U of S | Mailing List Archive | alt-photo-process-l | Re: Gum and Photogravure, was: varnishes

Re: Gum and Photogravure, was: varnishes

Umm, I'm not sure that's exactly what I said (first line) but I guess the point remains the same: what I meant to say was that only where the pigment has penetrated the paper fibres can a watercolor painting be considered permanent. Any part of the painting where, as you say "watercolor pigments remain suspended in the gum and sit on the surface of the paper" without staining the paper fibres, that part of the painting will remain completely soluble in water. Perhaps we need to check if we're going by the same definition of permanent, but in my definition, an artwork that's water-soluble, in part or whole, doesn't qualify.

I proved this to myself once when I became enamored of painting with watercolor paints with gum added (I'm a painter too); I loved the luscious organic sheen that the added gum imparted to the surface, until one day I recovered my wits and remembered (d'oh) one of the basic principles of gum printing: dried gum arabic is soluble in water. Just to check, I ran a wet brush across one of these paintings that I'd done several months before, and sure enough, the painting dissolved wherever the water touched it. That was the end of my "gum-painting" period. I didn't consider those paintings permanent enough to keep or show, and I washed the paint off the paper.

I said before that I don't have any information to bring to bear on the relative permanence of a gum printing compared to a watercolor painting, meaning a watercolor painting that consists of pigment staining paper. But I think it makes perfect sense to hypothesize that a gum printing, consisting of hardened, insoluble gum, is probably more permanent than a watercolor painting, any part of which consists of pigment suspended in soluble gum arabic.

On Nov 17, 2008, at 6:37 AM, SusanV wrote:

In regard to watercolor paintings... not true that the paint stains the paper and is permanent if the gum is washed out. Many watercolor pigments remain suspended in the gum and sit on the surface of the paper. Only some of the pigments actually stain the paper, and even in those cases if you wash the paint from the surface, the color lightens considerably due to the removal of the top layer of gum/pigment. Having been primarily a watercolor painter for quite a few years, quite a few years ago... I have a lot of experience that includes removal of color from areas both large and small while developing a painting. In fact, terms used by watercolor painters include "staining" and "non-staining" colors.

As to the discussion about the permanence of printmaking ink on paper... that is something I have always wondered about myself. Why is is ok to use oil based ink on paper for an etching, but not when "painting"? Rembrandt's etchings are what... over 300 years old? It must have to do with the smaller percentage of oil in ink when compared to oil "paint".


On Sun, Nov 16, 2008 at 1:50 PM, Katharine Thayer <kthayer@pacifier.com> wrote:

" In the case of watercolor paintings, the image is made of what we in gum printing would call "pigment stain;" it's comprised of pigment which has penetrated the fibers of the paper and colored (stained) them permanently. The gum arabic is only there to serve as a vehicle for the pigment, and its presence in the painting is essentially irrelevant; at any rate after diluting the paint from the tube with water in the typical watercolor painting, there's very little gum arabic in the painting. You could soak most traditional watercolor paintings in water and dissolve the remaining gum arabic without affecting the painting in any material way."

gravure blog at www.susanvossgravures.blogspot.com
website www.dalyvoss.com