Copal Painting Medium

Frederic Taubes developed and marketed specialized painting media (known as Copal Media) as well as other varnishes and solvents used in oil painting:

Natural Copal Resin and Oil Paint

Tens of thousands of years are then required to turn the mass into a crystal. The resin will be either, “soft,” or, “hard,” depending upon the type of tree. Copal, amber, and Zanzibar, are hard resins. Damar, mastic, and rozin, are soft resins.

Natural resins have been added to oil paint since the sixteenth century. Natural resins add brilliance and durability to the paint body. It is the reason why the paintings of the early Flemish masters look as fresh today as they did when they were painted. In order for a resin to be introduced into paint, it must first be thermally reduced and mixed with a binding agent.

Copal is graded by its color and clarity. The highest quality is a pale golden brown, lighter in color than honey. The poorest quality is dark like molasses and opaque. Only the highest quality copal is suitable for mixture with oil paint.

In 1942, while serving as Carnegie Visiting Professor at the University of Illinois, Frederic Tauibes developed a line of copal painting mediums that closely duplicated the mixtures used by the Flemish masters.

The presence of hard resins in the work of these painters has beenestablished by the Belgian National Laboratories. Taubes Copal Mediums were commercially produced by Permanent Pigments for over 30 years, until artist grade copal became unavailable. In the mid 1970’s industrial grade copal was substituted. This produced an inferior product, and the mediums were eventually discontinued.

The benefits derived from the incorporation of copal resin into oil paint are threefold. Oil paints from the tube do not share a uniform consistency. A medium containing copal will achieve this consistency and facilitate the blending of colors. Second, the gem-like resin enlivens the color and adds brilliancy. Finally, the hard resin invests the paint body with strength and durability.

Permanent Pigments

Copal Medium Magazine Advertisement

COPAL PAINTING MEDIUM (Light, Heavy and Copal Concentrate) formulated by Frederic Taubes, world renowned expert in paint technology, is manufactured by Permanent Pigments lnc. of Cincinnati, Ohio. The media, which to all intents and purposes approximate the ancient formula contained in the Theophilus MS, are, therefore not a new discovery. They have been in use since the Middle Ages and have proven to be the most permanent and versatile of all the paint mediums on the market, whatever their nature.

Proof regarding its behavior, carried out by highly qualified scientific researchers, is contained in the Permanent Pigments publications Painting Media and Varnishes and Enduring Colors for the Artist.

In working qualities the Copal Media offer to the painter the great advantage of working wet-on-wet without unduly disturbing the underlying paint surface. Also blending of colors is immensely enhanced and their depth increased. Moreover, the execution of glazes and scumbles is greatly facilitated, especially when the paint before use has been conditioned by Copal Concentrate. An addition of as much of the Concentrate as the tip of the painting knife holds to about an inch of the paint as it comes from the tube will aid the material in achieving a conformation such as we see it in the paintings of the early Flemish masters.

The paint film produced by Copal Painting Medium is tough and durable. Once the film has aged the copal will not redissolve when the picture is cleaned with solvent as do the soft resins like damar. When damar, a soft resin, is used in a painting medium it remains soluble and makes the painting susceptible to damage by the mildest cleaning agent.

Copal Painting Medium will not darken in time any more than the oil with it normally does. Varying the kind and proportion of the linseed oil in the formula produces different properties for specific uses.

Taubes Copal Painting Medium Light is intended for general painting and alla prima use. With this medium paint can he handled with greater ease without having undue flow or slipperiness. Even greatly thinned paint will not sag or drip down a vertical canvas. Reducing the excess of oil helps prevent yellowing and wrinkling.

Taubes Copal Painting Medium Heavy, made with the heavier stand oils, has greater inherent viscosity.  It is specially suitable for glazing and will level and fuse more effectively.

Taubes Copal Concentrate, composed solely of Copal Resin and Stand Oil, is used by those who wish to paint in a true resin-oil medium and obtain its maximum effect. Copal Concentrate is mixed directly with the tube color and this mixture used [sic] straight or thinned with turpentine.

Taubes Copal Varnish is used both as a special painting medium and as a varnish. As a painting medium it has the ability to stiffen and solidy [sic] Flake White in a few hours and it can also dry rapidly in imprimatura application. This is most useful in priming and under painting.

Since Copal Varnish eventually becomes insoluble in ordinary solvents, it is useful in final varnishing as a thin coat over a well dried painting for permanent protection. After the Copal Varnish is dry, a coat of Taubes Damar Picture Varnish or Damar Matte Varnish is applied in order to have a removable surface varnish for cleaning.

Glazing over LIQUITEX@ Colors — For glazes over underpainting in acrylics use the Copal Painting Medium Heavy with oil colors. Extraordinary coloristic and textural effects can be produced this way.

Mr. Taubes is the author of 28 books on paint techniques and esthetics (ask for them at your public library). He is the American editor of Artist Magazine where he conducts the famous "Taubes Page." He has been professor at seven universities in America and has lectured at Oxford University, the Royal College of Art, London University, etc. His paintings are owned by 27 museums, among them the Metropolitan Museum of Art, the San Francisco Museum, etc.

Superior Varnishes also Formulated by Taubes: Retouching Varnish - Damar Picture Varnish - Matte Picture Varnish - Copal Varnish - Damar Solution Heavy.