Re: Gum and Photogravure, was: varnishes
16 Kasım 2008, Pazar, 5:21 am tarihinde, Jon Lybrook yazmış:
> If you print using oil *paint* rather than oil-based ink on the plate,
> certain colors do tend to leech through however, bleeding oils, and
> discoloring the paper and print in an undesirable way. This is why
> printmakers, especially those doing monotypes, generally stay away from
> oil paints and stick to oil-based ink only.
But as a matter of fact stiff oil-based ink also/still contains linseed oil?
> Oil paint seeps into and through paper fibers where properly mixed
> etching ink made for intaglio does not.
I think that's a matter of time (a long time maybe - as I mentioned in my
first email). Besides, seeping to the back may not be necessary to affect
the integrity of the paper, since the ink is fully pressed into the paper
and is in direct contact with paper's fibers...
> Wouldn't the information in this thread so far also imply that
> watercolor paintings then last longer than oil paintings because of the
> assertion that gum arabic used in watercolors is less acidic than
> linseed oil?
Not necessarily, because as I said before, the oil doesn't get into paper
fibers due to the usage of a sealant. On the other hand, bad painting and
support preparation techniques may lead to cracking and flaking in the
long run -> as we witness in some old works in the museums / collections.
> This seems contrary to my vague sense about the longevity of watercolors
> vs. oil paintings. I believe I've seen alot more old oil paintings in
> museums than watercolors, for example.
Because there were/are less artists using watercolors as a painting
technique (because it's harder? / looks are different?). That's not caused
by the fact that watercolors are less stable than oil paintings.
On the other hand, watercolor is a much older medium than oil painting; if
I'm not mistaking oil was first used in Renaissance period or just before
it as a paint medium, whereas first watercolors can be dated as old as
Egyptian epoch (not mentioning the cave paintings), or medieval times...