Guide to Acrylic Mediums
And Additives
There are so many additives and acrylic mediums available, it can get confusing as to what does what.
And just to further confuse things, remember that in art, there's two meanings of the word 'Medium'.
It can describe the type of paint you're using such as oils or acrylics. But in the context we're looking at here, it means an additive to your acrylic paints.
Here's a resume of the most common acrylic mediums and a brief description of each...
Gel Retarder
Acrylic paint's biggest
asset is its speed of drying. This is also its major drawback
if you're trying to blend colors on the canvas or you're just
not the fastest painter in the world. Retarder slows the
drying speed by up to 50%. Mix it with the color before
applying it. Using more of it with paint increases
transparency. However don't use it to excess in a mix or the
paint won't dry at all! Having said that it's probably going
to be the most used of your acrylic mediums.
Gesso Primer
Used neat to seal
semi-absorbent paint surfaces like unprimed canvas, for both
acrylic and oil painting. Produces matt white surface with a
slight texture or tooth. Can be obtained in black as well.
Flow
Enhancer
Colorless liquid added to colors to
reduce viscocity and enhance flow. Good for large areas of
work where smooth finish is required or straight edges in
conjunction with masking tape. Add bit by bit to the color
until you have the right consistency.
Glaze Medium
Available in gloss or matt
finish. Increases transparency of colors for glazing work.
Glazing is where a translucent color is painted over another
dried color to let that underlying color glow through eg: skin
tones.
Impasto Gel Medium
A heavy gel which,
when added to paint creates a thick, buttery paint which only
loses slight opacity. Bulks out the paint to permit coverage
of large areas of thick (impasto) color. Brush and knife marks
will be retained whilst drying time is slowed slightly.
Available in matt or gloss.
Texture
Paste
A thick, white paste which is used prior
to applying paint. For this reason, one of the most used
acrylic mediums, because it's more economical than using thick
dollops of paint. Depending on thickness used, it may crack.
However, if used in conjunction with Impasto gel, cracks can
be filled in. A combination mix of these two acrylic mediums,
painted over, will work well on flexible surfaces like
stretched canvas.
Pearlescent/Metallic
Tinting Medium
There are a variety of
products available which will add a pearlescent or metallic
shimmer to colors. Used alone, they still provide a
translucent pale colored effect, the actual tint depending
upon manufacturer.
Interference Medium
Similar to
pearlescent medium, these are best used on dark or black
surfaces to get a shimmering metallic effect. When mixed with
another color, the color changes depending which angle it is
viewed from.
Acrylic Matt & Gloss Varnishes
Now
we come on to acrylic mediums which are painted over the top
of your picture as opposed to being mixed with the paint.
These will protect dry acrylic paintings from dust and most
environmental pollution. Can be obtained as a liquid for b ush
application or in a spray format.
However, be careful!
The term 'varnish' tends to be used loosely for any clear, protective coating on a picture. Some acrylic 'varnishes' are spirit-based and can be cleaned off at any time in years to come with low odor thinners or turpentine. The picture can then be re-coated with clean varnish.
Many acrylic 'varnishes' however are water-based and made from an acrylic polymer, similar to acrylic paints. Once dry, they cannot be removed. Like their spirit-based counterparts they resist blooming, cracking and yellowing if used correctly.
However, if circumstances arose in the future where you wanted
to replace this type of coating, you've got a problem. So when
using a varnish, always check out beforehand
whether it can be removed and whether this is likely to be an
issue for you.
Related Aricles
Getting started with acrylic paints
The
acrylic paint technique offers both the new and experienced
artist a very versatile method of painting...
Which
are the best acrylic paint brushes?
Painting
with acrylics can be great fun. However, the acrylic paint
brushes you use are essential to the quality of your finished
painting.
Using
oil and acrylic paper for your paintings
Don't
dismiss the various types of oil and acrylic paper available
to the artist as being just for practice work...
Return
from this acrylic mediums page
to the main acrylic
painting section
