The Four Viscosities of Acrylic Paint

Heavy Body Acrylic

Golden Heavy Body Acrylic Quinacridone Magenta 59 ml

The most characteristic feature of heavy body acrylic paints is their stiff, buttery consistency. This allows them to hold peaks and retain brush strokes, making them ideal for impasto techniques and painterly brushwork. A palette knife or a stiff hog brush can be used with heavy body acrylics, as they allow you to sculpt the paint and build up layers of rich colour and texture.

In fact, Golden’s first acrylic range, introduced in the 1980s was their heavy body acrylics. Their thick texture appealed to oil painters who were already familiar with a similar consistency. Heavy body acrylics are recommended for artists who enjoy the density of oil paint, but who find the long drying time too restrictive. When painting with acrylics, multiple layers of varying thicknesses can be applied in any order and the next layer can be applied as soon as the last is touch dry, unlike with oil painting, where you need to be mindful of the fat-over-lean principle. This is an advantage for artists who want to build layers of paint quickly.

Heavy body acrylic’s dense consistency and thick paint film allows solids such as marble dust, pumice powder, sand and glass beads to be incorporated. Once dry, the material will be firmly held by the acrylic polymer, adding bulk and texture and bringing a three dimensional aspect into the work.

Golden Heavy Body Acrylic Quinacridone Magenta brushed out beside Golden Open Acrylic Teal.

Of all of the available viscosities, heavy body acrylics generally provide the best coverage. This is due to a thicker paint film, rather than a higher pigment load. Golden’s acrylics vary in terms of sheen and opacity depending on the individual qualities of the pigments used because Golden refrain from adding mattifying or opacifying agents to their paints

Soft Body / Open Acrylic

Golden Open Acrylic Teal 237 ml

Most acrylics dry quickly, giving the artist a relatively short working time. Open Acrylics have been formulated to have a drying time which is up to 10 times longer than traditional acrylic paints. It offers possibilities for techniques which require the paint to stay workable for longer, such as blending and wet-in-wet painting.

Golden Open Acrylics are an example of a soft body paint, although they are slightly more viscous than most other soft body acrylics. Straight out of the tube or jar, they have a creamy consistency and are more self-levelling than their heavy body counterparts. Lower viscosity means that soft body paints are suited to more fluid, continuous brush work. A soft brush will give you the smoothest possible application, but this versatile consistency of acrylic can also be applied with a medium to firm brush, depending on your painting style. The paint will retain brush strokes to a certain degree, but to a lesser extent than heavy body acrylics.

Golden Open Acrylic Teal brushed out beside Golden Fluid Acrylic Chromium Oxide Green and Golden High Flow Acrylic Transparent Red Iron Oxide that has been allowed to run.

Golden Open Acrylic’s extended drying time makes it behave differently to other soft body acrylic paints. As it dries, it becomes increasingly viscous and stiffer, without forming a skin, allowing for more textural handling of the paint. This slow-drying quality is an advantage on the palette, as well as on the canvas. Because it dries quickly, standard acrylic paint can become unusable on the palette, which can be wasteful. Golden Open Acrylics can be kept fresh for far longer, reducing wastage—even as it begins to become tacky, it can be reopened by brushing with water or a medium. It can take more than two weeks for the paint to form an impermeable, immovable film, and once it has reached this stage, it will remain so permanently.

Fluid Acrylic

Golden Fluid Acrylic Chromium Oxide Green 118 ml

There is a common misconception that thicker paints contain more pigment than their fluid counterparts. However, a fluid paint will provide the same depth of colour in a less viscous binder. Fluid acrylics flow consistently from the brush and are self-levelling, reducing the retention of visible brush strokes, especially when used with a soft synthetic brush.

Golden originally made fluid acrylics for artists on a custom basis but their popularity was such that they were soon introduced as a standard line. Golden Fluid Acrylics are available in bottles and have a consistency like heavy cream. They can be poured or dripped onto the surface for vivid puddles of colour, or they can be used for more precise techniques, such as glazing.

Glazing is a technique originally established in oil painting which relies on the inherent transparency of certain pigments. Multiple transparent layers are used to render the subtle complexities of colour, light and tone. This gives the painting depth and realism which are impossible to achieve when using opaque colours. Oil painters know that glazing with oil paint can be a time consuming process because each layer can take a long time to dry. In contrast, acrylic paint generally dries very quickly, allowing you to work at a faster pace, which may be preferable for some artists.

Golden also refrain from using opacifying fillers in their fluid acrylics, so the naturally transparent qualities of certain pigments can be used to full effect. Information regarding transparency for each colour can be found on the tube, on a colour chart, or online.

High Flow Acrylic

Golden High Flow Acrylic Transparent Red Iron Oxide 30 ml

High Flow Acrylic are the most fluid paint in Golden’s range. They are a good example of an acrylic ink and have an aqueous consistency.

Many inks are dye-based, meaning that colour is completely dissolved in the binder to make a solution. High Flow Acrylics and other acrylic inks are pigment-based, where extremely finely ground pigments are suspended in the binder to make a dispersion. They might need a gentle shake before use to ensure that the pigment particles are evenly distributed throughout the bottle. The advantage of pigment-based inks is that the colour is generally more lightfast; dyes are vulnerable to fading after prolonged exposure to light, whereas pigment-based inks are far more stable, as long as the pigment used is lightfast.

High Flow Acrylics come into their own when used to create watercolour-like effects, staining and highly pigmented gestural washes, on porous substrates, such as paper or raw canvas. Unlike watercolour, the acrylic binder ensures that the paint will be water-resistant and immovable when dry. Golden High Flow Acrylics contain a retarding agent to extend the drying time which gives them excellent spreading capability when painted wet-in-wet. As well as flooding areas with colour, High Flow Acrylics can be used delicately with a small, soft synthetic brush for fine detail. For even finer lines, the paint can be used in refillable markers or with a dip-pen.

While each kind of acrylic paint behaves very differently, all of them dry to form a water-resistant and flexible film. Whether you want to use one type of acrylic paint viscosity, or several in combination, making an informed choice for your work will help you make the most of acrylic paint.