MITRA Forum Question Details

​Normally, I put two coats of size onto the working surface of my 140 lb, cotton, wc papers, allowing the coats to dry in between.   Each coat is 25% pH neutral PVA glue and 75% water, per Robert Gamblin.   This makes a perfect surface for me, oil proof, but no more, to allow as much tooth as possible for the paint layer to mechanically bond to.   I know that the oil does not come through because I would see it seep through on the back side, if it did, after I have painted on it.

My interest is in trying some of the commercially made oil papers which, according to the literature, are sized internally.   Each fiber is protected from the ill effects of oil, but the entire paper structure must be otherwise porous to allow oil to enter the paper structure (not touching the individual fibers) and eventually form a strong, mechanical bond when dry.   

My oil sizing was primarily on the surface of the paper, not so with the commercial oil papers.  While they are more "absorbent", I was wondering if they may provide a better mechanical bond with the paint layer than I can currently get by performing my own sizing, or if there was any problem with them that artists or conservators may have noticed or anticipated.     

​Well, I suppose the logical thing to do with a cotton oil paper is to paint on some samples and see if the oil bleeds through.   Don't know how to evaluate the strength of the  mechanical bond of the paint layer to the paper or correctly appraise its strength in comparison to my current method.

I gather that no one yet sees a definitive problem with commercial oil papers, the oil papers being so recent.   Correct?

Oddly enough, I was reading A P Laurie's, The Painter's Methods and Materials, 1926, in which he describes Jan Van Eyke's method of painting in the early to mid 15th C.   It seems that he painted cool colors directly onto the gessoed panel in certain areas, sized it with distemper to make it non-absorbent, and them painted oils over the top.   The coolness of the underlying tempera counteracted the increased warmth and transparency of the oils over time, making the painting appear "fresh" longer.   

The take away here is that the oils bonded to the  non-absorbent distemper for so many years.   An absorbent tempera surface would have soaked up the oil paint, creating a poor effect, according to Laurie.   Painting on a "sized" (distempered) surface was not lost on me and my efforts.

​Returning to the topic of pH neutral PVA glue as a size for cotton paper, on which one wishes to oil paint,  my understanding is that canvas manufacturers have been using it in the production of linen and cotton canvases, a replacement for the more hygroscopic, rabbet skin glue.

If pH neutral PVA size is an inadequate barrier to oil migration over the long term, as suggested earlier, then are modern linen and cotton canvases suspect in their permanence?

I'm using the pH neutral PVA size because it has been the size of choice for the manufacture of linen canvas.   The clarity of it, in relation to arcylic dispersion mediums, (which I use for adhering paper or canvas to panel) would be immaterial as an oil paint layer would be painted on top.

Am I missing something here?

If the permanence of commercially produced oil papers are still an unknown, then I would like to know if what I am doing is particularly inapproriate for the use of studies that may eventually be sold.   

 I use mounted, linen canvas or acrylic primed panel for anything that I intend to sell, but want even my studies to be reasonably permanent as well, in the event that they should be mounted and sold.   Sized paper has come to be my preferred support, even more than linen, but priming it with acryllic primer may really kill the texture and absorbancy of it. 

Thanks for your thoughts.

A question about the recommendation of using solvent-based acrylic as a size for paper for oil painting. Can someone please point me in the direction of a solvent-based acrylic medium, like matte medium? I can only find Golden's MSA colours.​

I have two oil painting paper questions.

I know an artist who uses watercolour paper for oil painting. He says that since it is both internally and externally sized it is a sound practice.

Last year I tested oil painting on 9 oil papers and found that oil painting paper from manufacturers who did not have the equipment for external sizing had seepage of oil through to the back over time. Most of the externally sized papers had some seepage too, though a lot less. 

I emailed all the manufacturers and no one would disclose the sizing material, except the only one that uses gelatine. But they implied that it was different to the material used for sizing watercolour paper. But I got the same amount of seepage or less on my tests with watercolour paper. So I wanted to ask if anyone knows if a different sizing is used for oil paper than for watercolour paper, or if it is a different amount or a different method of application. Or if a hard-sized watercolour paper has a good longevity when used with oil paint.

I also asked the manufacturers about the seeping through of the oil over time and they said it would not affect the longevity of the paper because the internal sizing protects the fibres from the embrittlement of the linseed oil. Does this sound right to you?

​Hello! I have been doing lots of reading/research in this area over the last few months, so thought I might chime in. I have spoken with Tad Spurgeon, author of The Living Craft, about the Arches Oil Paper, and he seems pretty convinced that the sizing they use on that paper is methyl cellulose. 

I have also myself done a series of sizing tests on both Arches and Fabriano watercolour paper using methyl cellulose, and so far, results seem to indicate that two coats of the size on the Arches 300gsm watercolour (HP) paper prevents seepage through to the back. However, bear in mind I use oil stick exclusively, rather than oil paint. Specifically, I've been using the Sennelier oil stick. Still, I have been testing solid blocks of colour on the sized paper and it seems to hold up well.