint in a hardbound book of heavier paper like Stillman and Birn or a watercolour sketchbook like Handmade Books. If you work on loose sheets choose the new PAINT ON series from Clairefontaine. To protect your work use plastic sleeves or cardboard portfolios. If water splashes on a finished painting just let it dry. The damage will hardly be noticeable and require only minor touching up.This is a better alternative to mopping up the water and then repainting large areas.
A matte surface has another desirous advantage. It has tooth. That means it has a texture able to grab a drawing material like pastel, Conte or paint pen. Once dry, it will not permanently gum up markers or pens. If gouache does transfer to the pen tip simply wipe it off by drawing on another piece of paper until it is clean.
Gouache has a seductive paint thickness. It feels more viscous than watercolour, and it has a velvety paint body. The paint self-levels and brush strokes disappear. Are you looking to paint a solid area of one colour? Gouache will do it quickly, smoothly, and evenly. Gouache may be diluted with water, watercolour medium, or more gum arabic to to increase its easy application with all the control your brush and coordination will allow. Do not dilute too much you will miss the advantages of this paint.
Gouache is an excellent option for visual journalists, travel painters, and urban sketchers. Due to the ratio of pigment to binder the paint is less wet than watercolour to start with and you use less water while you paint (usually just enough to move the colour but not too much to reduce opacity). Unlike inks, markers, and watercolour, gouache will not seep through pages. It will not overly wrinkle your pages either.
Gouache is thick and dries quickly; this sounds like a paradox but is absolutely true. The paper dries fast and you spend less time waiting to add the next layer or to turn the page to make a new painting. Unlike acrylic which has a slight tack even when dry, gouache will not stick to itself when you close the pages of your travel journal.
If you want to keep the paint wet while you are working with it, a StaWet Handy Palette is excellent for both studio and plein air painting. Squeeze the paint onto the damp palette paper. Spritz it with water.
On a hot, dry day your painting may dry instantly. Shade the painting and palette with an umbrella and mist with diffuser or choose to work in wet climates like the west coast (or the new rainy wet Alberta).
Gouache may dry more slowly when painted on a primed surface or an acrylic underpainting. Absorbency will be reduced, slowing the drying time and allowing colours to be lifted easily for corrections or special effects.
Colours Shift When Dry
Acrylics appear darker when they dry. Watercolours dry a shade lighter. Gouache also changes value when it dries. Darks tend to lighten and light values tend to darken. This is only a problem for big, flat areas or swatches. In that case, mix plenty of paint when you cover an area that needs to be flat. If you practice enough, you get used to it, and it becomes second nature. With the rewettable nature of gouache you can work in the new colour to more closely match or manipulate the old colour. This little trick will help when creating colour theory swatches.
Speaking of colours there are almost too many vivid colours to choose from. Be careful – too many colours on the palette lead to troubles with middle-value-mud and disharmony. You can paint almost anything with six colours or fewer. We suggest enjoying the adventure by picking primaries different than you’re accustomed to. I was working on portraits so I chose three colours I had never worked with – Chinese Orange, Naples Yellow, and Prussian Blue (plus white) and painted pictures with those colours and no others. These are barely primary but for portraits they turned out to be good choices. Want to know more about colour theory? The Paint Spot runs comprehensive colour theory classes twice a year. Contact us to get your name on the interest list.
Care of Brushes
Wash brushes with warm soapy water and lay them flat to dry. Gouache will wash out of a brush even after it is dry for a long time. We recommend synthetic watercolour brushes.
Kim Fjordbotten (August 2019) As owner of The Paint Spot, Kim Fjordbotten is passionate about helping artists use materials and make art. She is available as a speaker and educator for teachers and art associations. The Paint Spot offers exhibitions, workshops, and beautiful art materials to inspire your creativity.
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