Sunday, February 12, 2012

Oil Color on Paper

I find that painting on properly prepared quality paper promotes free painting expression. It also allows quick studies and sketches to be casually discarded and start another.

First let us look at paper.  This is sometimes confusing as paper weights are calculated using two basic systems.  The U.S. system which measures the paper weight in pounds. In the U.S. system the same number in pounds can be used for different thicknesses of paper.  The Metric system measures the weight in grams per square meter (gsm). The Metric system is standard across all types of paper because it simply measures one square meter.  For that reason it is a better indicator of the thickness of a paper.  I only use metric for that reason.

The paper should be more than 150 gsm for better performance.  The higher the weight usually means a stiffer and thicker base.  Acid free, all cotton or the equivalent is recommended.  Inferior papers will deteriorate from their own acid content.  Notice how fast a newspaper discolors and becomes brittle.
Some papers that I have tried and like are Lenox 250 gsm and Stonehenge 250 and 320 gsm.  Canson Mi-Teinte 160 gsm is a pastel paper with a smooth and rough side made with 66% rag content.  It is also acid free and has 42 colored pulps to be highly light resistant. I have used Mi-Teinte smooth side in various colors for paintings, using the paper color as the background.

Up date:  90 lbs equals 200 gsm, 140 lbs equals 300 gsm, 300 lbs equals 640 gsm.

For complete information on artist's papers, visit New York Central Art Supply  They have a very detailed paper catalog with papers from around the world divided in various groupings.  They also handle general supplies in another catalog.

Using oils on paper and canvas require sizing.  The sizing seals cotton or linen canvas or in our case, the paper.  The sizing protects the base material from the acid produced by the linseed oil which, over time, will deteriorate the base material.  Canvas usually has a ground over the sizing which is the painting surface.  Paper does not require a ground because the paper is the sealed painting surface.

Since we have paper to use, the acrylic sizing is all that is needed to seal the paper.  I like acrylic matte medium.  It is a clear matte finish when dry and has a very slight tooth which helps the colors cling to the paper.

Apply the acrylic matte medium to the paper with a 2" to 3” foam brush which does not leave bristle marks on the sheet.  Since the acrylic medium is water based, papers on the thin side like Mi-Teinte will expand and buckle.  Use a tackable surface larger than your sheet so you can stretch the sheet flat after wetting. Staple or tack the edges of sheet until it dries.  Overnight drying is a good choice. When the paper is completely dry it is now smooth and ready to paint.

Two quick oil sketches from 2002. The paper is Strathmore 640 gsm, cold pressed, sized, watercolor paper.  The paper has survived well as there are no signs of acid deterioration.

Graphic oil painting on sized, colored Canson Mi-Teinte paper from 2004. Also, there are no signs of oil penetration into the paper.

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